While the topic remains up for debate as to exactly how much fluid these patients should have, there is supportive evidence to allow for a moderate intake for chronic heart failure patients, since the fluid overload is not within the systemic circulation.

Studies have shown that even one incidence of a systolic pressure less than 90 can double the mortality rate in a head injured patient with increasing intra-cranial pressure. While watching the systolic pressure is acceptable, MAP is a more informed way to maintain adequate Cerebral Perfusion Pressure (CPP).