Oxygen transport in cardiogenic and septic shock

Abstract

Objective: To review clinical studies of oxygen transport in cardiogenic and septic shock.

Design: Descriptive and prospective studies.

Setting: University hospital multi disciplinary ICU.

Patients: Critically ill cardiogenic and septic shock patients greater than 18 and less than 80 yrs of age.

Interventions: The responses to volume loading with colloid or crystalloid and infusion of catecholamines are documented with baseline hemodynamic and oxygen transport measurements before and after administration of catecholamines.

Measurements and main results: Nineteen patients in cardiogenic shock were studied. In three patients, invasive systemic mean arterial pressure was greater than 80 mm Hg and cardiac index was greater than 2.0 L/min.m2. In all patients, there were increases in oxygen extraction ratio that averaged 48 +/- 18 (SD) %. However, in 30 septic shock patients, extraction ratio was 24 +/- 2%. In both groups, the response to therapy was an increase in mixed venous oxygen saturation from 54 +/- 16% to 69 +/- 8% in cardiogenic patients (p less than .001) and from 75 +/- 2% to 80 +/- 1% in septic shock (p less than .01).

Conclusions: There are widely differing oxygen transport patterns in cardiogenic and septic shock that may have implications for therapy.