Exercise in Burn Survivors: Cooling Modalities

Study Overview
=================
Brief Summary
-----------------
This project will identify the efficacy of cooling modalities aimed to attenuate excessive elevations in skin and internal body temperatures during physical activity in well-healed burn survivors. The investigators will conduct a randomized crossover design study. Non-burned control subjects, subjects who experienced burns covering  20% to 40% of their body surface area, and subject having burns >40% of their body surface area will be investigated. Subjects will exercise in heated environmental conditions while receiving the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of fan and skin wetting.

Detailed Description
-----------------
Within the United States, 500,000+ individuals are enduring the long-term consequences of severe burn injuries covering 20% or more of their body surface area, with upwards to 11,000 individuals experiencing such an injury per year. These burn injuries can severely compromise body temperature regulation, owing to permanent impairments in the primary thermoeffectors necessary to dissipate heat, namely profoundly blunted skin blood flow and sweating responses in the injured skin. The investigators propose that this heat intolerance deters burn survivors from participating in physical activity, including activities of daily living, necessary to avoid the adverse cardiovascular and metabolic sequela of a sedentary lifestyle. Consistent with hypothesis, years after the injury burn survivors have a very low aerobic capacity; greater all-cause mortality rates; greater hospitalization days for circulatory diseases; and suffer from greater incidences of ischemic heart disease, heart failure, diabetes, and cerebrovascular disease (including stroke) relative to matched non-burned cohorts. The primary goal of this project is to identify modalities to attenuate excessive elevations in skin and core body temperatures during physical activity in well-healed burn survivors. The implementation of such modalities will eliminate heat intolerance as a barrier to participation in activities that are necessary to improve/maintain cardiovascular health in this vulnerable population. This project will investigate whether increased skin wetness, with and without accompanying fan use, will restore otherwise impaired evaporative cooling of well-healed burn survivors, with the extent of that improvement predicated on the environmental conditions and the percentage of body surface area burned.

Official Title
-----------------
Exercise in Burn Survivors: Cooling Modalities

Conditions
-----------------
Burn Injury

Intervention / Treatment
-----------------
* Other: Cooing Modalities


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria (non-burned individuals): Healthy male and female subjects 18-65 years of age. Free of any underlying medical conditions Exclusion Criteria (non-burned individuals): Any burn-related injuries resulting in at least one night of hospitalization. Heart disease or any other chronic medical condition requiring regular medical therapy including cancer, diabetes, and hypertension. Abnormalities detected on routine screening Individuals who participate in a structured aerobic exercise training program at moderate to high intensities. Current smokers, as well as individuals who regularly smoked within the past 3 years. Body mass index of greater than 30 kg/m^2. Pregnant individuals Inclusion Criteria (burn survivors): Healthy male and female subjects 18-65 years of age. Free of any underlying medical conditions Having a burn injury covering 20-40% or >40% of the participant's body surface area; at least 50% of those burn injuries must be full thickness that required skin grafting. Participants must have been hospitalized due to the burn injury for a minimum of 15 days Exclusion Criteria (burn survivors): Any burn-related injuries resulting in at least one night of hospitalization. Heart disease or any other chronic medical condition requiring regular medical therapy including cancer, diabetes, and hypertension. Abnormalities detected on routine screening Individuals who participate in a structured aerobic exercise training program at moderate to high intensities. Current smokers, as well as individuals who regularly smoked within the past 3 years. Body mass index of greater than 30 kg/m^2. Pregnant individuals Extensive unhealed injured skin

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: The investigators will conduct a randomized crossover design study. Burn survivors and non-burned individuals, will each perform four bouts of 60-min of exercise trials with each bout incorporating the following cooling strategy: A) a control trial, B) skin wetting only trial, C) fan only trial, and D) a combination of skin wetting with a fan trial. Subjects will perform these four bouts under one of the following environmental conditions (24 deg C, 30 deg C, and 38 deg C). A subject will only be required to perform exercise across all four cooling modalities for a given environmental temperature (i.e., four exercise bouts); each will not be required to perform exercise across all combinations of environmental temperatures and cooling modalities (i.e., 12 exercise bouts).
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 24 deg C environment<br>Subjects will exercise for 60 minutes in a 24 deg C environment while being exposed to each of the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of a fan and skin wetting. | Other: Cooing Modalities<br>* Subjects will exercise for 60 minutes in the indicated environmental condition while being exposed to each of the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of a fan and skin wetting. A fan will be a commercially available fan will be directed to the research subject throughout the exercise bout. Skin wetting will be performed by spraying water onto the well-healed grafted skin throughout the exercise bout. A combination of a fan and skin wetting will be performed by simultaneously applying both cooling modalities throughout the exercise bout.<br>|
| Experimental: 30 deg C environment<br>Subjects will exercise for 60 minutes in a 24 deg C environment while being exposed to each of the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of a fan and skin wetting. | Other: Cooing Modalities<br>* Subjects will exercise for 60 minutes in the indicated environmental condition while being exposed to each of the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of a fan and skin wetting. A fan will be a commercially available fan will be directed to the research subject throughout the exercise bout. Skin wetting will be performed by spraying water onto the well-healed grafted skin throughout the exercise bout. A combination of a fan and skin wetting will be performed by simultaneously applying both cooling modalities throughout the exercise bout.<br>|
| Experimental: 38 deg C environment<br>Subjects will exercise for 60 minutes in a 24 deg C environment while being exposed to each of the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of a fan and skin wetting. | Other: Cooing Modalities<br>* Subjects will exercise for 60 minutes in the indicated environmental condition while being exposed to each of the following cooling modalities: no cooling, fan only, skin wetting only, and a combination of a fan and skin wetting. A fan will be a commercially available fan will be directed to the research subject throughout the exercise bout. Skin wetting will be performed by spraying water onto the well-healed grafted skin throughout the exercise bout. A combination of a fan and skin wetting will be performed by simultaneously applying both cooling modalities throughout the exercise bout.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Core body temperature will be measured from gastrointestinal temperature via an ingestible telemetric pill. | During exercise, one's core body temperature will increase. This device will measure this increase in core body temperature throughout the exercise. | Prior to and throughout each bout of exercise; an average of 120 minutes. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Skin temperature will be measured from small temperature sensitive electrodes attached to the participant's skin. | During exercise, one's skin temperature will increase. This device will measure this increase in skin temperature throughout the exercise. | Prior to and throughout each bout of exercise; an average of 120 minutes. | 
| Heart rate will be measured from ECG electrodes attached to the participant. | During exercise, one's heart rate will increase. This device will measure this increase in heart rate throughout the exercise. | Prior to and throughout each bout of exercise; an average of 120 minutes. | 
| Arterial blood pressure will be measured using a standard arm blood pressure cuff. | During exercise, one's blood pressure will increase. This device will measure this increase in blood pressure throughout the exercise. | Prior to and throughout each bout of exercise; an average of 120 minutes. | 
| Cardiac output (how much blood is ejected from the heart) will be measured using a nitrous oxide rebreathing approach. | During exercise, one's cardiac output will increase. This device will measure this increase in cardiac output throughout the exercise. | Prior to and throughout each bout of exercise; an average of 120 minutes. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
skin graft, thermoregulation, burn survivor, 3rd degree burn injury, human