Blood Gas Analysis
摘要
The blood gas is one of the most accurate measures of oxygenation and ventilatory status in the mechanically ventilated patient. The blood gas provides information on the patient’s acid/base status, allowing clinicians to determine if the patient has an acidemia or alkalemia, and many processes can be determined as well. Arterial blood gases also provide information on oxygenation, but the pO2 on a peripheral venous blood gas cannot be used clinically. The blood gas may also offer electrolytes on point-of-care testing, thereby providing a metabolic picture of the body, occasionally unveiling otherwise insidious pathology. Although this chapter focuses on blood gas, we’ll also discuss alternative methods of assessing metabolic status when a blood gas is unavailable and the implications of those results on ventilator management.