Simulation analysis of the performance of target-controlled infusion of propofol in Chinese patients

Background: The performance of target-controlled infusion (TCI) devices is important for the safety of patients. This study examined the performance of two propofol pharmacokinetic parameter sets in Chinese patients by computer simulation. Methods: Two sets of propofol pharmacokinetic parameters respectively derived from Marsh's and Schnider's studies were compared with those obtained in Chinese subjects from Li's study. Pharmacokinetic parameters of propofol from Li's study for subjects of three different entities (average adult, obese adult, and elderly) were used to estimate the performance of Marsh's and Schnider's models. Sixty virtual patients were generated with Li's parameters. A computer program, STANPUMP, was used to perform the pharmacokinetic simulation. An induction dose of propofol at 2 mg/kg for average or obese adult, while 1.5 mg/kg for the elderly, followed by TCI of 4 μg/mL (average and obese adult) or 3 μg/ mL (elderly) were simulated. The infusion schemes generated by STANPUMP using Marsh's or Schnider's model were put in to simulate the predicted plasma concentration based on the pharmacokinetic parameters from Li's study. The median performance error (MDPE) and absolute median performance error (MDAPE) were calculated to estimate the bias and inaccuracy. Differences between models were calculated using the paired t test. A P value < 0.05 was considered statistically significant. Results: The bias and inaccuracy by Marsh's model in average adults were -11.9% and 18.5% respectively and by Schnider's model were -8.6% and 17.9%. For obese adults, the bias and inaccuracy were 6.3% and 26.2% respectively for Marsh's model and -6.6% and 22.6% for Schnider's model. Schnider's model resulted in a significantly greater inaccuracy than Marsh's model (42.1% versus 15.5%) when applied to elderly patients. Conclusions: The performance of TCI infusion of propofol in Chinese patients is generally acceptable with Marsh's or Schnider's model apart from using Schnider's model in Chinese elderly patients. Further study to investigate the difference of propofol pharmacokinetics between Chinese and non-Chinese elderly patients is necessary.