MALAYSIA is currently experiencing a severe heatwave across the nation. As of May 17, the Health Ministry has reported 14 cases of heat-related illnesses, of which four have been identified as heatstroke, four as heat exhaustion and the remaining six as heat cramps.

Cases are expected to rise until the middle of this year as the heatwave continues, with temperatures averaging between 33°C and 35°C. The continuously elevated temperatures can adversely affect people, increasing the risk of
heat-related illnesses, which can vary from minor conditions, such as heat cramps, to more severe conditions, such as heat stroke.

Heat stroke

This is a severe heat-related illness, characterised by a significant increase in body temperature (hyperthermia), with little or no sweating (anhidrosis), and can alter sensorium after prolonged exposure to high ambient temperatures.

However, anhidrosis is a late finding and may not be present during physical examination. Core body temperatures above 40°C are usually diagnostic, although heat stroke may seldom occur with lower body temperatures.

Early symptoms include behavioural changes, confusion, delirium, weakness, agitation, slurring of speech, nausea and vomiting.

Other possible central nervous system symptoms include seizures, cranial nerve abnormalities and cerebellar dysfunction. Patients may develop vital organ injury, unconsciousness, multiple organ failure and ultimately coma and death if proper treatment is not given promptly.

Heat exhaustion

This occurs as a result of excessive sweating when the body loses an enormous amount of water and salt. It is characterised by symptoms, such as profuse sweating, dizziness, thirst, reduced urine output and feelings of nausea and vomiting.

In cases of heat exhaustion, the body temperature may be slightly elevated (less than 40°C) or within the normal range. Physical examination may reveal cool and clammy skin. If left untreated or unresponsive to treatment, heat exhaustion can progress to heatstroke.

Heat cramps

These commonly occur in individuals who engage in strenuous activities and experience significant sweating. This condition is often observed in individuals who consume only water or hypotonic solutions. When we sweat, our bodies lose both fluids and salts. Insufficient salt levels can lead to painful muscle cramps, primarily affecting the calves, thigh muscles and shoulders.

Heat rash

Excessive sweating can lead to skin irritation, characterised by redness, red spots or a rash in areas, such as the neck, chest and elbow creases. These symptoms may cause discomfort and itchiness. Prolonged and repeated exposure to heat can even result in chronic dermatitis. The symptoms and signs of heat stroke can resemble those of other central nervous system diseases, such as meningitis or encephalitis.

In early May, there was a misreported case of a 12-year-old boy’s death in Kluang, Johor, initially attributed to heat stroke. The boy exhibited symptoms, such as fever, shivers, agitation and seizure. However, further investigations revealed that the cause of death was actually “septic shock, secondary to meningoencephalitis”, which was unrelated to heat stroke as previously reported.

Therefore, due to the similarities in symptoms between central nervous system diseases and heat stroke, it is crucial to consult trained medical professionals for accurate diagnosis and appropriate treatment.

Treatment of heat-related illnesses

For minor heat-related illnesses, the primary treatment involves rapidly cooling the body temperature. It is important to move the patient to a cool environment, preferably indoors. Clothing should be loosened or removed to enhance heat dissipation through the skin. An effective approach is to combine cool water spray, with continuous airflow over the body, such as using a fan or
air-conditioning unit.

Other cooling methods, such as cold-water immersion can also be used. However, the patient should not be wrapped in wet towels because this will act as insulation and may increase the body temperature instead.

While cold-water immersion can be used as a cooling method, it is crucial not to wrap the patient in wet towels as this can act as insulation and potentially raise the body temperature instead.

In the case of major heat-related illnesses, such as heat stroke, immediate and efficient cooling measures are essential. The patient should be promptly taken to a cool and shaded area. Remove any unnecessary clothing and begin tepid sponging. Apply cool compressions to the armpits, neck, groin and head.

For individuals experiencing heat stroke, it is crucial to arrange for an ambulance to transfer them to the nearest hospital for further medical intervention. Failure to recognise and appropriately manage heat stroke can lead to irreversible injury and even death.

Preventive measures

It is also vital to remain alert and monitor the current weather forecast, especially the heat index, which can easily be accessed on the MetMalaysia website.

People are advised to limit outdoor activities and seek immediate medical attention if they experience symptoms of heat stroke. Wearing dark-coloured clothing should be avoided as it can absorb more heat, potentially raising body temperature. Opting for light-coloured and loose-fitting clothes allows for better sweat evaporation, aiding in body cooling.

Proper hydration plays a crucial role in treatment. It is important to note that feeling thirsty may not be a reliable indicator of fluid needs. Monitoring the colour of urine can serve as a
better indicator, as a dark yellow colour may suggest dehydration and the need for increased fluid intake.

In mild cases, rehydration can be achieved by increasing oral intake of water or, preferably, isotonic drinks to maintain the balance of electrolytes in the body. However, if the patient is unable to tolerate oral fluid, experiencing confusion or unconscious, it is necessary to initiate intravenous (IV) fluids for rehydration and electrolyte replacement.

Refrain from consuming sweet, carbonated drinks as well as alcoholic beverages. Drinking too much coffee and tea is also not advisable as they have a diuretic effect and will lead to more loss
of fluids.

Extra preventive measures for school children

For children, it may take longer for their bodies to increase sweat production compared to adults. Infants and younger children also have more trouble regulating their body temperature, partly due to their limited understanding of the importance of staying hydrated. It is crucial for parents and caregivers to monitor and encourage their children to drink an adequate amount
of fluids.

School teachers also need to play a vital role in ensuring that their students are drinking fluids regularly. Several schools in the Klang Valley have taken proactive measures, such as making periodic announcements, to remind and encourage students to stay hydrated by consuming drinks.

The Education Ministry has taken steps in the right direction by temporarily halting outdoor activities until the weather condition improves.

Additionally, vehicles parked under the scorching sun can get extremely hot and a child should never be left unattended in a parked vehicle. They will be susceptible to confinement hyperpyrexia (a subtype of heatstroke).

Overall, adhering to the above-mentioned preventative steps and staying well-informed is extremely crucial and will reduce the risk of ourselves and our children developing heat-related illnesses.

Dr Punithavathy Shanmuganathan, Senior Lecturer in Family Medicine and Dr Lim Yin Sear, Senior Lecturer in Paediatrics, School of Medicine, Faculty of Health and Medical Sciences, Taylor’s University. Comments: