Shielding yourself from scorching sun

Dr Vishali Kotwal

vishalikotwal@gmail.com

Heat related illness is one of the deadliest but preventable weather-related illness. It is more common in areas that do not typically experience periods of prolonged hot weather. It is seen more often early during onset of extreme summer as the body has not yet acclimatized and behavioral changes have not yet started. India is one of the most heat-vulnerable countries. Indian Meteorological department has repeatedly recorded longer and intense heat wave periods in recent years and this trend is continually on the rise due to global warming. South Asia is warming faster than the global average due to urbanization, deforestation and declining ground water levels. Urban heat Island effect is being observed in dense cities like Delhi because of enhanced night temperatures due to concrete infrastructure and little green cover which inhibits recovery from daytime heat. The problem is much more than visible on the surface as public health officials routinely acknowledge that the actual number of heat stroke cases and deaths are likely much higher than official figures suggest. Discrepancies exist because many state health facilities severely underreport or delay confirming heat as the primary cause of death or underlying heat trigger affecting mortality in various diseases.

Heat illness occurs due to inability of body to cope with heat and it can manifest in the milder forms as heat rash, heat cramps or severe forms like heat syncope, heat exhaustion which if not treated can lead to the most dangerous presentation that is heat stroke. Heat Cramps is the mildest form and the earliest warning sign which occurs due to excessive sweating and loss of sodium and potassium. It can be relieved by applying firm gentle pressure or slowly stretching the muscle to release the spasm. One should stay salted which means just don't drink plain water but also salt-enriched fluids or salty snacks. Heat syncope is when a person faints on standing too long or rising suddenly in a hot environment. Treatment is to immediately shift the patient in a cool and preferably air-conditioned environment, make him lie down and elevate the legs slightly, loosen up the clothes and make him sip electrolyte water if conscious. To prevent heat syncope, avoid standing still in a hot environment with occasional bending of knee and standing on your toes. Also, one needs to acclimatize gradually over a period of 10 to 14 days and not start any activity or sitting in a hot environment for too long suddenly.

Heat exhaustion is the body's warning that it is overheating, caused by heavy fluid and salt loss. Its symptoms are extreme tiredness and fatigue with heavy sweating. Skin is pale, cold and clammy, Temperature is usually elevated between 100-to-104-degree Fahrenheit. Pulse is fast but weak. It is a serious condition but treatable at home if cooled within 30 minutes. Patient needs to be hydrated with chilled water with electrolytes.

Heat stroke is the most severe heat related illness where body temperature is higher than 104-degree Fahrenheit associated with unconsciousness. It can be of two types. Exertional and non-exertional or classic.

Exertional heat stroke is seen in young people who engage in strenuous physical activity for a prolonged period in a hot environment like athletes, fire-fighters and military personnel. It is generally preceded by abdominal or muscular cramps, nausea, vomiting, diarrhea, headache, dizziness, dyspnea and weakness which goes unrecognized. Risk factors for this include preceding viral illness, dehydration, obesity, lack of sleep and poor physical fitness.

Classic or non-exertional heat stroke is seen in sedentary elderly, chronically ill and very young people. Risk factors for this include conditions with either increased heat production like infections, hyperthyroidism, epilepsy, stimulant use like cocaine or decreased heat loss like skin diseases, burns, intake of antiallergics, antidepressants, antipsychotics, medications for heart problems. Also, patients with neurological disorders, sedative intake, bed-ridden patients, those with co-morbidities and on multiple medications are more prone.

Clinical features of heat stroke include dry and hot skin, no sweating, irritability, irrational behavior and coma. Heart rate increases, blood pressure is decreased. There can be seizures, bleeding from multiple sites, jaundice, kidney failure and multiple organ failure.

Long term consequences of patients who survive include personality changes, paralysis, gait problems and memory problems, cardiovascular problems, kidney disorders, chronic tiredness, anxiety, disturbed sleep, emotional and psychological distress.

Treatment includes aggressive lowering of body temperature to below 102 degrees Fahrenheit during the initial one hour or golden hour. This can be done by cold water immersion where possible, covering the patient with ice water- soaked sheets after removing the patient's clothes, keeping ice packs in axilla and groins. Till ice is arranged removing all of the patient's clothes and intermittently spraying the patient's body with tepid water while a powerful fan blows across the body.

Paracetamol has no role in the treatment of heat stroke.

PREVENTION

The core challenge in the prevention of heat related illness is that people's perception of local heat risk often differs sharply from expert assessments, limiting protective behaviors and effective policy responses. It means the extreme heat risk is rising faster than public awareness and past experience alone is a poor guide to future danger. People mostly underestimate their local heat risk due to their past weather and lived experience, but climate change is pushing heat risk beyond what many communities recognize.

The biggest danger zones are where risk is high and concern is low. Many rural, older and high poverty zones face serious heat risk with little public awareness undermining preparedness and adaptation. So, we need to target climate risk communication, public health outreach and adaptation investments where they are most needed.

Education is most important and this involves media, public education, public health programs, athlete safety programs

It is very important to recognize risk factors and modify behavior which includes:

1) Avoiding medications which increase risk .

2) Avoiding physical activity during peak hours between 12 noon to 4 pm.

3) Outdoor workers like labourers, street vendors, traffic personnel and farm workers should drink fluids preemptively on schedule

that is 750 ml of water every hour and not based on thirst only.

4) Supplement water with electrolyte rich fluids, butter-milk, coconut water or lemon water to replace lost salts.

5) Do not consume alcohol, tea, coffee or high sugar carbonated drinks while working in the heat.

6) New workers should acclimatize over 1 to 2 weeks to gradually build up their tolerance.

7) Frequent cooling breaks at regular intervals in cool, shaded or ventilated areas are mandatory.It should be noted that even short

stays in an air-conditioned environment may drastically reduce the incidence of heat stroke.

8) Use light weight, light coloured and loose-fitting cotton clothing.

9)Use wide brimmed hats, umbrellas and protective eye wear.

10) Cooling aids like bandanas or damp clothes soaked in cool water should be placed around neck and head.

11)Watch for red flag symptoms like heavy sweating, dizziness, headache, muscle cramps, nausea, decreased or excessively yellow coloured urine.

CONCLUSION

Heat related illness is a dangerous but preventable problem.

Strategies to mitigate heat stroke risk include early warning system, public awareness campaigns, emergency response process, creation of public cooling centers, infrastructure upgradation and enhancing tree plantation.

(The author is ex- Professor, Deptt of Medicine, GMC, Jammu)