Grand mal convulsion following epidural blockade

Abstract

We report a case of a 26 year old primigravid patient who underwent an urgent lower segment caesarean section under epidural blockade and who developed a grand mal convulsion. The patient weighed 72.1 kg and was admitted following the spontaneous onset of labour at 41 weeks gestation. Medical history revealed mild asthma treated with salbutamol and no history of convulsions, epilepsy or preeclampsia during the pregnancy. Two hours after admission lumbar epidural blockade was instituted at the L2/3 interspace, with the loss of resistance technique to saline. The epidural space was identified at 3.5 cm and 5 cm of cannula inserted into the space. Following a test dose of 3 ml of 0.5% plain bupivacaine a main dose of 7 ml of 0.5% plain bupivacaine was inserted through the catheter. Pain relief was effective and over the next 6 hours and 15 minutes 40 ml of 0.1% plain bupivacaine was infused through the catheter, (total dose 90 mg). Fetal distress occurred at this time and a decision was made to deliver the patient by caesarean section under epidural blockade. This required extension of the blockade. A test dose of 3 ml of 0.5% plain bupivacaine followed by a total of 11 ml of 0.5% plain bupivacaine over 20 minutes provided effective pain relief and extension of the block to T6. The operation proceeded and 10 minutes after the delivery of a live infant (15 minutes after the last injection of bupivacaine), without any warning or symptoms there was a sudden grand mal convulsion. Airway patency could not be maintained, therefore general anaesthesia was induced immediately. Following intubation anaesthesia was maintained with nitrous oxide 50%, oxygen 50% and halothane 0.4 to 0.5%. One hour and twenty minutes after the induction of