In the equation CO = ECMO flow x (s1-s2)/(s3-s2), what does "CO" stand for?

In the context of the equation provided, "CO" stands for cardiac output. Cardiac output is a crucial physiological parameter that measures the amount of blood the heart pumps in one minute.

When utilizing ECMO, understanding cardiac output is vital as it reflects the perfusion capacity and effectiveness of the mechanical support being provided by the ECMO system. The equation itself is demonstrating how the flow from the ECMO machine correlates with the difference in various parameters (s1, s2, s3) that may represent pressure or other related measures in the ECMO circuit. It illustrates that the amount of blood being delivered by the ECMO system directly influences the cardiac output, reinforcing its role in maintaining adequate circulation and oxygen delivery to tissues.

While the other options seem plausible, they do not accurately represent the established terminology used in critical care and ECMO. Cumulative output, circulatory output, and consistent output are not standard terms associated with the measurement of the heart's function in this context, reinforcing the significance of cardiac output as the correct interpretation of "CO."