[Total intravenous anesthesia with Diprivan (1% propofol emulsion) using a manual drip-infusion technique]

Continuous intravenous administration of Diprivan (1% propofol emulsion, P) is usually carried out using a syringe-pump or an infusion-pump to adjust the infusion rate. We assessed the accuracy of the infusion dose of P and the serum concentration of propofol by manual controls during anesthesia. Twenty eight patients, anesthetized with oxygen, P and vecuronium in combination with fentanyl and epidural block were randomly assigned to either of the following groups; P was administered using the drip-infusion (the group D, n = 14) or a syringe-pump (the group S; n = 14). In the group D, we used the drip-rate table to calculate the dose of P. We assessed (1) the total infusion volume of P which was calculated from the infusion rate and duration (Vc), and also measured by a calibrated cylinder (Vm) in the group D (n = 14) and group S (n = 14), and (2) the serum propofol concentrations 40 min after infusion of P (6 mg.kg-1.hr-1) were assayed using the HPLC. The Vc was well correlated with the Vm in the group D (r = 0.976) and in the group S (r = 0.974). Mean serum propofol concentrations of the group D and S were 2.50 +/- 0.57 and 2.35 +/- 0.62 micrograms.ml-1, respectively. The results suggest that the drip-infusion technique of P may be substituted safely by the syringe-pump for continuous total intravenous anesthesia.