A randomised trial comparing 5 mL/kg and 10 mL/kg of pentastarch as a volume preload before spinal anaesthesia for elective caesarean section

BackgroundColloid solutions are more effective at preventing hypotension than crystalloids when used as a volume preload before caesarean delivery under spinal anaesthesia. The ideal volume to infuse has not been established.MethodIn a randomised double-blind trial 70 women presenting for elective caesarean section received either 5 mL/kg of pentastarch (group A) or 10 mL/kg of pentastarch (group B) as a volume preload before spinal anaesthesia. Hypotension was defined as a systolic pressure below 90 mmHg or a decrease of 30% from a baseline value. Treatment was with 6-mg increments of ephedrine until resolution.ResultsIn group B, 7/35 patients (20%) developed hypotension, significantly fewer than the 15/35 (42.8%) in group A (P < 0.05). The patients in group B also required less ephedrine (total in group, 114 mg) than those in group A (total in group, 198 mg)ConclusionsPentastarch, 10 mL/kg is more effective than 5 mL/kg at preventing hypotension following spinal anaesthesia for caesarean delivery.