Sweating

The wonderful properties of skin have been the focus of the blogs this month. One of the abilities of the skin is to release small amounts of water, salt, protein, urea, and ammonia when the body becomes warm. This fluid then evaporates, which cools the surface of the skin. This is sweating or perspiration. It can occur anywhere on the outside of the skin. Sweat can occur from body heat that is felt due to warm temperatures in the environment, fever or warm temperature within the body, exercise that creates energy as warmth, or the ‘fight or flight’ syndrome when a threat is sensed.

Some food and fluid can stimulate your body to sweat. Spicy foods can trick your body into thinking the internal temperature is rising, triggering sweat. Food allergies can trigger sweating. Some people eat too much meat and begin to sweat due to the increased energy it takes to break it down. Bioproducts of digested foods can increase the smell of sweat. These are foods such as cabbage, onions, and garlic. Alcohol can stimulate the body to sweat by making it think you are working out.

Sweating is controlled by the autonomic nervous system (ANS). That is the part of the nervous system that works automatically or without your thinking about it, like ensuring that your heart is beating. Injury or disease affecting the ANS will affect the automatic activity of your body, including sweating. Because messages cannot be sent or misinterpreted, signals to and from the body are interrupted at the level of injury. The part of the brain that controls sweating is the hypothalamus. If this part of the brain is affected by injury or stroke, sweating is affected.

After spinal cord injury or other neurological issues, the skin may not be able to produce sweat below the level of injury or in the area of neurological concern. For a few individuals, there may be some areas that produce too much sweat (hyperhidrosis). Most often, after spinal cord injury, sweating does not occur below the level of injury, but hyperhidrosis or excessive sweating occurs above the level of injury. After a stroke or brain injury, excessive sweating may appear on just one side of the body.

Not being able to sweat can lead to overheating the body as the automatic process of cooling (sweating) cannot respond. Other measures can be taken to cool the body. The use of air conditioning controls the environment for cooling. This can also help with humidity control, which is the amount of water vapor in the air. Humidity can occur even in cooler temperatures. Humidity is cumulative in the body, meaning that it collects, making your body warmer. It is more difficult to cool your body due to overheating from humidity. The time to cool off from humidity can take hours, even though it collects in your body in minutes.

Other actions to keep your body cool are finding a shady location when outside, using a fan to create a breeze, and using cooling cloths such as a cold, wet towel or washcloth and drinking cold fluids. A cooler is useful in keeping refreshments and cold clothes available. Be sure you have a cool place that you can go to cool down periodically. Cool your vehicle before getting into it. Heat build-up in a vehicle can zap the energy right out of your body. Dress for warm weather by wearing light colors and light, breathable fabric clothing. Use a wide-brimmed hat that has ventilation openings. Also, do not forget to protect your skin with sunblock and eyes with UVA and UVB protection sunglasses.

Hyperhidrosis or excessive sweating is an issue that can occur regardless of temperature or humidity. This is sweating due to the ANS being unable to regulate sweating throughout the body. Typically, it occurs above the level of injury in spinal cord injury or on the unaffected side after stroke because the ANS is attempting to regulate the entire body temperature but can only control the body not affected by neurological injury. So, sweat just pours out where it can. Although rarer, in some instances, excessive sweating can occur in patches within the area of neurological injury. This can occur due to miscommunication of messages in the ANS.

Excessive sweating can have detrimental effects. Quality of life can be disrupted due to the need for changing clothes, changing bedding and the constant need for drying and cleaning your body. It creates a need to check your skin even more frequently as excessive moisture is more susceptible to skin issues. All the moisture can lead to rashes, skin irritations, blisters, and even pressure injury. In addition, there is more laundry as you have to clean more clothes, sheets and towels.

As for your internal body, excessive sweating can cause dehydration. Management of fluids becomes a challenge as you will need to take in more fluid but still need to balance your output of urine if you are using an intermittent catheterization program. Measuring the amount of fluid output through sweat is a challenge.

Autonomic dysreflexia (AD) is a response phenomenon that results from damage to upper motor neurons due to some spinal cord injuries or brain injuries. It is important to note that excessive sweating can be a sign of autonomic dysreflexia (AD). Be sure to consult with your healthcare provider for an assessment. Typically, AD appears in individuals with higher-level SCI injuries, but it has been noted in those with injury as low as T10 as well as in some individuals with stroke and brain injury. Be sure to check your blood pressure for elevation from your normal sweating episodes. A rise in blood pressure of 20-40 mm Hg systolic higher than your normal indicates an episode of AD. There are symptoms of AD, including the most well-known pounding headache. However, many, many people have AD without the headache. Excessive sweating may be your only symptom, so be sure to contact your healthcare professional to ensure this is not the source of excessive sweating or, if it is, that you can get treatment for AD.

Excessive sweating has also been associated with orthostatic hypotension due to autonomic effects as the blood vessels are attempting to contract and push blood to the brain when elevating the head. It has also been associated with post-traumatic syringomyelia (formation of a cyst in the area of a spinal cord injury, at a later time after the original incident).

Fortunately, there are some treatments for excessive sweating. Not all treatments may be the right one for you. This is a list of possibilities. Discuss each with your healthcare provider and follow their guidance to determine which would be the right treatment for the uniquely you. As with any medication or over-the-counter substance, check with your healthcare professional prior to use. These treatments alter sweat production, which can lead to harmful complications.