Background: Since May 2011, the company that produced sodium thiopental in France stopped its marketing, mainly because of economic challenges. However, many physicians experienced in obstetric anaesthesia still use this drug for general anaesthesia during caesarean section (CS) for historical reasons, pharmacological properties, license concerns or effects on the newborn child. Because of limited comparative evidences, induction agent choice remains a controversial subject, especially in case of emergency where datas are lacking. The objectives of this study, were to compare the effects of propofol versus thiopental on the neonate outcome in context of elective and emergency CS. 

Method: From 2009 January to 2013 December neonates delivered from ASA I and II pregnant women by elective or emergency cesarean section under general anesthesia, in a French teaching hospital, were included. Two periods, according to the hypnotic drug was compared: before may 2011 (induction with thiopental) and after (induction with propofol). The primary outcome was the Apgar score at 1, 5 and 10 minutes, the secondary outcomes were the arterial umbilical pH and the admission rate in a neonatal care unit. Results are expressed in median. A chi2 was performed for comparisons. A p < 0.05 was significant.

Results: 367 newborns were included, n=178 in thiopental (6.2 ± 1.8 mg/kg) and n=189 in propofol (3.5 ± 0,9 mg/kg) periods. Demographic characteristics of parturients were similar in both periods. The Apgar score was higher during thiopental than propofol period with 7 (2-9) vs 5 (2-8) (p=0.01) at 1 minute; 9 (6-10) vs 7 (6-9) (p=0.002) at 5 minutes but similar at 10 minutes. For emergency CS with extraction time < 10 min or 10-60 minutes, Apgar score was higher during thiopental period, but only at 1 minutes, 8 (4-9) vs 6 (3-9) (p=0.016), and when extraction time was 10-60 min. Blood gases analyses and admission rate of neonates in care unit were similar between the two periods whatever the timing of CS.

Conclusion: The place of the thiopental instead of propofol for CS under general anesthesia has to be prospectively assessed. Because we did not find any difference at 5 minutes for CS in emergency, the deleterious effect of propofol for the neonate is probably low.

General anaesthesia for cesarean section: Is thiopental missing?