Sports Injuries & Cold

SPORTS INJURIES AND COLD

Cold injuries are caused by an imbalance between the body’s production and emission of heat. Athletes with cold injuries are unable to maintain homeostasis and balance heat production with loss. In cold conditions, the body’s homeostatic response is peripheral vasoconstriction in an attempt to limit the amount of warm blood circulating in the periphery, where the stored heat is emitted into the environment. If this is not enough to maintain body temperature, the body increases its metabolic rate with the onset of shivers. As with exercise, these muscle contractions generate heat as a collateral effect of their metabolism, which helps maintain body temperature. If these adaptive mechanisms are outweighed by the emission of large amounts of energy into the environment, hypothermia is caused. Cold, humidity and wind contribute to hypothermia. Water is a much better conductor of heat than air, so exercising in rain or high humidity, leads to a much higher rate of heat emission. Wind also has an important role in the emission of heat through evaporation and commutation, so that higher wind speeds cause faster heat emission rates.

HYPOTHERMIA

Hypothermia is defined as body temperature below 35°C. Mild hypothermia consists of body temperatures of 33°C to 36°C, moderate hypothermia at body temperatures of 29°C to 32°C, and severe hypothermia below 28°C. The only accurate way to measure body temperature is to measure rectally with a thermometer capable of reading a temperature below 34°C.

Environmental conditions play a crucial role in determining the rate of heat emission. Cold, humid and windy conditions present the greatest risk for increased heat losses. People with high levels of fat and muscle mass in the body are capable of maintaining their body temperature better than lean athletes. Also, children up to 11-12 years of age and older athletes (>60 years old) are at greater risk of injuries from the cold, due to limitation or delay of thermoregulatory capacity. Some medications (central nervous system depressants, phenothiazides) and some medical conditions (hypoglycemia, hypothyroidism, peripheral neuropathy, exhaustion, malnutrition, smoking, mental illness) as well as alcohol consumption, are also associated with hypothermia. All of these factors inhibit the body’s ability to maintain temperature through reduced heat generation, increased heat emission into the environment, and a lack of sensation of peripheral injuries from the cold.

Athletes with mild hypothermia often have severe shivering, increased blood pressure, fine motor disorders, lethargy, apathy, and mild amnesia. With the progression to moderate hypothermia, the shivering ceases, cardiac disorders and suppression of vital signs may occur. Manifestations of severe hypothermia include mental state disorders, dysarthria, loss of consciousness, severe cardiac arrhythmias, and gross motor disorders.

Prevention is the best strategy for dealing with hypothermia with clothing playing an important role in prevention. Multiple layers of clothing are the best choice. The inner layer (underwear) should be light and allow moisture to be transferred from the skin to the outer tier with minimal absorption. The middle layers provide the most insulation, while the outer layer provides resistance to rain and wind but allows sweat to evaporate into the environment. As the intensity of the exercise increases, the layers can be removed to prevent excessive sweating, which could bring about unwanted cooling during rest.

The athlete with hypothermia should be taken to a warm, protected environment, in which all wet clothing should be removed and the patient reheated. Most patients are glycogen deficient and as long as they can take fluids, carbohydrates may be administered. Reheating can be achieved both with passive methods (i.e. warm clothes) for cases of mild hypothermia, and active methods in more severe cases (heating devices or even hot intravenous fluids, or hot liquefied oxygen in exceptional cases).

FROSTBITE

Frostbite occurs when tissues freeze and is more common on exposed surfaces of the head and limbs as a result of peripheral vasoconstriction. Superficial (superficial) and deep (deep) frostbite are distinguished based on the depth of the wound. In superficial frostbite we have swelling, redness, gray or spotted skin, stiffness and temporary numbness or burning. In deep frostbite, we also observe hard tissues without sparkle, pustules and numbness or anesthesia.

The risk factors are similar to those of hypothermia with additional factors such as the use of petroleum jelly and wearing tight clothing and footwear or any other means that could restrict blood flow to the extremities. The use of petroleum jelly by some athletes, due to the sensation of heat it offers, inhibits the normal protective mechanism and brings about the opposite of the desired results.

In case of frostbite, we must evaluate the patient for possible hypothermia by taking temperature, remove all restrictive and/or wet clothing and shoes, transfer him to a warm environment and warm the extremities. The heating of the arteries should be carried out only if the patient will not be exposed to the cold again, because this aggravates the damage, and is done by taking a hot bath at 40°C-42°C for 10-15 minutes. Alcohol, nicotine and other peripheral vasodilators should be avoided at this stage.

Serous pustules should be cleaned, but bleeding ones only if they restrict movement. The limb should be splinted and placed in an upright position, while antibiotics are given only if there are signs of infection. Anti-inflammatories can be given to control pain and inflammation. Often the true extent of the damage can be seen after some time, when surgical cleaning will be performed, with ulterior complications that may include significant disability, especially in skeletally immature athletes (children and adolescents).