Body Temperature Regulation

Posted by Nurse Linda in Life After Paralysis on July 07, 2021 # Health

The last few weeks have been a discussion of the properties of the skin. Body temperature regulation has been mentioned several times. It is such a significant issue that it needs a closer look.

Body temperature is a process that happens automatically. When you feel warm, your body adjusts by dilating your blood vessels to let your circulation come closer to the skin, where the outside air can cool it. If you think about someone who has become extremely overheated, you can see their face and body become red due to the excessive circulation from dilated blood vessels in the skin. Your body will also expel some moisture like sweat. This small amount of moisture will sit on the skin to help cool your body. Just a small amount is released, so the sweat stays on the skin and does not roll off. The hotter your body is, the more sweat is produced.

When you feel cold, your body will constrict blood vessels to bring the circulation closer to the center of your body, where it is warmer as it is protected by layers of internal organs and fat storage. When very cold, your body begins to shiver, which increases metabolism and creates heat.

These body-created adjustments occur if you are feeling warm or cold from outside your body as being in an environment where the temperature is too hot or too cold. Adjustments can also occur by reacting to temperature changes from within your body due to fever or hypothermia.

You will notice that you cannot control sweating, shivering, or blood vessel constriction and dilation. This is because your body will protect you against temperature extremes automatically or through the autonomic nervous system (ANS). It would be nice to pinpoint the location of the ANS. Then we could say, ‘fix this spot.’

However, the ANS is located throughout the nervous system of the body. It keeps the body going without our thinking about it, and that is a very good thing. However, neurological injury can upset the function of the ANS. Either messages cannot be sent to and from the brain, messages are miscommunicated or slowed, or the responses to the messages are miscommunicated or slowed.

Sometimes, the brain recognizes something is wrong but cannot pinpoint the area of concern, so a general flood of responses is sent. This is autonomic dysreflexia (AD) which is a disruption of the autonomic nervous system. The responses are an exaggeration of the flight or fight response.

Body temperature regulation after neurological changes from trauma or disease is affected by reduced muscle mass and an inability to adjust blood vessel circulation and sweating. In the brain, the hypothalamus controls body temperature. Individuals with brain injury affecting the function of the hypothalamus may have difficulty with body temperature control. Individuals with higher-level spinal cord injury and those with complete injury have more difficulty in the internal regulation of body temperature especially below the level of injury.

There are ways that you can help control your body temperature. If your body has difficulty in controlling body temperature, you can help through external actions. These actions are actually true for anyone with or without neurological issues, but they should be especially followed for those who do.

Assess the environment where you are and where you plan to be. Becoming too hot or too cold happens to everyone, but with neurological injury, your body responses may not react quickly enough for adjustments leading to complications. If the environment is extremely warm or cold, plan to dress accordingly. Remember that you can be overpowered by air conditioning in the summer, making your body too cold even though it is hot outside. In the winter, you can become overheated by sitting too close to a heat source. Therefore, you need to plan to be able to adjust clothing and the environment no matter where you are.

In warm environments such as summer weather, you may become too warm. Symptoms of heat include flushed skin, particularly above the level of spinal cord injury or on one side of your body if you have a brain injury, headache, dizziness, or weakness. You might not notice extreme symptoms, but a companion will.

You can cool your body by moving to an air-conditioned space, sitting in the shade, sitting in a cool breeze, wearing light colored clothes made of breathable fabric, wearing a ventilated wide-brimmed hat, and using a spray bottle to spritz water on your skin. Use cool cloths and drink cool water, which can both be kept in a cooler. If you are outside, bring a beach umbrella to shade your body. Try to rotate your location between outside and in an air-conditioned space to have cooling periods. Cool your vehicle before you enter it. Wear sunblock and UVA/UVB sunglasses.

In cold environments, you may shiver above the level of spinal cord injury or on one side of your body if you have a brain injury, experience slow breathing, pale skin color, slurred speech, and a weak pulse. You might not notice these symptoms, but a companion may.

To keep warm, plan ahead. Trying to warm your body after it is cold is difficult. Wear layers of clothing that traps air around your body. Even though your body may not feel cold, it will react to it. Dress appropriately for cold temperatures. If you use a wheelchair, be sure to put a blanket under your pressure dispersing equipment. The metal retains cold. Sitting in a cold chair with blankets on top of you warms the front of your body, but the cold will still affect the back of your body from transference from your chair. Drink warm beverages, move to a warm location, perform or have someone provide gentile stretching or gentile range of motion to your body to stimulate muscle function and blood flow. This will speed up your metabolism, creating internal body heat.

At times, body temperature regulation is affected from within the body. A fever can increase body temperature from within. Know your usual body temperature average. Everyone’s temperature has some fluctuation from day to day or even hour to hour. An elevated temperature is typically considered to be 101°F (38.33°C). Your average temperature may be slightly lower due to neurological injury, which means a fever may occur at a slightly lower temperature than average. If a fever occurs, get treatment for the illness. Sometimes, fever sources are not easily identified, so laboratory work should be conducted.

Treatment for fever includes fever-reducing medication, removal of warm clothes and blankets, use of cooling cloths, and drinking cold fluids if possible. These actions will make you more comfortable, but the source of the fever should still be found to get treatment for it. For example, masking a fever through comfort measures will not cure the source of the fever if it is from infection.

Exercise is another activity that can increase body temperature from within. Gentile movement generates blood flow to your muscles which increases metabolism and therefore increases heat in your body. The inability to sweat as well as regulation issues by the ANS increases the possibility of overheating your body. When you exercise, prepare by dressing for the environment, both inside and outdoors—exercise in a cool space. Use cooling towels and drink cool fluids. Monitor yourself for overheating to ensure safety.

It can difficult to return to your individual baseline normal once body temperature regulation has been affected by temperature. After a neurological injury, your body temperature can be lower due to inactivity and a slower metabolism. Individuals often use sleep as a way to reset their autonomic nervous system. A nap or sleeping typically restores the ANS back to their normal body temperature. If you feel you are in danger due to overheating or cold temperatures, be sure to alert healthcare professionals. Both overheating and cold temperatures can greatly affect your health. Nurse Linda

Pediatric Consideration: Children become engaged in an activity and may not be aware of the dangers of overheating or cold temperatures. When engaged in a fun activity, all children do not want to stop what they are doing. It is up to the parent or caregiver to notice when a child might have temperature adjustment issues. Planning by dressing appropriately, having cool down and warming locations, cool drinks and towels on hand are important. Also, remember your vehicle should be cooled or warmed before the child enters. That is an area of great concern as vehicles become so hot or cold. Nurse Linda

Linda Schultz, Ph.D., CRRN, a leader and provider of rehabilitation nursing for over 30 years, and a friend of the Christopher & Dana Reeve Foundation for close to two decades. Within our online community, she writes about and answers your SCI-related healthcare questions in our Heath & Wellness discussion.

The National Paralysis Resource Center website is supported by the Administration for Community Living (ACL), U.S. Department of Health and Human Services (HHS) as part of a financial assistance award totaling $8,700,000 with 100 percent funding by ACL/HHS. The contents are those of the author(s) and do not necessarily represent the official views of, nor an endorsement, by ACL/HHS, or the U.S. Government.