Rhabdomyolysis (often called rhabdo) is a serious medical condition that can be fatal or result in permanent disability. Rhabdo occurs when damaged muscle tissue releases its proteins and electrolytes into the blood. These substances can damage the heart and kidneys and cause permanent disability or even death. In the workplace, causes of rhabdo include heat exposure, physical exertion or overuse, and direct trauma (e.g., crush injury from a fall). Anyone can get rhabdo, but workers in many different occupations have a higher chance of developing rhabdo.

Early treatment can prevent serious medical problems and increase your chances of a quick recovery and return to work without any lasting negative health effects. Learn the signs and symptoms and get tested right away if you suspect rhabdo!

Rhabdo is the breakdown of damaged muscle which results in the release of muscle cell contents into the blood. The proteins and electrolytes released into the blood can cause organ damage. Workplace risk factors include heat exposure, physical exertion, and direct trauma (e.g., crush injury from a fall).

Potential Problems due to Rhabdo

Rhabdo can cause many problems, including:

• Kidney damage or kidney failure
• Dangerous heart rhythms (arrhythmias)
• Seizures
• Nausea and vomiting
• Permanent disability
• Death

Muscle damage can also cause a medical condition called compartment syndrome:

• A compartment is a group of muscles bound together by a thin, fibrous sheath or covering.
• Injury to a muscle inside the sheath can cause swelling. The pressure inside the sheath can rise since the sheath cannot stretch very far.
• High pressure inside the sheath can prevent blood from entering to feed the muscles inside.
• When muscles inside the compartment aren’t getting enough blood, they die. This is compartment syndrome.
• Compartment syndrome is not common, but it is important to get immediate medical treatment. Delayed treatment can cause permanent disability as the body cannot replace dead muscle.

Early recognition and treatment can prevent many of these problems!

Anyone can get rhabdo, but some workers are at a higher risk than others. People who work in hot environments and/or perform strenuous physical tasks have a higher chance of getting rhabdo. Some of these groups include:

• Firefighters (both structural and wildland)
• Police officers
• First responders
• People who work in hot environments, such as farm and construction workers or forge workers
• Military service members
• Athletes

Common causes of rhabdo in the workplace include:

High Body Temperature

People who work outdoors in hot environments, in or near hot processes (such as forge or smelter workers, roofers, and asphalt pavers), or who wear personal protective equipment that can trap in body heat (like the heavy coats and pants structural firefighters wear) have a higher likelihood of developing rhabdo

Overuse of Muscles

People who work physically demanding jobs that involve high levels of physical exertion or participate in high intensity workouts or physical fitness tests have a greater chance of developing rhabdo.

Physical Damage to Muscles

Any work that could potentially result in traumatic injuries (such as falls from heights or car accidents) puts workers at a higher risk for rhabdo.

Other things that can increase your chances of developing rhabdo include:

• Using illegal drugs, such as cocaine and methamphetamine
• Excessive alcohol consumption
• Taking supplements, such as creatine and ephedra
• Consuming large amounts of caffeine or other stimulants
• Different infections, including flu, HIV, salmonella, staph, strep, and Epstein-Barr virus (mono)
• Certain medical conditions, such as uncontrolled diabetes, sickle cell disease, thyroid disorders, and muscular dystrophy
• Some medications, including some antibiotics, antidepressants, cholesterol-lowering drugs (statins), and cold and allergy medicines

It’s important to learn the signs and symptoms of rhabdo that may be present. Learning the symptoms can help you figure out if you or someone else needs to seek medical attention. If you develop rhabdo, you might have one or more of these symptoms:

• Muscle cramps, aches, or pains that are more severe than expected
• Dark urine (tea- or cola-colored)
• Feeling weak or tired, unable to complete job tasks or finish a workout routine

It is possible to have rhabdo and show no symptoms. If you do begin to show these symptoms, seek medical care immediately!

When will symptoms appear?

The only way to know you have rhabdo is through a blood test that checks for the presence of a muscle protein, creatine kinase (CK), in the blood. If you suspect that you may have rhabdo, ask to have your CK levels checked.

Symptoms can appear any time after muscle injury. For some people, symptoms might not start to appear until several days after the initial injury. If you have any of these symptoms at any time, do not ignore them. Seek medical treatment right away. Earlier diagnosis means an earlier start to treatment and a greater chance of recovery without permanent health effects.

You can’t tell by symptoms alone if you have rhabdo. Other conditions like dehydration and heat cramps can cause the same symptoms. The only way to know for sure is to obtain a blood test.

Repeated blood tests for the muscle protein creatine kinase (CK or creatine phosphokinase [CPK]) are the only accurate test for rhabdo.

A healthcare provider can do a blood test for CK:

• The muscle protein CK enters the bloodstream when muscle tissue is damaged.
• When rhabdo is present, CK levels will rise.

You will need repeat blood tests to determine if CK levels are going up or down:

• Like symptoms, the rise in CK may not appear right away.
• Healthcare providers should test CK levels until 2 consecutive tests show levels lowering.

Urine dipstick tests are not a good way to diagnose rhabdo:

• These tests check for myoglobin (a muscle cell component) indirectly.
• Myoglobin quickly clears from the body so it may not show up in urine.
• High CK levels in the blood may persist for days.

If you suspect you have rhabdo and your healthcare provider does not check your serial CK levels, be sure to ask for it!

Seek treatment as soon as you suspect rhabdo! If treated early, most rhabdo patients return to work in a few days without any lasting effects. Treatment options depend on how severe the rhabdo is. Only a healthcare provider can determine how severe it is through blood tests, electrocardiograms (also known as EKGs), etc.

Less severe cases can be treated with:

• Drinking fluids
• Getting out of the heat
• Resting

Moderate to severe cases may need intravenous (IV) fluids and hospital admission.

• IV fluids help flush out the muscle proteins and electrolytes. IV fluids can prevent dangerous heart rhythms and loss of kidney function.
• At a hospital, medical professionals can monitor and treat severe cases for:
  • abnormal heart rhythms
  • decreased kidney function
  • seizures
  • elevated compartment pressures
  • high potassium levels

You can’t completely eliminate your risk for rhabdo, because we currently don’t know all of the risk factors. However, there are ways you can lower your risk.

• Be aware that job or recreational activities involving exertion and/or heat exposure could increase your risk for rhabdo and try to avoid these risk factors if possible.
• Learn the signs and symptoms of heat-related illnesses and take steps to prevent getting overheated. Take frequent rest breaks and use cooling stations if available.
• Become acclimatized to your physical activity level and the heat before working for long periods of time. Keep this in mind when returning to work from vacation or starting a new job in a different climate.
• Stay home from work when you’re sick. Many illnesses (such as the flu) and cold medications may increase your risk for rhabdo. Staying home when sick will also protect your coworkers from getting sick.
• Stay hydrated. Drink caffeine-free and low-sugar products. Avoid alcohol use when working in the heat.

If you start experiencing any rhabdo symptoms, stop your current activity right away, cool down, start drinking fluids, and go to a healthcare provider to get checked for rhabdo.

What can employers do to prevent rhabdo?

Employers can help protect their employees from developing rhabdo by implementing the policies and procedures listed below:

• Have a heat stress management policy to decrease risk of heat-related illness that could lead to rhabdo. Follow the guidelines presented in the NIOSH Heat Stress recommendations.
• Allow and encourage employees to seek medical care when they have rhabdo symptoms. Let employees know they can return to work once they are cleared by their doctor.
• Encourage employees to take sick leave when sick, as many illnesses increase the risk for rhabdo.

Rhabdomyolysis (rhabdo) is a medical condition associated with heat stress and prolonged physical exertion. Rhabdo causes the rapid breakdown, rupture, and death of muscle. When muscle tissue dies, electrolytes and large proteins are released into the bloodstream. This can cause irregular heart rhythms, seizures, and damage to the kidneys.

Symptoms

Symptoms of rhabdo include:

• Muscle cramps/pain
• Abnormally dark (tea or cola-colored) urine
• Weakness
• Exercise intolerance
• Asymptomatic

First Aid

Workers with symptoms of rhabdo should:

• Stop activity
• Drink more liquids (water preferred)
• Seek immediate care at the nearest medical facility.
• Ask to be checked for rhabdomyolysis (i.e., blood sample analyzed for creatine kinase).