Since 1990 we've been unable to make a significant impact on firefighter line-of-duty deaths. Despite the efforts of the National Fire Academy, the IAFC and the IAFF, we still continue to lose a little more than 100 firefighters a year — a 10% rise in firefighter LODDs over the last 10 years.

We have seen the application and development of NFPA 1500, Fire Department Occupational Safety and Health Program, and NFPA 1582, Medical Requirements for Firefighters and Information for Fire Department Physicians, make little impact on reducing the numbers of casualties. We also have seen the USFA redefine its strategic mission to include a 25% reduction in firefighter fatalities in five years and a 50% reduction in 10 years, tailoring several of the NFA course objectives to support these goals.

While there are several studies accumulating numbers, little has been done to research the mechanics of the causes and what interventions we can employ to curtail line-of-duty fatalities. Heart attacks continue to be one of the major causes of firefighter fatalities, accounting for more than 44% of the deaths occurring on the fireground. Every year, approximately 40 LODDs are from heart attacks.

Firefighters between the ages of 41 and 45 have a 50% chance of a heart attack causing their death if they fall victim on the fireground. In most cases a person in their mid-40s with a fainting spell or shortness of breath would not always be evaluated for cardiac arrest, but the National Fire Academy's statistics show what appears to be underlying cardiac disease in firefighters at a fairly early age.

One major issue is the management of blood pressure among firefighters. Heart disease can be precipitated by uncontrolled fluctuations or sustained high blood pressure, a major contributor to heart attack. The management of blood pressure may be facilitating the increases in cardiovascular-related deaths. Typically, medication is used to control high blood pressure. The most popular method is beta blockers, which are designed to control blood pressure by keeping the heart rate low.

Consider the design of firefighter turnout gear and the vapor barrier technology that's designed to keep a firefighter cool. Much of that system is designed to pull heat from the body. The human body needs to respond to heat stress by elevating heart rate and dissipating the heat. Beta blockers work against that system and predispose firefighters to heat-related emergencies. Diuretics and calcium channel blockers have similar effects by working against the body's protective systems.

A more appropriate strategy may be the use of angiotensin-converting enzyme inhibitors, or ACE, to control blood pressure by causing dilation of blood vessels and dissipating heat more effectively. This enzyme inhibits a hormone called angiotensin in the body. Once activated, angiotensin causes blood vessels to constrict, resulting in high blood pressure and a strain on the heart. ACE inhibitors prevent the activation of angiotensin, resulting in dilated blood vessels and a lower blood pressure.

Even in firefighters with normal blood pressure, blocking the activation of angiotensin and dilating blood vessels is effective in a heat stress situation. ACE inhibitors aren't prescribed as often as other drugs because they're less profitable for pharmaceutical companies. Most are off-patent and cheaper than brand-name products of other types.

Most departments require supervisors to be notified when members are on medication that may affect operations. Three key points need to be gleaned from this information:

1. The fire department physician must understand how blood pressure medication affects firefighters in turnout clothing. Often this requires placing the department doctor in turnout and placing him or her in live-fire training to experience heat stress first hand. Fire department physicians should be familiar with NFPA 1582. It should be incumbent on the fire chief to ensure that the health and safety officer provides a copy of the document to the fire department physician.

2. Many of the cardiovascular deaths in the fire service are occurring in young people, and management of blood pressure may help reduce the number of deaths.

3. We need to get tough on the application of rehab procedure during firefighting screening for hypertension and ensure garments are removed and people are hydrated. As with all of this information, scientific studies and additional efforts to measure exactly what's most appropriate for managing hypertension among firefighters should be conducted. A significant amount of research is being completed on heat acclimation, and the next few years will yield new approaches to prepare firefighters for heat stress.

Another hidden problem is chronic exposure to carbon monoxide, which may be contributing to the cardiovascular disease deaths reported in the fire service. Not just an asphyxiant, carbon monoxide has delayed effects as indicated by new information that long-term exposure has a direct effect on heart muscle function.

Carbon monoxide can cause permanent damage to the heart and nervous system. In fact, the death of a 48-year-old firefighter in Emmett City, Idaho, in March is being linked to carbon monoxide. Using SCBA during overhaul operations and the consistent sampling of the atmospheres by command officers prior to allowing the removal of SCBA needs to become common practice.

In many cases the toxicology measurement is not fully assessed in a firefighter LODD. It's important to understand that we have the equipment to sample for carbon monoxide on the emergency scene. The technology also is available to directly sample it in a firefighter through a handheld spirometer device, traditionally used to sample carbon monoxide in smokers participating in smoking cessation programs. These units are affordable for EMS units to use in sampling actual carbon monoxide levels in firefighters while in the rehab phase of fireground operations. Every working fire should have an EMS unit at the scene on standby with at least an AED and ideally 12-lead EKG capabilities.

The NFA, IAFF and National Volunteer Fire Council need to put forth a national, collaborative effort to establish a long-term surveillance project that includes the incorporation of a standardized exposure report. Shockingly, in a 10-year evaluation of firefighters suffering fatal heart attacks in the line of duty, one third had never had a department-sponsored physical. The National Institute of Occupational Safety and Health should work to identify physiological factors that may be contributing to firefighter LODDs.

Firefighters are a stable population ideal for measuring long-term effects. When we make attempts to link cancer or heart disease to job-related issues, there's an incredible lack of definitive science. With the exceptions of Florida and Nevada, few states have presumptive legislation on cancer and heart disease for firefighters. These states have aggressive heart lung bills that should become a model for the rest of nation. To read the Florida Professional Firefighters summary of presumptive legislation for public safety workers, go to www.fpfp.org/content.cfm?s=view&CID=3&ID=13-. For a link to the Nevada Heart lung bill and sections that cover firefighter presumptive legislation, go to http://www.leg.state.nv.us/nrs/NRS-617.html#NRS617Sec455.

The fire service needs to partner with major research hospitals and aggressively look for direct cause-and-effect issues related to the death of firefighters. Cardiovascular disease will remain the leading cause of death until we employ our own fire prevention model to this problem and identify specific intervention strategies.

Bruce Evans is the fire science program coordinator at the Community College of Southern Nevada as well as an adjunct faculty member for the National Fire Academy's EMS and injury prevention courses. A captain at the Henderson (Nev.) Fire Department, he has a master's degree in public administration and an associate's degree in fire management.