Epidural hematoma secondary to removal of an epidural catheter after a total knee replacement. A case report

Neuraxial blocks and spinal haematoma: Review of 166 cases published 1994 – 2015. Part 2: diagnosis, treatment, and outcome

Background

Bleeding into the vertebral canal causing a spinal haematoma (SH) is a rare but serious complication to central neuraxial blocks (CNB). Of all serious complications to CNBs, neurological injury associated with SH has the worst prognosis. Around the turn of the millennium, the first guidelines aiming to reduce the risk of this complication were published. These guidelines are based on known risk factors for SH, rather than evidence from randomized, controlled trials (RCTs). RCTs, and hence meta-analysis of RCTs, are not appropriate for identifying rare events. Analysing data from a significant number of published case reports of rare complications may reveal risk factors and patterns undetectable in reports on occasional cases, and can thereby help to improve management of CNBs. The aims of the present review were to analyse case reports of SH after CNBs published between 1994 and 2015 with regard to diagnosis, treatment, and outcome of SH after CNB.

Methods

MEDLINE and EMBASE were utilized to find case reports published in English, German, or Scandinavian languages between 1994 and end of 2015, using appropriate search terms. Reference lists were also scrutinized for case reports. We documented initial and worst symptoms and signs of SH, diagnostic methods, treatment, and outcome of the SH. We calculated occurrences in per cent using the number of informative reports as denominator.

Results

One hundred and sixty-six case reports on spinal hematomas after CNB published during the years between 1994 and 2015 were identified. Eighty per cent of the patients had severe neurological symptoms (paresis or paralysis). When compared over time, outcomes have improved significantly. Among patients subjected to surgical evacuation of the hematoma, outcomes were best if surgery was performed within 12 hours from the firstsign of motor dysfunction. However, even patients operated after more than 24 hours had relatively favourable outcomes. Whereas the outcomes after surgical evacuation of the epidural haematomas were quite satisfactory, only one of the operations for subdural haematoma (SSDH) resulted in a favourable outcome.

Conclusions and implications

Suspicion of a spinal hematoma calls for the consultation of an orthopaedic or neurological surgeon without delay. MRI is the recommended diagnostic tool. Surgical evacuation within 12 h from the first sign of motor dysfunction seems to lead to the best outcome, although many patients operated as late as after more than 24 hours did regain full motor function. Despite the poor prognosis after surgical evacuation of SSDH, the outcomes after post-CNB spinal haematoma in general have improved significantly over time.

Neuraxial blocks and spinal haematoma: Review of 166 case reports published 1994–2015. Part 1: Demographics and risk-factors

Background

Bleeding into the vertebral canal causing a spinal haematoma (SH) is a rare but serious complication to central neuraxial blocks (CNB). Of all serious complications to CNBs such as meningitis, abscess, cardiovascular collapse, and nerve injury, neurological injury associated with SH has the worst prognosis for permanent harm. Around the turn of the millennium, the first guidelines were published that aimed to reduce the risk of this complication. These guidelines are based on known risk factors for SH, rather than evidence from randomised, controlled trials (RCTs). RCTs, and therefore meta-analysis of RCTs, are not appropriate for identifying rare events. Analysing published case reports of rare complications may at least reveal risk factors and can thereby improve management of CNBs. The aims of the present review were to analyse case reports of SH after CNBs published between 1994 and 2015, and compare these with previous reviews of case reports.

Methods

MEDLINE and EMBASE were used for identifying case reports published in English, German, or Scandinavian languages, using appropriate search terms. Reference lists were also scrutinised for case reports. Twenty different variables from each case were specifically searched for and filled out on an Excel spreadsheet, and incidences were calculated using the number of informative reports as denominator for each variable.

Results

Altogether 166 case reports on spinal haematoma after CNB published during the years between 1994 and 2015 were collected. The annual number of case reports published during this period almost trebled compared with the two preceding decades. This trend continued even after the first guidelines on safe practice of CNBs appeared around year 2000, although more cases complied with such guidelines during the second half of the observation period (2005–2015) than during the first half. Three types of risk factors dominated:(1)Patient-related risk factors such as haemostatic and spinal disorders, (2) CNB-procedure-related risks such as complicated block, (3) Drug-related risks, i.e. medication with antihaemostatic drugs.

Conclusions and implications

The annual number of published cases of spinal haematoma after central neuraxial blocks increased during the last two decades (1994–2015) compared to previous decades. Case reports on elderly women account for this increase.Antihaemostatic drugs, heparins in particular, are still major risk factors for developing post-CNB spinal bleedings. Other risk factors are haemostatic and spinal disorders and complicated blocks, especially “bloody taps”, whereas multiple attempts do not seem to increase the risk of bleeding. In a large number of cases, no risk factor was reported. Guidelines issued around the turn of the century do not seem to have affected the number of published reports. In most cases, guidelines were followed, especially during the second half of the study period. Thus, although guidelines reduce the risk of a post-CNB spinal haematoma, and should be strictly adhered to in every single case, they are no guarantee against such bleedings to occur.

Late spinal subdural haematoma after spinal anaesthesia for total hip replacement

We present a case of delayed presentation of a subdural haematoma causing cauda equina syndrome which occurred 96 hours after a spinal anaesthetic had been administered for an elective total hip replacement in an 86-year-old man. The patient had received low-molecular-weight heparin anticoagulation which had been delayed until 12 hours postoperatively. No other cause of the haemorrhage could be identified.