High frequency ventilation (HFV) is a new ventilatory technique that uses very small tidal volume (less than the anatomic dead space) and high frequency, and classified 4 distinct types according to frequency and mode of gas delivery. The mechanism of gas transport of high frequency oscillation ventilation (HFOV) is somewhat different to other types of HFV. To evaluate the determinants of PaCO² in HFOV, a study was done with a HFOV on 9 cats, and the results are: 1) PaCO² was not correlated with frequency at the constant stroke volume (6 voltage) and bias flow (6 L/minutes). 2)PaCO² was correlated with stroke volume but not with bias flow under the constant frequency (15 Hz/min) and bias flow (3 to 6 L/min). From above results, the main determinant of PaCO² on artificial ventilation with HFOV was stroke volume, but further study between flow, the site of delivery to the airway and humidification of bias flow and CO² elimination is required in future research.
Animals ; Bias (Epidemiology) ; Cats* ; High-Frequency Ventilation* ; Stroke Volume ; Tidal Volume ; Ventilation