SIMULATION AND COMPARATIVE STUDIES OF DEAD SPACE LOADING FOR HUMAN RESPIRATORY CONTROL UNDER EXERCISE AND CO_2 INHALATION

摘要

In this paper, the effect of imposed external dead space on ventilator responses of respiratory control is simulated. Comparative studies are presented with respect to two dead space models under eucapnia and hypercapnia. A human respiratory control simulator based on the optimal chemical-mechanical respiratory control model is implemented with Lab VIEW environment and employed for current study. Simulations of respiratory control with and without external dead space loading are performed under rest, muscular exercise with CO_2 output of 0.2-1.0 (L/min), and CO_2 inhalation of 2-7%. Various ventilatory responses, including arterial partial pressure of CO_2, breathing frequency, tidal volume, total ventilation, alveolar ventilation, under different levels of dead space loading are derived and examined based on the optimized neural muscular drive, airflow, and lung volume profiles with minimum effort of breathing.