Management
Treatment of the victim of near-drowning can be attempted even before rescue from the water. Having said this, basic life support is difficult unless the rescuer has a firm foothold. Rescuers must always make a safe approach, otherwise further unnecessary deaths may occur.
Once on dry land the child’s airway should be opened and cleared but attempts at emptying the lungs of water are time wasting and fiitile. Fluid filled lungs have reduced compliance and so require higher inflation pressures. Resuscitation follows standard guidelines and most survivors will usually start to breathe after about 5 minutes.
The stomach is often full of water and vomiting often follows successful resuscitation attempts. Stomach decompression and intubation guards against this and both should be achieved once resuscitation has got underway. Once the child has been intubated, continuous positive airways pressure (CPAP) and positive end expiratory pressure (PEEP) are useful in ventilating stiff lungs.
Near-drowning can be complicated by a number of other factors, which must be borne in mind during resuscitation attempts. Many drowning incidents result from children falling or diving into water. In these circumstances the child could also have been injured and the rescuer should assume this until it can be ruled out. Particularly when there has been a diving accident in shallow water, there is significant risk of a cervical spine injury and the neck must be adequately immobilized until this possibility can be excluded.
The large surface area: volume ratio of children means that even during warm weather hypothermia is a common feature of near-drowning. A core temperature should be determined at an early stage during resuscitation using a low reading thermometer.
Hypothermia is a mixed blessing. Although its presence hampers resuscitation attempts, rapid cooling slows the metabolic rate and protects the vital organs. Children have survived long periods of submersion in cold water and resuscitation attempts should be equally prolonged. Survival has been recorded in children after an hour following submersion in cold water. Cardiac arrhythmias are frequently seen at low body temperatures, which also make them all the more difficult to treat. Ventricular fibrillation is often refractory at core temperatures below 30°C. Resuscitation should not be abandoned until the child has been rewarmed to at least 33°C. A child should not be declared dead until it is ‘warm and dead’.
Rewarming
The techniques used to rewarm a child depend on the degree of hypothermia. Methods are divided into external and core rewarming but must not hamper CPR.
External rewarming alone is usually adequate where core temperature is more than 32° C. Below 32°C, core warming is necessary. The means used depend on the skills of the rescuers and the facilities available
Means of external rewarming, temperature >32°C
• Remove wet clothing
• Dry child
• Wrap in warmed blankets
• Use radiant heat lamp
Means of core rewarming, temperature <32°C
• Infusion of warm intravenous fluids (at 43°C)
• Ventilation with warm gases (at 43°C)
• Instillation of warm fluids into body cavities (at 43°C)*
• Cardiac bypass
*Instillation of warm fluids into body cavities is used by some, but thought to
confer no advantage to others.
Indicators of outcome
Abandoning resuscitating is always a difficult decision and should ideally be made by a senior doctor. As already mentioned, despite an initially poor outlook, children have still survived. A number of factors may help when coming to a decision. The majority of successful resuscitations occur in children who have had submersion times of less than 10
minutes
Indicators of good outcome
• Submersion for <10 minutes
• Submersion in cold water
• Initial core temperature below 33°C preserves vital organ (especially brain)
function
• Initial spontaneous breath in first few minutes
Indicators of poor outcome
• No spontaneous respiratory attempt within 40 minutes
• Arterial pO2 less than 8.0 kPa (60 mmHg) despite resuscitation
• Blood pH below 7.0 despite resuscitation
• Persisting coma
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