EVALUATION OF AN OPEN-LOOP, COMPUTER-BASED INFUSION SYSTEM DESIGNED TO ACHIEVE A SERIES OF CONSTANT, TARGETED PLASMA PROCAINAMIDE CONCENTRATIONS IN PATIENTS UNDERGOING ELECTROPHYSIOLOGIC TESTING

Study Objective. To evaluate the performance of a computer-based proca inamide infusion system in patients undergoing electrophysiologic test ing. Design. Prospective case series. Setting. Electrophysiology labor atory in a university hospital. Patients. Thirty-four patients with in ducible sustained ventricular tachycardia. Interventions. Intravenous infusion of procainamide to achieve and maintain targeted plasma conce ntrations. Measurements and Main Results. System performance was asses sed by comparing targeted and observed plasma concentrations. The popu lation median absolute performance error (size of typical miss) was 12 .6% (95% CI 11.2-14.1%). The population median performance error (syst em bias) was not significantly different from zero. A small but statis tically significant improvement in performance over time was observed (population absolute performance error divergence -0.125%/min). Popula tion wobble (overall system stability) was 7.6% (95% CI 6.8-8.3%). Pop ulation-based estimates of central compartment volume and volume of di stribution at steady state were significantly higher and lower, respec tively, than estimates used by the infusion system. Conclusion. The co mputer-based infusion system is capable of achieving and maintaining a series of targeted procainamide concentrations in patients undergoing electrophysiologic testing.