Neonatal hypothermia accounts for a significant proportion of neonatal mortality globally, mostly as comorbidity of severe infections and prematurity. Appropriate thermal protection is crucial in reducing this burden.
Routine hand-touch temperature monitoring is a cost-effective and simple tool for detecting physiological cold stress, especially in low-resource settings. However, standard randomized controlled trials are needed to evaluate the effectiveness of this approach.
Symptoms
Neonatal cold injury syndrome can occur in newborns when they’re exposed to very low temperatures for too long. This can cause severe damage to the skin, tendons, and nerves, and it’s often fatal. This condition can affect any part of the body, but it’s most common in the nose, toes, fingers, and cheeks. Symptoms include coldness, numbness, refusal to eat, and edema (swelling).
The most common cause of frostbite is being exposed to very cold weather for a long time without proper clothing and shelter. It can also happen when bare skin makes contact with cold objects, such as freezing metal or ice. People who are at higher risk of getting frostbite include older adults, children under the age of 18, those with a weakened immune system, and people with medical conditions like peripheral vascular disease, Raynaud’s syndrome, diabetes, or hypothyroidism.
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Babies, especially newborns, are more likely to get frostbite because of their size and sensitivity to temperature changes. They have a larger surface area compared to their weight and can’t regulate their body heat as well as adults. They also don’t have a lot of fat under their skin, which helps them retain body heat. Additionally, they’re not able to produce as much energy by shivering, which is another way the body warms itself up.
In cases of severe frostbite, the lower layers of the skin freeze and become completely numb. The numbness is very painful, and you may notice swelling in the affected area and discoloration. The skin may also develop big blisters that break easily. Over time, the frostbitten skin may turn black, and the affected tissue dies. This can lead to gangrene, which needs to be surgically removed by a doctor.
Newborn therapeutic hypothermia, which is a process of slowly lowering your baby’s body temperature, can help prevent neonatal cold injury and improve their chances of survival. This treatment can be used in the delivery room before and after birth, during transport to the hospital, and even in the NICU.
Diagnosis
Neonatal cold injury syndrome occurs when your newborn is exposed to an extreme cold environment, causing their core body temperature to drop, which can cause brain damage. This condition is often fatal, and surviving infants may have permanent brain damage or developmental delays.
This syndrome is typically caused by environmental exposure, but it can also be the result of disorders that impair thermoregulation (eg, sepsis or intracranial hemorrhage) or underlying medical conditions that are associated with increased risk for hypothermia, including prematurity, cesarean section, maternal hypertension, and low Apgar score.
Symptoms of the condition include skin pallor, decreased urine output, apathy or lack of movement, a dry mouth, a bluish color to the fingers and toes, and a fever. The condition is usually fatal unless treated promptly and adequately.
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The best way to diagnose neonatal cold injury is by monitoring your baby’s core temperature, as well as their extremity temperatures. The goal is to catch the condition before it gets worse, which can be difficult when your baby is not moving and exhibiting the symptoms.
Newborn therapeutic hypothermia, or “body cooling,” can help your baby’s body recover from the effects of a severe newborn cold injury. This treatment lowers your baby’s core temperature to 92 degrees Fahrenheit, which slows the metabolism of their brain so that the damaged cells can be repaired. This can prevent a serious condition known as hypoxic ischemic encephalopathy, or HIE, which can lead to seizures and developmental delays.
A recent study found that most healthcare professionals acknowledge the importance of the WHO’s warm chain guidelines for optimal thermal care of neonates, but that they rarely practice them. The study surveyed 55 neonatal care professionals in two rounds of the questionnaire; participants included medical doctors, nurses, and midwives. Almost all of the participants acknowledged that checking an infant’s extremity temperature is important for the detection of cold stress, but many indicated that they did not know how to check the temperature by hand, and that they were concerned that a clinical assessment with their hands might not be as accurate as a formal measurement with a thermometer.
Treatment
The treatment options for Neonatal Cold Injury include therapeutic hypothermia, supportive care, resuscitation and stabilization (e.g., restoring blood pressure and oxygen saturation), correction of metabolic disturbances (hypotension, acidosis and hypoventilation) and monitoring multiorgan dysfunction. Neonatal therapeutic hypothermia significantly reduces the risk of severe brain damage, as well as a range of long-term complications.
Neonatal cooling treatment is usually started immediately after the baby’s birth and can be done by lowering the body temperature to around 33°C. The duration of treatment is typically 72 hours. Studies have shown that the neuroprotective effects of neonatal hypothermia are greater the earlier it is administered. However, in low resource countries due to multiple antenatal insults, delayed hospital admissions in obstructed labor and long delays in carrying out emergency caesarean sections it is possible that by the time the baby reaches a hospital and can receive hypothermia therapy the window of opportunity may have already passed.
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Physiologically, the cold environment triggers early induction of a thermoneutral temperature, which is achieved through vasoconstriction to minimise heat loss from the hands and feet as well as a rise in metabolic rate to produce more heat. The onset of this condition, physiologically termed cold stress, usually occurs before hypothermia and can be detected by peripheral temperature monitoring, especially by hand-touch (Table 2). Temperature monitoring is crucial for neonatal thermal care, but standard axillary or rectal temperature measurement using a thermometer is not routinely available in low-resource settings.
Localized cold injury is often observed in association with hypothermia but can occur as a standalone diagnosis. It can cause a variety of symptoms such as apathy, refusal to feed, oedema and seizures. It is characterized by red-brown or purplish skin changes and by the feeling of coldness in the affected areas. The severity of the cold injury is rated by degrees and is classified as first, second, third or fourth degree frostbite.
A simple and cost effective method for detecting physiological cold stress is the ‘hand-touch’ temperature assessment. This is a simple, non-invasive and easy to use technique which can be used in most healthcare settings including during skin to skin care. The authors suggest that the use of a hand-touch temperature assessment could be an important step towards improved neonatal thermal care and reduced neonatal mortality in clinical practice in low-resource settings.
Prevention
Neonatal cold injury is a major cause of neonatal morbidity and mortality. Accidental hypothermia and localized cold injuries (frostbite) can occur due to environmental exposure, physiological function, or other factors. This Healthwise In Brief reviews accidental hypothermia and localized cold injuries, their definitions, occurrence status, associated risks, presentations, and prevention.
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Current WHO guidelines recommend checking skin temperature by hand-touch only when a thermometer is not available. However, this contextual recommendation may confuse healthcare professionals into believing that a hand-touch temperature assessment is of lower ‘value’ than a technical assessment with a thermometer. Physiological cold stress is a common risk factor for neonatal death, and routine hand-touch temperature assessments during skin to skin care are an effective method of preventive thermal management, especially in low-resource settings.
