Circulatory Collapse, Circulatory Failure, Syncope, Vasovagal, Neurally-Mediated, Orthostatic Hypotension
Conditions
Brief summary
Suspension syndrome refers to a potentially life-threatening condition that can occur in unconscious persons after prolonged suspension in a harness. To date, our understanding of the pathophysiology and appropriate treatment is based primarily on case reports and expert opinion. The main pathophysiological hypothesis implicates blood pooling in the lower extremity and lack of return via muscle pumping. However, a recent French study could not support this hypothesis. Other mechanisms, such as a central vagal reflex may play a role in the pathophysiology of suspension syndrome. The aim of this study is to better understand the pathophysiological basis of suspension syndrome and to develop practical recommendations for prevention and treatment.
Interventions
OTHERSuspension in a harness
OTHERClimbing
Sponsors
Institute of Mountain Emergency Medicine
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy volunteers * Age 18-50 years * ASA class 1 * Signed informed consent
Exclusion criteria
* Age \<18 or \>50 years * ASA class \>1 * Informed consent not signed
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Heart rate | Change from baseline (measurement at minute 0) -> suspension phase (minute 10, timepoint immediately before interruption of suspension phase [max 60 minutes]) -> minute 5 and minute 15 after suspension phase |
| Blood pressure | Change from baseline (measurement at minute 0) -> suspension phase (minute 10, timepoint immediately before interruption of suspension phase [max 60 minutes]) -> minute 5 and minute 15 after suspension phase |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in maximal Diameter of superficial femoral vein | Change from baseline (measurement at minute 0) -> suspension phase (minute 10, timepoint immediately before interruption of suspension phase [max 60 minutes]) -> minute 5 and minute 15 after suspension phase | Ultrasound measurement of the Diameter of the superficial femoral vein in millimeters |
| Change in interbeat-interval | Change from baseline (measurement at minute 0) -> suspension phase (minute 10, timepoint immediately before interruption of suspension phase [max 60 minutes]) -> minute 5 and minute 15 after suspension phase | electrocardiographic measurement of interbeat interval in milliseconds (ms) |
Outcome results
None listed