None listed
Conditions
Brief summary
This study aims to identify the most appropriate cooling strategy for older adults with and without hypertension during a simulated hot and dry heatwave (45°C and 15% relative humidity) Research questions: The primary research question guiding this project is: 1. Are fans and/or skin-wetting effective in decreasing the physiological strain experienced by elderly during a simulated hot, dry heatwave (45°C and 15% relative humidity) The research hypotheses going into this study are: 1. All interventions will result in reductions in thermal and cardiovascular strain compared to no intervention (control) With fan and skin-wetting (FSW) being the most effective, then no fan and skin-wetting (NFSW), then fan (F), and finally, the control, no-fan (NF).
Interventions
Intervention
Each participant will take part in four three hour exposures which be randomised;
1. No fan with no skin wetting (comparator)
2. Fan use with no skin wetting
3. No fan use with skin wetting
4. Fan use with skin wetting
They will be asked to sit in a thermally regulated environmental chamber at a temperature of 45°C and 15% relative humidity.
In all fan exposures, participants will be seated 1.25m from an 18" diameter fan with an airflow of ~4.0m/s. This is the velocity of a ty
Intervention Each participant will take part in four three hour exposures which be randomised; 1. No fan with no skin wetting (comparator) 2. Fan use with no skin wetting 3. No fan use with skin wetting 4. Fan use with skin wetting They will be asked to sit in a thermally regulated environmental chamber at a temperature of 45°C and 15% relative humidity. In all fan exposures, participants will be seated 1.25m from an 18" diameter fan with an airflow of ~4.0m/s. This is the velocity of a typical fan at highest speed. For the skin wetting exposures, approx 770mL, 18ºC tap water will be applied to the skin using a commercially available spray bottle to the face, neck, arms and legs by a researcher. Additionally, in all exposures they will be given cold (~18ºC) water equivalent to 1ml per kg of body weight every 20 minutes in an attempt to offset dehydration. There will be a minimum of 72 hours washout between each exposure.
Sponsors
University of Sydney
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
60 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Non smokers (or at least 1 year since quitting) Over 60 years of age Controlled hypertension or healthy older adult
Exclusion criteria
Oestrogen therapy Fluid or electrolyte disorders Anaemia Abnormal thyroid function Arrhythmias Diabetes Renal disease Liver disease Uncontrolled hypertension Significant cognitive impairment and / or degenerative neurological condition History of substance abuse Taking anticholinergic medication Known atherosclerotic disease Severe respiratory disease Known aneurysms Progressive neurological disorders Active cancer treatment
Outcome results
None listed