During Total intravenous anesthesia (TIVA), the anesthetic propofol and the opioid remifentanil are often used together. Previous studies have demonstrated the synergy between these combinations of medications. From these data, drug interaction models have been developed to pair drug effect-site concentrations with event markers of interest to the clinical anesthesiologist. For example, the amount of remifentanil and propofol typically required during the induction of anesthesia to cause loss of responsiveness to verbal or moderate stimuli has been studied. Likewise, the blood concentration levels present during emergence from anesthesia have been explored describing levels typically present for patients to return to consciousness.
The purpose of this study is to retrospectively analyze the infusion doses of both remifentanil and propofol for pediatric patients undergoing spinal fusion surgery at CHOP. These data will be applied to the pharmacokinetic models to determine the predicted effect site concentration, and the relationship of that concentration to the 50% and 95% doses as predicted by the model.
