RESUMO
This study presents an artificial neural network-based controller for regulating the level of induced paralysis during surgery using vecuronium bromide. The controller uses the myogram of a rapid muscle contractions (called twitch) to generate the appropriate infusion rate. The controller is self-adjusting and can accommodate inter- and intrapatient drug response variations. It also withstands changes in the pure time delay and nonlinear pharmacokinetic parameters of the response. Another feature of the controller is that it does not depend on a priori knowledge of the patient response model. Computer simulations using pharmacokinetic and pharmacodynamic models showed negligible steady-state error and maximum percent undershoot averaged to 6.24%. The average infusion rate for 90% paralysis was 1.22 (microg x kg(-1) x min[-1]).
