What is the cardiac index (CI) needed to maintain oxygen demand at a cooling temperature of 30 degrees?

The cardiac index (CI) is a crucial hemodynamic parameter that relates cardiac output to body surface area, allowing for the assessment of the heart's ability to meet the metabolic demands of the body. At a cooling temperature of approximately 30 degrees Celsius, the body experiences decreased metabolic rate and oxygen demand due to the physiological effects of hypothermia.

At this temperature, maintaining an adequate CI becomes essential, yet it can be achieved at lower values compared to normothermic conditions. A CI of 2.0 is considered sufficient for metabolic needs during mild hypothermia, allowing adequate oxygen delivery while recognizing the reduced need resultant from lower core temperature.

Higher values, such as 2.2 CI, may reflect a more typical requirement at normal body temperatures, while lower indices, such as 1.8 or 1.5 CI, could potentially lead to insufficient perfusion and oxygenation under normothermia due to the increased demand. Hence, the established value of 2.0 CI at 30 degrees serves as an adequate threshold to support tissue oxygenation while factoring in the altered metabolism associated with hypothermia.