Safety and efficacy of cold‐water immersion in the treatment of older patients with heat stroke: a case series

Exercise conducted in hot, humid environments increases the risk for exertional heat stroke (EHS). The current recommended treatment of EHS is cold-water immersion; however, limitations may require the use of alternative resources such as a cold shower (CS) or dousing with a hose to cool EHS patients.Context: To investigate the cooling effectiveness of a CS after exercise-induced hyperthermia.Objective: Randomized, crossover controlled study.Design: Environmental chamber (temperature = 33.4°C ± 2.1°C; relative humidity = 27.1% ± 1.4%).Setting: Seventeen participants (10 male, 7 female; height = 1.75 ± 0.07 m, body mass = 70.4 ± 8.7 kg, body surface area = 1.85 ± 0.13 m2, age range = 19–35 years) volunteered.Patients or Other Participants: On 2 occasions, participants completed matched-intensity volitional exercise on an ergometer or treadmill to elevate rectal temperature to ≥39°C or until participant fatigue prevented continuation (reaching at least 38.5°C). They were then either treated with a CS (20.8°C ± 0.80°C) or seated in the chamber (control [CON] condition) for 15 minutes.Intervention(s): Rectal temperature, calculated cooling rate, heart rate, and perceptual measures (thermal sensation and perceived muscle pain).Main Outcome Measure(s): The rectal temperature (P = .98), heart rate (P = .85), thermal sensation (P = .69), and muscle pain (P = .31) were not different during exercise for the CS and CON trials (P > .05). Overall, the cooling rate was faster during CS (0.07°C/min ± 0.03°C/min) than during CON (0.04°C/min ± 0.03°C/min; t16 = 2.77, P = .01). Heart-rate changes were greater during CS (45 ± 20 beats per minute) compared with CON (27 ± 10 beats per minute; t16 = 3.32, P = .004). Thermal sensation was reduced to a greater extent with CS than with CON (F3,45 = 41.12, P < .001).Results: Although the CS facilitated cooling rates faster than no treatment, clinicians should continue to advocate for accepted cooling modalities and use CS only if no other validated means of cooling are available.Conclusions:

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Emergency Medical Service Directors’ Protocols for Exertional Heat Stroke

Medicina ◽

10.3390/medicina56100494 ◽

2020 ◽

Vol 56 (10) ◽

pp. 494

Author(s):

Michael R. Szymanski ◽

Samantha E. Scarneo-Miller ◽

M. Seth Smith ◽

Michelle L. Bruner ◽

Douglas J. Casa

Keyword(s):

Best Practices ◽

Emergency Medical Service ◽

Best Practice ◽

Medical Service ◽

Cold Water ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Athletic Trainer ◽

Chi Squared

Background and Objectives: Emergency Medical Service (EMS) protocols vary widely and may not implement best practices for exertional heat stroke (EHS). EHS is 100% survivable if best practices are implemented within 30 min. The purpose of this study is to compare EMS protocols to best practices for recognizing and treating EHS. Materials and Methods: Individuals (n = 1350) serving as EMS Medical or Physician Director were invited to complete a survey. The questions related to the EHS protocols for their EMS service. 145 individuals completed the survey (response rate = 10.74%). Chi-Squared Tests of Associations (χ2) with 95% confidence intervals (CI) were calculated. Prevalence ratios (PR) with 95% CI were calculated to determine the prevalence of implementing best practices based on location, working with an athletic trainer, number of EHS cases, and years of directing. All PRs whose 95% CIs excluded 1.00 were considered statistically significant; Chi-Squared values with p values < 0.05 were considered statistically significant. Results: A majority of the respondents reported not using rectal thermometry for the diagnosis of EHS (n = 102, 77.93%) and not using cold water immersion for the treatment of EHS (n = 102, 70.34%). If working with an athletic trainer, EMS is more likely to implement best-practice treatment (i.e., cold-water immersion and cool-first transport-second) (69.6% vs. 36.9%, χ2 = 8.480, p < 0.004, PR = 3.15, 95% CI = 1.38, 7.18). Conclusions: These findings demonstrate a lack of implementation of best-practice standards for EHS by EMS. Working with an athletic trainer appears to increase the likelihood of following best practices. Efforts should be made to improve EMS providers’ implementation of best-practice standards for the diagnosis and management of EHS to optimize patient outcomes.

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Cooling Effectiveness of a Modified Cold-Water Immersion Method After Exercise-Induced Hyperthermia

Journal of Athletic Training ◽

10.4085/1062-6050-51.12.07 ◽

2016 ◽

Vol 51 (11) ◽

pp. 946-951 ◽

Cited By ~ 22

Author(s):

Katherine E. Luhring ◽

Cory L. Butts ◽

Cody R. Smith ◽

Jeffrey A. Bonacci ◽

Ramon C. Ylanan ◽

...

Keyword(s):

Heart Rate ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Effect Size ◽

Cold Water ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Whole Body ◽

Exertional Heat Stroke

Context: Recommended treatment for exertional heat stroke includes whole-body cold-water immersion (CWI). However, remote locations or monetary or spatial restrictions can challenge the feasibility of CWI. Thus, the development of a modified, portable CWI method would allow for optimal treatment of exertional heat stroke in the presence of these challenges. Objective: To determine the cooling rate of modified CWI (tarp-assisted cooling with oscillation [TACO]) after exertional hyperthermia. Design: Randomized, crossover controlled trial. Setting: Environmental chamber (temperature = 33.4°C ± 0.8°C, relative humidity = 55.7% ± 1.9%). Patients or Other Participants: Sixteen volunteers (9 men, 7 women; age = 26 ± 4.7 years, height = 1.76 ± 0.09 m, mass = 72.5 ± 9.0 kg, body fat = 20.7% ± 7.1%) with no history of compromised thermoregulation. Intervention(s): Participants completed volitional exercise (cycling or treadmill) until they demonstrated a rectal temperature (Tre) ≥39.0°C. After exercise, participants transitioned to a semirecumbent position on a tarp until either Tre reached 38.1°C or 15 minutes had elapsed during the control (no immersion [CON]) or TACO (immersion in 151 L of 2.1°C ± 0.8°C water) treatment. Main Outcome Measure(s): The Tre, heart rate, and blood pressure (reported as mean arterial pressure) were assessed precooling and postcooling. Statistical analyses included repeated-measures analysis of variance with appropriate post hoc t tests and Bonferroni correction. Results: Before cooling, the Tre was not different between conditions (CON: 39.27°C ± 0.26°C, TACO: 39.30°C ± 0.39°C; P = .62; effect size = −0.09; 95% confidence interval [CI] = −0.2, 0.1). At postcooling, the Tre was decreased in the TACO (38.10°C ± 0.16°C) compared with the CON condition (38.74°C ± 0.38°C; P < .001; effect size = 2.27; 95% CI = 0.4, 0.9). The rate of cooling was greater during the TACO (0.14 ± 0.06°C/min) than the CON treatment (0.04°C/min ± 0.02°C/min; t15 = −8.84; P < .001; effect size = 2.21; 95% CI = −0.13, −0.08). These differences occurred despite an insignificant increase in fluid consumption during exercise preceding CON (0.26 ± 0.29 L) versus TACO (0.19 ± 0.26 L; t12 = 1.73; P = .11; effect size = 0.48; 95% CI = −0.02, 0.14) treatment. Decreases in heart rate did not differ between the TACO and CON conditions (t15 = −1.81; P = .09; effect size = 0.45; 95% CI = −22, 2). Mean arterial pressure was greater at postcooling with TACO (84.2 ± 6.6 mm Hg) than with CON (67.0 ± 9.0 mm Hg; P < .001; effect size = 2.25; 95% CI = 13, 21). Conclusions: The TACO treatment provided faster cooling than did the CON treatment. When location, monetary, or spatial restrictions are present, TACO represents an effective alternative to traditional CWI in the emergency treatment of patients with exertional hyperthermia.

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Chemically Activated Cooling Vest’s Effect on Cooling Rate Following Exercise-Induced Hyperthermia: A Randomized Counter-Balanced Crossover Study

Medicina ◽

10.3390/medicina56100539 ◽

2020 ◽

Vol 56 (10) ◽

pp. 539

Author(s):

Yuri Hosokawa ◽

Luke N. Belval ◽

William M. Adams ◽

Lesley W. Vandermark ◽

Douglas J. Casa

Keyword(s):

Cooling Rate ◽

Body Mass ◽

Cold Water ◽

Water Immersion ◽

Heat Stroke ◽

Cooling Capacity ◽

Cold Water Immersion ◽

Whole Body ◽

Climatic Chamber ◽

Exercise Induced

Background and objectives: Exertional heat stroke (EHS) is a potentially lethal, hyperthermic condition that warrants immediate cooling to optimize the patient outcome. The study aimed to examine if a portable cooling vest meets the established cooling criteria (0.15 °C·min−1 or greater) for EHS treatment. It was hypothesized that a cooling vest will not meet the established cooling criteria for EHS treatment. Materials and Methods: Fourteen recreationally active participants (mean ± SD; male, n = 8; age, 25 ± 4 years; body mass, 86.7 ± 10.5 kg; body fat, 16.5 ± 5.2%; body surface area, 2.06 ± 0.15 m2. female, n = 6; 22 ± 2 years; 61.3 ± 6.7 kg; 22.8 ± 4.4%; 1.66 ± 0.11 m2) exercised on a motorized treadmill in a hot climatic chamber (ambient temperature 39.8 ± 1.9 °C, relative humidity 37.4 ± 6.9%) until they reached rectal temperature (TRE) >39 °C (mean TRE, 39.59 ± 0.38 °C). Following exercise, participants were cooled using either a cooling vest (VEST) or passive rest (PASS) in the climatic chamber until TRE reached 38.25 °C. Trials were assigned using randomized, counter-balanced crossover design. Results: There was a main effect of cooling modality type on cooling rates (F[1, 24] = 10.46, p < 0.01, η2p = 0.30), with a greater cooling rate observed in VEST (0.06 ± 0.02 °C·min−1) than PASS (0.04 ± 0.01 °C·min−1) (MD = 0.02, 95% CI = [0.01, 0.03]). There were also main effects of sex (F[1, 24] = 5.97, p = 0.02, η2p = 0.20) and cooling modality type (F[1, 24] = 4.38, p = 0.047, η2p = 0.15) on cooling duration, with a faster cooling time in female (26.9 min) than male participants (42.2 min) (MD = 15.3 min, 95% CI = [2.4, 28.2]) and faster cooling duration in VEST than PASS (MD = 13.1 min, 95% CI = [0.2, 26.0]). An increased body mass was associated with a decreased cooling rate in PASS (r = −0.580, p = 0.03); however, this association was not significant in vest (r = −0.252, p = 0.39). Conclusions: Although VEST exhibited a greater cooling capacity than PASS, VEST was far below an acceptable cooling rate for EHS treatment. VEST should not replace immediate whole-body cold-water immersion when EHS is suspected.

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Should Cooling Vests Be Used to Treat Exertional Heatstroke? A Critically Appraised Topic

Journal of Sport Rehabilitation ◽

10.1123/jsr.2015-0082 ◽

2017 ◽

Vol 26 (3) ◽

pp. 286-289

Author(s):

Megan L. Keen ◽

Kevin C. Miller

Keyword(s):

Cold Water ◽

Core Body Temperature ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Clinical Scenario ◽

Clinical Question ◽

Bottom Line ◽

Cooling Rates ◽

Central Nervous System Dysfunction

Clinical Scenario:Exercise performed in hot and humid environments increases core body temperature (TC). If TC exceeds 40.5°C for prolonged periods of time, exertional heat stroke (EHS) may occur. EHS is a leading cause of sudden death in athletes. Mortality and morbidity increase the longer the patient’s TC remains above 40.5°C; thus, it is imperative to initiate cooling as quickly as possible. Acceptable cooling rates in EHS situations are 0.08–0.15°C/min, while ideal cooling rates are above 0.16°C/min. Cooling vests are popular alternatives for cooling hyperthermic adults. Most vests cover the anterior and posterior torso and have varying numbers of pouches for phase-change materials (eg, gel packs); some vests only use circulating water to cool. While cooling vests offer several advantages (eg, portability), studies demonstrating their effectiveness at rapidly reducing TC in EHS scenarios are limited.Clinical Question:Are TC cooling rates acceptable (ie, >0.08°C/min) when hyperthermic humans are treated with cooling vests postexercise?Summary of Findings:No significant differences in TC cooling rates occurred between cooling vests and no cooling vests. Cooling rates across all studies were ≤0.053°C/min.Clinical Bottom Line:Cooling vests do not provide acceptable cooling rates of hyperthermic humans postexercise and should not be used to treat EHS. Instead, EHS patients should be treated with cold-water immersion within 30 min of collapse to avoid central nervous system dysfunction and organ failure.Strength of Recommendation:Strong evidence (eg, level 2 studies with PEDro scores ≥5) suggests that cooling vests do not reduce TC quickly and thus should not be used in EHS scenarios.

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Cold Water Immersion For Exertional Heat Stroke At 33 New England Road Races, 2011-2019

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000763580.83031.7e ◽

2021 ◽

Vol 53 (8S) ◽

pp. 372-372

Author(s):

Rebecca G. Breslow ◽

Ying H. Yang ◽

Jamie E. Collins

Keyword(s):

New England ◽

Cold Water ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Exertional Heat Stroke ◽

Road Races

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Athletic Trainers' Attitudes and Perceptions Regarding Exertional Heat Stroke Before and After an Educational Intervention

Athletic Training Education Journal ◽

10.4085/1203179 ◽

2017 ◽

Vol 12 (3) ◽

pp. 179-187 ◽

Cited By ~ 2

Author(s):

Kristen Couper Schellhase ◽

Jennifer Plant ◽

Stephanie M. Mazerolle

Keyword(s):

Educational Intervention ◽

Cold Water ◽

Core Body Temperature ◽

Athletic Trainers ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Attitudes And Perceptions ◽

Before And After ◽

Core Body

Context: Death from exertional heat stroke (EHS) is preventable when evidence-based guidelines are followed. The assessment of core body temperature using rectal thermometry and the treatment of cold-water immersion for EHS has been established as the standard of care; however, rectal thermometry is still controversial. Athletic trainers (ATs) may lack knowledge and comfort with this skill, which could impact implementation. Objective: Examine ATs' current practices, attitudes, and perceptions regarding EHS before and after an educational intervention. Design: Prequantitative/postquantitative experimental. Setting: Classroom. Patients or Other Participants: Twenty-five ATs in various athletic training settings. Intervention(s): Educational intervention designed to increase knowledge and address negative attitudes and perceptions regarding EHS evaluation and treatment. Main Outcome Measure(s): Attitude and perception scores. Results: Prior to the educational intervention, most ATs (86.9%, 20/23) reported that they use methods other than rectal thermometry to evaluate EHS. Of those who did not use rectal thermometry, their reasons included: lack of equipment/budget, concerns about liability/lack of consent (especially when dealing with minors), lack of training, and/or concerns about the privacy, embarrassment, compliance of the athlete. Cold-water immersion was chosen as the definitive method of cooling an athlete by only 41.7% (n = 10) of participants. Following the educational intervention, attitudes toward the use of rectal temperature to assess core body temperature (t[24] = 8.663, P < .001) and cold-water immersion treatment for EHS (t[24] = 4.187, P < .001) were significantly improved. However, while attitudes toward the use of other “cold” methods to treat EHS were not significantly changed (t[24] = 1.684, P = .105), perceptions regarding nonexertional influences on EHS were significantly improved (t[24] = 1.684, P = .105). Conclusions: This study demonstrated that a 3-hour educational intervention can improve attitudes and perceptions regarding the assessment and treatment of EHS in the short term. It is important that educational interventions use best-practice continuing education methods and include special attention to the barriers to evidence-based practice.

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Proper Recognition and Management of Exertional Heat Stroke in a High School Cross Country Runner: A Validation Clinical Case Report

Journal of Athletic Training ◽

10.4085/1062-6050-462-21 ◽

2021 ◽

Author(s):

Bryanna Garrett ◽

Rebecca Lopez ◽

Michael Szymanski ◽

Drew Eidt

Keyword(s):

High School ◽

Cold Water ◽

Action Plan ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Exertional Heat Stroke ◽

Difficulty Breathing ◽

History Of ◽

Cross Country

A 14-year-old female high school cross country runner (height = 154 cm, mass = 48.1 kg) with no history of exertional heat stroke (EHS) collapsed at the end of a race. An athletic trainer (AT) assessed the patient, who presented with difficulty breathing then other signs of EHS (i.e. confusion, agitation). The patient was taken to the medical area, draped with a towel, and a rectal temperature (Tre) of 106.9°F(41.6°C) was obtained. The emergency action plan was activated and emergency medical services (EMS) were called. The patient was submerged in a cold-water immersion tub until EMS arrived (~15 minutes; Tre = 100.1°F; cooling rate: 0.41°F·min−1[0.25°C·min−1]). At the hospital, the patient received intravenous fluids, and urine and blood tests were normal. The patient was not admitted and returned to running without sequelae. Following best practices, AT's in secondary schools can prevent death from EHS by properly recognizing EHS and providing rapid cooling before transport.

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Current Knowledge, Attitudes, and Practices of Certified Athletic Trainers Regarding Recognition and Treatment of Exertional Heat Stroke

Journal of Athletic Training ◽

10.4085/1062-6050-45.2.170 ◽

2010 ◽

Vol 45 (2) ◽

pp. 170-180 ◽

Cited By ~ 33

Author(s):

Stephanie M. Mazerolle ◽

Ian C. Scruggs ◽

Douglas J. Casa ◽

Laura J. Burton ◽

Brendon P. McDermott ◽

...

Keyword(s):

Cold Water ◽

Current Knowledge ◽

Athletic Trainers ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Exertional Heat Stroke ◽

Certified Athletic Trainers ◽

Attitudes And Practices ◽

Knowledge Attitudes And Practices

Abstract Context: Previous research has indicated that despite awareness of the current literature on the recommended prevention and care of exertional heat stroke (EHS), certified athletic trainers (ATs) acknowledge failure to follow those recommendations. Objective: To investigate the current knowledge, attitudes, and practices of ATs regarding the recognition and treatment of EHS. Design: Cross-sectional study. Setting: Online survey. Patients or Other Participants: We obtained a random sample of e-mail addresses for 1000 high school and collegiate ATs and contacted these individuals with invitations to participate. A total of 498 usable responses were received, for a 25% response rate. Main Outcome Measure(s): The survey instrument evaluated ATs' knowledge and actual practice regarding EHS and included 29 closed-ended Likert scale questions (1 = strongly disagree, 7 = strongly agree), 2 closed-ended questions rated on a Likert scale (1 = lowest value, 9 = greatest value), 8 open-ended questions, and 7 demographic questions. We focused on the open-ended and demographic questions. Results: Although most ATs (77.1%) have read the current National Athletic Trainers' Association position statement on heat illness, only 18.6% used rectal thermometers to assess core body temperature to recognize EHS, and 49.7% used cold-water immersion to treat EHS. Athletic trainers perceived rectal thermometers as the most valid temperature assessment device when compared with other assessment devices (P ≤ .05), but they used oral thermometers as the primary assessment tool (49.1%). They identified cold-water immersion as the best cooling method (P ≤ .05), even though they used other means to cool a majority of the time (50.3%). Conclusions: The ATs surveyed have sound knowledge of the correct means of EHS recognition and treatment. However, a significant portion of these ATs reported using temperature assessment devices that are invalid with athletes exercising in the heat. Furthermore, they reported using cooling treatment methods that have inferior cooling rates.

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