Anesthesiologists' ability in calculating weight-based concentrations for pediatric drug infusions: an observational study

Abstract

Study ObjectivesTo assess the ability of anesthesiologists to calculate weight-specific drug concentrations for continuous drug administration in children, and to evaluate the acceptance of an inhouse-developed, computer-based application for calculating drug infusions for pediatric cardiac surgery. DesignObservational study. SettingAnesthesiology department of a tertiary-care medical center in Israel. Participants45 anesthesiology department staff members (attendings and residents). MeasurementsAnesthesiologists were asked to calculate the weight-based amount of drug and the corresponding amount in mL to be drawn from a standard vial and added to a 50-mL syringe in order to reach an infusion rate, where 1 mL/hr corresponds to 1 μg x kg-1 x min-1. The time it took to reach the result was measured. Staff members were also asked to rate the user-friendliness and usability of the program. Main Results41 of the original 42 participants returned the completed questionnaire. Only 6 (15%) of 41 anesthesiologists provided all the correct answers. The mean calculation time required was 205 (±53) seconds. There was no difference in success rate between attendings and residents. Incorrect calculations ranged from a drug concentration 50 times too low up to 56 times too high. Most staff members believed that the computer-based application to perform these calculations reduced errors (65%) and workload (81%), and improved patient treatment (71%). This application was rated as very user-friendly. ConclusionsAnesthesiologists have difficulty calculating pediatric drug concentrations for continuous drug infusions. The correct calculations are time-consuming. Incorrect calculations may lead to dangerously high or low doses. A computer-based application to calculate drug concentrations was rated as very useful and user-friendly.