What the study found
A prehospital cold water immersion protocol used by the Phoenix Fire Department was feasible in a large urban emergency medical services system. In the patients studied, it was associated with rapid temperature reduction and improved neurologic status.
Why the authors say this matters
The authors conclude that the findings suggest a meaningful clinical benefit and broad operational feasibility. They also say the results may help guide wider adoption of prehospital immersion cooling.
What the researchers tested
The researchers conducted a retrospective observational study of adults with heat stroke treated with the Phoenix Fire Department prehospital cold water immersion protocol from May 1 to September 30, 2024. They reviewed prehospital, emergency department, and inpatient data from EMS charts and electronic medical records across four hospital systems.
What worked and what didn't
Among 183 patients, the median prehospital tympanic temperature was 41.4 °C, and nearly one-third had temperatures above 42.2 °C. Median immersion time was 13.5 minutes, and temperature decreased from prehospital to emergency department arrival in 72.1% of patients, with an average decrease of 2.0 °C. Median Glasgow Coma Scale score increased from 8 before hospital arrival to 9 on arrival and 15 at discharge, and 69.4% of patients were discharged neurologically intact.
What to keep in mind
This was a retrospective observational study, so it describes outcomes in patients who received the protocol but does not test causation. The abstract also notes that survival decreased with increasing prehospital temperature and was lowest among those presenting at or above 42.2 °C, but it does not provide detailed comparative analyses or describe all limitations.
Key points
- The study examined 183 adults with heat stroke treated with prehospital cold water immersion.
- Temperature fell before emergency department arrival in 72.1% of patients, with an average drop of 2.0 °C.
- Median Glasgow Coma Scale scores improved from 8 prehospital to 15 at discharge.
- 69.4% of patients were discharged neurologically intact.
- Survival was lowest among patients whose prehospital temperature was at or above 42.2 °C.
Disclosure
- Research title:
- Prehospital cold water immersion lowered temperature in heat stroke patients
- Authors:
- Geoffrey Comp, Charles Finch, Kristina Kupanoff, Matthew Sandoval, Maki Lloyd, Narda Aldaco, David Kirk, Paul Pugsley, Lora Nordstrom, B. Witkind Koenig, A Narang, Jerry W. Snow, Matthew Kamer, Alexandria Foster, Grace Patel, Jeffrey R. Stowell
- Institutions:
- Banner – University Medical Center Phoenix, Banner Life Sciences (United States), Creighton University, Creighton University, Creighton University, Creighton University, Creighton University, Department of Education and Training, Health Net, Health Net, Healthwise, Healthwise, Healthwise, Healthwise, Healthwise, Naval Aerospace Medical Institute, Naval Medical Center San Diego, Naval Medical Research Command, New York City Fire Department, New York City Fire Department, New York City Fire Department, New York City Fire Department, Phoenix College, Phoenix College, Phoenix College, Phoenix College, Phoenix College, St. Joseph Medical Center, St. Joseph Medical Center in Tacoma, St. Joseph's Hospital and Medical Center, St. Joseph's Hospital and Medical Center, University of Arizona, University of Arizona, University of Arizona, University of Arizona, University of Arizona, University of Arizona, University of Arizona, University of Phoenix, University of Phoenix, University of Phoenix, University of Phoenix, University of Phoenix, University of Phoenix, Valley Medical Center, Valley Medical Center, Valley Medical Center, Valley Medical Center
- Publication date:
- 2026-03-05
- OpenAlex record:
- View
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