Drowning is a complex of pathological changes in the work of vital systems that occurs when completely immersed in water and, in the absence of timely assistance, leads to the death of the patient. The main symptoms are tachycardia, hypertension, bloating and foam discharge from the respiratory openings. The skin is bluish, cold, pupillary reflexes are weakly expressed. During clinical death, there is no breathing, consciousness and pulsation on the central arteries. Pathology is diagnosed on the basis of anamnesis and appearance of the patient. Specific treatment: removal of H2O, ventilation, warming, infusion solutions, benzodiazepines, diuretics and hormones in the development of pulmonary edema.
General information
Drowning (aspiration, hydrogenic asphyxia) — death as a result of complete immersion in water. Death in other environments (oils, gasoline, barrels with alcoholic beverages), when only the nose and mouth are covered with water, drowning is not considered. Every year about 450 thousand people die in the reservoirs of the world. 54% of the victims are people aged 20-30 years, 40% are teenagers. In the USA, over the past 5 years, there have been 63 thousand deaths on the water, 14 thousand of them are children under the age of 15. A significant part of the deceased could swim or just stay on the surface. The absolute majority of cases are registered in the spring-summer period, when the population actively swims in open ponds and lakes. The attendance of the recreation area practically does not matter. It is difficult to notice a drowning person, because his behavior usually does not correspond to the ideas of most vacationers.
Causes
Death in the water can occur for a variety of reasons. About half of the cases among adults and adolescents aged 14-18 years are associated with heavy alcohol intoxication. A person who is under the influence of alcohol has poor control of the environment, has unregulated motor skills, is unable to quickly assess the events taking place and take the measures necessary for his own salvation. Other circumstances in which drowning occurs include:
- Fear. The leading factor of death in accidents of ships and boats, the fall of an airplane into the sea. The resulting panic makes a person’s movements uncoordinated. He cannot understand what needs to be done to survive (to find a watercraft, to move as far as possible from the ship in distress). Hasty and frequent movements lead to a rapid depletion of physical resources, the victim gets tired, is unable to continue resistance, plunges into the water and takes an involuntary breath, which is accompanied by aspiration.
- Hypothermia. The faster it comes, the lower the temperature the water has. The duration of being in the reservoir at a temperature of 24 ° C reaches 8 hours, 20 ° C — 2.5 hours, 15 ° C — 1 hour, 4 ° C — 10-20 minutes. Then there is a depression of consciousness, a weakening of the ability to move, hemodynamic disorders caused by spasm of peripheral and central vessels. In such conditions, no more than half of the victims survive. A person who is in the open sea and has no means of salvation almost always dies.
- Cardiac arrest. It usually develops due to a sharp temperature fluctuation when diving into cold water. Cases of sudden cardiac death are noted during Epiphany bathing in an ice hole, visiting a recreation area in the autumn or early spring, when the difference between the temperature of air and water in open reservoirs is great. Sometimes asystole occurs for reasons unrelated to immersion: coronary disease, sudden thrombosis, AMI. Laryngocardial reflex can provoke a stop of blood circulation when liquid enters the URT.
- Muscle spasms. Drowning due to skeletal muscle spasm occurs in inexperienced swimmers. The exclusion of even one of the limbs from work does not allow them to continue swimming and return safely to shore. The situation is aggravated by panic and discoordination of movements. People who are confident on the water and have the necessary skills are able to save themselves in such situations.
- Injuries. They usually occur when bathing in unfamiliar places. The mechanism is a head impact on the bottom, accompanied by loss of consciousness or fracture of the cervical vertebrae, followed by paralysis. In such situations, a person takes an involuntary sigh or loses the ability to move, which does not allow him to float to the surface. Hydrogenic asphyxia of this type is a phenomenon common among children and adolescents who are not aware of the danger they are exposed to when jumping into the lake upside down.
Pathogenesis
The pathogenesis directly depends on the type of drowning. With the aspiration type of condition, the lungs are filled with water. An adult can inhale up to 4 liters. The liquid forms a foamy gray-white mass that fills the lumen of the bronchi and alveoli. Emphysema develops, there is a rupture of the walls of the respiratory vesicles, water penetrates into the blood, causing hemolysis of red blood cells, violation of salt balance, cardiac fibrillation, acute heart failure. The duration of the process is 5-6 minutes. With the asphyxic variety, the victim has acute oxygen starvation. This becomes possible due to persistent spasm of the vocal cords that have been irritated. There is no aspiration of the liquid. There is acute hyperaeration of lung tissue, alveolar damage, respiratory failure, hypoxia. Possible air embolism of the heart.
Syncopal drowning occurs with a rapid reflex cessation of respiratory and cardiac activity. Spasm of the pulmonary and superficial vessels, prolonged contraction of the respiratory muscles, fainting, anemia and ischemia of the tissues of the central nervous system are determined. With a mixed type, all the described features are combined. The process begins with laryngospasm, which subsequently disappears, opening the way to water. The liquid penetrates into the lung sacs, foams. A pathoanatomic sign of any of the varieties is considered to be serous edema of the walls of the gallbladder, liver and hepatoduodenal ligament. This is due to the acute deposition of blood in the structure of hepatic capillaries.
Classification
Drowning is classified by stages of development and pathogenetic mechanisms. In the first case, the initial and agonal stages are distinguished, followed by clinical death. The first stage is characterized by the preservation of consciousness, instability of blood circulation, a decrease in the level of blood oxygenation, the consequences of psychological stress, chills. In the agonal period, there is a sharp respiratory depression, a violation of cardiac activity and a change in homeostasis, marked respiratory failure. Clinical death is manifested by respiratory and circulatory arrest, lack of consciousness and reflexes. Death may have the following mechanisms of development:
- True (wet). Accounts for 80% of all cases. It is accompanied by the ingress of water into the bronchi and lungs, foaming. The main feature is pronounced cyanosis of the skin. Develops when trying to inhale during immersion. It is most often a factor in the death of the victim. It is divided into drowning in freshwater and saltwater reservoirs. The ingress of fluid with a high NaCl content into the alveoli causes pulmonal edema that occurs a few hours after successful resuscitation. Fresh water does not cause such an effect.
- Asphyxiating. This variant accounts for 10-15% of situations associated with hydrogenic asphyxia. At the same time, the liquid does not penetrate into the lungs, but provokes reflex laryngospasm, irritates the receptors of the vocal cords. A large volume of water is swallowed into the stomach. Diffuse cyanosis is expressed to the same extent as in the wet variety.
- Syncopal. It is the result of reflex cardiac arrest due to a significant temperature drop (ice shock, immersion syndrome). A similar reaction may occur when water enters the middle ear against the background of a damaged eardrum. Loss of consciousness with subsequent death is sometimes found in paroxysms of arrhythmia, epilepsy and critical conditions of other etiology. The main difference is the pallor of the skin due to a pronounced spasm of the peripheral vascular network. Diffuse cyanosis is not observed. Foamy discharge is absent, the victim’s mouth and nose are free.
Symptoms
The clinical picture depends on the period of injury. At first, the victim retains consciousness and voluntary movements, psychological arousal or inhibition is detected, inappropriate behavior is possible. The skin and mucous membranes are bluish in color, breathing is noisy, rapid, interrupted by coughing. Tachycardia and hypertension are noted, but soon the picture may change up to the opposite (decrease in blood pressure, heart rate). The epigastrium is swollen due to water entering the stomach, vomiting is observed. Acute symptoms disappear relatively quickly. Cephalgia, cough and weakness may persist for several days.
The agonal stage is accompanied by the development of unconsciousness, but cardiac and respiratory activity does not completely stop. The skin is sharply bluish, cold, there is a foamy pinkish discharge from the nose (with a reflex type, this sign is not detected). The pulse is irregular, rare, determined only on the femoral and carotid arteries. Due to vasospasm, thrusts on the radial artery are not palpable. The subcutaneous veins of the neck are dilated, swollen. Corneal and pupillary reflexes disappear, a trism of the masticatory muscles develops. The appearance of the patient at clinical death does not change. The pulse cannot be felt on the central vessels. Pupils are dilated, there is no reaction to light and pain sensitivity. Breathing stops, consciousness is absent.
Complications
A common complication is edema of the lungs and brain. It occurs in 95-100% of cases of marine disasters and in 30-35% of cases of drowning in fresh water. When exposed to a salty liquid, the phenomenon is caused by the difference in osmotic pressure of internal media and a foreign agent. The penetration of water with a low sodium chloride content into the lungs provokes tissue hyperhydration by a significant increase in CBV and changes in homeostasis.
With prolonged respiratory arrest, posthypoxic encephalopathy is possible. It develops due to the death of brain cells that are in conditions of severe hypoxia for more than 4-5 minutes. It is manifested by disorders of the regulation of internal organs and skeletal muscles, weakening of mental abilities and inappropriate behavior. A longer period of apnea triggers the mechanism of irreversible changes up to decortication (brain death). Drowning in cold water increases the period during which irreversible changes in the central nervous system do not occur.
Diagnostics
The diagnosis of drowning is made directly on the shore by people who provide first aid. Most often, these are members of the SMP brigade or medical workers present at the scene of the incident. The grounds are the clinical picture and anamnesis of the patient. The stories of eyewitnesses and relatives of the victim have a certain significance. Other types of examination are used in the hospital to determine the consequences of injury. The following types of research may be required:
- Laboratory. There are electrolyte disturbances in the blood, an increase in the concentration of salts. This is especially noticeable in the example of sodium chloride when seawater enters the body. The pH of the blood usually shifts to the acidic side with prolonged apnea, alkalosis can occur against the background of resuscitation with the introduction of a large volume of sodium bicarbonate. There is an increase in the pCO2 index above 50 mmHg.
- Instrumental. If severe hypoxic brain damage is suspected, electroencephalography is indicated. If the doctor’s assumptions are correct, the study reveals a decrease in the activity of the beta rhythm, an increase in the delta amplitude. Radiography in direct and lateral projection is used to determine pulmonary edema. Pathology is manifested by a decrease in the transparency of the fields, vague focal shadows merging with each other.
Emergency care
After removing the victim from the water, it is necessary to assess his condition, determine the type of pathology. Removal of water from the lungs is indicated only with its presumably large volume. In 90% of situations, the amount of liquid does not exceed 200-300 ml, which are quickly absorbed into the bloodstream and practically do not pose a danger. The initial period is an indication for short—term oxygen insufflation through nasal cannulas or a facial mask. In the absence of the necessary equipment, mouth-to-mouth breathing is carried out. Infusions of soda, hydroxyethyl starch, glucose are required. With psychomotor agitation, benzodiazepines are used. It is possible to introduce ascorbic acid, vitamin E, antioxidants.
In case of agony, tracheal intubation, short-term ventilation with 100% oxygen is recommended. After 3-5 minutes, the concentration of O2 in the mixture should be reduced to 30-35%. Pharmacological support does not differ from the one described above. In hypotension, stimulants (caffeine, cordiamine) and cardiotonics (dopamine, dobutamine) are administered. Clinical death is an indication for the beginning of resuscitation measures using triple Safar and indirect heart massage. Medication for CPR outside the hospital includes epinephrine, in ICU departments — epinephrine, atropine, calcium chloride and sodium bicarbonate. Correction of electrolyte changes at any stage is carried out by volumetric infusion of crystalloid fluids.
Prognosis and prevention
In general, drowning has a favorable prognosis, but it must be borne in mind that severe complications resulting in the death of the patient can develop up to 24 hours from the moment a person is removed from the water. The main cause of delayed death is severe pulmonary edema, respiratory distress syndrome. It is permissible to talk about a successful outcome no earlier than a day after hospitalization. The risk increases with being under water for more than 25 minutes, the development of coma, “wet” type of pathology, cardiopulmonary resuscitation in the anamnesis (regardless of its time).
To prevent drowning, it is necessary to carefully monitor relatives and friends on beaches and in recreation areas. Special attention is required by children, the elderly and people who are intoxicated. After drinking alcohol, staying in the water is strictly prohibited. Vacationers who do not know how to swim should stay in lakes and rivers only in a life jacket, having watercraft in the form of circles, mattresses and inflatable boats. It is forbidden to swim outside the designated bathing area marked with buoys. Before diving into the ice hole, you should stand naked in the cold air for a few minutes so that the body has time to adapt to low temperatures. You need to enter the font gradually.
