Development of a Continuous Blood p02Measuring System.

摘要

Three prototype blood partial pressure of oxygen monitors were fabricated and tested. The prototype systems utilize a null balance technique to obtain accurate in-dwelling blood gas measurements that are independent of the effects of blood on the disposable catheter. The null system balances the composition of a reference gas with that of the blood,across a catheter-tip membrane. The reference gas partial pressure of oxygen is then measured and is equivalent to that of the blood. In-vitro tests have shown that background gases do not affect the partial pressure of oxygen reading,which is accurate to within about +1mmHg. In-vivo testing of the Null System has shown good agreement with in-vitro blood sample analysis. Transient response to single-breath oxygen inspiration was similar to that of a commercial Clark electrode. A test of the Severinghaus sensor in the recirculating reference gas loop has shown the feasibility of C02measurement by this technique.