Evaluation of Various Cooling Systems After Exercise-Induced Hyperthermia
- 1 February 2017
- journal article
- research article
- Published by Journal of Athletic Training/NATA in Journal of Athletic Training
- Vol. 52 (2), 108-116
- https://doi.org/10.4085/1062-6050-52.1.11
Abstract
Context: Rapid diagnosis and expeditious cooling of individuals with exertional heat stroke is paramount for survival. Objective: To evaluate the efficacy of various cooling systems after exercise-induced hyperthermia. Design: Crossover study. Setting: Laboratory. Patients or Other Participants: Twenty-two men (age = 24 ± 2 years, height = 1.76 ± 0.07 m, mass = 70.7 ± 9.5 kg) participated. Intervention(s): Each participant completed a treadmill walk until body core temperature reached 39.50°C. The treadmill walk was performed at 5.3 km/h on an 8.5% incline for 50 minutes and then at 5.0 km/h until the end of exercise. Each participant experienced 4 cooling phases in a randomized, repeated-crossover design: (1) no cooling (CON), (2) body-cooling unit (BCU), (3) EMCOOLS Flex.Pad (EC), and (4) ThermoSuit (TS). Cooling continued for 30 minutes or until body core temperature reached 38.00°C, whichever occurred earlier. Main Outcome Measure(s): Body core temperature (obtained via an ingestible telemetric temperature sensor) and heart rate were measured continuously during the exercise and cooling phases. Rating of perceived exertion was monitored every 5 minutes during the exercise phase and thermal sensation every minute during the cooling phase. Results: The absolute cooling rate was greatest with TS (0.16°C/min ± 0.06°C/min) followed by EC (0.12°C/min ± 0.04°C/min), BCU (0.09°C/min ± 0.06°C/min), and CON (0.06°C/min ± 0.02°C/min; P < .001). The TS offered a greater cooling rate than all other cooling modalities in this study, whereas EC offered a greater cooling rate than both CON and BCU (P < .0083 for all). Effect-size calculations, however, showed that EC and BCU were not clinically different. Conclusion: These findings provide objective evidence for selecting the most effective cooling system of those we evaluated for cooling individuals with exercise-induced hyperthermia. Nevertheless, factors other than cooling efficacy need to be considered when selecting an appropriate cooling system.Keywords
This publication has 40 references indexed in Scilit:
- Strategic target temperature management in myocardial infarction—a feasibility trialHeart, 2013
- Cold-Water Immersion and the Treatment of Hyperthermia: Using 38.6°C as a Safe Rectal Temperature Cooling LimitJournal of Athletic Training, 2010
- Rapid induction of therapeutic hypothermia using convective-immersion surface cooling: Safety, efficacy and outcomesResuscitation, 2010
- Current Knowledge, Attitudes, and Practices of Certified Athletic Trainers Regarding Recognition and Treatment of Exertional Heat StrokeJournal of Athletic Training, 2010
- The use of emergency medical cooling system pads in the treatment of malignant hyperthermiaEuropean Journal of Anaesthesiology, 2010
- Acute Whole-Body Cooling for Exercise-Induced Hyperthermia: A Systematic ReviewJournal of Athletic Training, 2009
- The Influence of Ethnicity on Thermoregulation After Acute Cold ExposureWilderness & Environmental Medicine, 2008
- Heat StrokeSports Medicine, 2004
- Treatment of Comatose Survivors of Out-of-Hospital Cardiac Arrest with Induced HypothermiaThe New England Journal of Medicine, 2002
- Prediction of lean body mass from height and weightJournal of Clinical Pathology, 1966