Effects of Face Immersion in Cold Water on Blood Pressure and Cerebral Conductance

Abstract

Cold‐water face immersion without breath holding gives a gasp response followed by a dive response (DR). The DR after cold‐water face immersion elicits an increase in mean arterial blood pressure (MAP) but it is not evident if cerebral perfusion is maintained during this face immersion. Cerebral auto‐regulation suggests that cerebral perfusion is maintained during substantial variations in MAP. It was hypothesized that cold water face immersion would give changes in MAP that are inversely proportional to face temperatures and this would be coupled with maintenance of the index of cerebral conductance (CVCI, cm/s/mm Hg) in the middle cerebral (MCA) and vertebral arteries (VA). Five college‐age males of normal height and weight volunteered for the study. Physiological responses were assessed with B X B metabolic cart for pulmonary ventilation (VE), thermocouples for skin temperatures (TSK), a pulse oximeter for heart rate (HR), a transcranial‐Doppler monitor for cerebral blood velocity (CBV) and a Finometer for blood pressure. Five min face immersions were in water at 5, 15, and 33°C. Outcome variables were analyzed with a 1‐factor ANOVA with levels at each water temperature; 2‐tailed, paired t‐tests were employed for post‐hoc analyses with p=0.05. The results demonstrated elevations (p<0.05) in MAP from ~ 76 mm Hg at rest to the range of ~ 90 to 82 mm Hg in 5°C to 33°C water. Relative to rest the CVCI MCA (p<0.05) decreased by ~23% in the 5°C, by ~19% in the 15°C, and by ~12% in the 33°C immersions. In conclusion, these results support during cold‐water immersion without breath holding that face skin temperature responses were inversely proportional to blood pressure responses and proportional cerebral conductance responses.