Body Cooling in Hyperthermic Males and Females

Efficacy of the Polar Breeze Thermal Rehabilitation Machine in Cooling Recreationally Active Males and Females Following Exercise-induced Hyperthermia

Exertional heat stroke (EHS) is an emergency medical condition that is prevalent in military soldiers, athletes, and laborers. It is diagnosed when the rectal temperature is above 40°C with the presence of central nervous dysfunction (altered mental status). The gold standard method of care for EHS is immediate onsite whole body cooling using cold-water immersion (cooling rates >0.15°C•min-1), which is reported to have the highest cooling rate. In the treatment of EHS, selecting a cooling modality with a high cooling rate becomes crucial to minimize the time above the critical threshold of body temperature at 40°C to less than 30 minutes for the best chance of survival and to minimize the severity of prognosis. However, in situations where cold water immersion is not feasible (in certain military, firefighter, or other remote settings), other cooling modalities must be available that have a cooling capacity similar to that of cold-water immersion. In this proposed study, we aim to compare the cooling rates of the Polar Breeze® (developed by Polar Breeze ®, Clearwater, FL), cold-water immersion (the current gold standard for EHS treatment), and passive cooling in individuals with exercise-induced hyperthermia

Study Overview

• Status: Completed
• Conditions: Cryotherapy Effect
• Intervention / Treatment: Device: Thermal Rehabilitation Machine; Other: Cold Water Immersion

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Greensboro, North Carolina, United States, 27412
      • University of North Carolina at Greensboro

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• males and females between the ages of 18-35.
• recreationally active (regularly exercise at a minimum of 4-5 times per week for greater than 30 minutes per session)

Exclusion Criteria:

• chronic health problems
• fever or current illness at the time of testing
• history of cardiovascular, metabolic, or respiratory disease
• current musculoskeletal injury that limits physical activity
• history of exertional heat illness in the past three years

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Thermal rehab machine; Participants, following exercise-induced hyperthermia, will be cooled using a Thermal Rehab Machine (Polar Breeze, Statim Technologies, LLC, Clearwater Florida), which is a micro-environmental air chiller. The device will be placed over the subjects head and through trans pulmonary cooling, will cool the body.	Device: Thermal Rehabilitation Machine; The Polar Breeze unit is a microenvironmental air-chiller. That means it is a single-pass air-conditioner capable of cooling external air; Other Names: Polar Breeze
No Intervention: Passive Cooling; Participants, following exercise-induced hyperthermia, will undergo a period of passive rest to allow the body to cool via natural mechanisms of evaporation of sweat from the skin's surface and convection
Active Comparator: Cold Water Immersion; Participants, following exercise-induced hyperthermia, will be cooled using cold water immersion. Participants will be immersed up to their chest in cold water (~50-55 Degrees Fahrenheit).	Other: Cold Water Immersion; Whole-body immersion in cold water.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Internal Body Temperature	The rate at which body temperature is reduced during whole body cooling following exercise-induced hyperthermia.	0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 minutes post onset of cooling

Collaborators and Investigators

• Sponsor: University of North Carolina, Greensboro

Study record dates

Study Major Dates

• Study Start (Actual): November 20, 2019
• Primary Completion (Actual): March 31, 2020
• Study Completion (Actual): March 31, 2020

Study Registration Dates

• First Submitted: December 3, 2019
• First Submitted That Met QC Criteria: December 4, 2019
• First Posted (Actual): December 9, 2019

Study Record Updates

• Last Update Posted (Actual): April 8, 2020
• Last Update Submitted That Met QC Criteria: April 7, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: A20-0085

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