Predictive Value of Core — Toe Temperature and Mixed Venous Oxygen Saturation After Cardiac Surgery

Abstract

Some of the patients returning to the surgical intensive care unit resemble a shock like condition. They are pale, cold, have a clammy skin and a low mixed venous oxygen saturation. All their signs point to hypovolemia and require intravenous fluidloading. The hypothesis that a-blockade is useful in such patients was tested in a randomly selected group of patients. Group 1, 43 patients with severe cardiac deformities, received a-blockade (largactil 2.5 to 5 mg i. v.) while group II, 25 patients undergoing similar cardiac surgery did not receive any a-blockade drug. Fluid replacement was similar in both groups.

The relationship between a hypovolemic state and the presence of a gradient between the central and the peripheral temperature in the body is well recognized. It was found that narrowing of temperature gradient occurred in the same time interval in both groups after arrival at the SICU. The temperature gradient (skin-core) was 12°C immediately on arrival at SICU. With fluid replacement at 128 ml/hour the gradient narrowed within less then 6 hours in both groups. With narrowing of the temperature gradient there was a concomitant rise of mixed venous oxygen saturation.

It is concluded that the use of α-blockade drugs in the treatment of hypovolemic shock is unnecessary, provided adequate volume replacement under guidance of the core-skin temperature gradient is carried out.