Chapter 22 Drowning and Near-Drowning
PATHOPHYSIOLOGY
Each year, between 4000 and 5000 people drown in the United States, and the number of near-drownings is estimated to be 3 to 4 times that figure. Drowning is defined as death from asphyxia while submerged, or within 24 hours of submersion. Near-drowning occurs when the child survives longer than 24 hours after submersion, regardless of the final outcome.
The physiologic events that occur after submersion are sequential. After the initial panic and struggle, victims will hold their breath, and some will swallow a small amount of water, vomit, then aspirate the vomitus. Laryngospasm follows, which leads to hypoxia and death (dry drowning). In most children laryngospasm occurs initially; this leads to hypoxia, which causes cardiac arrest and relaxation of the airway, so that the lungs are permitted to fill with large amounts of water (wet drowning). Regardless of whether the child aspirates water, hypoxia is the most important physiologic consequence of submersion injuries and affects all organ systems. Submersion also results in hypothermia. The child’s relatively large body surface area leads to a rapid decrease in body temperature when the child is in cold water. Severe hypothermia in young children may protect the brain when the diving reflex occurs, causing bradycardia and shunting of blood away from the periphery and thereby increasing the cerebral and coronary circulation.
Prognosis is affected by a variety of factors, such as duration of submersion, extent of hypothermia, physiologic response of the victim, and length of time until effective cardiopulmonary resuscitation is provided. Irreversible brain damage usually occurs after 4 to 6 minutes of submersion, but some children have experienced complete recovery after a much longer period (10 to 30 minutes) in very cold water. Morbidity and death are directly related to the degree of neuronal damage.
INCIDENCE
1. Drowning is the second leading cause of accidental death in children.
2. Preschool children and teenagers have the highest risk for drowning and near-drowning.
3. Boys are 5 times more likely to drown than girls.
4. Peak incidence is during summer months, on weekends, and between 4 pm and 6 pm.
5. Most drownings occur in residential swimming pools.
6. Younger children most often drown in pools, bathtubs, hot tubs, toilets, and buckets.
7. Older children most often drown in lakes, rivers, and oceans while boating or diving, or in association with alcohol ingestion.
CLINICAL MANIFESTATIONS
Clinical manifestations are directly related to the extent of injury and level of consciousness following rescue and resuscitation.
LABORATORY AND DIAGNOSTIC TESTS
1. Chest radiographic study—variable findings (from scattered parenchymal infiltrates to extensive pulmonary edema)
2. Arterial blood gas values—to detect respiratory and metabolic acidosis
3. Electroencephalogram—to assess seizure activity and document brain death
4. Complete blood count, hematocrit, hemoglobin—to determine extent of hemodilution or hemoconcentration and need for fluid resuscitation
5. Serum electrolyte levels—to determine need to correct any imbalances caused by submersion
6. Blood urea nitrogen level—to determine renal function
7. Creatinine clearance—to determine renal function
8. Blood culture and sensitivity—to detect superimposed respiratory infection
MEDICAL MANAGEMENT
Aggressive basic and advanced life support at the scene is essential, because the full extent of the central nervous system injury cannot be accurately assessed at the time of rescue. Ensuring an adequate airway, breathing, and circulation is the top priority. Other injuries must be considered, and the need for hospitalization is determined by the severity of the event and clinical evaluation. Individuals with respiratory symptoms, decreased oxygen saturation, and altered level of consciousness must be admitted to the hospital. Ongoing attention to oxygenation, ventilation, and cardiac function is the priority. Protecting the central nervous system and reducing cerebral edema are of paramount importance and directly relate to outcome.
Treatments used include high-flow oxygen therapy and positive end-expiratory pressure for adequate oxygenation; administration of crystalloid solution for fluid resuscitation; dopamine and dobutamine for cardiac therapy; furosemide (Lasix) for diuresis; and mannitol (Mannitor) for control of intracranial hypertension and for sedation.
NURSING INTERVENTIONS
1. Monitor respiratory system.
2. Monitor cardiovascular system.
3. Monitor and record child’s level of neurologic functioning.
4. Monitor and maintain fluid balance.
5. Monitor and maintain homeostatic temperature regulation.
6. Provide and maintain adequate nutritional intake.
Discharge Planning and Home Care
1. Instruct parents about instituting preventive measures: learning cardiopulmonary resuscitation; providing water safety and swimming lessons for child; accident-proofing backyard (e.g., pool cover, fence enclosures); and appropriately supervising children during pool use.
2. Instruct parents regarding developmental level of child and safety issues.
Behrman RE, Kiegman R, Jenson HB. Nelson textbook of pediatrics, ed 17, Philadelphia: WB Saunders, 2004.
Burford A, et al. Drowning and near-drowning in children and adolescents: A succinct review for emergency physicians and nurses. Pediatr Emerg Care. 2005;21(9):610.
Hockenberry M, et al. Wong’s nursing care of infants and children, ed 7. St. Louis: Mosby, 2004.
Lassman J. Injury prevention. Water safety, J Emerg Nurs. 2002;28(3):241.
