Face cooling increases blood pressure during central hypovolemia (2017)
Face cooling increases blood pressure during central hypovolemia
Blair D. Johnson, James R. Sackett, Suman Sarker, and Zachary J. SchladerAmerican Journal of Physiology-Regulatory, Integrative and Comparative Physiology 2017 313:5, R594-R600
A reduction in central blood volume can lead to cardiovascular decompensation (i.e., failure to maintain blood pressure). Cooling the forehead and cheeks using ice water raises blood pressure. Therefore, face cooling (FC) could be used to mitigate decreases in blood pressure during central hypovolemia.
We tested the hypothesis that FC during central hypovolemia induced by lower-body negative pressure (LBNP) would increase blood pressure. Ten healthy participants (22 ± 2 yr, three women, seven men) completed two randomized LBNP trials on separate days. Trials began with 30 mmHg of LBNP for 6 min. Then, a 2.5-liter plastic bag of ice water (0 ± 0°C) (LBNP+FC) or thermoneutral water (34 ± 1°C) (LBNP+Sham) was placed on the forehead, eyes, and cheeks during 15 min of LBNP at 30 mmHg. Forehead temperature was lower during LBNP+FC than LBNP+Sham, with the greatest difference at 21 min of LBNP (11.1 ± 1.6 vs. 33.9 ± 1.4°C, P < 0.001). Mean arterial pressure was greater during LBNP+FC than LBNP+Sham, with the greatest difference at 8 min of LBNP (98 ± 15 vs. 80 ± 8 mmHg, P < 0.001). Cardiac output was higher during LBNP+FC than LBNP+Sham with the greatest difference at 18 min of LBNP (5.9 ± 1.4 vs. 4.9 ± 1.0 liter/min, P = 0.005). Forearm cutaneous vascular resistance was greater during LBNP+FC than LBNP+Sham, with the greatest difference at 15 min of LBNP (7.2 ± 3.4 vs. 4.9 ± 2.7 mmHg/perfusion units (PU), P < 0.001).
Face cooling during LBNP increases blood pressure through increases in cardiac output and vascular resistance.
Article Highlights:
- “Blood loss and other clinical situations (e.g., postural orthostatic intolerance, sepsis, and Dengue fever) can cause central hypovolemia and lead to cardiovascular decompensation (i.e., inability to maintain blood pressure).”
- “Intravenous saline infusions are common in the prehospital setting to counteract central hypovolemia.
- However, intravenous saline infusions increase the risk of coagulopathy and necessary blood transfusions in trauma patients.
- Furthermore, this method requires venous access, which can be difficult to obtain during central hypovolemia”
- “Cooling the forehead and cheeks stimulates the trigeminal nerve, which elicits an increase in cardiac parasympathetic activity followed by a rise in sympathetic activity.”
- “Despite the transient increase in cardiac parasympathetic activity, face cooling causes substantial increases in blood pressure that can be maintained for 15 min or more.”
- “Therefore, simply cooling the forehead and cheeks might be an effective intervention to maintain or improve blood pressure in individuals during acute periods of central hypovolemia.”
- “The main finding of this study is that face cooling facilitated a rapid increase in mean arterial pressure that was sustained throughout 15 min..”
- “The increase in mean arterial pressure during face cooling was accomplished by a combination of increases in cardiac output and skin vascular resistance.”
“These findings indicate that face cooling is able to augment mean arterial pressure… which suggests that this technique could be employed as a tool to prevent or delay cardiovascular decompensation during central hypovolemia.”
