Leadership

Tiffany Lipsey: Promoting Work-Ready Status on the Fireground through Effective Rehabilitation

BY TIFFANY LIPSEY

The focus on fireground rehabilitation highlights the importance of continued work readiness. In truth, work readiness can be extended with appropriate preparation prior to arrival on the fireground.  This article overviews the physiological and psychological function related to work and recovery in the fire environment and strategies for effective rehabilitation on the fireground.

Importance of Fireground Rehabilitation

Injuries and fatalities in the fire service occur when firefighters are about to fight fire, are fighting fire, or have just fought fire.  Fireground rehabilitation impacts two of those events.  Over the past 10 years, the leading cause of firefighter fatalities has been overexertion/stress/medical with the leading nature of fatalities as sudden cardiac death (SCD).  SCD is caused by a disruption of the heart rhythm.  By its nature, SCD does not typically have warning signs, which makes it difficult to identify those at risk.  One strategy is to look at the risk factors for SCD, which include the following:

·         Previous heart attack. The majority of SCD cases have a history of a heart attack with a large area of heart damage.  One statistic that is not known is the number of survived heart attacks in the fire service.  A person’s risk of SCD is greater within the first six months of a heart attack.

·         Coronary artery disease. Again, the majority of SCD cases have a history of coronary artery disease, which includes heart attack.  Coronary artery disease also encompasses those who have had stent or angioplasty and individuals with some other documentation of coronary disease such as a high coronary calcium score.

·         Risk factors for coronary artery disease. Risk factors include smoking, obesity, diabetes, family history of heart disease or sudden cardiac arrest, and high cholesterol.

·         Other heart related issues. There are several other factors that increase risk for SCD including heart rhythm, blood pressure, electrolyte abnormalities (specifically changes in magnesium and potassium), and history of syncope.

As part of my job, I work with Colorado firefighters assessing coronary artery disease risk factors and developing strategies to reduce risk for heart disease including SCD.  Not surprisingly, healthy firefighters perform better.  One of the best ways to be effective on the fireground is to be healthy and physically fit.  Firefighters face a challenging work environment and need every advantage.  Multiple factors affect performance in the heat.  These areas include equipment, environment, and physiology.

Physiological and Psychological Function Related to Work and Recovery in the Fire Environment

The neuromuscular, cardiovascular, pulmonary, and metabolic systems contribute to the body’s function. Physical fitness affects all of these systems and may be assessed by measuring local and general endurance, strength, speed, and power.  Many of these factors are assessed as part of the National Fire Protection Association (NFPA) 1582, Standard on Comprehensive Occupational Medical Program for Fire Departments, and the Wellness Fitness Initiative. Injuries and fatigue affect physical fitness and vice versa.  They also affect the safety of the firefighter and the crew.  Therefore, preventing both injury and fatigue are important.

To examine how the work in hot environments affects the body, there are three areas of focus:  equipment, work, and environment.  The gear (personal protective equipment or PPE) is bulky, heavy, thick and multilayered by design for protection.  These properties create challenges to the body.  The PPE inhibits water permeability, which decreases the body’s ability to evaporate heat and cool itself by trapping heat within the PPE.  Inside the PPE, the temperature of the skin during a fire ranges from 39˚C to 45.5˚C (102.2F to 113.9˚F), and the humidity reaches nearly 100 percent. PPE also increases the bulk and mass of the person, which changes gait mechanics and efficiency of movement. This does two things.  First, it makes firefighters walk differently with their gear on; second, it adds to the body’s heat production because the body has to work harder. Putting this into perspective, the average PPE weighs 24 kg (or ~53 pounds.  This decreases performance by 25 percent just by adding the weight to the body.  (Now, think about what extra pounds of body weight do to work.) By changing the gait mechanics, the cost of work increases by up to 50 percent.  Thus, there is a definite interest in developing lighter, less bulky gear that allows better range of motion. While protective, the currently available PPE yields a heat gain from the environment both by not allowing evaporation of heat and by increasing the energy needed to do the work.  PPE may add 10˚F to the heat index.

Work causes the body to generate heat internally. This heat must be dissipated. The core temperature will increase before the heat is transmitted to the skin, heating from the inside out. Typical firefighting work generates 300 to 500 watts of heat in the body. This heat needs to escape the microclimate, which is the space between the skin and the outer clothing. The body has four possible techniques for cooling:  evaporation, convection, conduction, and radiation. Because of the nature of the microclimate, convection, conduction, and radiation do not work.  Evaporation, which includes sweat and exhaled moisture, is the only possible cooling mechanism left. At best, the body can cool ~200 watts with evaporation. Recall that the work of firefighting is 300 to 500 watts. This leaves ~100 to 300 watts of heat gain. Thus, the body is always behind in cooling, and this is without considering the external heat gain from the environment, which, in this case, is the fire.

Most domestic fires are 40 kilowatts per meter squared (kW/m2); large fuelled fires are over 200 kW/m2.  The body’s cooling mechanisms are unable to overcome that heat gain and body temperature rise.  Despite this challenge, the body still tries to meet the cooling needs by increasing sweat production, which leads to dehydration.  If sweat rates decrease as an individual becomes dehydrated, this loss of body fluid limits the body’s ability to regulate body temperature. This is true regardless of the individual’s fitness level.

Firefighting Work and SCD

Denise Smith, Ph.D., proposed mechanisms that connect dehydration, increased body temperature, and adrenaline (epinephrine) with sudden cardiac events. These sudden cardiac events arise from arrhythmias, clot formation, plaque disruption, and circulatory shock.   

Hydration Status Factors

Dehydration leads to heat illness including heat shock and heat stroke.  There are several risk factors that firefighters may have as part of the environment, gear and their own physiology. Prolonged sun exposure is often encountered on fire scenes and is a risk factor for heat illness. Wearing heavy or excessive clothing, although necessary on the fireground, is also a risk factor for heat illness. Physiological factors that lead to heat illness include dehydration, obesity, low fitness level, caffeine consumption, cardiovascular disease, and medications.

Common blood pressure medications that impair thermoregulation (control of body temperature) include diuretics and beta-blockers. These are mentioned in NFPA 1582. Anticholinergic medications also impair thermoregulation by reducing sweat production. These medications are used to treat gastrointestinal disorders, genitourinary disorders such as prostatitis, and respiratory disorders like asthma and dizziness. Antipsychotic and antiemetic medications such as phenothiazines and butyrophenones impair thermoregulation. Consumption of alcohol will also impair thermoregulation.

Some substances increase metabolic heat production including some antipsychotics (benzotropine and trifluoperazine), ephedra-containing dietary supplements, diet pills, energy drinks, and methamephetamines. Individuals who have taken these substances will dehydrate more quickly because their metabolic heat production is higher than normal.

Determination of Hydration Level

Hydration level may be measured in several ways. An easy way to determine hydration is the color of the urine. Many departments have urine color charts posted in the bathrooms to aid firefighters in maintaining their hydration levels. The amount of dehydration may be measured by body weight loss. Although most fire departments do not typically measure body weight loss as part of rehabilitation on the fire scene, this may be helpful to include pre- and post-weights during a training exercise. This will allow firefighters to become familiar with their own weight loss and develop appropriate fluid-replenishment rates.

Psychological and Physiological Impacts of Dehydration

When using body weight loss caused by dehydration, there are decrements in psychological and physiological performance.  At 1 percent body weight loss, the heat transfer to the skin from the contracting muscles is decreased, limiting the ability of the body to remove internal heat. When the body weight loss from dehydration reaches 1-2 percent, heart rate increases and blood pressure decreases.  These are important parameters to monitor in the rehabilitation setting. NFPA 1584 dictates that knowing baseline values for these parameters is the responsibility of the firefighter. However, it is vital to realize that a low or “normal” blood pressure is not necessarily a good one.  Most guidelines that limit exit from the rehabilitation area are written to restrict activity if blood pressure is too high, not too low.  This is tricky because every individual has his/her own “normal.”  Baseline is not the measure taken at the entrance into rehab. As an example, if firefighter A has a post-rehabilitation blood pressure of 110/70, is he approved for more firefighting activities? At first look, most people would approve him to return to work, because this seems like a great blood pressure. However, what if his normal baseline is 150/80? If that is the case, firefighter A has probably lost 1-2 percent body weight and is on the dehydration path. He needs to remain in rehab until his blood pressure is closer to his normal. To put this in perspective, if firefighter A weighs 200 pounds, this is a two- to four-pound body weight loss.

When body weight loss is 2-3 percent, muscular endurance and energy level decrease.  That means that the ability of the muscles to perform tasks over a long period of time is less. Consider how long firefighters are on the fire scene. Most fire scene times are hours in length. Now think about what types of activities firefighters do on scene and into mop-up. These activities are continuous and last the entire scene time. With body weight loss ranging from 1-3 percent, the psychological decrements include increased decision time and a decrease in work memory. That means that firefighters will take a longer time to select their next actions, which may be at the cost of safety. This also means that firefighters may not remember what they did. Did they turn a valve off?  When they entered the structure and proceeded down a hallway, did they go right or left? What size hose line did they pull?

The psychological decrements worsen at 3-5 percent body weight loss.  The ability concentrate and focus are negatively affected.  Basically, when individuals are dehydrated, they cannot make good decisions because the factors that influence decision making are affected.  It is important to understand that focus and concentration are different. Focus is the ability to determine reality based on facts, not on feelings. Concentration is the ability to isolate attention to one task.  Both of these skills are essential in firefighting activities.

A major focus of reducing injuries and fatalities is looking for the “break in the chain” of events. What one event or series of events led to an injury or fatality? To reduce injuries and fatalities, many departments implement training strategies to reinforce good practices. All the training in the world will not help if firefighters do not remember what they did, lack the ability to determine the reality of situations, or are unable to concentrate on tasks. In review after review of firefighter injuries and fatalities, questions arise regarding firefighter decisions. It is plausible that they are making poor decisions because they are dehydrated and that dehydration has led to psychological decrements.

Thermoregulation (Body Temperature Regulation)

There are several mechanisms involved in thermoregulation. Some of these mechanisms involve ways to measure temperature and to aid in the maintenance of the temperature. The brain is key to measure and regulate temperature. To determine temperature, the brain “listens” to the skin warm receptors and the blood temperature to determine the overall body temperature. It promotes voluntary responses to cool the body such as drinking cool fluids, loosening clothing, fanning to facilitate air movement and aid in evaporative cooling, and initiating rest. The brain also signals the metabolic rate to slow to reduce heat production and the skin to vasodilate and sweat glands to activate to aid in heat transfer. Remember that while fighting a fire, firefighters are producing heat because they are performing work.  At the same time, the body is trying to stop heat generation.

There are several strategies to assist the body in cooling itself. The most inexpensive method of cooling is to simply remove the gear.  This allows only passive cooling, but it is better than nothing. However, studies demonstrate that passive cooling is not adequate to cool firefighters; active cooling methods must be employed.

Implementation of active cooling methods on the fireground present opportunities for creative problem solving. Active cooling methods include wet towels, misting fans, cooling vests, hand and forearm cooling, and tub immersion. One of the most practical methods utilizes wet towels. These towels are kept in ice water and then are placed on areas of the body that have an abundant heat supply, which are the same as those where ice packs are placed for heat emergencies. This method has several advantages: It requires little space; it has a short preparation time, and it is inexpensive. To address the infection-control issues of this method, use a three-bucket system. Bucket #1 is for the ice water.  Towels are kept there, so they are ready to use. Bucket #2 contains a color-safe bleach solution. This cleans the towels and keeps clothing from damage by regular bleach. Bucket #3 is a water rinse.  Firefighters take the cold towels from Bucket #1, cool themselves by wiping any exposed skin and placing the towels over the neck, head, and face as desired.  Used towels go into Bucket #2 to be cleaned and then are rinsed in Bucket #3.  Now they are ready to be returned to Bucket #1 to be used again.

Misting fans appear to work best in areas with humidity levels less than 70 percent.  They aid in cooling by promoting air movement and moisture to assist in evaporative cooling. Fans require an electrical source, and mold can be an issue.  While professional athletes use misting fans, their practicality for use on fire scene is debatable.

Tub immersion is another method used by athletes and works by conductive cooling. Large tubs, like those used to water livestock, are filled with water and ice to achieve a temperature of 10˚C-15.6˚C (50˚F-60˚F). Use in firefighting is impractical because the majority of the body needs submersion for the method to work, and the tubs are large; they must be transported, and it takes several people to move them. Infection control is also an issue.

There are several cooling shirts and vests available. Cooling apparel allows for the application of cool to the skin and works by promoting conductive cooling. By its design, it does not promote evaporative cooling. At times, the apparel may not fit correctly, and the loss of contact with the skin decreases the effectiveness of the garment. Cooling apparel is expensive and to accommodate multiple users, multiple shirts or vests will need to be purchased. Practicality for use in firefighting is also questionable because of the issue of when the garment should be worn and where firefighters will change into them.

Hand and forearm cooling involves placing the hand and forearm into cold iced water; the methods works by conductive cooling. Specifically cooling this area of the body works well because the hand has a high rate of heat exchange.  This high heat exchange rate arises from the large surface-to-mass ratio, low metabolic production, large blood supply, and rapid cooling rate.  Blood vessels in the hand are very sensitive to changes in the environment and in core temperature. This method also works quickly. The majority (70 percent) of the total heat loss occurs in the first 10 minutes of immersion. This method of cooling creates challenges for infection control and preparation.

Hydration Guidelines

Proper hydration supports sweat rates to promote cooling through evaporative mechanisms. With appropriate hydration, core temperature and heart rate decrease. It also preserves blood volume, which assists in heat transfer and helps to maintain electrolyte levels. Imbalanced electrolyte levels may lead to cardiac arrhythmias. This is one of the possible pathways to sudden cardiac death.

Euhydration is the state of adequate hydration with normal plasma electrolyte levels. This is the goal for optimal function. It is impractical to routinely measure plasma electrolyte levels. Proper hydration remains a formidable task.  NFPA 1582 suggests 32 ounces of fluid be consumed two hours prior to the event. Acknowledging that in emergency situations the time of the event is unknown beforehand, the maintenance of euhydration is challenging.

Take a look at the guidelines for performance athletes. The starting level used for athletes is approximately 5-7 mL/kg (0.077-0.11 ounces/pound) at least four hours before the event. For a 200-pound person, this is 15-21.5 ounces. This rate of intake may be easier to attain on a continual basis compared to the NFPA 1584 recommendation.

During the activity, NFPA 1584 indicates rehydration of at least 8 ounces for every two bottles or two work cycles. Compare this suggestion to the guideline for athletes, which is to rehydrate to less than 2 percent body weight loss from baseline.  This may be possible for firefighters if they have an idea of their body weight loss during firefighting activity. Consider measuring body weights at the next training exercise to have an idea of body weight loss. Some people sweat a lot, so they lose more weight. They need to replenish that loss. Establishing a general rate for each individual will aid in proper rehydration. The inability to effectively replenish fluid is a common problem. Most athletes do not consume enough during exercise to balance fluid loss; this includes Olympic athletes!

Ingestion of carbohydrate-electrolyte beverages during activity may delay the onset of dehydration and spare muscle fuel. It is imperative to note that inclusion of carbohydrate-electrolyte beverages will delay, but not prevent, dehydration. The advantages of carbohydrate-electrolyte beverages over water are the provision of a fuel source through carbohydrate and the replenishment of electrolytes lost through sweat. The addition of carbohydrate to this rehydration strategy may delay onset of fatigue, enhance performance, and increase work time to exhaustion. Effective carbohydrate-electrolyte beverages are marketed as sports drinks and typically are formulated to have 6-8 percent carbohydrate, which is 14 grams (1 teaspoon) of carbohydrate for every 240 mL (8 oz.).  To determine if a drink has the appropriate concentration, look at the food label. First, locate the amount per serving near the top of the label.  Typically, the serving size is 8 ounces, which is handy since that is the size in which the rate is given. The amount of carbohydrate is also listed on the food label. Look at the amount in grams, not the percentage. The percentage is based on percentage of daily value, not of the food item.

The addition of electrolytes in beverages helps drive the desire to drink, which aids in the mission of promoting adequate rehydration. Electrolytes may also help prevent cramping. The necessity for electrolytes is dependent on the composition of sweat, which is variable among individuals. The composition of sweat will also change with training levels and environmental exposure. It is not uncommon for the need for electrolytes to change based on these factors.

There are no guidelines for post-event rehydration in NFPA 1584.  However, there are post-event rehydration guidelines for athletes.  They suggest approximately 1.5 L (50 ounces) of fluid for every kilogram of body weight loss.  (This is 450-675 mL (23 ounces) of fluid for every pound of body weight loss. Again, notice the emphasis on body weight loss. For example, the 200-pound firefighter who loses 1-2 percent of body weight, which is 2-4 pounds, needs to drink 1.36-2.72 L (46-92 ounces).  That is a lot of fluid.

Rehabilitation on the Fireground

Firefighters need be ready at any given time. This presents challenges in how to approach this task. In athletes, the event day and time are known. They can train up to the event and then recover afterwards. Firefighters do not have that luxury.

NFPA 1584 provides a host of guidelines for fireground rehabilitation. A key factor in successful rehabilitation is to have a plan. The rehab plan needs to be adaptable to various emergency scenes. The following sections include some questions and suggestions for various aspects of rehab.

When is rehab activated?

There must be a guideline for when rehab is activated. Think about the public access automatic external defibrillator (AED).  What is the first action once you turn the AED on? Call for help now.  Use the same principle here.  Once you have established the type of call, determine if it will require rehab.

What type of rehab is needed?

Some scenes are intensive. Clearly, if it is a fire, you need rehab. That is easy. What about if there is an overturned tanker on the interstate that is not on fire, but you need to wait for hazmat to investigate? Does the standby crew need rehab? Some departments have two levels of rehab: light and full.

Light rehab is a set-up that will fit into the trunk of a car.  It includes some chairs, a tarp or tent, water, and snacks. The chairs provide a place to rest. They may be best placed in a location away from the public. The tarp may be used to provide shelter from the environment (sun, wind, precipitation). Water and snacks provide some fuel and rehydration. The snacks may be as simple as food bars, like nut bars or energy bars.

Light rehab is helpful when the workload is low, but the event is long. Firefighters are typically still wearing some of their PPE, which demands more work to be done by the body and inhibits effective cooling. This means that they are fuel depleted and dehydrated.

Full rehab is everything including the kitchen sink. The appropriate resources are essential to accomplish the tasks of rehab. Some departments have rehab buses that literally do have everything including the kitchen sink. The following is a list of items to consider for full rehab:

·         A med kit including regular and large adult blood pressure cuffs

·         Portable shelter (tarps or tents)  (May be used to designate areas or be used for shelter)

·         Blankets

·         Portable heaters

·         Dry clothing

·         Electrical generating equipment

·         Misting and cooling equipment such as fans or blowers

·         Lighting

·         Rehabilitation area designation marking equipment

·         Chairs

·         Beverage-serving equipment

·         Exposure protection garments for the rehab staff

·         Personnel washing equipment (basins, soap, water, and towels)

·         Cups (hot and cold according to beverage)

·         Potable water

·         A large clock

·         Traffic cones

·         Fireline tape

·         Log book, forms, and writing implements

·         Sanitary facilities (portable toilets)

·         Food (including appropriate serving devices and equipment)

·         Trash and recycling receptacles

Please note that of the above list the only item that is not listed in NFPA 1584 is the med kit. The med kit is essential to assess vital signs. Appropriately sized blood pressure cuffs aid in proper readings.

Sanitary facilities are necessary. This provides the firefighters with a private location to take care of relieving themselves of any excess fluid they have, which, if they are appropriately hydrating, should be the case.  Some firefighters choose not to drink fluids because they have nowhere to go to the bathroom. The sanitary location also keeps the public happy because they do not observe firefighters going into the bushes to relieve themselves.

What are some food considerations?

It is important that the person in charge of rehab be familiar with any food allergies the firefighters may have and stock food options that accommodate these allergies.  Some common food allergies include nuts, dairy, and gluten.

Beware of hidden stimulants in prepackaged foods. They will increase metabolic rate and heat production.

Unfortunately, the most common foods served in rehab, pizza and sandwiches, are not optimal. They are often easily acquired, but they have high fat and high carbohydrate content.

Consider foods that are easily portable.  This makes it easier on the personnel responsible for rehab. In addition, the food choices should be low in sugar and high in protein. Remember that “low in sugar” does not mean no sugar. Carbohydrates are sugars at their base. They provide quick fuel, which is typically used within 20 minutes. Providing foods with some fat and high protein allows the body to have fuel sources that last longer.

What about the time of day?

An important consideration in the need for rehab is the time of day. If there is a fire at 0200 hours, when is the last time the firefighters ate?  What fuel are they running on if they last ate at 1800 hours?

In most communities, acquiring food at night/early morning hours is challenging.  Do some investigation into how late restaurants are open in your community. If restaurants are not an option, develop a store of food staples that works well for rehab.

Where is a good location for rehab?

Scenes are often challenging because of their locations.  Rehab should be close to staging if possible. The rehab location should not be facing the incident. Blood pressures and heart rates of firefighters will return to baseline better when firefighters have a break from the continual stimulus of the scene. In addition, a location out of view of the paparazzi and the public is ideal. This provides the firefighters with a safe environment to debrief and deal emotionally with the incident before having to re-enter firefighting activities. With the ease of taking photos with a phone and social media, the additional consideration to protect firefighters from these assaults may protect the firefighter and the department.  Environmental protection is helpful. Protect the firefighters from wind, direct sunlight, and precipitation if possible.

What are some other considerations for rehab setup?

Provide a place for firefighter equipment. This will help the gear to remain secure.  Some rehab setups provide hooks to hang gear. This keeps the gear off the ground, which may be muddy or dusty. If the coat is inverted, it will have a chance to dry.

Provide a means to wash the face and hands. Some departments provide baby wipes for this task.

What if your scene changes?

Fire scenes may be unpredictable. Have a plan for expandable rehab if the fire grows and requires more personnel. Explore resources and strategies before the fire scene demands it.

Rehabilitation and Medical Evaluation

It is vital to understand that rehabilitation and medical evaluation are different.  Many departments will perform both of these functions in the same space.  Rehabilitation is the first step. The function of rehab is to extend work times and to ensure firefighters are safe to return to work. Medical evaluation is for extended efforts, environmental challenges, and at-risk personnel.

The culture of the fire department can sometimes be problematic. Medical authority is one of the challenging areas. Personnel must understand that emergency medical services providers have the authority in the rehab sector through the incident commander. Privacy of the individuals must be maintained.

There are three important areas that need specific guidelines:

1.      Who needs immediate treatment?

2.      Who needs closer observation?

3.      Who can leave rehab and return to work?

Concerning the above three questions, develop guidelines that include observable signs and focus on the safety of the firefighters.

Rehabilitation Data

The data collected in rehab include heart rates, blood pressures, and respiratory rates. Each department needs a policy on who “owns” these data and what happens to them.  Identify a location for storing these records. Rules for accessing the data need to be established.

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To have effective rehabilitation on the fireground is a process. It is more than just supplying some water and energy bars. Creating a plan for rehabilitation and implementation of that plan are worth the effort to have firefighters that operate safely and more effectively.

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BIO

TIFFANY LIPSEY is the assistant director of the Human Performance Clinical/Research Laboratory and an assistant professor in the Department of Health and Exercise Science at Colorado State University. She has a master’s degree in kinesiology from the University of Virginia.  Her experience includes more than 20 years with the emergency services.