pulmonary ventilation rate and dead space

VT, VD and PIP were lower in hITPV than in VCV under I : E ratios of 1 : 2 and 1 : 1 at the same RR. Mean values of PaO2 were higher than 400 mmHg during the experiment. RESULTS PaCO2, VCO2 and alveolar ventilation were statistically constant with various RR with the same I : E ratio during VCV and hITPV. Blood pressure and airway pressures were monitored and the dead space ratio was calculated. We aimed at maintaining normal partial pressure of arterial CO2 (PaCO2) and minute CO2 clearance (VCO2) while the respiratory rate (RR) was set at 20, 40, 80 or 120/min with an inspiratory to expiratory (I : E) ratio of 1 : 2 or 1 : 1. METHODS VCV and hITPV were compared in 6 tracheostomized rabbits.

We hypothesized that hITPV might reduce the dead space/tidal volume ratio as compared with volume controlled ventilation (VCV).

Hybrid ITPV (hITPV) is a continuous flow ventilatory technique that adopts inspiratory fresh gas from a ventilator and RTC. Gas is intermittently re-directed into the lung as a tidal volume by a valve on the expiratory circuit. After exiting from the catheter tip in the distal trachea, the flow of gas is directed outward away from the lungs. BACKGROUND: Intratracheal pulmonary ventilation (ITPV) is a form of tracheal gas insufflation which enhances the clearance of CO2 from dead space and lungs by a bias gas through a reverse thrust catheter (RTC).

Pulmonary ventilation rate and dead space