We read with interest the case report of Mashour et al. ,1who reported a bilateral subdural hematoma (SDH) in a parturient after epidural anesthesia. In a previous report,2we reviewed 47 cases of cerebral hemorrhage after spinal (26 cases) and/or epidural (21 cases) anesthesia (table 1). Almost half of the patients developed bilateral subdural hematoma after dural puncture by an epidural needle. In contrast, subdural hematoma after spinal anesthesia occurred most frequently on the left side of the brain. It is possible that the increased incidence of bilateral subdural hematoma after epidural (11 of 21) versus  spinal anesthesia (4 of 26) can be attributed to the greater loss of cerebrospinal fluid volume after inadvertent dural puncture with a large-bore epidural needle. Cerebrospinal fluid leak through a large dural hole might lead to marked cerebral hypotension associated with excessive traction on the bridging veins on both sides of the brain, resulting in bilateral subdural hematoma formation.

Table 1. Cerebral Subdural Hematoma after Spinal  versus Epidural Anesthesia 

Table 1. Cerebral Subdural Hematoma after Spinal  versus Epidural Anesthesia 
Table 1. Cerebral Subdural Hematoma after Spinal  versus Epidural Anesthesia 

Further analysis of the 47 cases of SDH showed that half of the published cases were in obstetric patients (22 of 47 cases); 6 cases were reported after spinal anesthesia, and 17 cases followed epidural anesthesia. It is possible that pregnant patients are more liable to develop post–dural puncture subdural hematoma. However, this observation might be attributed, in part, to the frequent use of epidural analgesia during labor.

We agree with Mashour et al.  1that SDH has been found to develop after inadvertent dural puncture even when an epidural blood patch was placed. Analysis of the published cases of SDH (table 1) showed that epidural blood patch was used in 8 of 21 cases to treat post–dural puncture headache, but this treatment did not prevent the formation of SDH. However, SDH was not ruled out before applying the blood patch.

*Sahel General Hospital, Beirut, Lebanon. doczeidan@hotmail.com

1.
Mashour GA, Schwamm LH, Leffert L: Intracranial subdural hematomas and cerebral herniation after labor epidural with no evidence of dural puncture. Anesthesiology 2006; 104:610–2
2.
Zeidan A, Farhat O, Maaliki H, Baraka A: Does postdural puncture headache left untreated lead to subdural hematoma? Case report and review of the literature. Int J Obstet Anesth 2006; 15:50–8