IN the past decade determinations of blood gas tensions and pH, when used as an adjunct to other physiological and biochemical monitoring, has markedly reduced the mortality associated with major cardiovascular operations. Alterations in blood gas tension and pH often precede changes in arterial and venous pressure, electrocardiogram, electroencephalogram, or clinical appearance of the patient. Appropriate treatment can be instituted before cardiac asystole or ventricular fibrillation ensues. The following is an experience with routine monitoring of gas tensions and pH in patients undergoing major operative procedures.
Materials and Methods
The pH, Pco2 and PO2 determinations were made on heparinized central venous and/or arterial blood samples prior to induction of anesthesia and at 20- to 30-minute intervals during operation in 100 consecutive and unselected patients. There were 70 elective and 30 emergency operations, and the ratio of males to females was 3:1. The ages ranged between 6 and 85