Neuraxial blocks

Neuraxial blocks DEFAULT

Major complications of central neuraxial block: report on the Third National Audit Project of the Royal College of Anaesthetists

Abstract

Background

Serious complications of central neuraxial block (CNB) are rare. Limited information on their incidence and impact impedes clinical decision-making and patient consent. The Royal College of Anaesthetists Third National Audit Project was designed to inform this situation.

Methods

A 2 week national census estimated the number of CNB procedures performed annually in the UK National Health Service. All major complications of CNBs performed over 1 yr (vertebral canal abscess or haematoma, meningitis, nerve injury, spinal cord ischaemia, fatal cardiovascular collapse, and wrong route errors) were reported. Each case was reviewed by an expert panel to assess causation, severity, and outcome. ‘Permanent’ injury was defined as symptoms persisting for more than 6 months. Efforts were made to validate denominator (procedures performed) and numerator (complications) data through national databases.

Results

The census phase produced a denominator of 707 455 CNB. Eighty-four major complications were reported, of which 52 met the inclusion criteria at the time they were reported. Data were interpreted ‘pessimistically’ and ‘optimistically’. ‘Pessimistically’ there were 30 permanent injuries and ‘optimistically’ 14. The incidence of permanent injury due to CNB (expressed per 100 000 cases) was ‘pessimistically’ 4.2 (95% confidence interval 2.9–6.1) and ‘optimistically’ 2.0 (1.1–3.3). ‘Pessimistically’ there were 13 deaths or paraplegias, ‘optimistically’ five. The incidence of paraplegia or death was ‘pessimistically’ 1.8 per 100 000 (1.0–3.1) and ‘optimistically’ 0.7 (0–1.6). Two-thirds of initially disabling injuries resolved fully.

Conclusions

The data are reassuring and suggest that CNB has a low incidence of major complications, many of which resolve within 6 months.

Central neuraxial block (CNB) techniques can produce highly effective pain relief for a wide variety of indications and may decrease patient morbidity after major surgery, although the extent of the latter benefit is not agreed universally.1,2 In recent years, both large randomized controlled trials (RCTs)3 and meta-analysis2 have led to conflicting conclusions and interpretations regarding the outcome benefit of CNB techniques. However, the risk–benefit analysis must also take into account both the rate of failure of the techniques, which may be higher than some accept,4 and the incidence of complications.5–7 In the past, these complications have been serious enough to turn the speciality away from the techniques almost entirely, particularly when reports of paraplegia after spinal anaesthesia in both the USA8 and the UK9 led to the near abandonment of CNB in the UK for more than two decades after the Second World War. With the techniques now used widely again, there are reports of, and commentaries on, major complications from both the UK and elsewhere.10–17 Most recently, Christie and McCabe18 reported a series from one hospital that, with a very high incidence of major sequelae, achieved some prominence.

Knowledge of the incidence of such complications should be an essential component of the clinical decision-making and consent processes, but there are few good data which can be quoted to support such discussions, leaving both patient and clinician in a quandary. Figures (ranging from 1:1000 to 1:100 000) are quoted, but their doubtful validity questions the ability to obtain genuinely informed consent from patients offered these procedures. Recognizing this, and that neither RCT nor meta-analysis is an appropriate method for identifying rare events, the Council of the Royal College of Anaesthetists devoted its third National Audit Project to this topic. The aim was a prospective attempt to identify both numerator (number of major complications) and denominator (number of CNB) information for a 12 month period by a review across the breadth of anaesthetic and pain management practice in the UK National Health Service (NHS). Follow-up (as far as an anonymous reporting system would allow) would extend to 6 months so that final outcome, and incidence, could be assessed and give some indication of the prognosis of such events.

Methods

A two-part project was devised: first, an assessment of the number of CNBs performed annually in the UK NHS (for denominator information); and second, an audit of the major complications of these procedures performed during a 12 month period (for numerator information). Discussions with the Centre of Research Ethics Committees (now National Research Ethics Service) indicated that ethical approval was not required, and the processes involved were agreed with the Patient Information Advisory Group of the Department of Health. The project was advertised widely throughout 2006 and 2007 through direct contact with the relevant organizations in anaesthesia, pain management, neurology, spinal surgery, radiology, and neuroradiology (Appendix 1). The aims and processes of the project were explained and the information was cascaded down to the members of those organizations at regular intervals.

Denominator data

A detailed description of the first part, the ‘snapshot’ survey (census) to determine denominator information, has been published already,19 but a brief summary is appropriate here. Between March and September 2006, the anaesthetic department of each NHS hospital believed to be performing surgery was contacted, asked to participate, and to nominate a ‘local reporter’ (LR) to co-ordinate the project locally. Each LR was asked to collect information on the number of CNBs performed over a 2 week period at the end of September 2006 or an equivalent period at about that time. The blocks were classified as epidurals, spinals, combined spinal–epidurals (CSEs), and caudals for each of the five indications: adult perioperative, obstetric (both labour analgesia and operative delivery), chronic pain, paediatric perioperative, and administered by a non-anaesthetist. We did not request data on CNB that were attempted and failed as we considered it unlikely that all cases would be recorded reliably. For each category, the reporters indicated whether their data were ‘accurate’, a ‘close estimate’, or an ‘approximate estimate’. The mechanism of data collection was not specified and reminders to return information were sent at regular intervals by post, e-mail, and telephone as necessary. Data were summed to give cumulative totals for a nominal 2 week period and, based on the annual results of one large district general hospital (Royal United Hospital, Bath), these figures were then multiplied by 25 to give an approximation of annual activity.

Event reporting (numerator data)

The same LR system was used to identify complications of CNB, but direct reports from any clinician in all relevant specialities were promoted with the aim of ensuring complete capture of all possible cases. We accepted reports even if the attempted CNB was abandoned: as such, there is a potential to slightly overestimate the incidence of complications because we did not include these attempts in the denominator. The formal audit period was September 1, 2006, to August 31, 2007, inclusive, but reporting was actively encouraged until March 31, 2008, for the same reason. Information was sought on all major complications of CNB with the potential for serious patient harm, including infection, haematoma, nerve damage, and cardiovascular collapse (detailed in Table 1). In addition, because of current concern about wrong route errors (i.e. a drug intended for the epidural or subarachnoid space inadvertently administered i.v., or vice versa),20 reports on these events were encouraged even when no injury occurred.

Table 1

Complications sought in the audit process

Complication . Example . 
Spinal infections Epidural abscess, meningitis 
Spinal bleeding Vertebral canal haematoma 
Major nerve damage Spinal cord damage, spinal cord infarction, paraplegia, major neuropathy 
Wrong route injection errors Epidural/intrathecal drugs given i.v. or vice versa
Death where the anaesthetic/analgesic procedure is implicated as causal Cardiovascular collapse, other 
Complication . Example . 
Spinal infections Epidural abscess, meningitis 
Spinal bleeding Vertebral canal haematoma 
Major nerve damage Spinal cord damage, spinal cord infarction, paraplegia, major neuropathy 
Wrong route injection errors Epidural/intrathecal drugs given i.v. or vice versa
Death where the anaesthetic/analgesic procedure is implicated as causal Cardiovascular collapse, other 

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Table 1

Complications sought in the audit process

Complication . Example . 
Spinal infections Epidural abscess, meningitis 
Spinal bleeding Vertebral canal haematoma 
Major nerve damage Spinal cord damage, spinal cord infarction, paraplegia, major neuropathy 
Wrong route injection errors Epidural/intrathecal drugs given i.v. or vice versa
Death where the anaesthetic/analgesic procedure is implicated as causal Cardiovascular collapse, other 
Complication . Example . 
Spinal infections Epidural abscess, meningitis 
Spinal bleeding Vertebral canal haematoma 
Major nerve damage Spinal cord damage, spinal cord infarction, paraplegia, major neuropathy 
Wrong route injection errors Epidural/intrathecal drugs given i.v. or vice versa
Death where the anaesthetic/analgesic procedure is implicated as causal Cardiovascular collapse, other 

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Primary notification of an event was by e-mail, with reports accepted from any source. The project team was able to exclude obviously irrelevant cases at this stage, but otherwise the LR for the relevant hospital was asked to obtain the details and upload them to a secure, password-protected website (the National Confidential Acute Pain Critical Incident Audit, NCAPCIA, www.ncapcia.org.uk). The information requested depended on the type of incident, but the questions were designed to gain a full picture of the procedure and the presentation, severity, and consequences of the complication. The NCAPCIA administrator (D.C.) was able to access these reports and request updates as required, being the only person who knew their source: this was essential to allow requests for clarification and updates of information while maintaining confidentiality. Each case was reviewed in detail by a panel representing all the specialities involved in the project (Appendix 2), and the following details were confirmed:

  • type of block and indication for its performance (as described above). Procedures performed for the control of non-operative acute pain (e.g. fractured ribs and pancreatitis) were included in the perioperative group;

  • category of complication (Table 1);

  • correctness of diagnosis;

  • date of CNB within the audit period;

  • CNB was performed in an NHS hospital;

  • severity of patient outcome (see below), initially and at 6 months (or later where such information was available);

  • causation: whether the CNB was the cause of the patient injury: certain, likely, possible, unlikely, and no link.

Severity of complications

Severity of initial and final harm was recorded in a variety of ways. First, it was categorized according to the National Patient Safety Agency (NPSA) severity of outcome scale for patient safety incidents (Table 2).21 Patient harm was graded as ‘temporary’ if the incident met the NPSA criteria for moderate injury, and ‘permanent’ if the outcome was worse than this (severe injury or death). Secondly, where injury was permanent, or assumed to be so, the features were classified as follows:

  • sensory only;

  • motor: motor weakness of whatever severity, with or without sensory symptoms;

  • paraplegia: paraplegia or tetraplegia with or without additional motor or sensory symptoms;

  • death: this was classified as ‘direct’ (e.g. a cervical abscess leading to tetraplegia, respiratory failure, and death) or ‘indirect’ when the CNB was followed by a series of other events leading to death (e.g. an abscess requiring decompression with good neurological recovery, but complicated by a fatal pulmonary embolism).

Table 2

National Patient Safety Agency severity of outcome scale for patient safety incidents. *First aid, additional therapy, or additional medication. Excludes extra stay in hospital, return to surgery, or readmission. Return to surgery, unplanned re-admission, prolonged episode of care as in or out patient or transfer to another area such as ICU. Permanent lessening of bodily functions, sensory, motor, physiologic, or intellectual

Grade of severity . Description . 
None No harm (whether lack of harm was due to prevention or not) 
Low Minimal harm but necessitating extra observation or minor treatment* 
Moderate Significant, but not permanent harm, or moderate increase in treatment
Severe Permanent harm due to the incident
Death Death due to the incident 
Grade of severity . Description . 
None No harm (whether lack of harm was due to prevention or not) 
Low Minimal harm but necessitating extra observation or minor treatment* 
Moderate Significant, but not permanent harm, or moderate increase in treatment
Severe Permanent harm due to the incident
Death Death due to the incident 

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Table 2

National Patient Safety Agency severity of outcome scale for patient safety incidents. *First aid, additional therapy, or additional medication. Excludes extra stay in hospital, return to surgery, or readmission. Return to surgery, unplanned re-admission, prolonged episode of care as in or out patient or transfer to another area such as ICU. Permanent lessening of bodily functions, sensory, motor, physiologic, or intellectual

Grade of severity . Description . 
None No harm (whether lack of harm was due to prevention or not) 
Low Minimal harm but necessitating extra observation or minor treatment* 
Moderate Significant, but not permanent harm, or moderate increase in treatment
Severe Permanent harm due to the incident
Death Death due to the incident 
Grade of severity . Description . 
None No harm (whether lack of harm was due to prevention or not) 
Low Minimal harm but necessitating extra observation or minor treatment* 
Moderate Significant, but not permanent harm, or moderate increase in treatment
Severe Permanent harm due to the incident
Death Death due to the incident 

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Interpretation of reports

In a proportion of cases, LRs were not able to provide full details of cases and patient progress, and some information was incomplete in spite of follow-up requests. Therefore, the reports required some ‘interpretation’ by the review panel, which assumed the worst, unless there was evidence to refute it:

  • Diagnosis: where this was uncertain, cases were included: only those with clear evidence of incorrect diagnosis were excluded.

  • Causation and outcome: these were particularly difficult to judge in a number of cases, and this led to a decision to quote rates of complications in two ways, that is, in terms of both ‘worst’ and ‘best’ case scenarios, defined in the results as ‘pessimistic’ and ‘optimistic’ incidences. When causation was judged certain, likely, possible, or unlikely, cases were included in the ‘pessimistic’ analysis, but those judged as unlikely were excluded from the ‘optimistic’ analysis. Similarly, efforts were made to determine the patient outcome at 6 months after the CNB. Where outcome at 6 months (or later) was available, this was used in the final judgement, but if such outcome information was only available from an earlier date, that outcome was assumed to have persisted—the ‘pessimistic’ outcome.

  • Thus, the results are presented both cautiously (the ‘pessimistic’ figures) and pragmatically (the ‘optimistic’ figures).

Validation of data

Requests were made to several organizations for information which might validate (i.e. confirm the completeness of) both denominator and numerator data. For the denominator, this included the National Joint Registry, the National Obstetric Anaesthesia Database, and the Department of Health Hospital Episodes Statistics. For the numerator, we sought evidence of relevant cases from the NHS Litigation Authority (NHSLA) and National Reporting and Learning Service (NRLS) of the NPSA, the Medical Protection Society, and the Medical Defence Union. Medical journals were checked for reports of relevant cases and authors contacted as necessary. The internet search engine ‘Google’ was used to search for news items published on the internet with the words (epidural, spinal, death, abscess, haematoma, and infection).

Incidence calculations

Cases were included in the numerator where a complication of CNB led to permanent patient harm and the CNB had been performed within the audit period and in an NHS hospital.

The data were entered into a Microsoft Excel 2007 spreadsheet (Microsoft Corporation, USA) and incidences were calculated (by dividing the numerator for a given group by the relevant denominator). Confidence intervals (CIs) were derived using binomial probability tests with the stat-conf programme (Handbook of Biological Statistics 2008, http://udel.edu/~mcdonald/statconf.html). The primary end-points of the study were the incidences (both ‘pessimistic’ and ‘optimistic’) of permanent harm due to complications of the various types of CNB performed within the 1 yr audit period in an NHS hospital. The incidence of decompressive laminectomy in adult patients undergoing a perioperative epidural block was also calculated.

Results

This report focuses primarily on the quantitative aspects of the project. A full report, with expanded clinical details and analysis to identify clinical learning points will be published simultaneously by the Royal College of Anaesthetists (www.rcoa.ac.uk).

By September 2006, all 309 hospitals which had been contacted had agreed to participate and had appointed an LR.

Denominator data (snapshot returns)

The original publication of ‘snapshot’ data was based on reports from 97% of hospitals,19 but since then returns have been received from the final 3%. Thus, the denominator data (Table 3) used in the calculation of incidences of complications are based on returns from all the hospitals surveyed, 92% of them grading their figures as ‘accurate’. Extrapolating to annual activity by using a multiplier of 25 (see comment above) suggests that a total of just more than 700 000 CNB procedures [∼325 000 (46% of total) subarachnoid blocks, 293 000 (41%) epidurals, 42 000 (6%) CSEs, and 47 000 (7%) caudals] are performed annually in the UK. The majority of CNBs were performed for obstetric (45%) or perioperative care (44%) indications.

Table 3

Census phase: estimate of the number of CNB procedures performed annually in 309 UK NHS hospitals (100% return). Figures in parentheses are percentages: in the right column, the percentage of all CNB that were of the type of block of the relevant row, and in the penultimate row, the percentage of all CNB that were performed for the clinical indication of the relevant column. ‘Non-anaesthetists’ include neurosurgeons, spinal surgeons, orthopaedic surgeons, rheumatologists, ‘physicians’, and general practitioners. The bottom row indicates the percentage of returns recorded as ‘accurate’: others were close estimates, or estimates

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Totals: block types . 
Epidural 97 925 161 550 27 975 3125 2475 293 050 (41.4) 
Spinal 189 000 133 525 1325 325 775 324 950 (46) 
CSE 16 525 25 350 41 875 (5.9) 
Caudal 9000 11 375 18 050 9125 47 550 (6.7) 
Totals: indications 312 450 (44.2) 320 425 (45.3) 40 675 (5.7) 21 500 (3.0) 12 375 (1.7) 707 425 (100) 
% Accurate replies 83% 95% 94% 91% 91% 92% 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Totals: block types . 
Epidural 97 925 161 550 27 975 3125 2475 293 050 (41.4) 
Spinal 189 000 133 525 1325 325 775 324 950 (46) 
CSE 16 525 25 350 41 875 (5.9) 
Caudal 9000 11 375 18 050 9125 47 550 (6.7) 
Totals: indications 312 450 (44.2) 320 425 (45.3) 40 675 (5.7) 21 500 (3.0) 12 375 (1.7) 707 425 (100) 
% Accurate replies 83% 95% 94% 91% 91% 92% 

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Table 3

Census phase: estimate of the number of CNB procedures performed annually in 309 UK NHS hospitals (100% return). Figures in parentheses are percentages: in the right column, the percentage of all CNB that were of the type of block of the relevant row, and in the penultimate row, the percentage of all CNB that were performed for the clinical indication of the relevant column. ‘Non-anaesthetists’ include neurosurgeons, spinal surgeons, orthopaedic surgeons, rheumatologists, ‘physicians’, and general practitioners. The bottom row indicates the percentage of returns recorded as ‘accurate’: others were close estimates, or estimates

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Totals: block types . 
Epidural 97 925 161 550 27 975 3125 2475 293 050 (41.4) 
Spinal 189 000 133 525 1325 325 775 324 950 (46) 
CSE 16 525 25 350 41 875 (5.9) 
Caudal 9000 11 375 18 050 9125 47 550 (6.7) 
Totals: indications 312 450 (44.2) 320 425 (45.3) 40 675 (5.7) 21 500 (3.0) 12 375 (1.7) 707 425 (100) 
% Accurate replies 83% 95% 94% 91% 91% 92% 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Totals: block types . 
Epidural 97 925 161 550 27 975 3125 2475 293 050 (41.4) 
Spinal 189 000 133 525 1325 325 775 324 950 (46) 
CSE 16 525 25 350 41 875 (5.9) 
Caudal 9000 11 375 18 050 9125 47 550 (6.7) 
Totals: indications 312 450 (44.2) 320 425 (45.3) 40 675 (5.7) 21 500 (3.0) 12 375 (1.7) 707 425 (100) 
% Accurate replies 83% 95% 94% 91% 91% 92% 

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None of the databases consulted in an attempt to validate these data provided information that could be used for that purpose.

Numerator data (complications reported)

Event returns and validation of completeness

In total, 108 cases were reported directly to the project team or through NCAPCIA, with 84 of these being considered appropriate for panel review. The 24 cases eliminated by the project team before panel review were all minor complications of no relevance to the problems under consideration: when there was the slightest doubt, the cases were included for review.

The NHSLA and NRLS databases were screened by the NPSA for all reports relating to CNB performed in the audit period. This identified ∼1700 cases reported to the NRLS (of which 13 were reported to have a serious or fatal outcome) and five cases notified to the NHSLA. The audit lead (T.M.C.) reviewed an unselected subset of 200 of the NRLS cases, all NRLS cases with a serious or fatal outcome, and all NHSLA cases. The NRLS review identified only one case meeting the criteria of the current project (in the 13 serious cases): this had already been reported. Two NHSLA cases were potentially relevant. One (a wrong route injection error) clearly met NAP3's inclusion criteria, but did not match the details of any cases reported at that time. A second case (of nerve injury) possibly met the inclusion criteria, but it was not clear whether it had been reported or not. Both hospitals were contacted by the NPSA and asked to report the case if it met inclusion criteria and had not been reported already. The wrong route injection case was subsequently reported to NCAPCIA and is included with those reviewed in detail.

Review of the literature identified three potential cases for inclusion, but discussion with the authors of the papers indicated that they did not meet the criteria. Internet-based news ‘alerts’ identified the wrong route injection case also identified by NHSLA screening. Other sources of validation did not identify any further cases.

Sources and timing of reports

Although the methodology of the system meant that anonymous reporting was possible, the majority (67) of cases were from identified individuals: 56 anaesthetists, nine neurologists, and two acute pain nurses. Similarly, other details cannot be described in full, but reports were received from all areas of the UK. Four hospitals reported more than one event, but two of these had neurosurgical units and were reporting complications of CNBs which had been performed elsewhere. It was not possible to obtain detailed information about the dual reports from the other two hospitals.

Events were notified throughout the audit period, but only one was reported after December 2007 and that was in August 2008, 5 months after the formal closure date. However, review indicated that it should be included in the analysis, even at a late stage.

Review panel assessments

Eighty-four cases were reviewed. Thirty-two cases were either performed outside the period of the audit, not performed in the NHS, or the complication did not meet the diagnostic criteria of the audit (wrong diagnosis, no link between CNB and notified complication, or full recovery of the complication at the time it was notified). Fifty-two cases therefore met all of the audit's inclusion criteria and efforts were made to follow-up these cases for a minimum of 6 months (Table 4). All 84 were reviewed for learning points for the clinical report to be published elsewhere (www.rcoa.ac.uk), but the remaining 52 are the focus of this analysis of the determination of permanent injury after CNB. Of these 52 patients, 22 made a fully documented complete recovery from their serious complication (NPSA classification ‘moderate’, Table 2): seven epidural abscesses, seven nerve or spinal cord injuries, three cardiovascular collapses [requiring cardiopulmonary resuscitation or admission to intensive care (ICU)], three cases of meningitis, one vertebral canal haematoma, and one other (intrathecal opioid overdose leading to respiratory arrest). These cases are not considered further. The remaining 30 events were used in the calculation of the ‘pessimistic’ incidences of permanent harm after CNB techniques. Detailed review indicated that in 16 cases, the patients were either likely to make a good recovery or the attribution of the permanent harm to the block was tenuous. This left 14 events for the calculation of the ‘optimistic’ incidences.

Table 4

Summary of cases reviewed and their classification by review panel. Exclusion from review was due to wrong diagnosis, minor injury, full recovery before notification, and procedure performed outside the dates of the audit or in a non-NHS hospital. See text for definitions of ‘pessimistic’ and ‘optimistic’ categories

Category . Total . Excluded from review . Excluded from incidence calculation: full recovery during follow-up . Included: pessimistic incidence calculation . Included: optimistic incidence calculations . 
Epidural abscess 20 
Meningitis 
Vertebral canal haematoma 
Nerve injury 18 
Spinal cord ischaemia 
Wrong route error 11 10 
Cardiovascular collapse 
Miscellaneous 
Total 84 32 22 30 14 
Category . Total . Excluded from review . Excluded from incidence calculation: full recovery during follow-up . Included: pessimistic incidence calculation . Included: optimistic incidence calculations . 
Epidural abscess 20 
Meningitis 
Vertebral canal haematoma 
Nerve injury 18 
Spinal cord ischaemia 
Wrong route error 11 10 
Cardiovascular collapse 
Miscellaneous 
Total 84 32 22 30 14 

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Table 4

Summary of cases reviewed and their classification by review panel. Exclusion from review was due to wrong diagnosis, minor injury, full recovery before notification, and procedure performed outside the dates of the audit or in a non-NHS hospital. See text for definitions of ‘pessimistic’ and ‘optimistic’ categories

Category . Total . Excluded from review . Excluded from incidence calculation: full recovery during follow-up . Included: pessimistic incidence calculation . Included: optimistic incidence calculations . 
Epidural abscess 20 
Meningitis 
Vertebral canal haematoma 
Nerve injury 18 
Spinal cord ischaemia 
Wrong route error 11 10 
Cardiovascular collapse 
Miscellaneous 
Total 84 32 22 30 14 
Category . Total . Excluded from review . Excluded from incidence calculation: full recovery during follow-up . Included: pessimistic incidence calculation . Included: optimistic incidence calculations . 
Epidural abscess 20 
Meningitis 
Vertebral canal haematoma 
Nerve injury 18 
Spinal cord ischaemia 
Wrong route error 11 10 
Cardiovascular collapse 
Miscellaneous 
Total 84 32 22 30 14 

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Patient characteristics

Events were distributed across both genders and the range of ASA status, with the majority of events occurring after elective surgical procedures and about half the CNBs having been performed by consultants and half by other grades (Table 5). There were no children in the 52 patients in the audit, and the majority of cases occurred in patients aged more than 50 yr. In the 30 patients with permanent harm (judged ‘pessimistically’), the complications were spread across all types of CNB: 18 (60%) followed epidural block and seven (23%) spinal anaesthesia. As far as clinical indication was concerned, 25 (83%) were in the perioperative group (Table 6).

Table 5

Patient characteristics data of cases reviewed by panel. See text for definitions of ‘pessimistic’ and ‘optimistic’ categories. *Based on reporter's data with some interpretation. Not all data were requested for groups of complications (e.g. operator details were not requested for cardiovascular collapse, wrong route errors, or miscellany)

Cases included (n=52) . Cases with permanent injury (pessimistic interpretation) (n=30) . Cases with permanent injury (optimistic interpretation) (n=14) . 
Gender 
 Female:male 33:19 17:13 7:7 
Age (yr) 
 <16 
 16–50 16 
 51–70 17 
 >70 19 13 
ASA grade* 
 I–II 33 16 
 III–IV 17 13 
 Not assessed 
Surgery 
 Major:not major:none 33:11:8 21:5:4 10:2:2 
 Elective:emergency (total operations) 33:11 (44) 21:5 (26) 11:1 (12) 
Site of nursing 
 Ward:ICU:died in theatre 11:34:2 16:10:2 10:2:1 
 Not recorded 
Operator for procedure
 Consultant 27 15 
 Non-consultant-career grade 
 Specialist registrar 
 Senior house officer 
 Not recorded 10 
Cases included (n=52) . Cases with permanent injury (pessimistic interpretation) (n=30) . Cases with permanent injury (optimistic interpretation) (n=14) . 
Gender 
 Female:male 33:19 17:13 7:7 
Age (yr) 
 <16 
 16–50 16 
 51–70 17 
 >70 19 13 
ASA grade* 
 I–II 33 16 
 III–IV 17 13 
 Not assessed 
Surgery 
 Major:not major:none 33:11:8 21:5:4 10:2:2 
 Elective:emergency (total operations) 33:11 (44) 21:5 (26) 11:1 (12) 
Site of nursing 
 Ward:ICU:died in theatre 11:34:2 16:10:2 10:2:1 
 Not recorded 
Operator for procedure
 Consultant 27 15 
 Non-consultant-career grade 
 Specialist registrar 
 Senior house officer 
 Not recorded 10 

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Table 5

Patient characteristics data of cases reviewed by panel. See text for definitions of ‘pessimistic’ and ‘optimistic’ categories. *Based on reporter's data with some interpretation. Not all data were requested for groups of complications (e.g. operator details were not requested for cardiovascular collapse, wrong route errors, or miscellany)

Cases included (n=52) . Cases with permanent injury (pessimistic interpretation) (n=30) . Cases with permanent injury (optimistic interpretation) (n=14) . 
Gender 
 Female:male 33:19 17:13 7:7 
Age (yr) 
 <16 
 16–50 16 
 51–70 17 
 >70 19 13 
ASA grade* 
 I–II 33 16 
 III–IV 17 13 
 Not assessed 
Surgery 
 Major:not major:none 33:11:8 21:5:4 10:2:2 
 Elective:emergency (total operations) 33:11 (44) 21:5 (26) 11:1 (12) 
Site of nursing 
 Ward:ICU:died in theatre 11:34:2 16:10:2 10:2:1 
 Not recorded 
Operator for procedure
 Consultant 27 15 
 Non-consultant-career grade 
 Specialist registrar 
 Senior house officer 
 Not recorded 10 
Cases included (n=52) . Cases with permanent injury (pessimistic interpretation) (n=30) . Cases with permanent injury (optimistic interpretation) (n=14) . 
Gender 
 Female:male 33:19 17:13 7:7 
Age (yr) 
 <16 
 16–50 16 
 51–70 17 
 >70 19 13 
ASA grade* 
 I–II 33 16 
 III–IV 17 13 
 Not assessed 
Surgery 
 Major:not major:none 33:11:8 21:5:4 10:2:2 
 Elective:emergency (total operations) 33:11 (44) 21:5 (26) 11:1 (12) 
Site of nursing 
 Ward:ICU:died in theatre 11:34:2 16:10:2 10:2:1 
 Not recorded 
Operator for procedure
 Consultant 27 15 
 Non-consultant-career grade 
 Specialist registrar 
 Senior house officer 
 Not recorded 10 

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Table 6

Complications used in calculation of ‘pessimistic’ (see text for explanation) incidences related to type of block and clinical indication

Cases . Epidural/spinal/CSE/caudal . Perioperative/obstetric/chronic pain/paediatrics/non-anaesthetist . 
Epidural abscess 5/2/0/1 6/1/1/0/0 
Meningitis 0/0/0/0 0/0/0/0/0 
Vertebral canal haematoma 5/0/0/0 5/0/0/0/0 
Nerve injury 3/3/1/0 5/2/0/0/0 
Spinal cord infarction 4/0/0/0 4/0/0/0/0 
Wrong route 0/0/1/0 1/0/0/0/0 
Cardiovascular collapse 0/2/1/0 3/0/0/0/0 
Miscellaneous 1/0/1/0 1/1/0/0/0 
Total 30 18/7/4/1 25/4/1/0/0 
Cases . Epidural/spinal/CSE/caudal . Perioperative/obstetric/chronic pain/paediatrics/non-anaesthetist . 
Epidural abscess 5/2/0/1 6/1/1/0/0 
Meningitis 0/0/0/0 0/0/0/0/0 
Vertebral canal haematoma 5/0/0/0 5/0/0/0/0 
Nerve injury 3/3/1/0 5/2/0/0/0 
Spinal cord infarction 4/0/0/0 4/0/0/0/0 
Wrong route 0/0/1/0 1/0/0/0/0 
Cardiovascular collapse 0/2/1/0 3/0/0/0/0 
Miscellaneous 1/0/1/0 1/1/0/0/0 
Total 30 18/7/4/1 25/4/1/0/0 

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Table 6

Complications used in calculation of ‘pessimistic’ (see text for explanation) incidences related to type of block and clinical indication

Cases . Epidural/spinal/CSE/caudal . Perioperative/obstetric/chronic pain/paediatrics/non-anaesthetist . 
Epidural abscess 5/2/0/1 6/1/1/0/0 
Meningitis 0/0/0/0 0/0/0/0/0 
Vertebral canal haematoma 5/0/0/0 5/0/0/0/0 
Nerve injury 3/3/1/0 5/2/0/0/0 
Spinal cord infarction 4/0/0/0 4/0/0/0/0 
Wrong route 0/0/1/0 1/0/0/0/0 
Cardiovascular collapse 0/2/1/0 3/0/0/0/0 
Miscellaneous 1/0/1/0 1/1/0/0/0 
Total 30 18/7/4/1 25/4/1/0/0 
Cases . Epidural/spinal/CSE/caudal . Perioperative/obstetric/chronic pain/paediatrics/non-anaesthetist . 
Epidural abscess 5/2/0/1 6/1/1/0/0 
Meningitis 0/0/0/0 0/0/0/0/0 
Vertebral canal haematoma 5/0/0/0 5/0/0/0/0 
Nerve injury 3/3/1/0 5/2/0/0/0 
Spinal cord infarction 4/0/0/0 4/0/0/0/0 
Wrong route 0/0/1/0 1/0/0/0/0 
Cardiovascular collapse 0/2/1/0 3/0/0/0/0 
Miscellaneous 1/0/1/0 1/1/0/0/0 
Total 30 18/7/4/1 25/4/1/0/0 

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Incidence of permanent harm

Considering the overall totals first, the incidence of any permanent injury (NPSA classifications serious and fatal, Table 2) after all CNBs in this survey is 4.2 per 100 000 (95% CI 2.9–6.1; equivalent to 1 in 23 500) using the ‘pessimistic’ assessment of outcome, and 2.0 per 100 000 (95% CI 1.1–3.3; 1 in 50 500) with the ‘optimistic’ assessment. However, there was a considerable variation between the incidences after different types of block. In both ‘pessimistic’ and ‘optimistic’ assessments, epidural and CSE were associated with higher incidences than both spinal and caudal blocks. Looking at clinical indication also revealed similar variation.

By using the subgroups we used in the census phase (Table 3), it is possible to calculate incidences for each of the subgroups. We report these for completeness (Tables 7–10), but as discussed below caution against their over-interpretation. The incidence of complications was highest after perioperative use and considerably lower in other groups (Tables 7 and 8). The incidence of permanent injury after adult perioperative epidural anaesthesia or analgesia was ‘pessimistically’ 17.4 per 100 000 (95% CI 7.2–27.8; 1 in 5800) and ‘optimistically’ 8.2 per 100 000 (95% CI 3.5–16.1; 1 in 12 200). Twelve patients in this category underwent decompressive laminectomy (seven for abscess, four for vertebral canal haematoma, and one as a result of nerve injury in association with spinal stenosis), an incidence of 12.3 per 100 000 cases (95% CI 6.3–21.4, 1 in 8100). One patient declined laminectomy.

Table 7

Incidence of permanent harm (including death) after CNB with ‘pessimistic’ (see text for explanation) interpretation of data: events per 100 000 cases (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot’ phase of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 17.4 (7.2–27.8) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 6.1 (3.6–9.7) 
Spinal 2.6 (1.0–6.2) 1.5 (1.0–5.4) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 2.2 (1.0–4.4) 
CSE 18.2 (3.7–53.0) 3.9 (1.0–22.0) N/A N/A N/A 9.6 (2.6–24.5) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 8.0 (5.2–11.8) 1.2 (1.0–3.2) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 4.2 (2.9–6.1) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 17.4 (7.2–27.8) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 6.1 (3.6–9.7) 
Spinal 2.6 (1.0–6.2) 1.5 (1.0–5.4) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 2.2 (1.0–4.4) 
CSE 18.2 (3.7–53.0) 3.9 (1.0–22.0) N/A N/A N/A 9.6 (2.6–24.5) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 8.0 (5.2–11.8) 1.2 (1.0–3.2) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 4.2 (2.9–6.1) 

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Table 7

Incidence of permanent harm (including death) after CNB with ‘pessimistic’ (see text for explanation) interpretation of data: events per 100 000 cases (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot’ phase of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 17.4 (7.2–27.8) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 6.1 (3.6–9.7) 
Spinal 2.6 (1.0–6.2) 1.5 (1.0–5.4) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 2.2 (1.0–4.4) 
CSE 18.2 (3.7–53.0) 3.9 (1.0–22.0) N/A N/A N/A 9.6 (2.6–24.5) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 8.0 (5.2–11.8) 1.2 (1.0–3.2) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 4.2 (2.9–6.1) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 17.4 (7.2–27.8) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 6.1 (3.6–9.7) 
Spinal 2.6 (1.0–6.2) 1.5 (1.0–5.4) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 2.2 (1.0–4.4) 
CSE 18.2 (3.7–53.0) 3.9 (1.0–22.0) N/A N/A N/A 9.6 (2.6–24.5) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 8.0 (5.2–11.8) 1.2 (1.0–3.2) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 4.2 (2.9–6.1) 

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Table 8

Incidence of permanent harm (including death) after CNB with ‘optimistic’ (see text for explanation) interpretation of data: events per 100 000 cases (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot’ phase of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 8.2 (3.5–16.1) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 3.1 (1.4–5.8) 
Spinal 1.6 (1.0–4.6) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.9 (0–2.7) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 4.2 (2.2–7.1) 0.3 (0–1.7) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 2.0 (1.1–3.3) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 8.2 (3.5–16.1) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 3.1 (1.4–5.8) 
Spinal 1.6 (1.0–4.6) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.9 (0–2.7) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 4.2 (2.2–7.1) 0.3 (0–1.7) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 2.0 (1.1–3.3) 

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Table 8

Incidence of permanent harm (including death) after CNB with ‘optimistic’ (see text for explanation) interpretation of data: events per 100 000 cases (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot’ phase of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 8.2 (3.5–16.1) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 3.1 (1.4–5.8) 
Spinal 1.6 (1.0–4.6) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.9 (0–2.7) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 4.2 (2.2–7.1) 0.3 (0–1.7) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 2.0 (1.1–3.3) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 8.2 (3.5–16.1) 0.6 (0–3.4) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 3.1 (1.4–5.8) 
Spinal 1.6 (1.0–4.6) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.9 (0–2.7) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 4.2 (2.2–7.1) 0.3 (0–1.7) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 2.0 (1.1–3.3) 

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Table 9

Incidence of paraplegia or death after CNB with ‘pessimistic’ (see text for explanation) interpretation of data: events per 100 000 (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot’ phase of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 6.1 (2.2–13.3) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 2.0 (1.0–4.5) 
Spinal 2.1 (1.0–5.4) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 1.2 (1.0–3.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 3.8 (2.0–6.7) 0 (0–0.9) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 1.8 (1.0–3.1) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 6.1 (2.2–13.3) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 2.0 (1.0–4.5) 
Spinal 2.1 (1.0–5.4) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 1.2 (1.0–3.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 3.8 (2.0–6.7) 0 (0–0.9) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 1.8 (1.0–3.1) 

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Table 9

Incidence of paraplegia or death after CNB with ‘pessimistic’ (see text for explanation) interpretation of data: events per 100 000 (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot’ phase of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 6.1 (2.2–13.3) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 2.0 (1.0–4.5) 
Spinal 2.1 (1.0–5.4) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 1.2 (1.0–3.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 3.8 (2.0–6.7) 0 (0–0.9) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 1.8 (1.0–3.1) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 6.1 (2.2–13.3) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 2.0 (1.0–4.5) 
Spinal 2.1 (1.0–5.4) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 1.2 (1.0–3.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1.0–17.3) 
Caudal 0 (0–33.3) N/A 8.8 (1.0–49.0) 0 (0–16.6) 0 (0–32.8) 2.1 (1.0–11.7) 
Total 3.8 (2.0–6.7) 0 (0–0.9) 2.5 (1.0–13.7) 0 (0–13.9) 0 (0–24.2) 1.8 (1.0–3.1) 

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Table 10

Incidence of paraplegia or death after CNB with ‘optimistic’ (see text for explanation) interpretation of data: events per 100 000 (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot phase’ of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 1.0 (1.0–5.7) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 0.3 (0–1.9) 
Spinal 1.1 (1.0–3.8) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.6 (0–2.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 1.6 (1.0–3.7) 0 (0–0.9) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 0.7 (0–1.6) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 1.0 (1.0–5.7) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 0.3 (0–1.9) 
Spinal 1.1 (1.0–3.8) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.6 (0–2.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 1.6 (1.0–3.7) 0 (0–0.9) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 0.7 (0–1.6) 

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Table 10

Incidence of paraplegia or death after CNB with ‘optimistic’ (see text for explanation) interpretation of data: events per 100 000 (95% CI). N/A, zero denominator (i.e. no cases reported in this group in the ‘snapshot phase’ of the project)

Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 1.0 (1.0–5.7) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 0.3 (0–1.9) 
Spinal 1.1 (1.0–3.8) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.6 (0–2.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 1.6 (1.0–3.7) 0 (0–0.9) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 0.7 (0–1.6) 
Perioperative . Obstetric . Chronic pain . Paediatric . Non-anaesthetists . Sum . 
Epidural 1.0 (1.0–5.7) 0 (0–1.9) 0 (0–10.7) 0 (0–95.9) 0 (0–121.1) 0.3 (0–1.9) 
Spinal 1.1 (1.0–3.8) 0 (0–2.2) 0 (0–226.1) 0 (0–921.8) 0 (0–386.6) 0.6 (0–2.2) 
CSE 12.1 (1.5–43.7) 0 (0–11.8) N/A N/A N/A 4.8 (1–17.3) 
Caudal 0 (0–33.3) N/A 0 (0–26.3) 0 (0–16.6) 0 (0–32.8) 0 (0–6.3) 
Total 1.6 (1.0–3.7) 0 (0–0.9) 0 (0–7.4) 0 (0–13.9) 0 (0–24.2) 0.7 (0–1.6) 

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Paraplegia and death are the worst possible outcomes so figures for these (13 ‘pessimistic’ and five ‘optimistic’) were extracted and analysed in the same way. The overall incidence of these two complications in this series is ‘pessimistically’ 1.8 per 100 000 (95% CI 1.0–3.1; 1 in 54 500) and ‘optimistically’ 0.7 in 100 000 (95% CI 0–1.6; 1 in 141 500) (Tables 9 and 10). The patterns revealed are similar to those seen in the analysis of all permanent complications.

Six patient deaths were reported (two abscesses, three cardiovascular collapses, and one wrong route error). All were included in the ‘pessimistic’ assessment, giving a rate of <1 in 100 000 (0.8 per 100 000: 95% CI 0–1.8), and three in the ‘optimistic’ group, a rate of <1 in 200 000 (0.4 per 100 000: 95% CI 0–1.2). Four of the deaths were considered to be directly associated with CNB and two indirectly.

Consideration of the cases with a fatal outcome (Table 11) may clarify how determinations of ‘pessimistic’ and ‘optimistic’ decisions were made, and illustrate the need to present the outcome data in both ways.

Table 11

Case summaries of deaths due to CNB

Death 1 A middle-aged patient with locally advanced and metastatic malignancy underwent a very prolonged urological procedure under spinal anaesthetic. No senior anaesthetist was present. Moderate hypotension progressed to profound hypotension with no recordable arterial pressure. Attempted resuscitation, involving senior members of staff, was unsuccessful. The death certificate recorded acute myocardial infarction as the cause of death. The case was included in the pessimistic and optimistic incidences and death was considered a direct complication of CNB 
Death 2 A very elderly frail patient had a joint arthroplasty performed under CSE and was nursed on ICU after operation. During a period of hypotension, a large volume of bupivacaine was inadvertently administered i.v. The patient developed pulseless electrical activity and prolonged resuscitation failed. An inquest recorded a verdict of accidental death. The case was included in the pessimistic and the optimistic incidence of permanent harm. Death was considered a direct complication of CNB 
Death 3 A healthy elderly patient underwent a lower limb arthroplasty. The epidural component of a CSE was complicated by an inadvertent dural tap. Anaesthesia was uneventful. A low-dose local anaesthetic infusion was commenced via the epidural catheter and several hours later, the patient was found in cardiac arrest. Routine observations had not been performed for several hours. The patient was resuscitated and admitted to ICU, but major neurological damage was evident and the patient died several weeks later. The case was included in the pessimistic and optimistic incidence and death was considered a direct complication of CNB 
Death 4 An unfit elderly patient was due to undergo repair of a fractured neck of femur. Spinal anaesthesia was performed. Approximately 12 min later, the patient collapsed and resuscitation was unsuccessful. Information on this case was grossly incomplete. There was also uncertainty as to what led to the patient's death: potential causes included drug allergy, thromboembolic, or fat embolus and complications related to the spinal anaesthetic. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered a direct complication of CNB 
Death 5 An elderly unfit patient underwent a caudal injection for chronic back pain. Recovery was uneventful. Several days later the patient presented with sepsis, and an epidural abscess (distant from the procedure site) was identified. ‘Unrelated complications during hospital admission’ led to ICU admission. The patient made a good recovery from these, but then suffered an unexpected fatal cardiac arrest. The chain of events that culminated in patient death started with the caudal block, but the chain of causation is far from clear. The case was included in the pessimistic and excluded from the optimistic incidence of permanent harm. Death was considered an indirect complication of CNB 
Death 6 An elderly patient with multiple medical co-morbidities and immunosuppression was admitted to ICU after a respiratory arrest. The patient had vertebral collapse and uncontrollable back pain. Use of parenteral opioid analgesia before ICU admission had led to pneumonia and respiratory arrest. After discussion, an epidural was inserted leading to good analgesia. Within 24 h, the patient developed leg weakness and subsequent investigation identified an epidural abscess. Surgery was offered and declined. The patient developed paraplegia and was discharged, wheelchair-bound, at 6 months. The patient died an indeterminate period of time later. There was doubt as to whether the abscess pre-existed the epidural. There was also uncertainty as to what led to the patient's death. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered an indirect complication of CNB 
Death 1 A middle-aged patient with locally advanced and metastatic malignancy underwent a very prolonged urological procedure under spinal anaesthetic. No senior anaesthetist was present. Moderate hypotension progressed to profound hypotension with no recordable arterial pressure. Attempted resuscitation, involving senior members of staff, was unsuccessful. The death certificate recorded acute myocardial infarction as the cause of death. The case was included in the pessimistic and optimistic incidences and death was considered a direct complication of CNB 
Death 2 A very elderly frail patient had a joint arthroplasty performed under CSE and was nursed on ICU after operation. During a period of hypotension, a large volume of bupivacaine was inadvertently administered i.v. The patient developed pulseless electrical activity and prolonged resuscitation failed. An inquest recorded a verdict of accidental death. The case was included in the pessimistic and the optimistic incidence of permanent harm. Death was considered a direct complication of CNB 
Death 3 A healthy elderly patient underwent a lower limb arthroplasty. The epidural component of a CSE was complicated by an inadvertent dural tap. Anaesthesia was uneventful. A low-dose local anaesthetic infusion was commenced via the epidural catheter and several hours later, the patient was found in cardiac arrest. Routine observations had not been performed for several hours. The patient was resuscitated and admitted to ICU, but major neurological damage was evident and the patient died several weeks later. The case was included in the pessimistic and optimistic incidence and death was considered a direct complication of CNB 
Death 4 An unfit elderly patient was due to undergo repair of a fractured neck of femur. Spinal anaesthesia was performed. Approximately 12 min later, the patient collapsed and resuscitation was unsuccessful. Information on this case was grossly incomplete. There was also uncertainty as to what led to the patient's death: potential causes included drug allergy, thromboembolic, or fat embolus and complications related to the spinal anaesthetic. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered a direct complication of CNB 
Death 5 An elderly unfit patient underwent a caudal injection for chronic back pain. Recovery was uneventful. Several days later the patient presented with sepsis, and an epidural abscess (distant from the procedure site) was identified. ‘Unrelated complications during hospital admission’ led to ICU admission. The patient made a good recovery from these, but then suffered an unexpected fatal cardiac arrest. The chain of events that culminated in patient death started with the caudal block, but the chain of causation is far from clear. The case was included in the pessimistic and excluded from the optimistic incidence of permanent harm. Death was considered an indirect complication of CNB 
Death 6 An elderly patient with multiple medical co-morbidities and immunosuppression was admitted to ICU after a respiratory arrest. The patient had vertebral collapse and uncontrollable back pain. Use of parenteral opioid analgesia before ICU admission had led to pneumonia and respiratory arrest. After discussion, an epidural was inserted leading to good analgesia. Within 24 h, the patient developed leg weakness and subsequent investigation identified an epidural abscess. Surgery was offered and declined. The patient developed paraplegia and was discharged, wheelchair-bound, at 6 months. The patient died an indeterminate period of time later. There was doubt as to whether the abscess pre-existed the epidural. There was also uncertainty as to what led to the patient's death. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered an indirect complication of CNB 

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Table 11

Case summaries of deaths due to CNB

Death 1 A middle-aged patient with locally advanced and metastatic malignancy underwent a very prolonged urological procedure under spinal anaesthetic. No senior anaesthetist was present. Moderate hypotension progressed to profound hypotension with no recordable arterial pressure. Attempted resuscitation, involving senior members of staff, was unsuccessful. The death certificate recorded acute myocardial infarction as the cause of death. The case was included in the pessimistic and optimistic incidences and death was considered a direct complication of CNB 
Death 2 A very elderly frail patient had a joint arthroplasty performed under CSE and was nursed on ICU after operation. During a period of hypotension, a large volume of bupivacaine was inadvertently administered i.v. The patient developed pulseless electrical activity and prolonged resuscitation failed. An inquest recorded a verdict of accidental death. The case was included in the pessimistic and the optimistic incidence of permanent harm. Death was considered a direct complication of CNB 
Death 3 A healthy elderly patient underwent a lower limb arthroplasty. The epidural component of a CSE was complicated by an inadvertent dural tap. Anaesthesia was uneventful. A low-dose local anaesthetic infusion was commenced via the epidural catheter and several hours later, the patient was found in cardiac arrest. Routine observations had not been performed for several hours. The patient was resuscitated and admitted to ICU, but major neurological damage was evident and the patient died several weeks later. The case was included in the pessimistic and optimistic incidence and death was considered a direct complication of CNB 
Death 4 An unfit elderly patient was due to undergo repair of a fractured neck of femur. Spinal anaesthesia was performed. Approximately 12 min later, the patient collapsed and resuscitation was unsuccessful. Information on this case was grossly incomplete. There was also uncertainty as to what led to the patient's death: potential causes included drug allergy, thromboembolic, or fat embolus and complications related to the spinal anaesthetic. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered a direct complication of CNB 
Death 5 An elderly unfit patient underwent a caudal injection for chronic back pain. Recovery was uneventful. Several days later the patient presented with sepsis, and an epidural abscess (distant from the procedure site) was identified. ‘Unrelated complications during hospital admission’ led to ICU admission. The patient made a good recovery from these, but then suffered an unexpected fatal cardiac arrest. The chain of events that culminated in patient death started with the caudal block, but the chain of causation is far from clear. The case was included in the pessimistic and excluded from the optimistic incidence of permanent harm. Death was considered an indirect complication of CNB 
Death 6 An elderly patient with multiple medical co-morbidities and immunosuppression was admitted to ICU after a respiratory arrest. The patient had vertebral collapse and uncontrollable back pain. Use of parenteral opioid analgesia before ICU admission had led to pneumonia and respiratory arrest. After discussion, an epidural was inserted leading to good analgesia. Within 24 h, the patient developed leg weakness and subsequent investigation identified an epidural abscess. Surgery was offered and declined. The patient developed paraplegia and was discharged, wheelchair-bound, at 6 months. The patient died an indeterminate period of time later. There was doubt as to whether the abscess pre-existed the epidural. There was also uncertainty as to what led to the patient's death. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered an indirect complication of CNB 
Death 1 A middle-aged patient with locally advanced and metastatic malignancy underwent a very prolonged urological procedure under spinal anaesthetic. No senior anaesthetist was present. Moderate hypotension progressed to profound hypotension with no recordable arterial pressure. Attempted resuscitation, involving senior members of staff, was unsuccessful. The death certificate recorded acute myocardial infarction as the cause of death. The case was included in the pessimistic and optimistic incidences and death was considered a direct complication of CNB 
Death 2 A very elderly frail patient had a joint arthroplasty performed under CSE and was nursed on ICU after operation. During a period of hypotension, a large volume of bupivacaine was inadvertently administered i.v. The patient developed pulseless electrical activity and prolonged resuscitation failed. An inquest recorded a verdict of accidental death. The case was included in the pessimistic and the optimistic incidence of permanent harm. Death was considered a direct complication of CNB 
Death 3 A healthy elderly patient underwent a lower limb arthroplasty. The epidural component of a CSE was complicated by an inadvertent dural tap. Anaesthesia was uneventful. A low-dose local anaesthetic infusion was commenced via the epidural catheter and several hours later, the patient was found in cardiac arrest. Routine observations had not been performed for several hours. The patient was resuscitated and admitted to ICU, but major neurological damage was evident and the patient died several weeks later. The case was included in the pessimistic and optimistic incidence and death was considered a direct complication of CNB 
Death 4 An unfit elderly patient was due to undergo repair of a fractured neck of femur. Spinal anaesthesia was performed. Approximately 12 min later, the patient collapsed and resuscitation was unsuccessful. Information on this case was grossly incomplete. There was also uncertainty as to what led to the patient's death: potential causes included drug allergy, thromboembolic, or fat embolus and complications related to the spinal anaesthetic. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered a direct complication of CNB 
Death 5 An elderly unfit patient underwent a caudal injection for chronic back pain. Recovery was uneventful. Several days later the patient presented with sepsis, and an epidural abscess (distant from the procedure site) was identified. ‘Unrelated complications during hospital admission’ led to ICU admission. The patient made a good recovery from these, but then suffered an unexpected fatal cardiac arrest. The chain of events that culminated in patient death started with the caudal block, but the chain of causation is far from clear. The case was included in the pessimistic and excluded from the optimistic incidence of permanent harm. Death was considered an indirect complication of CNB 
Death 6 An elderly patient with multiple medical co-morbidities and immunosuppression was admitted to ICU after a respiratory arrest. The patient had vertebral collapse and uncontrollable back pain. Use of parenteral opioid analgesia before ICU admission had led to pneumonia and respiratory arrest. After discussion, an epidural was inserted leading to good analgesia. Within 24 h, the patient developed leg weakness and subsequent investigation identified an epidural abscess. Surgery was offered and declined. The patient developed paraplegia and was discharged, wheelchair-bound, at 6 months. The patient died an indeterminate period of time later. There was doubt as to whether the abscess pre-existed the epidural. There was also uncertainty as to what led to the patient's death. The case was included in the pessimistic incidence and excluded from the optimistic incidence. Death was considered an indirect complication of CNB 

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We followed the progress of those patients reported to the project with an initially serious neurological injury in whom we were able to determine a final outcome (Table 12). Patients were included even if they did not meet inclusion criteria (e.g. incidents occurring outside the audit dates or in private hospitals).

Table 12

Prognosis, at 6 months, of all significant injuries with early neurological injury after CNB: numbers (%). Cases include those occurring after CNB performed outside the audit period or in non-NHS hospitals. Immediately fatal cases are not included

Cases reported with initial neurological impairment . Major improvement . No or minimal improvement . 
Ischaemia 0 (0) 5 (100) 
Abscess 12 7 (58) 5 (42) 
Nerve injury 13 9 (69) 4 (31) 
Meningitis 3 (100) 0 (0) 
Vertebral canal haematoma 6 (75) 2 (25) 
Total 41 25 (61) 16 (39) 
Cases reported with initial neurological impairment . Major improvement . No or minimal improvement . 
Ischaemia 0 (0) 5 (100) 
Abscess 12 7 (58) 5 (42) 
Nerve injury 13 9 (69) 4 (31) 
Meningitis 3 (100) 0 (0) 
Vertebral canal haematoma 6 (75) 2 (25) 
Total 41 25 (61) 16 (39) 

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Table 12

Prognosis, at 6 months, of all significant injuries with early neurological injury after CNB: numbers (%). Cases include those occurring after CNB performed outside the audit period or in non-NHS hospitals. Immediately fatal cases are not included

Cases reported with initial neurological impairment . Major improvement . No or minimal improvement . 
Ischaemia 0 (0) 5 (100) 
Abscess 12 7 (58) 5 (42) 
Nerve injury 13 9 (69) 4 (31) 
Meningitis 3 (100) 0 (0) 
Vertebral canal haematoma 6 (75) 2 (25) 
Total 41 25 (61) 16 (39) 
Cases reported with initial neurological impairment . Major improvement . No or minimal improvement . 
Ischaemia 0 (0) 5 (100) 
Abscess 12 7 (58) 5 (42) 
Nerve injury 13 9 (69) 4 (31) 
Meningitis 3 (100) 0 (0) 
Vertebral canal haematoma 6 (75) 2 (25) 
Total 41 25 (61) 16 (39) 

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Discussion

The results of this large prospective project are largely reassuring with the incidence of permanent injury being lower than in other equivalent or related studies.18,22–24 Assessed ‘pessimistically’ the incidence of permanent injury after CNB was 4.2 per 100 000, and of paraplegia/death was 1.8 per 100 000. ‘Optimistically’ the incidence of permanent injury was 2.0 per 100 000 and of paraplegia/death 0.7 per 100 000. The incidence of complications of epidural and CSE were at least twice those of spinals and caudals.

Previous studies have focused on the neurological complications of CNB, but this project took a broader approach and included all major complications of CNB, whether leading to neurological or other major sequelae. As a result, several deaths and major complications from wrong route errors or cardiovascular collapse were identified.

An internal NPSA paper describes epidural anaesthesia and its multiple potential complications well: ‘a complex amalgam of clinical judgement, technical skills, materials and equipment, drug delivery systems, patient supervision and care pathways. In addition to inherent complications in the procedure, each of these facets has the potential to generate patient harm through a combination of patient characteristics, human error or shortfalls in performance, equipment dysfunction and broader system failures. As a consequence, an enormous number of injuries can result’.25 This description is applicable to all forms of CNB and encapsulates the complexity of these seemingly simple procedures. The results of this national project reflect the complexities of both CNB and the interpretation of its sequelae.

Data interpretation

The data contain both clinical uncertainty and statistical uncertainty. We have presented the results in both ‘pessimistic’ and ‘optimistic’ terms to acknowledge the clinical uncertainty. As the case descriptions of the patients who died illustrate, in many cases, the interpretation of clinical descriptions was difficult because causation may be uncertain within a complex train of events. In other cases, the degree to which CNB led to final outcome may be uncertain. As an example we do not know whether spinal cord ischaemia after general anaesthesia in elderly frail patients who also have an epidural in place is caused by the CNB or simply coincidental: there were four such cases. Further, the final outcome was not always clear. One option would have been to be more decisive and simply present one ‘best guess’ result, but this would be an inappropriately simplistic response to the reality of complex clinical data. In 11 of 84 cases, interpretation was hampered by incomplete information: gaps were interpreted pessimistically even though this may mean that some patients were included inappropriately.

The statistical uncertainty is accommodated by the use of 95% confidence intervals (CIs) for all calculated incidences. In many cases, CIs are large, an inevitable consequence of the low or zero numerators of some groups. The data with the narrowest CIs are those with larger numerators and large denominators. Data with low or zero numerators are difficult to interpret.26,27 For zero numerators, we used the recommended ‘rule of 3’ (which states that for n observations with a zero numerator, the upper 95% confidence limit is 3/n) to calculate the upper confidence limit.26 The importance of this is that the main results have quite narrow CIs (e.g. pessimistic incidence of permanent injury from any CNB; 4.2 per 100 000 cases, 95% CI 2.9–6.1). In contrast, some of the sub-classifications of the data have very wide CIs (e.g. optimistic incidence of death or paraplegia after spinal anaesthesia in children 0 per 100 000 cases, 95% CI 0–921.8). This makes such data, particularly those with zero numerators, very difficult to interpret, and we would advise extreme caution in doing so.

The nature of this project means that whatever incidence is calculated from our data, it can only be a minimum incidence: unreported or wrongly excluded cases would increase the rates. Each additional case would increase the pessimistic incidence by ∼3%.

Data reliability and validation

The first and most obvious question is, ‘are the results robust?’ We consider the denominator(s) to be robust because they are based on a census of activity of the entire relevant population not a sample. All UK NHS hospitals committed to the project and all returned census data with more than 92% of these data being reported as ‘accurate’. Therefore, any error in the denominator is small.

Within the numerator data, there are both ‘known unknowns’ and ‘unknown unknowns’.28 The known unknowns are those cases which were reported, but where detail was inadequate for robust decisions on the nature or outcome of the event. In 11 cases (13%), insufficient information prevented determination of long-term outcome: in each, no recovery was assumed. Therefore, several cases have been classified ‘pessimistically’ as suffering permanent injury when full recovery may have occurred: this will have increased the resulting incidence of such complications. The unknown unknowns are those cases which may exist, but were not notified and therefore have not been included in incidence calculations. Inevitably, it is impossible to determine their number and futile to speculate on numbers, but every effort was made to disseminate widely information about the project, both within and outside the anaesthetic speciality. That 100% of hospitals volunteered an LR to the project, 100% returned census data, and more than 10% of cases were notified by non-anaesthetists attests to wide awareness and enthusiasm for the project.

Several sources were searched in an effort to validate the denominator (the number of procedures performed annually) and numerator (the number of relevant complications). These sources were either incomplete, from different populations, not validated themselves, or were impossible to correlate with the data presented here. None of the sources searched provided any information which conflicted with this project's data. Validation attempts showed that most cases of significant injury after CNB had not been notified to other national databases of clinical incident (e.g. NRLS). This raises concerns over the current under reporting of serious clinical incidents to the NRLS. It is, however, recognized that a number of data sources are required to fully capture and characterize clinical incidents.29 In contrast, validation attempts only identified one case that had, at that time, definitely not been reported to us and we subsequently learned of this case by other means also.

In spite of the inability to validate data externally, comparisons are possible with other data published recently. A UK audit of more than 10 000 paediatric epidurals reported a similarly low number of major complications, no deaths, and a permanent neurological injury incidence of 1 in 10 663,30 and thus is consistent with this survey. A survey of UK hospitals by Meikle and colleagues,31 identified knowledge of 40 vertebral canal haematomas occurring in a 6 yr period. Their annual rate of seven cases per year is very similar to that of this project: eight cases of vertebral canal haematoma were reported in 1 yr, with five meeting full inclusion criteria. In a Canadian series, the rate of decompressive laminectomy was 21 per 100 000 cases.32 In our equivalent subgroup (adult, non-obstetric perioperative epidurals), the incidence of decompressive laminectomy was 12.3 per 100 000: within the confidence limits of the Canadian data. It should be noted that Canadian and UK practice in selecting patients for laminectomy may well differ and our cohort contains nine cases which might have undergone laminectomy if the threshold for it was lower.

Comparison with other studies

The burden of neurological complications from CNB compared with other causes such as general anaesthesia and surgery is not well reported. A recent review of 54 cases from a UK medical defence organization found 72% were ‘surgical’ and 28% ‘non-surgical’.33 This, somewhat limited report indicates that neurological injury associated with regional anaesthesia is much less frequent than that related to surgery. Further, the incidence of such injury may differ little between regional and general anaesthesia.34

The best information available previously on major complications after regional anaesthesia comes from surveys in two Scandinavian countries, Finland and Sweden, both having ‘no fault’ compensation schemes and populations small enough to allow for central reporting systems. In Finland, a survey of 720 000 procedures performed between 1987 and 1993 found that the incidence of major complications was one in 22 000 after spinal anaesthesia and one in 19 000 after epidural block.22 In Sweden, a survey of 1.7 million procedures performed between 1990 and 1999 found an incidence of severe neurological complications of one in 20 000–30 000 after spinal anaesthesia, one in 25 000 after obstetric epidural, and one in 3600 after non-obstetric epidural.23 Both reviews were retrospective.

In the UK, Christie and McCabe18 retrospectively recorded 12 major complications after 8100 perioperative epidurals (1 in 675) in one hospital. This approximates to 148 per 100 000 epidurals. As nine patients made a full recovery, permanent injury was three in 8100 (37 per 100 000, 95% CI 7.6–108). Our point estimates for permanent injury after adult perioperative epidural are: pessimistic 17.4 per 100 000 (95% CI 7.2–27.8) and optimistic 8.2 per 100 000 (95% CI 3.5–16). Although the CIs from these data are narrower than those of Christie and McCabe, there is significant overlap. The figures reported here come from a population some 12 times larger so that the point estimates and CIs are likely to be more robust.

Cameron and colleagues35 reported a similar, retrospective, single hospital series, from Australia. Two vertebral canal haematomas and six epidural abscesses followed 8210 ‘acute pain’ epidurals. One laminectomy was required and there were no cases of permanent neurological injury. The incidences of vertebral canal haematoma (24 per 100 000, 95% CI 3–88), abscess (73 per 100 000, 95% CI 27–159), laminectomy (12 per 100 000, 95% CI 1–68), and permanent neurological harm (0 in 100 000, 95% CI 0–45) are again broadly consistent with those reported here.

Clinical implications

In the current series, as in the Swedish study, most complications of CNB occurred when epidural block was used in the perioperative period. Whether this was because it was used in higher risk patients is not something that this project can identify, but a higher (or lower) incidence of complications in one subgroup does not necessarily equate to the procedure being less (or more) appropriate for them. There are both statistical and clinical reasons for this. First, Moen and colleagues’23 figure of one in 1800 major complications in women having epidural anaesthesia for knee arthroplasty is often quoted, but the absence of any complications in men having the same procedure for hip arthroplasty or spinal anaesthetic for knee arthroplasty is rarely mentioned. Denominators for these groups were as low as 7000 and are too small for robust point estimates of incidences.

Secondly, the clinical perspective of the appropriateness or safety of a CNB procedure must recognize the potential benefits of that procedure (compared with other techniques) and risks other than the major ones reported here. Such risk–benefit analyses will differ between subgroups of patients and procedures so, for both statistical and clinical reasons, comparisons between subgroups should be made with considerable caution.

The patient characteristics are also relevant. More complications were reported in females than in males, but permanent injury was of equal incidence. Although many patients experiencing complications were aged >70 yr, a significant proportion was <50 yr of age (Table 5). More than half of the patients were fit and well (estimated ASA grades I–II), and most patients were undergoing major, elective surgery with CNB being performed by consultants. However, denominator data for these observations were not collected, so the extent (if any), to which these factors are associated with, or causal of, adverse outcomes cannot be determined. Notwithstanding this, patients who developed spinal cord ischaemia, vertebral canal haematoma, and epidural abscess were usually elderly, many were infirm and most undergoing major surgery. In contrast, patients suffering (non-ischaemic) nerve injury were more frequently young and healthy. These differences reinforce that comparisons between subgroups may not be valid.

Accepting these cautions, several clinical findings are of note. More complications occurred with perioperative epidural than in any other subgroup, although the four perioperative deaths all occurred in association with spinal or CSE block. Obstetric, chronic pain, and paediatric groups had a low incidence of major complications. This series includes one of the largest cohorts of each subgroup and, as such, those results are reassuring.

Concerns have been raised previously about the safety of CSE,36–38 and in this series, it had a relatively high incidence of complications. It represented only 5.9% of all CNBs performed, but led to 13–14% of permanent injuries and 15–40% of cases of paraplegia/death. Two of the deaths followed its use.

Of perhaps greater concern is the continuing problem with ‘wrong route’ injection errors: nine cases are reported here, six in obstetric practice. There was one death, but no other patient harm. A further similar death occurred in an obstetric unit shortly before this audit started:16 judged by the coroner to be an ‘unlawful killing’.39 Subsequently, an NPSA-published safety alert20 and multi-professional best practice guidance40 have highlighted the problem and identified measures to reduce its occurrence. That one in four respondents to a recent survey of 206 UK obstetric units reported knowledge of such an event indicates that this may be a major problem.41 Several alternatives, to remedy these potentially fatal mix-ups, have been advocated, but until a robust solution is universally in place, these events are likely to continue. This might be termed a national ‘systems error’. It is beyond the remit of this review to evaluate solutions, but clearly one must be found.

Prognosis of neurological complications

Most reviews of serious complications of CNB do not report their prognosis. All major complications are important, but the incidence of permanent harm is the most critical outcome. In Christie's series, three-quarters of identified patients made a full recovery. In this project, it was possible to monitor the progress of 41 initially major neurological complications of CNB (Table 12), and in 25 (61%) complete, or almost complete, recovery was documented. Neurological injury associated with spinal cord ischaemia or vertebral canal haematoma had a notably poor prognosis, whereas all patients with meningitis and the majority of patients experiencing nerve injury and abscess recovered fully. As we did not set out to identify all mild or moderate complications of CNB, unreported minor cases will have occurred and some may have resulted in permanent harm.

Overview

This project attempted to identify the incidence of major complications resulting in permanent harm after CNB in NHS hospitals in the UK. The number of such procedures was estimated in a 2 week census, and the complications of all CNBs performed over 1 yr in the NHS were identified, followed up, and analysed in detail. Analysis of the data suggests a lower incidence than reported previously in other series, usually of smaller numbers of patients, but there can be no certainty that all relevant cases were identified. There would need to be a considerable number of additional cases for the results of this project to be changed significantly, but if anyone is aware of such an unreported case meeting the inclusion requirements (see Methods section), the review panel would welcome further reports (in confidence to Professor Wildsmith at [email protected]). If a substantial number of reports is made, the results will be updated in the future.

Funding

The project was funded by The Royal College of Anaesthetists. It would not have been possible without time and support given freely by many individuals and organizations.

Acknowledgements

First, our thanks go to the network of local reporters who collected the data for this project and supplied the detailed clinical reports, as well as the other individuals who notified us of cases. The following organizations were represented at a preliminary meeting and their unanimous support contributed to the development and success of the project: Association of Anaesthetists of Great Britain and Ireland (Professor Mike Harmer), British Pain Society (Dr Beverley Collett and Dr Andrew Vickers), European Society of Regional Anaesthesia, Great Britain and Ireland Section (Dr Barrie Fischer), National Confidential Acute Pain Critical Incident Audit (Dr David Counsell), Patient Liaison Group of the Royal College of Anaesthetists (Mrs Anne Murray), Acute Pain Nurses (Ms Sharon Kitkatt), National Patient Safety Agency (Mrs Joan Russell), Council of the Royal College of Anaesthetists (Dr Anne May, Professor Tony Wildsmith). We are also indebted to the President, Council, and the Head of Professional Standards (Mr Charlie McLaughlan) at the Royal College of Anaesthetists. We would also like to acknowledge the advice of Mrs Karen Thomson, Patient Information Advisory Group at the Department of Health and Ms Alexandra Cronberg, statistician at the National Patient Safety Agency. Finally, special thanks go to the chief administrator for the project at the Royal College of Anaesthetists, Ms Shirani Nadarajah.

Appendix 1: supporting organizations

The project was endorsed by the following organizations and specialist societies which played an important role in the promotion and dissemination of information about the project: Association of Anaesthetists of Great Britain and Ireland, Association of British Neurologists, Association of Paediatric Anaesthetists, British Association of Spinal Surgeons, British Pain Society, British Society of Neuroradiologists, European Society of Regional Anaesthesia (Great Britain and Ireland Section), Medical Defence Union, Medical Protection Society, National Confidential Acute Pain Critical Incident Audit, National Patient Safety Agency, Obstetric Anaesthetists Association, Royal College of Radiologists, and Society of British Neurological Surgeons. The project was also endorsed by the Chief Medical Officers of England (Sir Liam Donaldson), Northern Ireland (Dr Elizabeth Mitchell), Scotland (Dr Harry Burns), and Wales (Dr David Salter).

Appendix 2: the review panel

The review panel was composed of experts in CNB and its complications, as follows (in alphabetical order with their nominating groups): Dr David Bogod (Obstetric Anaesthetists Association), Dr Iain Christie (Association of Anaesthetists of Great Britain and Ireland), Dr David Counsell (National Confidential Acute Pain Critical Incident Audit), Dr Max Damian (Association of British Neurologists), Dr Barrie Fischer (European Society of Regional Anaesthesia: Great Britain and Ireland Section), Dr Richard Howard (Association of Paediatric Anaesthetists), Professor Ravi Mahajan (Royal College of Anaesthetists), Dr Angelique Mastihi (Medical Protection Society), Mrs Anne Murray (Patient Liaison Group, Royal College of Anaesthetists), Mrs Joan Russell (National Patient Safety Agency), Dr Nick Scott (European Society of Regional Anaesthesia: Great Britain and Ireland Section), Dr Andrew Vickers (British Pain Society), Professor Tony Wildsmith (Royal College of Anaesthetists). Several panel members also brought medico-legal expertise to the review panel. The panel was chaired by Dr Tim Cook (Project Lead, Royal College of Anaesthetists) who obtained additional expertise, as required, from individuals nominated by specialist microbiological or radiological organizations.

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Sours: https://academic.oup.com/bja/article/102/2/179/304479

Regional Anesthetic Blocks

Continuing Education Activity

A regional block is a specific anesthetic technique that inhibits nerve transmission to avoid or relieve pain. This activity reviews the indications, contraindications, complications, and other key elements related to the essential points needed by members of an interprofessional team managing the care of patients undergoing surgical procedures.

Objectives:

  • Review the indications for using regional blocks.

  • Describe the equipment, personnel, preparation, and technique in regards to regional blocks.

  • Outline the potential complications and their clinical significance when using regional blocks.

  • Summarize interprofessional team strategies for improving care coordination and communication to advance regional block performance and improve outcomes.

Access free multiple choice questions on this topic.

Introduction

Regional anesthesia consists of infiltrating a peripheral nerve with an anesthetic agent and blocking transmission to avoid or relieve pain. It differs from general anesthesia as it does not affect the patient's consciousness level to relieve pain. There are several advantages over general anesthesia, such as avoidance of airway manipulation, reduced doses, side effects of systemic drugs, faster recovery time, and significantly lower pain levels after surgery.[1]

Postprocedural recovery time has shown to be reduced with markedly lower pain levels after surgery and earlier participation in physical therapy. Regional anesthesia can be used in conjunction with general anesthesia, postprocedural, and often for many acute and chronic pain conditions.

Anatomy and Physiology

Anatomy and landmarks depend on the different types of blocks being performed.

For neuraxial anesthesia, medication (local anesthetic, opioids, etc.) is injected near the central nervous system's nerves. This is performed with techniques by directly injecting into the spinal cord's epidural space or subarachnoid space. The most common neuraxial techniques are epidural, spinal, and combined spinal-epidural. For spinal anesthesia, a needle is placed between the lumbar vertebrae, usually at the level of approximately L4-L5 (conus medularis ends at approximately L1/L2 in adults); the needle is then advanced through the supraspinal ligament, interspinal ligament, and ligamentum flavum until it reaches the subarachnoid space where the medication (local anesthetic with/without opioid) is injected. For epidural anesthesia, a needle is placed between vertebrae (may be cervical, thoracic, or lumbar) passing through the spinal ligaments to reach the epidural space just outside the subarachnoid space.

For peripheral nerve blocks, the local anesthetic agent is injected near the nerve and diffuses along with the nerve's mantle layer to the core. Anesthesia is achieved slowly after infiltration in a proximal to distal direction on the nerve distribution to the injection point.

A type of intravenous regional anesthesia, also called Bier block, is also used to inject an intravenous local anesthetic medication at the most distal venous portion of a lower or upper extremity. The anesthetized limb has a tourniquet to avoid the spread of the anesthetic agent to the systemic circulation. With the advancement in regional techniques and ultrasound-guided blocks, intravenous regional anesthesia is rarely used.

Indications

The use of regional anesthesia has widely been implemented among anesthesiologists and pain providers. It requires training and in-depth knowledge of anatomy.

Whether to perform a regional block depends on the type of procedure, patient's characteristics, and anesthesiologist's preferences. Some of the indications are to avoid side effects of general anesthetic medications (like respiratory depression), postoperative pain control, and to treat certain chronic pain conditions.[2]

The main types of regional anesthesia are

  1. Neuraxial anesthesia (spinal anesthesia and epidural anesthesia) 

  2. Peripheral nerve blocks

  3. Intravenous regional anesthesia

Contraindications

Absolute contraindications to the use of regional anesthesia include:

  • The patient's refusal

  • Allergy to local anesthetics

Relative contraindications are:

  • Active infection at the site of the injection

  • Patients with coagulopathies

  • Preexisting neurologic deficit

  • Inability to cooperate[2]

Equipment

Equipment needed depends on the type of technique utilized. A proper injecting needle will be required for each block. During a regional block placement, patients should be oxygenated and monitored with pulse oximetry, electrocardiography, and blood pressure monitoring.[3] A regional cart containing emergency medications like lipid emulsion and ACLS medications should be available to treat regional blocks related complications.

For epidural procedures, a Tuohy needle and a loss of resistance syringe are required to locate the epidural space. Spinal needles have been refined over the years, with pencil-point needles having shown to reduce post-dural puncture headache incidence. There are numerous premade neuraxial kits available containing the required equipment.[3]

When performing a peripheral nerve block, the goal is to deposit the local anesthetic close to the nerve. The nerve may be located by anatomic landmarks in conjunction with one or more nerve identification techniques. A nerve stimulator is a portable device that delivers an adjustable electrical current to a needle's tip. An electrical pulse is transmitted to stimulate the nerve, and if the tip of the needle is close enough, a specific muscular group response can be evaluated.

Ultrasound guidance permits direct visualization of the needle location relative to the target nerve and other known structures. Portable ultrasound machines are available, with high and low-frequency probes, to identify both superficial and deep structures. Both devices can be used together to improve the success rate of the block, decrease the onset of the block, reduce the volume of local anesthetic required, and reduce the risk of vascular puncture.

Drugs used are local anesthetics and adjuvants, are chosen according to the onset and duration of action, degree of motor blockade, and toxicity. Local anesthetics with a shorter duration of action and quicker onset include lidocaine and mepivacaine, and the longer-acting ones are bupivacaine and ropivacaine. More than one can be combined to decrease onset time while providing a longer duration of analgesia.

Preparation

A complete checklist assessment should be performed before preparing the patients. Such checklists have shown to reduce medical errors, and may include patients name and date of birth, planned surgical procedure, completion of consents, patient allergies, coagulation status, and the surgical site marked by the surgeon. Before placing a block, the patient should be monitored with pulse oximetry, electrocardiography, and blood pressure monitoring, as described in the American Society of Anesthesiologists' standards for basic anesthetic monitoring.

An IV access should be secured to administer rescue medication in an emergency or sedation if needed, and supplemental oxygen therapy should be started.As an anesthetic procedure, the standard and emergency anesthesia equipment and medications should be prepared, including airway equipment. Aseptic skin preparation is needed as a strict aseptic technique must be used for all the blocks, including sterile gloves, masks, and surgical drapes.

Technique

Neuraxial Anesthesia (Spinal/Epidural/Combined)

Neuraxial blocks consist of placing a needle through the back to inject a specific drug into the subarachnoid space for spinal anesthesia or in epidural space for epidural anesthesia. Both techniques can be applied together.[4]

Epidural Anesthesia

Epidural anesthesia is administered by introducing a needle between the lumbar, thoracic, or cervical vertebrae and injecting the anesthetic agents into the epidural space, directly or through a catheter. The sitting and lateral decubitus positions are commonly used. The epidural needle can be inserted using a midline or a paramedian approach; the latter is used more frequently for thoracic insertions. Once a spinal level is chosen, the epidural needle is placed in the interspace between two spinous processes and advanced through skin, soft tissue, and spinal ligaments until the needle's tip enters the epidural space, the loss of resistance can be recognized. The anesthetic solution may be injected directly through the epidural needle into the epidural space, but more commonly, a catheter is inserted into space, and an anesthetic solution is administered. A transparent, occlusive, sterile dressing should be placed over the catheter insertion site, and the catheter should be marked and secured to the patient body.

Spinal Anesthesia

To perform a spinal block, a local anesthetic is injected into cerebrospinal fluid in the lumbar spine to numb nerves that exit the spinal cord. This is achieved by placing a needle between the lumbar vertebrae and through the dura to inject the medication. As the spinal cord usually ends between the first and second lumbar vertebral bodies, spinal anesthesia should be performed no higher than that level to avoid damage to the cord. Spinal anesthesia is administered as a single injection, whereas when performing an epidural block, a catheter is usually placed to use a continuous infusion or subsequent boluses.

The most frequent use is for surgeries involving the lower abdominal, pelvis, and lower extremities. 

Peripheral Nerve Blocks

Peripheral nerve blocks are particularly used for surgical procedures involving the upper or lower extremities and nonsurgical analgesia. Ultrasound guidance and nerve stimulator techniques are typically used to locate the anatomic structures and define the placement of the needle or catheter. Different techniques are described depending on the specific body area that needs to be numbed and if the local anesthetic is placed near a nerve or group of nerves, or spread between muscle planes. The commonly used blocks are:[5][6]

  • Upper extremity blocks (interscalene, suprascapular, infraclavicular, axillary, intercostobrachial, wrist, and digital nerve blocks.)

  • Lower extremity blocks (lumbar plexus (psoas compartment), femoral nerve block, fascia iliaca, obturator nerve, popliteal, saphenous, ankle, and digital nerve block.)

  • Scalp block

  • Cervical plexus block

  • Thoracic nerve blocks (intercostal, paravertebral, interfascial plane blocks)

  • Abdominal nerve blocks (transversus abdominis plane, subcostal, rectus, ilioinguinal and iliohypogastric, transversalis fascia plane, and quadratus lumborum block)

  • Pudendal and paracervical blocks

Please refer to the specific chapter for further information on peripheral nerve blocks.

Intravenous Regional Anesthesia 

Intravenous regional anesthesia or Bier block is a technique used for short procedures on the hand and forearm. It consists of replacing venous blood of the arm with local anesthetics. To perform a Bier block, an intravenous catheter is placed in the operative hand. Afterward, the arm is exsanguinated by lifting and allowing passive exsanguination, and then wrapping with an Esmarch bandage. A double pneumatic tourniquet is then placed and insufflated (first the distal, followed by the proximal one) 100 mmHg above the patient's systolic blood pressure. After checking the correct placement of the tourniquets, the Esmarch bandage can be removed once the distal cuff is released.

Typically a short-acting local anesthetic is given through the IV (usually 0.5% lidocaine or prilocaine if available), over 3 minutes, and waiting at least 30 minutes before the tourniquet is deflated to avoid the potential complication of local anesthetic toxicity. Intravenous regional anesthesia is not usually performed for lower limb surgery because larger amounts of local anesthetics would be required. Complications of this technique involve major local anesthetic toxicity (usually after deflation or tourniquet malfunction, where high systemic concentration may occur), dizziness, facial numbness, blurred vision, tinnitus, nerve damage, thrombophlebitis, and compartment syndrome. The benefit of the Bier block is that no special equipment is required, but in turn, no residual analgesia is provided; therefore, postoperative pain would need to be treated by systemic drugs or a surgical block.[7]

Complications

The safe practice of neuraxial anesthesia requires a profound knowledge of potential complications, incidence, and risk factors. Each technique is associated with specific complications. The main complications seen in regional anesthesia are block failure, neural injury, and local anesthetic toxicity. Permanent neurological injury in central neural blockades is rare, but transient injuries may occur more frequently (0.01 to 0.8%). Local anesthetics toxicity is rare (0.01%) and is more frequently associated with a regional nerve block. Although not frequent, allergic reactions to local anesthetics may occur.[8][9]

Postdural puncture headache is a common (<1%) complication related to epidural and spinal anesthesia. Backache is a frequent complaint of neuraxial anesthesia. The pain is usually mild and self-limiting, but it may last for several weeks.[10]

Central neural blockade may cause hypotension and severe bradycardia, most frequently seen with higher vertebral lever punctures. Epidural or spinal hematoma is rare but can cause irreversible damage if it is not diagnosed promptly. Epidural abscess is a serious but not frequent (0.07%) complication after neuraxial block.

Clinical Significance

Regional anesthesia has become one of the mainstays of perioperative pain management. It has significantly diminished postoperative pain in orthopedic and thoracic surgeries, reduced the use of general anesthesia in obstetrics, and provides significant reduction of perioperative pain, ultimately leading to improved patient outcomes.

Enhancing Healthcare Team Outcomes

There are risks and benefits to both neuraxial and general anesthesia. There are no clear advantages to one type of anesthesia over the other when either would be appropriate. Decisions about an anesthetic technique should be made based on different factors, including the patient, surgeon, type of procedure, and the anesthesiologists' preference. Specific protocols should be used to conduct regional anesthetic procedures to ensure patient safety and improve patient outcomes.

Nursing, Allied Health, and Interprofessional Team Interventions

Nurses should be trained in preparing the equipment and drugs required. Also, specific monitoring should be placed before a block is performed. Besides monitoring and registering the vital signs, the effects of the regional anesthesia should be evaluated, and the level of pain measured.

References

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Li J, Lam D, King H, Credaroli E, Harmon E, Vadivelu N. Novel Regional Anesthesia for Outpatient Surgery. Curr Pain Headache Rep. 2019 Aug 01;23(10):69. [PubMed: 31372836]

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Loizou E, Mayhew DJ, Martlew V, Murthy BVS. Implications of deranged activated partial thromboplastin time for anaesthesia and surgery. Anaesthesia. 2018 Dec;73(12):1557-1563. [PubMed: 30315725]

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Doo AR, Shin YS, Choi JW, Yoo S, Kang S, Son JS. Failed dural puncture during needle-through-needle combined spinal-epidural anesthesia: a case series. J Pain Res. 2019;12:1615-1619. [PMC free article: PMC6526918] [PubMed: 31190971]

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Ahuja P, Singh R, Jain A. Effect of intrathecal catheterisation on incidence of postdural puncture headache after accidental dural puncture in non-obstetric patients. J Anaesthesiol Clin Pharmacol. 2019 Jan-Mar;35(1):49-52. [PMC free article: PMC6495619] [PubMed: 31057240]

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FitzGerald S, Odor PM, Barron A, Pawa A. Breast surgery and regional anaesthesia. Best Pract Res Clin Anaesthesiol. 2019 Mar;33(1):95-110. [PubMed: 31272657]

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Delbos A, Philippe M, Clément C, Olivier R, Coppens S. Ultrasound-guided ankle block. History revisited. Best Pract Res Clin Anaesthesiol. 2019 Mar;33(1):79-93. [PubMed: 31272656]

7.

Löser B, Petzoldt M, Löser A, Bacon DR, Goerig M. Intravenous Regional Anesthesia: A Historical Overview and Clinical Review. J Anesth Hist. 2019 Jul;5(3):99-108. [PubMed: 31570204]

8.

Uyl N, de Jonge E, Uyl-de Groot C, van der Marel C, Duvekot J. Difficult epidural placement in obese and non-obese pregnant women: a systematic review and meta-analysis. Int J Obstet Anesth. 2019 Nov;40:52-61. [PubMed: 31235212]

9.

Moraca RJ, Sheldon DG, Thirlby RC. The role of epidural anesthesia and analgesia in surgical practice. Ann Surg. 2003 Nov;238(5):663-73. [PMC free article: PMC1356143] [PubMed: 14578727]

10.

Atanassoff PG, Lobato A, Aguilar JL. [Intravenous regional anesthesia with long-acting local anesthetics. An update]. Rev Esp Anestesiol Reanim. 2014 Feb;61(2):87-93. [PubMed: 24156887]

Sours: https://www.ncbi.nlm.nih.gov/books/NBK563238/
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[Neurologic complications of central neuraxial blocks]

Central neuraxial blocks, which are associated with a low incidence of complications, are safe. When complications do occur, however, the resulting morbidity and mortality is considerable. The reported incidence of complications in all series is under 4 per 10000 patients, but given the absence of formal registries and notification procedures, which have legal implications, the real rate of occurrence of these rare events is uncertain. We searched the literature through PubMed and the Cochrane Plus Library for a 5-year period, using the search terms epidural anesthesia AND safety, spinal anesthesia AND safety, complications AND epidural anesthesia, complications AND spinal anesthesia, neurologic complications AND epidural anesthesia, and neurologic complications AND spinal anesthesia. Neuraxial injury after a central blockade may be the result of anatomical and/or physiological lesions affecting the spinal cord, spinal nerves, nerve roots, or blood supply. The pathophysiology of neuraxial injury may be related to mechanical, ischemic, or neurotoxic damage or any combination. When a complication occurs, factors related to the technique will have interacted with pre-existing patient-related conditions. Various scientific societies have published guidelines for managing the complications of regional anesthesia. Recently published clinical practice guidelines recommend ultrasound imaging as a useful tool in performing a central neuraxial block.

Sours: https://pubmed.ncbi.nlm.nih.gov/22046866/
Dr. Swati Singh discusses 'CENTRAL NEURAXIAL BLOCKADE'

Neuraxial Blocks: Spinal and Epidural Anesthesia

Regional Nerve Blocks in Anesthesia and Pain Therapy pp 499-559 | Cite as

  • Herman Sehmbi
  • Ki Jinn ChinEmail author

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Abstract

Central neuraxial techniques are among the most reliable regional anesthesia techniques at the disposal of the anesthesiologist. Although they are relatively simple to perform, a thorough knowledge of underlying neuraxial anatomy and factors determining the spread and duration of anesthesia is critical to their success. Also, an understanding of the physiological effects and potential complications of these neuraxial techniques is paramount to ensure safe application of these methods.

Keywords

Local Anesthetic Spinal Anesthesia Epidural Space Motor Block Ligamentum Flavum 

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Department of AnesthesiaToronto Western HospitalTorontoCanada
Sours: https://link.springer.com/chapter/10.1007/978-3-319-05131-4_41

Blocks neuraxial

The skin. Phoebe jumped up and knocked over the chair. The liquid rose up the elbows. The clothes began to dissolve and melt. "This sticky substance eats away clothes, but not organics.

Neuraxial Spinal Anesthesia Ultrasound assisted - Regional anesthesia Crash course with Dr. Hadzic

At least tell your parents a word, - I opened a couple of naked photos on my phone, - these pictures. Will be on the phones of the whole city, - I showed her. I will not tell anyone.- Alina whispered with her lips alone, closing her eyes.

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I even finished my butt, I haven't finished like that for a hundred years, such a pleasure. By the way, Lera's name is Valeria. I will be 19 in a week, you will come to my birthday, - she held out her gentle hand to me. And so ceremoniously introduced herself - Valeria Pavlovna.

Alexander, - I answer, shaking my narrow palm and also ceremoniously bowing my head, as if we were not in a student toilet, but at a reception in.



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