Rapid saline infusion (15 ml/kg) during passive heating restored central venous pressure and significantly increased cutaneous vascular conductance (P<0.05), unlike in normothermic controls.
p-value: p=<0.05
Whole body heating in humans increases skin blood flow (SkBF) and decreases central venous pressure (CVP). This study sought to identify whether elevations in SkBF are augmented during passive heating if CVP is increased during the heat stress. Seven subjects were exposed to passive heating. Once SkBF was substantially elevated, 15 ml/kg warm saline were rapidly infused intravenously. Whole body heating significantly increased cutaneous vascular conductance and decreased CVP from 7.7 +/- 0.6 to 4.9 +/- 0.5 mmHg (P 0.05) and significantly increased cutaneous vascular conductance relative to the period before saline administration. Moreover, saline infusion did not alter mean arterial pressure, pulse pressure, or esophageal temperature (all P > 0.05). To serve as a volume control, 15 ml/kg saline were rapidly infused intravenously in normothermic subjects. Saline infusion increased CVP (P 0.05). These data suggest that cardiopulmonary baroreceptor unloading during passive heating may attenuate the elevation in SkBF in humans, whereas loading cardiopulmonary baroreceptors in normothermia has no effect on SkBF.
Crandall et al. (Mon,) conducted a other in Healthy subjects (n=7). Intravenous warm saline infusion vs. Normothermic volume control was evaluated on Cutaneous vascular conductance and central venous pressure (p=<0.05). Rapid saline infusion (15 ml/kg) during passive heating restored central venous pressure and significantly increased cutaneous vascular conductance (P<0.05), unlike in normothermic controls.