Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

A new method has been developed to measure end-tidal carbon dioxide partial pressure (PECO2) during high frequency jet ventilation (HFJV). A digital flow controller incorporated in a computerized high frequency jet ventilator was used to deliver either a single deep breath or a series of three deep breaths. On user request, HFJV was interrupted and the deep breaths delivered, after which HFJV was resumed. Using a mathematical model, we were able to predict accurately the pressures to which the lungs would be inflated during deep breaths. The effect of varying the deep breath pressure (Pdb) on the ratio of end-tidal PCO2 to arterial (PCO2 (PECO2:PaCO2) was studied in three dogs. In all the dogs, within an optimum Pdb range of 5-10 cm H2O, PECO2 during the first deep breath was found to be similar (+/- 0.2 kPa) to the PaCO2 immediately before the onset of deep breaths. Deep breaths delivered above or below the optimum Pdb range resulted in a decrease in the ratio PECO2:PaCO2. The frequency of jet ventilation (12-200 b.p.m.) before the onset of the deep breaths did not affect PECO2:PaCO2.

Type

Journal article

Journal

Br J Anaesth

Publication Date

1989

Volume

63

Pages

47S - 52S

Keywords

Anesthesia, Intravenous, Animals, Carbon Dioxide, Dogs, High-Frequency Jet Ventilation, Microcomputers, Partial Pressure, Pressure, Pulmonary Alveoli, Respiration, Tidal Volume