What is Drowning, it is a cause of death that may result from asphyxia by inhalation of fluid into the respiratory tract, or from the complex biochemical and hemodynamic changes that follow the inhalation of fluid during immersion.
Accidents account for most drownings, and victims of drowning are often children or other persons who have not learned to swim. Less frequently, drowning may result from suicide or homicide. The circumstances for accidental drowning may include the following: (1) disasters such as floods and tidal waves, as well as shipwrecks and vehicular accidents; (2) hazardous environmental conditions of aquatic sports or occupational activities; and (3) disability while swimming when there is pre-existing illness, intoxication by ethanol or drugs, exhaustion, or overexertion.
Incidence and Prevalence Of Downing
Each year in the United States, there are over 6000 deaths by drowning and approximately the same number of near-drownings. Drowning is the fourth most common type of accidental death. When underwater accidents are considered alone, drowning is the most common cause of death. It occurs more frequently than deaths from barotrauma, including air embolism and decompression sickness, discussed in the article titled Alterations in Atmospheric Pressure. Several million Americans engage in the sport of underwater swimming, using either self-contained underwater breathing apparatus (scuba) or snorkel. Aquatic accidents may constitute a public health problem in certain geographic areas where underwater swimming is prevalent.
- Survivors of near-drowning and studies with laboratory animals have provided knowledge of the sequence of events that occur during drowning. The victim of drowning or near- drowning usually experiences panic at the time e of complete immersion, and struggles to reach the surface. Small amounts of water may be inhaled or swallowed. It is common to hold the breath and to persist in this until accumulation of carbon dioxide stimulates the respiratory center. At the time it is no longer possible to restrain the urge to breathe, pulmonary carbon dioxide tension is high and pulmonary oxygen tension is low.
- Gasping, inhalation of water or other liquid, and loss of consciousness are associated with coughing, vomiting, convulsions, and finally death. In about 10 to 15 per cent of cases, however, the initial aspiration of fluid causes laryngospasm and closure of the glottis, resulting in reflex cardiac inhibition, cardiac arrhythmia, or asphyxia. Rescue prior to the terminal inhalation of fluid, as well as appropriate treatment, may interrupt the course of fatal events and bring on spontaneous recovery. Prompt action is required, for death may occur within several minutes after the victim experiences distress during immersion.
- The mechanism for drowning in sea water, however, is probably different. As the result of the aspiration of sea water, salts pass into the circulation and fluids diffuse into alveoli. Serum electrolytes, particularly chloride and magnesium, increase markedly. Hypovolemia, hemoconcentration, and hypoproteinemia occur. Increased vascular permeability, endothelial damage, and diffusion of plasma into the alveoli are manifested by pulmonary edema and production of frothy white foam in the airway.
- In persons who survive near-drowning and in human victims of drowning, the pathophysiologic mechanisms seem less well understood and may differ from experimental findings. The majority of human victims of drowning aspirate 10 ml. of fluid or less per pound of body weight. Although biochemical and hemodynamic changes have been stressed previously, clinical evaluations of near-drowning victims suggest that fluid and electrolyte balance is restored rapidly. Significant changes in serum electrolytes and volume of blood have been uncommon. Hemodilution has not been demonstrated, but hemoconcentration may be evident in victims of near-drowning in both freshwater and seawater.
- The pathologic findings are often nonspecific. The white or bloody foam, usually seen in the mouth, nose, and tracheobronchial tree, may not be evident after attempts at resuscitation. Often the skin of the palms and soles is wrinkled and pale. These changes, known as “washerwoman’s skin,” are consistent with immersion but they are not pathognomonic of drowning. Lacerations or incised wounds of the skin, without evidence of vital reaction, reflect the effects of tides, collision of the body with underwater obstacles, and postmortem injuries inflicted by sharp objects such as motorboat propellers. Mutilation of a body by aquatic animals, particularly the soft tissues about the eyes, nose, and aps, is common.
The victim of drowning usually experiences breath-holding and burning suffocation, as well as loss of consciousness and inhalation of fluid. On occasion, the victim appears tranquil, and shows passive behavior. After rescue, the patient is usually unconscious, flaccid, cold, and cyanotic. Respirations are absent, and the pulse is imperceptible. If the patient is conscious, tinnitus and visual abnormalities are often reported. Frothy fluid may be seen in the nose and mouth, and examination of the chest may disclose signs of pulmonary edema. If a significant amount of water has been swallowed, nausea and vomiting may occur, and gastric distention may be evident.
Electrocardiographic changes are often nonspecific, and they are related to myocardial anoxia. Cardiac arrhythmias such as atrial fibrillation and ventricular fibrillation, as reported for animals, are uncommon. Studies of gas in the blood may provide evidence of arterial hypoxemia and metabolic acidosis. Changes in serum electrolytes, on the other hand, may not appear significant. With appropriate therapy, there may be uneventful recovery. The post immersion period, however, may be complicated by pneumonia, hemoglobinuria, or nephrosis of the lower nephron. Occasionally, there may be brain damage from prolonged cerebral anoxia.
When the patient is a victim of near- drowning, other physical causes for disability should be considered. The diagnosis of near- drowning is usually not difficult after the circumstances are known. Diagnostic studies should include chest films, an electrocardiogram, serial determinations of gas in arterial blood, and appropriate laboratory tests, including determinations of hematocrit, hemoglobin, leukocytes, serum electrolytes, and serum protein.
When chest films show diffuse or nodular hazy opacification, the patient is febrile, and leukocytosis is evident during the post immersion period, respiratory complications, particularly pneumonia, are invariably present. In the differential diagnosis of near-drowning and drowning, other causes of aquatic accidents, especially air embolism and decompression sickness, must be considered. These untoward effects of barotrauma, discussed elsewhere, are usually associated with underwater swimming, diving, or the use of self-contained underwater breathing apparatus scuba). Recognition of barotrauma and differentiation from near-drowning are extremely important, for recompression, the appropriate method of treatment, may bring dramatic and life-saving results.
When the body of a dead person is found immersed in water, the diagnosis of drowning depends upon exclusion of other possible causes for death. Failure to find an injury or evidence of pre-existing disease, as well as the presence of evidence that the person was alive during the period of immersion, results in the presumption that death was caused by drowning. A careful appraisal of the circumstances of death and of findings from pathologic and toxicologic studies and from postmortem chemical and physical tests is required.
What Is Downing,First Aid Downing Treatment You Must Know
Survival depends upon the health of the victim, the duration of immersion, and the amount of water inhaled. Prompt rescue and first aid, including artificial resuscitation, offer the greatest chance for survival. The airway should be clear of any obstructions, and dentures should be removed prior to artificial resuscitation. If a heartbeat and carotid pulse are not detectable, closed-chest cardiac massage is required. Artificial resuscitation should be continued until spontaneous breathing occurs or signs of death are evident. In 1963 Naess reported recovery of a child who had drowned in a river. After resuscitation for two hours, heartbeat and spontaneous respirations were noted.
After the immediate period, further treatment should be carried out in either an intensive-care unit or a recovery room. If the patient survives the first 24 hours, it is likely that he may recover. Aspiration of the airway or tracheostomy may be necessary. Recurrent vomiting and aspiration of vomitus may be prevented by gastric decompression. Intermittent positive-pressure breathing of 100 per cent oxygen and administration of anti- foaming agents may be helpful. As the patient improves, oxygen may be administered by mask or catheter and reduced to 40 per cent in concentration.
Based upon serial determinations of gas in arterial blood, arterial hypoxemia and acid- base levels are corrected by effective ventilation, oxygenation, buffers, or bicarbonate. Steroids and antimicrobials are used for pneumonia. It may be necessary to use bronchodilators; digitalization; transfusions of whole blood, plasma, or packed red cells; hypothermia; or forced diuresis, as indicated.