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Published on: April 1, 2015
Clotting and fibrinolytic changes after firefighting activities
Denise L Smith1, Gavin P Horn, Steven J Petruzzello
11Illinois Fire Service Institute, University of Illinois Urbana-Champaign, Champaign, IL; 2Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY; 3Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL; 4Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL; and 5Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL.
Strenuous firefighting increases blood clotting and fibrinolysis. Two hours post-firefighting, clotting remains elevated, potentially linking firefighting to sudden cardiac events in firefighters.
Area of Science:
- Cardiovascular Physiology
- Hematology
- Occupational Health
Background:
- Sudden cardiovascular events cause 45-50% of firefighter line-of-duty deaths.
- These events disproportionately occur after strenuous fire suppression activities.
Purpose of the Study:
- To evaluate the impact of strenuous firefighting on platelet function, coagulation, and fibrinolysis.
- To assess the recovery of these hemostatic variables 2 hours after firefighting.
Main Methods:
- Firefighters engaged in 18 minutes of simulated firefighting with live fires.
- Blood samples were collected pre-firefighting, immediately post-firefighting, and 2 hours post-firefighting.
- Participants recovered for 2 hours with fluid intake after the activity.
Main Results:
- Platelet count, activity, and coagulatory potential increased immediately after firefighting.
- A procoagulatory state persisted 2 hours post-firefighting for several variables.
- Fibrinolytic activity (tissue plasminogen activator) returned to baseline by 2 hours, while inhibition of fibrinolysis (plasminogen activator inhibitor-1) decreased.
Conclusions:
- Firefighting significantly elevates both coagulatory and fibrinolytic activity.
- A procoagulatory state persists 2 hours post-firefighting, even as fibrinolytic activity normalizes.
- This sustained procoagulatory state may mechanistically explain sudden cardiac events in firefighters post-exertion.
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