Cranial subdural haematoma after spinal anaesthesia: perhaps not so rare complication

Abstract

Editor, We have read the interesting case reported by Katircioglu et al.1 recently published in the European Journal of Anaesthesiology, about a patient who developed a cranial subdural haematoma (CSH) after an otherwise uneventful spinal anaesthetic performed for an abdominal surgical procedure. Throughout the letter, the authors state the rare presentation of this complication after epidural or spinal punctures and that the real incidence of CSH is unknown. However, some years ago, Reynolds2 outlined the fact that any subdural haematoma reported in the literature had been categorized as unusual. The author quotes 31 references of subdural haematomas (both intracranial or spinal) until his editorial in 1993.2 In a simple PubMed search (terms searched ‘lumbar puncture’ AND ‘subdural haematoma’, no other restrictions), we have found 57 cases or short case series of intracranial or spinal subdural haematomas (or both) published since 1994. Twelve of these occurred after an epidural puncture and 36 after a spinal puncture. The neuraxial puncture attempt was diagnostic in 17 cases, anaesthetic in 26 cases or therapeutic in nine cases. Again, most of these events were described as rare and unusual by the authors. Importantly, from a clinical point of view, a great part were described as of chronic course, with a delayed diagnostic or misdiagnosed, and in some cases, the final outcome was catastrophic, including the death of the patient.1–4 Moreover, most of the cases presented symptoms of postdural puncture headache (PDPH) prolonged in time, nonpostural, that changed in quality, were refractory to usual therapies (mostly the conservative ones), were neglected, and progressively worsened. If a patient who has received a neuraxial procedure involving a puncture presents symptoms of PDPH (both typical and especially atypical) and clinical features as described above, those should prompt a diagnostic suspicion different from PDPH to explain his/her headache, as Katircioglu et al. in part suggest.1 If the patient is discharged from the hospital, he/she should be informed of these possibilities in order to prevent a delay in diagnosis.1,3 Perhaps a few days is the time required to complete the diagnostic procedures and proceed with the therapeutic ones. This time is important to have in mind because the excessive cerebrospinal fluid (CSF) leakage seems to be the main cause of the CNS hypotension and tearing of intracranial subdural veins, and consequently the CSH.1–4 So, the performance of an epidural blood patch could be therapeutic for the PDPH and prophylactic2,3 for the not so unusual CSH. Although it is difficult to carry out an epidemiologic study evaluating this entity due to the absence of both the numerator (number of CSH) and the denominator (total number of spinal and epidural punctures), the number of cases published of a probably underreported complication seems to indicate a more than rare incidence of CSH.