We want to provide you with some education on this important topic to make sure you stay warm at work as part of your winter safety plan. Appropriate warm clothing that maintains your body temperature in cold weather becomes more than just a suggestion or a choice; it truly is a necessity. 

Hypothermia is defined as a body temperature below 95°F (35°C).

Cold weather poses a threat even when temperatures seem mild. Hypothermia can set in when temperatures drop below 50°F, but many people do not know that or worry about their tingling in their fingers and toes until it’s much colder and too late. People work outside in cold temperatures gloveless, some with no jacket on, without even realizing that hypothermia can be a life-threatening condition that affects virtually every organ system in the body even at seemingly safe temperatures.

Each year, hundreds of people are killed from hypothermia in the United States and some years the numbers are in the thousands of people killed from hypothermia, even though it is completely preventable! Subnormal body temperature remains a leading, critical and preventable cause of injury and death.

Trench foot is another preventable condition that occurs at above-freezing temperatures and may go untreated because people are not even aware of it. Trench foot (immersion foot syndrome) is a serious condition resulting from your feet being wet for too long. Although trench foot is more common in temperatures of 30˚F to 40˚F, it can develop in desert climates because it results from having wet feet for prolonged periods. It causes damage to the circulation and nerve function of the foot.

With extreme cold hitting the Northeast and Midwest this week and winter even taking over the Southern USA, more outdoor workers, such as tow truck drivers, car haulers, accident recovery drivers, emergency response workers, and highway workers, will be at risk.

Many cities don’t declare a hypothermia alert until it hits 40°F, 20°F, or so cold as 13°F with wind chill when it is already very dangerous because that is after it is already at freezing. Even when it is not bitter cold outside, hypothermia occurs.

Hypothermia Stats

During the twenty-year period from 1979-1998, hypothermia was the cause of death for approximately 700 people annually in the USA, with half of these deaths attributed to extremely cold weather. Mortality rates in accidental hypothermia have ranged from 30%-80%.

Other Factors

Other important contributing factors include wind speed, moisture, alcohol, drugs, and the duration of exposure to the cold. The worst case of hypothermia in Boston occurred on a sunny 55°F day after it rained and the temperature dropped quickly to 34°F in the evening. His body temperature fell to a shocking 59°F and he had to have a cardio-pulmonary bypass therapy at Massachusetts General Hospital.

Everyone working outside when the temperature is lower than 50°F should become familiar with the signs, symptoms, and treatments for hypothermia:

Mild Hypothermia [90°-95°F (32°-35°C)]

Mild Hypothermia Symptoms: Increased heart rate and respiratory rate, hyperventilation, difficulty walking, slurred speech, impaired judgment, pronounced shivering, and frequent urination due to the “cold diuresis.”

Mild Hypothermia Treatment: Remove wet clothes and then cover the person with blankets or other insulation to limit any more heat loss and allow the patient’s body to generate heat and increase the core body temperature. People with mild hypothermia should be able to generate heat through shivering.

Moderate Hypothermia [82°-90°F (28°-32°C)]

Moderate Hypothermia Symptoms: The pulse drops, breathing becomes shallow with a slowed respiratory rate, shivering stops, the reflexes are slowed, and the person can become very confused and disoriented. Paradoxical undressing may occur. Cardiac arrhythmias are common.

Moderate Hypothermia Treatment: If failing to respond to passive external rewarming, which is active external rewarming with warm blankets, warm (not hot) baths, or heating pads, here is a risk of “afterdrop” when both the extremities and the trunk are warmed together, the cold blood that pooled in the extremities returns to the central circulation and can cause a drop in the core temperature. At the same time extremities are warmed, blood flowing away from the core can cause a sudden drop in blood pressure and result in dangerous medical complications. That is why rewarming the trunk of the body should come before the arms and legs.

Severe Hypothermia [below 82°F (28°C)]

Severe Hypothermia Symptoms: Hypotension, slow pulse, pulmonary edema, coma, ventricular arrhythmias (including ventricular fibrillation). The heart can stop beating completely (asystole or “flat line” on the EKG).

Severe Hypothermia Treatment: Active internal rewarming including the head, neck, lungs, liver to pelvic areas with WARM, not hot, fluids, hemodialysis, and cardiopulmonary bypass. These techniques can be augmented with warm humidified oxygen, warm intravenous fluids, and bladder irrigation with warm saline.

For severe hypothermia and cardiac arrest, perform CPR immediately while an ambulance is on the way. Since the cold has a protective effect on the brain when it has an absence of oxygen, attempts at rewarming should wait until after arrival at the hospital. Remember that people with core temperatures as low as 57°F (14°C) have survived.

Also check out this easy-to-read infographic.

What is Hypothermia?

The body generates heat through the metabolism of food and water, muscles moving around, and certain chemical reactions. The body’s heat is lost primarily through the skin and lungs in four important ways:

malfunction. Then, electrolyte imbalance occurs with increased potassium in the bloodstream. The hypothalamus attempts to stimulate heat production through SHIVERING and by increasing catecholamine and adrenal activity. To minimize heat loss, blood flow to the peripheral tissues is reduced.

THE WATER INSIDE AND OUTSIDE YOUR CELLS BEGIN TO CRYSTALLIZE AND CELL DEATH RESULTS. That is what that burning, tingling feeling is in your fingers and toes. Your body is literally freezing you to death without you even realizing that is what is happening!

In a study of 85 consecutive patients with hypothermia at San Francisco General Hospital, underlying infection or sepsis was the primary cause in 33 cases (39%). Exposure accounted for only 9 cases. Almost half (49%) of these cases of hypothermia resulted in death.

Additionally, medical conditions can either cause or increase the risk of hypothermia, including: sepsis, hypoglycemia, neuromuscular disease, malnutrition, hypothyroidism, and adrenal insufficiency. Some medications hinder the body’s response to cold thereby increasing the risk of hypothermia. If you work in the cold, ask your doctor about your medications.

Alcohol is particularly dangerous because it not only alters the ability to feel the cold and impairs judgment, but alcohol also further causes the loss of heat.

YOUR BRAIN STOPS FUNCTIONING PROPERLY AND BAD JUDGEMENT OFTEN MEANS MAKING DANGEROUS DECISIONS THAT END UP WITH DEATH OR LOSS OF BODY PARTS.

Signs and Symptoms of Hypothermia

Mild hypothermia causes poor coordination and clumsiness, stiff joints and muscles, and confusion, stumbling and falling, poor judgment that may cause accidents, drownings, and falls that can result in death.

The area that is involved feels cold and numb and can become clumsy. With rewarming, the numbness gives way to a severe throbbing pain that can last for many weeks. Some patients also describe a sensation of an “electric shock” running through the affected area. The frostbitten area often develops sensory loss and an increased cold sensitivity, which can last for years. Arthritis and chronic neuropathic pain can occur after deep frostbite in an area.

What is Frostbite and How Does it Happen?

Frostbite, which is local tissue freezing, can occur with any degree of hypothermia. Frostbite is most common in adults from 30-50 years old, which is incidentally the same age range of tow truck drivers and accident recovery personnel. In extensive studies from the Scandinavian countries, frostbite has been associated with wet and improper clothing, wounds, infection, diabetes, smoking, or a history of previous hypothermia or frostbite.

“Frostnip” refers to cold-related tingling and numbness that is not associated with any tissue damage. The hands and feet are the most common sites (almost 90% of the time), followed by the ears, nose, cheeks, and penis.

The 3 processes of tissue injury that occur at the same time:

Tissue freezing - Accompanied by the formation of ice crystals that damage the cell membranes. Then, water leaks out of the cells leading to cellular dehydration and death.

Shortness of breath, low levels of oxygen in blood or arteries, circulation issues - Peripheral blood vessels constrict in response to the cold, depriving the tissue of oxygen leading to blood clotting, which further exacerbates tissue issues.

The release of inflammatory mediators as the body tries to fight for the person’s life, which deprives the tissue of even more oxygen causing platelet aggregation, exacerbating the clotting. The peak time for that to occur is during the rewarming process.

The goal of treatment is to reverse or limit each of these processes. Rewarming can stop the tissue from freezing and reverse the vasoconstriction, while medications can block the release of the inflammatory mediators.

Diagnosing Hypothermia

Early recognition is critical. A physical exam with hypothermia in mind, as well as lab tests, helps to diagnose it because moderate and severe hypothermia because patients can appear dead, comatose, or in rigor mortis. The rule is to assume that no one is dead “until warm and dead” with resuscitation efforts continuing until the body temperature reaches 90°-95°F (32°-35°C), to err on the positive side.

The American College of Surgeons categorizes frostbite by the degree of tissue injury. This determination cannot be made until after rewarming, and sometimes it may take up to two weeks before the extent of damage is known.

Treatment

The goal of treatment is to salvage tissue by reversing the effects of tissue freezing, hypoxia, and the release of inflammatory mediators. The affected area(s) will be warmed in water at 104°-108°F (40°-42°C). Mild antibacterials be added. The rewarming process can be very painful, especially if this is done too quickly. Narcotics should be used for pain control as needed. Rewarming is complete when the skin becomes pliable and has a reddish-purple color. Afterward, continued immediate treatment is crucial to minimize tissue damage. Unfortunately, many present for frostbite medical care long after the initial damage and after the affected area has been warmed.

Prevent secondary infection and support the patient through a painful period of difficult medical decisions and great psychological stress.

In severe frostbite, any necrotic tissue forms in 9-15 days that is hard, black, and leathery over 22-45 days and the underlying tissue separates. Patients should be monitored carefully for wound infection drainage, which can be a sign of cellulitis or a deeper infection of the bone. Wound care and drying out the wounded area may offset blistering. Severe frostbite can cause a very painful nerve numbing, treated with medication.

Imaging techniques can accurately measure damage within 1-2 weeks after an injury, but fingers and toes with severe frostbite fall off in 3-6 weeks while the patient and doctors are helpless to do anything to prevent it from happening.

Possible complications from frostbite could be residual pain, cold and heat intolerance, increased sweating, thinning of the skin, and pigment changes.

Hypothermia Prevention

The best treatment of both frostbite and hypothermia is prevention. Wear a  hat and gloves in the cold, as well as layered warm clothing, and dry socks. Remember that frostbite occurs much more rapidly on windy and wet days. We have created a collection to help prevent these cold weather injuries. 

View cold weather apparel and hats that can help you be warm, seen, and safe this winter:

Winter Apparel | https://parts.ectts.com/winter-apparel-campaign

GSS Knit Hat | Lime/Black (ectts.com) | https://parts.ectts.com/hi-vis-fleece-hat-lime-bl... hat

Immediate Steps to Offset Hypothermia:

• 1.Call 911 immediately.
• 2.Remove wet clothing.
• 3.Put on a warm hat. 
• 4.Rewarm the right ways.

PLEASE SHARE THIS ARTICLE TO HELP SAVE A LIFE THIS WINTER!

Check out this easy-to-read infographic >>

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References

• 1.https://www.nhchc.org/…/diseases-and…/cold-related-injuries
• 2.http://nationalhomeless.org/tag/hypothermia
• 3.https://www.bhchp.org/…/BHCHPManual/pdf_files/Part2_PDF/Hyperthermia.pdf
• 4.American College of Surgeons, Committee on Trauma. Advanced Trauma Life Support. Chicago, IL: American
• 5.College of Surgeons; 1997.
• 6.Centers for Disease Control and Prevention. Hypothermia-related deaths - Philadelphia, 2001, and United States,
• 7.1999. MMWR 2003;52(5):86.
• 8.Heggers JP, McCauley RL, Phillips LG. Cold-induced injury: frostbite. In: Herndon DN, ed. Total Burn Care.
• 9.Philadelphia: WB Saunders; 1996:408.
• 10.Mechem CC. Accidental hypothermia. UpToDate, 2004. http://www.uptodate.com
• 11.Morris DL, Chambers HF, Morris MG, Sande MA. Hemodynamic characteristics of patients with hypothermia due to occult infection and other causes. Annals of Internal Medicine 1985;102:153-157.
• 12.Trench Foot: Symptoms, Causes, Pictures, and Treatment (healthline.com)
• 13.Trench foot - Wikipedia
• 14.Cold Related Illnesses | NIOSH |CDC