General anaesthesia using remifentanil for caesarean section in parturients with critical aortic stenosis: a series of four cases.

Although heart disease is now the joint leading cause of maternal mortality in the UK, critical aortic stenosis is rarely encountered in parturients. Caesarean section is advisable in these patients to minimise the haemodynamic stress of labour and delivery. The use of an opioid-based general anaesthetic technique also helps to maintain cardiovascular stability. During a two-year period, four women with critical aortic stenosis requiring caesarean section presented to our institution. In all women, a rapid sequence induction of anaesthesia was performed using etomidate 0.1 to 0.2 mg.kg(-1), suxamethonium 1.5 mg.kg(-1) and remifentanil 2 to 4 micrograms.kg(-1). Anaesthesia was then maintained with isoflurane, nitrous oxide and a remifentanil infusion at 0.05 to 0.15 micrograms.kg(-1)min(-1). There was good haemodynamic stability throughout, except for a short period in one patient who became hypotensive after a significant post-partum haemorrhage secondary to uterine atony. All parturients were successfully extubated at the end of surgery and made excellent postoperative recoveries. Neonates were born in good condition with Apgar scores of 10, 9, 6 and 5 at 1 min and 10, 10, 10 and 10 at 5 min. We suggest that remifentanil is an ideal agent for parturients with severe aortic stenosis requiring general anaesthesia for caesarean section. Remifentanil provides cardiovascular stability in conjunction with rapid emergence from anaesthesia in the parturient and minimal side effects in the neonate.