Critical Tools: Monitoring Oxygenation and Perfusion

a crucial goal in the critical patient is the maintenance of cellular health. Cellular health relies on adequate tissue oxygen delivery (Do2) to support aerobic metabolism. Do2 depends on the arterial oxygen content of blood and on tissue perfusion. Monitoring of these components, therefore, provides the clinician with a means to assess their status, and thus guide appropriate management. unfortunately, clinically available tools enable assessment of only aspects of this dynamic relationship. it is important, therefore, that such tools are used carefully, with their limitations in mind, and in the light of other findings.

This presentation will briefly review the physiology of tissue oxygen delivery and hypoxia, and discuss practical clinical tools of monitoring, including pulse oximetry, capnography, blood gas analysis, blood pressure measurement, and central venous pressure monitoring. Each will be addressed with respect to how and when to use them, practical tips, what they mean (and don’t mean) and how to put all this information together to benefit the patient.