03.06 Hypothermia (Thermoregulation)

Join NURSING.com to watch the full lesson now.

Included In This Lesson

Study Tools



  1. Hypothermia
    1. Body fails to sufficiently heat self
    2. Organ dysfunction

Nursing Points


  1. Hypothermia = body 95 degrees F or lower
  2. Causes by loss of heat
    1. Radiation ->through air
    2. Conduction ->direct contact
    3. Convection->fluid or gas movement
    4. Evaporation or respiration->heated water droplets
  3. Effects on body
    1. Slows ALL functions
    2. Hypothalamus tries to maintain homeostasis
      1. Conservation
        1. Vessels constrict
      2. Heat conduction
        1. Shivering
        2. Increased thyroxine
    3. Glycogen storage used to maintain processes (energy)
    4. Eventually homeostasis is overwhelmed and fails
      1. Glycogen depleted
      2. Core temperature drops
      3. Organ system failure


  1. Presentation
    1. Confusion
    2. Weak, irregular pulse
    3. Decreased respiratory rate
    4. Increased urine release
    5. Frostbite, numbness
  2. Vital signs
  3. Check neurological status
  4. Intake and output
  5. Skin assessment
  6. Check blood sugar (depleted glycogen)

Therapeutic Management

  1. Remove wet clothes
  2. Passive warming
    1. Blankets
    2. Warm room
  3. Active warming
    1. Forced warm air (warming device)
    2. Inhalation of warm humid oxygen
    3. Blood rewarming (dialysis)
  4. IV fluids
    1. Rehydrate and increase volume while rewarming

Nursing Concepts

  1. Thermoregulation -> body working to warm self
  2. Perfusion -> Everything slows, perfusion decreased as glygogen stores depleted
  3. Glucose metabolism -> Body switches to gluconeogenesis to use stored glycogen for energy

Patient Education

  1. Dress warm – layers
  2. Avoid immersion in cold water for long
  3. Prepare car in winter
  4. Don’t drink alcohol outside in cold weather


Hey guys! Welcome to the lesson on hypothermia. Let’s get started. 

So hypothermia is where the body cannot sufficiently warm itself. Normal body temperature is 98.9 degrees, but when the body’s temp drops below 95 degrees, the person may become hypothermic. The use of energy reserves ends up in organ dysfunction. Let’s get into what may cause hypothermia.

So hypothermia can happen from different ways of losing heat in the body. Radiation is the loss of heat through air, like if a patient has been outside in the cold winter for too long. Conduction is loss of heat from direct contact, like if that patient was lying in the cold snow without a coat and gloves. Convection occurs with fluid or gas movement, like if this patient decided to polar plunge into a cold river. Evaporation or respiration is the loss of heat through breathing for example. Now let’s explore what happens when the body gets too cold. 

So the low temperature causes all functions of the body to slow. The hypothalamus in the brain helps maintain temperature homeostasis in the body by conserving heat with vessel constriction. It also tells the body to conduct heat by shivering and increasing thyroxine which is a thyroid hormone that helps keep the body warm. All of this requires a lot of energy right? So the body is going to then have to resort to gluconeogenesis in the liver where the glycogen storage is used to maintain the body’s processes. Eventually homeostasis will become overwhelmed and fail. The glycogen will run out so the body will not be able to compensate anymore to make heat with the shivering and vessel constriction. The vessels will relax, shivering will stop, and the core body temperature is going to drop, and eventually the organ system will fail. So what’s this patient going to look like?

The lack of blood flow to the brain and the lack of glucose will result in confusion. The patient may have a weak, irregular pulse because remember the processes slow down and energy is being depleted. The respiratory rate will slow in attempt to reserve heat by slowing the loss of heat through the lungs. The constriction of vessels and severe cold will cause the body to diurese by increasing urine release. Ever notice how you have to pee more when your cold? This is why. Frostbite and numbness may occur from the excessive cold on fingers, toes, ears, or the nose from death of the tissue. Let’s talk about the patient assessment. 

So of course we want to check this patient’s vitals, and also their neurological status. If they were out in the cold, can they feel their fingers and toes? Check over their skin for any frostbite. Intake and output should be measured to assess for hydration. You should check the blood sugar because remember, hypothermia depletes the body’s energy sources, so it may be low. No how will we manage this?

So depending on the severity of the hypothermia, you may try passive warming or active warming. Passive warming is using blankets or having a warm room for less severe cases like a little old lady that has a low temperature of 95.6.  Active warming is for more severe cases like that patient that was outside in the cold winter lying in the snow all night. We may use a warming device that pushes warm water through a large heating pad to warm the patient. Oxygen may be threaded with warm humid air. In desperate situations, dialysis may be used to rewarm the blood. While rewarming this patient, hydration will have to be restored with IV fluids to avoid severe drops in the blood pressure. Remember, warmth makes the vessels dilate. Next let’s discuss what to teach the patient. 

So tell your patient about the importance of dressing warm and avoiding cold water. This seem silly, but this should especially be educated to the homeless and those that drink alcohol. Think of what alcohol does, it impairs cognition. They may not realize just how cold it is outside and act on risky behavior in the winter like jumping into an icy lake. It is helpful to also prepare cars in winter with blankets in case something happens where they are stuck for hours without help. The priority nursing concepts for the patient with hypothermia are thermoregulation, perfusion, and glucose metabolism. 

Okay, let’s review the key points. Hypothermia is where the body temperature drops below 95 degrees for an extended time. This affects the body by slowing the processes down because the body is trying to conserve energy. The body attempts to conduct heat by shivering and constricting vessels, which is super tiring on the the body so eventually the glucose runs out. The body then turns to gluconeogenesis in the liver to metabolize sugar from reserves for energy. This only works until reserves are exhausted, the body will then tire out completely and temperature homeostasis will fail. The vessels will relax allowing more cold in the body and everything will shut down. The cold affects the body through radiation through the air, conduction by touch, convection like in cold water, and evaporation or respiration through breathing cold air. When we have a patient with hypothermia, we want to check their vital signs and assess their neuro status. Neuro checks are like checking to see if they can feel their fingers and toes, and asking if they know who they are and where they are. Check over their skin on their fingers, toes, ears, and nose for redness, or grayish black skin spots especially if they’ve been out in the cold and are at risk for frostbite. We keep track of their intake and output to make sure their hydrated. Also, check their blood sugars because remember they’ve used  a lot of glucose in the body to maintain homeostasis. So to care for this patient we will warm them with blankets and even warming blanket devices that blow warm air or water through. The doctor will order IV fluids while the patient is rewarming because their vessels are going to start to relax, dropping the blood pressure down. Remember when their vessels were constricted for a long time they went through that cold diuresis where their body removed a lot of fluid.

Alright guys, that’s it for the lesson on hypothermia! Now go out and be your best self today, and as always, happy nursing!