An on-line hybrid computing system for dynamic respiratory response studies

Abstract

This paper describes a hybrid computing system for on-line human respiratory studies. A digital computer dictates the subject's inspired CO 2 concentration through a servocontrolled breathing chamber. The inspired CO 2 is varied so that the alveolar CO 2 concentration has a useful dynamic perturbation. A special purpose analog computer system measures and displays respiratory response data in real time and an on-line digital system accumulates these data on a breath-to-breath basis. A digitally controlled breath sound simulator is used to study the subject's voluntary interaction with his involuntary CO 2 response. Examples of experimental data are presented. The system is presently in use in ongoing studies of the normal and drug-altered respiratory control system.