As temperatures dip into the teens and lower across the US this week, health experts are issuing safety warnings that could save lives.

An arctic blast is bringing the season's coldest temperatures to the Northeast and Midwest this week. Cities in New York are expected to see single-digit temperatures, while a dramatic swing in Chicago will plunge temperatures below zero. 

According to the forecasts, the regions could see temperatures as cold as -39F over the weekend, and parts could experience snow, making the cold temperatures even more dangerous.

With such arctic conditions, there is risk of an influx of people going to emergency departments for hypothermia, a dangerous drop in body temperature caused by prolonged exposure to cold. Between 15,000 and 19,000 people visit the ED every year due to hypothermia, while an estimated 700 to 1,500 people die from it.

Dr Alina Mitina, an emergency room physician at Hackensack University Medical Center in New Jersey, told the Daily Mail: 'In the ER, we see many cases of hypothermia and frostbite that were entirely preventable. We frequently treat individuals who went out for "just a few minutes" without proper gear. 

'This includes people walking their dog, going for a short walk or having their car break down. They are often dressed for a quick trip, not for prolonged exposure and are caught off guard.' 

In 20-degree air, initial shivering and numb fingers can begin within 10 to 15 minutes, but sweating or getting wet drastically accelerates the danger, as water pulls heat from the body 25 times faster than air.

Under those conditions, severe hypothermia can set in within 30 minutes, quickly progressing to violent shivering, confusion and loss of judgment within an hour. 

However, in the most extreme temperatures, even with a jacket, hypothermia can set in within just minutes of exposure.  

Mitina added: 'For a properly dressed and healthy adult, exposure should be limited as much as possible. Taking breaks in a warm place every 20 to 30 minutes is good practice. For vulnerable individuals, or if you are not adequately dressed, you could be in danger in as little as 10 to 15 minutes.' 

Beyond causing hypothermia and severe frostbite, frigid temperatures strain the heart and lungs by constricting blood vessels and raising blood pressure. As the body struggles to stay warm, its energy reserves deplete. 

Once core temperature drops below 95F (35C), mental functions like judgment and reasoning begin to fail. This risk is especially acute for the elderly, infants and those with pre-existing conditions like COPD or heart disease. 

While some people can spend the majority of their day indoors enveloped by heat, others, like delivery drivers, postal workers and even people taking their dogs on a brief walk, are at risk of potentially deadly effects of cold exposure.

Layering is key to protecting against the severe cold.  

Mitina said: 'Your first line of defense is proper clothing. Layer up with several layers of loose-fitting clothing with the inner layer moisture-wicking fabric like wool or silk to draw sweat away from your skin. 

'Avoid cotton, which holds moisture and will make you colder. Wet clothing chills the body very quickly. If you start to sweat or experience shivering, remove a layer of clothing to prevent getting damp.' 

She added: 'Protect your head with a warm hat, as a significant amount of body heat is lost through your head. For your hands, mittens are typically warmer than gloves. Wear waterproof boots to keep your feet dry and a scarf or mask to cover your face and mouth, which also helps protect your lungs.' 

Experts recommend limiting time outside as much as possible and avoiding alcohol. It may provide a warm, fuzzy feeling at first, but alcohol accelerates heat loss.

Finally, listen to the body. Uncontrollable shivering, confusion or numbness are not just discomforts but SOS signals to get inside immediately.

Mitina said: 'Shivering is the first sign that your body is losing heat and should be taken as a signal to get indoors. If possible, take frequent breaks in a warm location to allow your body to recover.'

Each system of the body is affected by the cold – the heart, the brain and all vital organs. The kidneys, liver and nervous system are critically dependent on a narrow temperature range.

Blood vessels in the skin, arms, and legs constrict severely when body temperature falls below 95 degrees, with an ideal of 98.6. This reduces blood flow to the periphery, minimizing heat loss but making fingers, toes, ears and nose vulnerable to frostbite.

As core temperature falls, the heart’s electrical system falters and heart rate slows as it becomes less efficient. 

The brain cools and metabolic processes slow down. Fine motor skills tend to fail first, followed by gross motor skills, leading to clumsiness and poor coordination.

Brain activity continues to decline with prolonged exposure to cold, causing people to fall into a stupor and eventually lose key reflexes such as the gag reflex. 

In severe hypothermic cases, confused victims may undress because malfunctioning nerves and the brain create a sensation of overheating as blood rushes to the dying skin.

Reduced blood flow to the kidneys leads to acute injury, disrupting fluid and electrolyte balance, while metabolism slows to a crawl, making the liver less efficient at clearing toxins.

In cases of severe hypothermia, the heart can stop, along with breathing.

Mitina said: 'Many patients tell us they were shivering for a long time but tried to "tough it out." Shivering is your body's alarm system. Ignoring it can lead to a state where you become confused and are no longer able to help yourself.

'We see tragic cases involving the elderly, who can develop hypothermia even indoors in a poorly heated home, and individuals experiencing homelessness.' 

While not directly causing vital organ failure, frostbite can lead to gangrene, a severe infection and the release of harmful substances into the bloodstream if tissues die and thaw.

She added: 'Listen to your body and monitor for signs of hypothermia and frostbite. Shivering is the first sign that your body is losing heat and should be taken as a signal to get indoors. If possible, take frequent breaks in a warm location to allow your body to recover. 

'With frostbite, the first sign is numbness or tingling of the area, which may feel like a pins and needles sensation. That is your sign to put on some warm mittens or use hand warmers.' 

When someone arrives at the emergency department with hypothermia, the core goal is gentle rewarming to safely raise the body's core temperature. 

A patient will be immediately moved to a warm room, have cold, wet clothing carefully removed and be wrapped in heated blankets. 

For severe cases, warmed IV fluids and humidified oxygen are administered, while the fragile, cold heart is carefully monitored.

For frostbite, treatment focuses on rapid, controlled thawing in a warm water bath, a process that requires strong pain relief with medication. Once thawed, the area is protected, elevated and dressed. Antibiotics and a tetanus shot are then given to prevent infection in the vulnerable, damaged tissue.