Acute Effects Of Firefighting On Vascular Health And Blood Pressure

Abstract

Firefighting is strenuous and dangerous work. Sudden cardiac death accounts for approximately 50% of firefighter line of duty deaths. PURPOSE: To determine the vascular and hemodynamic responses firefighting work across different positional assignments. METHODS: 40 experienced male firefighters completed a coordinated fire attack in a wood frame residential structure. Responding personnel were classified based upon four separate positions (assignments), including: Outside Command, Outside Vent, Inside fire suppression and search and rescue, Overhaul. Subjects were equipped with an automated blood pressure and pulse wave analysis device for measurement of cardiovascular variables (Mean Arterial Pressure, Total Vascular Resistance, Cardiac Output, Stroke Volume, Pulse-Wave Velocity). Measurements were made before, immediately after, and 30 minutes after fire suppression activities in a single-story residential structure. RESULTS: Increased mean arterial pressure (MAP) measured prior to the exercise indicates an anticipatory rise in sympathetic activation across all positions (Table 1). Those performing Inside suppression/search and rescue exhibited the greatest increase in MAP across all groups, with MAP remaining elevated immediately following the training exercise and a return to baseline conditions occurring 30 minutes post training (Table 1). This group also exhibited the greatest excursion in systolic blood pressure in response to training (Pre: 130.7 ± 12.7, Post: 134.6 ± 17.3). CONCLUSIONS: The vascular changes evidenced during acute firefighting may play a mechanistic role in the increased risk of sudden cardiac death with firefighting. Additional research is needed to better understand how these changes are related to myocardial blood flow.Table 1: Data are expressed as Average (SD)