We report that the pediatric cardiogenic shock and septic shock populations show similar hemodynamic and oxygen utilization physiologic relationships during aggressive intensive care therapy. We examined the mathematical relationships between vascular tone and flow, and oxygen utilization and oxygen delivery (DO2) in the early and middle stages of cardiogenic and septic shock. The fitted curves between cardiac index and systemic vascular resistance, and oxygen consumption (VO2) and DO2 were clinically and statistically similar in both shock populations. We found no evidence for decreased oxygen extraction in sepsis as compared to the cardiogenic shock population. In addition, it appears that the major determinant of VO2 in these populations is DO2, not oxygen extraction. We suggest that patients with cardiogenic or septic shock can be treated according to similar physiologic principles.