By Todd LeDuc
The United States fire service continues to be plagued by the fact that a majority of on-duty deaths are sudden cardiac deaths. A significant portion of these occur on the fireground during fire operations, despite the fact that such a small amount of time is spent fighting fire during a firefighter’s shift.
This of course suggest the notion that the extreme rigors, heat, and stress of fireground operations must play a key role. Much research has been done in this area to better under that pathophysiology and manageable risk. A retrospective study published in 2018 in the Journal of the American Heart Association by Dr Denise Smith and colleagues found that on postmortem examination that 79.6 percent of sudden cardiac deaths in firefighters had underlying cardiac heart disease and cardiomegaly or left ventricular hypertrophy or an enlarged heart muscle.
A number of cardiac postmortem reviews in that same study had a coronary artery with greater than 50 percent blockage, a thrombus or clot within the coronary artery itself, or evidence of a prior heart attack. A number of contributory factors come into play, including a sympathetic nervous system response from the “fight or flight” mechanism our body is wired to respond with as we engage in stressful and strenuous activities.
This includes an increase in heart rate, respiration, blood pressure and oxygenation demand, heat stress, and dehydration. Additionally, blood and coagulatory changes play a role, with a decrease in circulating volume and increases in platelet numbers and function (clotting).
Read More: https://www.fireengineering.com/2020/10/16/495041/sudden-cardiovascular-death-and-disability-in-firefighters-a-complex-interplay/