Treatment of Exertional Heatstroke witH icE wAter Soaked Towels (THE HEAT)

Exertional heat stroke (EHS) is the most serious form of heat-illness that can occur during sports and exercise. If not recognized and treated immediately mortality rate of EHS is high. Early recognition and initiation of cooling are paramount. If temperature is reduced to < 40°C within 30 minutes of symptom onset, most patients recover completely. There are several strategies for cooling in EHS, including cooling with rotating in ice water soaked towels which cover the body of a patient.

The aim of this research is to investigate the effectiveness and safety of treatment of EHS with ice water soaked towels to lower body temperature.

Study Overview

• Status: Active, not recruiting
• Conditions: Heat Illness; Heat Exhaustion; Heat Stroke Exertional
• Intervention / Treatment: Other: There is no intervention, only observational study

Detailed Description

Rationale: Exertional heat stroke (EHS) is the most serious form of heat-illness that can occur during sports and exercise. If not recognized and treated immediately mortality rate of EHS is high. Early recognition and initiation of cooling are paramount. If temperature is reduced to < 40°C within 30 minutes of symptom onset, most patients recover without sequelae. Exertional heat exhaustion (EHE) is a precursor of EHS, and might develop in EHS if exercise is not terminated. There are several strategies for cooling in EHS, including cooling with rotating in ice water soaked towels which cover the body of a patient.

Objective: The aim of this research is to investigate the effectiveness and safety of treatment of EHS with ice water soaked towels to lower body temperature. Secondary objectives include cooling rate of ice water soaked towels, morbidity of EHS and HE, productivity loss related to EHS and EHE and the development of posttraumatic stress symptoms and PTSD after treatment for EHS and EHE.

Study design: We will conduct a prospective longitudinal observational study. Patients will be monitored and treated according the national guideline in the medical facility. A follow-up survey will be performed after two weeks and two months.

Study population: All participants of 18 years and older who received medical care for EHS or EHE at the City Pier City race on March 12th 2023 and Rotterdam Marathon on April 16th 2023.

Main study parameters/endpoints: Primary outcome will be the cooling rate of treatment with rotating in ice water soaked towels. Secondary outcomes will be percentage of patients with EHS that were cooled to a temperature lower than 40°C within 30 minutes after entering a medical facility (or collapse).

Hypothesis: Cooling with rotating in ice water soaked towels is an effective method for cooling patients with EHS by reducing the body temperature < 40°C within 30 minutes after symptoms.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: There will be no risk from participating in the study and the burden will be low. The questionnaire will take approximately 20-30 minutes at two weeks and two months and 15 minutes at six months.

• Study Type: Observational
• Enrollment (Estimated): 55

Contacts and Locations

Study Locations

• Netherlands
  • Zuid-Holland
    • Rotterdam, Zuid-Holland, Netherlands, 3015GD
      • Erasmus MC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Adult runners who received medical care for EHS of EHE in the medical facility at the running events organized by Golazo Sports® at the City Pier City and Marathon Rotterdam 2023.

Description

Inclusion Criteria:

In order to be eligible to participate in this study, a subject must meet all of the following criteria:

• ≥18 years
• Receive medical care at in the medical facility the City Pier City and Marathon Rotterdam 2023
• Tympanic temperature >38.0°C

Exclusion Criteria:

A potential subject who meets any of the following criteria will be excluded from participation in this study:

• Language barrier (not proficient in Dutch or English)

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
cooling rate	cooling rate of treatment with rotating in ice water soaked towels	during treatment in medical facility up to 2 hours after entering the facility

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
percentage cooled to a temperature <40°C within 30 minutes	be percentage of patients with EHS that were cooled to a temperature lower than 40°C within 30 minutes after entering a medical facility (or collapse).	30 minutes after entering medical facility
Morbidity of EHS/EHE	Morbidity of EHS and HE, clinical disease measured by questionnaires	2 weeks and 2 months after EHS/EHE
Posttraumatic stress symptoms after EHS and EHE	Posttraumatic stress symptoms and PTSD after treatment for EHS and EHE by PCL-5 questionnaire.	6 months after EHS/EHE
productivity loss (abscens of work) related to EHS and EHE	Productivity loss measured by abscens of work questionnaire	2 months after EHS/EHE

Collaborators and Investigators

• Sponsor: Erasmus Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): March 12, 2023
• Primary Completion (Estimated): October 31, 2025
• Study Completion (Estimated): October 31, 2025

Study Registration Dates

• First Submitted: January 19, 2023
• First Submitted That Met QC Criteria: January 29, 2023
• First Posted (Actual): February 8, 2023

Study Record Updates

• Last Update Posted (Actual): August 7, 2025
• Last Update Submitted That Met QC Criteria: August 4, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Heat Stress Disorders; Heat Stroke; Heat Exhaustion
• Other Study ID Numbers: 9805 (Fred Hutch/University of Washington Cancer Consortium)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No