What does the cardiac power output (CPO) formula calculate?

The cardiac power output (CPO) formula is designed to calculate the energy available to maintain organ perfusion. This value is crucial in the management of patients undergoing ECMO, as it provides insights into the heart's ability to deliver sufficient blood flow to meet the metabolic demands of vital organs.

CPO takes into account both cardiac output and systemic vascular resistance, allowing clinicians to assess the effectiveness of cardiac function relative to the whole body's needs. It provides an understanding of how well the heart can perform work over time in delivering oxygenated blood, which is essential for maintaining perfusion to organs like the brain and kidneys.

In contrast, other choices represent different concepts: the volume of blood pumped per heartbeat pertains to stroke volume, which is only one part of the broader cardiac output. The pressure gradient across the heart is a concept related to hemodynamics but does not directly correlate with calculating the energy available for perfusion. Lastly, heart rate multiplied by stroke volume indeed calculates cardiac output but does not factor in the energy conversion aspect that CPO addresses. The focus of CPO on energy availability makes it a critical measure in evaluating cardiovascular health, particularly in ECMO patients.