Medical problems of the rescued castaway on board the rescue vessel
The treatment of survivors on board a rescue vessel depends on the type of rescue facility available and the number as well as the medical condition of the survivors. As soon as survivors are brought aboard, the personnel must quickly assess and classify them based on their physical condition. Those with minor injuries that will not worsen if treatment is delayed should be attended to later or as time permits. On the other hand, those who are sick or injured but can be treated with the available facilities must be given priority, especially those requiring urgent medical attention. In some cases, individuals from this second group may receive basic first aid and then be moved to the lower priority group. For example, a fractured arm can be quickly immobilized with a splint and treated more definitively after more serious conditions have been managed.
Victims rescued from drowning require immediate treatment, following the principles of basic life support. Even if a person appears to need only minimal treatment after submersion, it is advisable that they be transferred to a hospital for further observation and follow-up care.
Cold exposure injuries affecting specific parts of the body, such as the face and extremities, are caused by exposure of tissues and small surface blood vessels to very low temperatures. The severity of these injuries depends on several factors, including the temperature, duration of exposure, wind speed, humidity, lack of proper protective clothing, and whether clothing is wet. Additional factors such as fatigue, individual susceptibility, existing injuries, emotional stress, smoking, and alcohol consumption can worsen the effects of cold exposure. These localized cold injuries are generally classified into three types: chilblains, immersion foot, and frostbite.
Chilblains are a relatively mild form of cold injury that occurs in moderately cold and humid climates, typically at temperatures above freezing. They commonly affect areas such as the ears, fingers, and the back of the hands, although the lower limbs may also be involved. The condition is characterized by a bluish-red discoloration of the skin, mild swelling, and sensations of itching or burning, which may worsen when the affected area is warmed. If the exposure is brief, these symptoms may disappear without leaving any lasting effects. However, repeated or prolonged exposure can lead to chronic changes, including increased swelling, deeper discoloration of the skin to a reddish-purple shade, formation of blisters, and even ulcers that heal slowly and leave pigmented scars. Treatment involves applying soothing ointments such as petrolatum to relieve discomfort. Individuals prone to chilblains should avoid cold conditions or protect themselves by wearing warm clothing such as woollen gloves and socks.
Immersion foot is another type of cold injury caused by prolonged exposure of the feet to cold water at temperatures above freezing, usually below 10°C, for more than 12 hours. It is commonly seen in shipwreck survivors who remain in lifeboats or rafts under conditions of inactivity, poor nutrition, wet and tight clothing, and harsh weather. The symptoms include swelling of the feet and lower legs, numbness, tingling, itching, pain, cramps, and changes in skin colour. In cases where there is no additional trauma, tissue destruction is usually absent. After rescue, care must be taken to avoid rapid rewarming of the affected limbs. The skin should be handled gently to prevent damage, and any blisters should not be broken. Massage of the affected areas should be avoided. Preventive measures include keeping the feet warm and dry, loosening shoelaces, elevating the feet, and performing regular toe and ankle exercises. When possible, shoes should be removed, and spare clothing can be wrapped around the feet for warmth. Smoking should also be avoided, as it worsens circulation and increases the risk of injury.
Frost-bite
Frost-bite is a severe form of cold injury in which body tissues are damaged due to freezing. It is the most serious type of localized cold injury. Although the affected area is often small, frost-bite can sometimes involve larger regions. The parts of the body most commonly affected include the fingers, toes, cheeks, ears, and nose. If exposure to cold continues for a long time, the freezing process may extend further up the arms and legs.
The formation of ice crystals within the skin and underlying tissues causes the affected area to appear white or greyish-yellow in colour. Pain may be present in the early stages but often decreases as the condition progresses. In many cases, the affected part feels extremely cold and numb, sometimes accompanied by tingling, stinging, or aching sensations. The individual may not even realize that frost-bite has occurred until it is pointed out by someone else.
In cases of superficial frost-bite, the surface of the skin feels hard while the underlying tissue remains soft when gently pressed. However, in deep and unthawed frost-bite, the area feels completely hard and solid and cannot be depressed. It remains cold and numb, and within 12 to 36 hours, blisters may develop both on the surface and in deeper tissues. As the affected area thaws, it becomes red and swollen. In severe cases, gangrene may develop, leading to tissue death (necrosis). The exact severity of frost-bite can only be determined over time. Fortunately, the treatment approach is generally similar for most types, except for superficial frost-bite, which should be thawed immediately to prevent deeper injury. However, a frozen limb should never be thawed unless proper facilities are available to ensure rapid and controlled rewarming.
Treatment of frost-bite follows three main stages: first aid, rapid rewarming, and post-treatment care. The primary aim of first aid is to move the patient to a location where proper medical treatment is available as quickly as possible and then begin rewarming. A person with frost-bitten feet may still be able to walk long distances without immediate harm, but once rewarming has started, it must be continued without interruption. Walking on partially thawed tissues or allowing them to refreeze can cause severe damage. During transport and initial care, alcohol must not be given, as it interferes with circulation and increases heat loss. Ointments and creams should also not be applied at this stage.
Rapid rewarming involves two aspects: treating overall cold exposure and treating the local frost-bitten area. General rewarming is achieved by removing all cold, wet, or tight clothing such as shoes and socks, and replacing them with warm items. Warmth should be provided both externally and internally. External warming includes using prewarmed clothes, blankets, or sleeping bags. Giving cold replacements should be avoided, as they can further reduce body heat. In some cases, sharing body heat with another person can be an effective way to provide warmth. Internal warming is achieved by giving hot drinks and ensuring adequate nutrition.
Generalized immersion hypothermia aboard the rescue vessel
When a person is exposed to environmental temperatures below approximately 20–21°C, survival depends on several factors, including body insulation (such as body fat and clothing), the ratio of body surface area to volume, metabolic rate, and the individual’s determination to survive. Seawater freezes at around –2°C, and polar waters are often at or near this temperature. In such extreme conditions, the body loses heat very rapidly. Consciousness may last only 5 to 7 minutes, the hands may become unusable within 1 to 5 minutes, and death can occur within 10 to 20 minutes. Severe exposure of the head and neck to cold can even lead to serious conditions such as cerebral haemorrhage, so these areas must be carefully protected.
For individuals rescued from cold water, measuring rectal temperature is important, as it helps in assessing the severity of hypothermia and estimating the chances of survival. When body temperature falls below 35°C, hypothermia begins to affect normal body functions. There is a progressive decrease in metabolic rate, heart rate, and blood pressure, along with uncontrollable shivering. As the temperature drops further to between 27°C and 30°C, symptoms such as hallucinations, apathy, stupor, or unconsciousness may occur. At even lower temperatures, between 21°C and 28°C, death may result due to ventricular fibrillation or cardiac arrest.