Drowning and non-lethal immersion in water

Non-immersion in water (incomplete drowning) - asphyxiation in water, not leading to death; incomplete drowning causes hypoxia due to aspiration or laryngospasm. The consequences of hypoxia may include brain damage and multiple organ failure. Patients are examined using chest x-ray, oximetry, or blood gas analysis. Treatment is supportive, including lifting the heart block, restoring breathing, arresting hypoxia, hypoventilation and hypothermia.

Drowning, or fatal asphyxia in the water, ranks 7th among causes of death in case of accidents in the United States and 2nd place among children 1-14 years old. Most often, children under the age of 4 are drowning, as well as children from disadvantaged families and immigrants. Risk factors for people of all ages are the use of alcohol or drugs and conditions that cause temporary loss of legal capacity (eg, seizures, hypoglycemia, stroke, MI). Incomplete drowning most often occurs in swimming pools, hot tubs, natural water bodies and, among infants and toddlers, in toilets, baths, buckets of water or detergent solutions. For each death from drowning, there are approximately 4 incomplete drownings leading to hospitalization.

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Pathophysiology of drowning and non-immersion immersion in water

Hypoxia is the main factor of incomplete drowning, which has a damaging effect on the brain, heart and other tissues. After stopping breathing, cardiac arrest may follow. Hypoxia of the brain can cause it to swell and, often, persistent neurological consequences. Generalized tissue hypoxia can cause metabolic acidosis. Initially, hypoxia occurs due to aspiration of water or gastric contents and acute reflex laryngospasm, or both. Damage to the lung by aspiration or hypoxia itself can cause subsequent secondary hypoxia. Aspiration, especially with solid suspensions or chemicals, can lead to aspiration pneumonitis (sometimes primary or secondary to bacterial pneumonia) and may worsen the alveolar secretion of the surfactant, which usually leads to focal lung atelectasis. Extensive atelectasis can make damaged areas of the lungs rigid and poorly ventilated, potentially causing respiratory failure with hypercapnia and respiratory acidosis. The perfusion of poorly ventilated areas of the lung (ventilation / perfusion imbalance) aggravates hypoxia. Alveolar hypoxia can cause non-cardiogenic pulmonary edema.

Laryngospasm often limits the volume of aspirated fluid; but in some cases large volumes of liquid, aspirated with incomplete drowning, can change the concentration of electrolytes and the volume of blood. Sea water can slightly increase the content of Na ⁺ and CI. "Conversely, large amounts of fresh water can significantly reduce the concentration of electrolytes, increase the volume of circulating blood and cause hemolysis." Damage to bones, soft tissues, head and internal organs is possible. Water, there may be fractures of the cervical and other parts of the spine (which can lead to drowning) .The effect of cold water causes systemic hypothermia, which can be a serious problem .However, hypothermia may also occur yvat protective effect by stimulating the reflex of "diver", slowing the heart rate, constricting peripheral arteries and, thereby redistributing the oxygenated blood from the limbs and intestines to the heart and brain. In addition, hypothermia decreases the tissue need for O ₂, prolonging the victim lives and delaying The beginning of hypoxic tissue damage The reflex of the "diver" and the protective clinical effect of cold water are generally more pronounced in young children.

Symptoms of drowning and non-immersion in water

Children who do not know how to swim can go under water in less than a minute, much faster than adults. After recovery, excitement, vomiting, raucous breathing and impaired consciousness are characteristic. The patient may have respiratory failure with tachypnea and cyanosis. Sometimes the symptoms of respiratory failure develop several hours after immersion in water.

Diagnosis in most people found in or around water is based on obvious clinical data. First of all, it is necessary to return a person to life, and then carry out diagnostic studies. If there is a suspicion of damage to the cervical spine, it must be immobilized, including those who are unconscious and people whose mechanism of damage is probably related to diving. Attempts to remove water from the lungs do not have much effect. It is necessary to take into account the probability of a drowning person having a secondary craniocerebral trauma and conditions that could contribute to drowning (for example, hypoglycemia, stroke, MI).

In all patients, oxygenation of the blood is assessed by oximetry; in the presence of respiratory symptoms, chest X-ray and blood gas analysis are performed. Since respiratory symptoms can occur after a period of time, patients who do not have them, however, are transported to the hospital for observation for several hours. Patients with symptoms or anamnesis of prolonged immersion under water measure body temperature, remove ECG, determine the concentrations of plasma electrolytes, start constant oximetry and cardiomonitoring. Patients with possible damage to the cervical spine perform a visualizing method of investigation. Victims with impaired consciousness perform a CT scan of the head. If any other pathological conditions are suspected, appropriate research methods (for example, blood glucose concentration, ECG, etc.) are performed. In patients with pulmonary infiltrates, bacterial pneumonia, differential diagnostics with aspiration pneumonitis is carried out with the help of blood sowing, as well as sowing and staining by Gram sputum.

Forecast and treatment of drowning and non-immersion immersion in water

Factors that increase the chance of a drowning person to survive without permanent consequences are:

• short duration of immersion;
• colder water temperature;
• younger age;
• absence of concomitant diseases, secondary trauma and aspiration of solid impurities or chemicals;
• and, most importantly, as quickly as possible the onset of resuscitation.

In cold water, survival is possible even after staying in it for more than an hour, especially in children. Thus, the patient must be actively revitalized even after prolonged exposure to water.

The treatment is aimed at correction of cardiac arrest, hypoxia, hypoventilation, hypothermia and other pathological conditions. If the patient does not breathe, it is necessary to restore breathing immediately, if necessary - even in the water. If immobilization of the spine is required, it is carried out in a neutral position, in parallel artificial respiration is performed, pushing the lower jaw forward without tipping the head or lifting the lower jaw. If necessary, start a closed cardiac massage followed by a transition to an extended cardiorescription; provide oxygenation as soon as possible intubating the trachea. Patients with hypothermia should be warmed as quickly as possible.

Patients with signs of hypoxia or moderate symptoms are hospitalized. In hospital continue treatment aimed at achieving acceptable values of arterial O2 and CO2. It may require artificial ventilation. Give 100% O2; the concentration is reduced depending on the results of the analysis of the gas composition of the blood. To expand and maintain the permeability of the alveoli, which in turn supports oxygenation, ventilation may be required with positive end-expiratory pressure or with positive alternating pressure; Respiratory support may be needed for hours or days. The supply of inhaled p-adrenomimetics through the nebulizer stops bronchospasm and reduces rales. Patients with bacterial pneumonia are given antibiotics directed to microorganisms detected or suspected on the basis of bacteriological tests of sputum or blood. Glucocorticoids do not use.

The need to introduce a liquid or electrolytes to correct the electrolyte imbalance is rare. Limitation of fluid is usually not shown, even with swelling of the lungs or brain. With prolonged hypoxia, treatment does not differ from that after cardiac arrest.

Patients with mild symptoms and normal oxygenation can be observed in the emergency room for several hours. If symptoms are resolved and oxygenation remains normal, they can be discharged, warning of the need to return when symptoms return.

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Prevention of drowning and non-immersion in water

Use of alcohol or drugs, the main risk factors, should be avoided before swimming, boating or looking after children near the water.

Less experienced swimmers should always be accompanied by well-floating people, or the place of bathing should be safe. Swimming should be stopped if a person feels that it is cold, because hypothermia can lead in the future to an inadequate self-esteem. When swimming in the ocean it is necessary to learn to avoid the surf waves, swimming parallel to the shore, and not towards it.

Children should have devices that support buoyancy, both during bathing and near water. Children should always be watched by an adult, regardless of location - the beach, pool or pond. For infants and toddlers, it is also necessary to look after, ideally at arm's length, near the toilet or containers (bucket, basin) with water, which it is better to pour out immediately after use. Swimming pools should be surrounded by a fence with a height of at least 1.5 m.

In boats it is better to put on all life jackets, especially those who do not know how to swim and small children. Exhausted, the elderly and with convulsive diseases or other diseases that can lead to a loss of consciousness while in the water or walk on a boat, require special attention.

In places of mass bathing there should be trained rescuers. Comprehensive community prevention programs should focus on at-risk groups, teach children to swim as early as possible, and, if possible, introduce adolescents and adults to the basics of cardiopulmonary resuscitation.