Drowning (Near Drowning) Flashcards
What is the pathophysiology of drowning?
Drowning is a leading cause of accidental death in the United States. It occurs when a person suffers primary respiratory impairment from submersion or immersion in a liquid medium (usually water). The drowning process is considered a continuum with outcomes that range from survival to death.
What points should be taught to the patient regarding preventing/ avoiding drowning accidents?
- Constantly observe people who cannot swim and are in or around water.
- Do not swim alone.
- Test the water depth before diving in head first; never dive into shallow water.
- Avoid alcoholic beverages and substance use when swimming and boating and while in proximity to water.
- Ensure that water rescue equipment such as life jackets, flotation devices, and rope is immediately available when around water.
What should be assessed/ expected signs and symptoms of the patient?
- When water is aspirated into the lungs, the quantity and makeup of the water are key factors in the pathophysiology of the drowning event. Aspiration of both fresh water and salt water causes surfactant to wash out of the lungs. Surfactant reduces surface tension within the alveoli, increases lung compliance and alveolar radius, and decreases the work of breathing. Loss of surfactant destabilizes the alveoli and leads to increased airway resistance. Salt water—a hypertonic fluid—also creates an osmotic gradient that draws protein-rich fluid from the vascular space into the alveoli. In both cases, pulmonary edema results. Salt water and fresh water aspiration cause similar degrees of lung injury. Another concern is water quality; the victim’s outcome may be negatively affected by contaminants in the water such as chemicals, algae, microbes, sand, and mud. These substances can worsen lung injury and cause infection.
- The duration and severity of hypoxia are the two most important factors that determine outcomes for victims of drowning. Very cold water seems to have a protective effect. Successful resuscitations have been reported even after prolonged arrest intervals. Hypothermia might offer some protection to the hypoxic brain by reducing the cerebral metabolic rate. The diving reflex is a physiologic response to asphyxia, which produces bradycardia; a reduction in cardiac output; and vasoconstriction of vessels in the intestine, skeletal muscles, and kidneys. These physiologic effects are thought to reduce myocardial oxygen use and enhance blood flow to the heart and cerebral tissues. Survival is thought to be linked to some combination of the effects of hypothermia and the diving reflex.
- The cause of the drowning should also be determined if possible. The patient may have experienced an event that caused the drowning event such as a seizure, myocardial infarction, brain attack, or spinal cord injury while in the water. Injuries sustained from diving into shallow water or body surfing, such as cervical spine trauma, can also increase the difficulty of rescue and resuscitation efforts.
What interventions are included in the prehospital care?
Potential rescuers must consider their own swimming abilities and limitations and any natural or human-made hazards before attempting to save the victim; failure to do so could place additional lives in jeopardy. Once rescuers gain access to the victim, the priority is safe removal from the water. Spine stabilization with a board or flotation device should be considered only for victims who are at high risk for spine trauma (e.g., history of diving, use of a water slide, signs of injury or alcohol intoxication), as opposed to all drowning victims. Time is critical; efforts directed toward a rapid rescue have the most potential benefit. Initiate airway clearance and ventilatory support measures, including delivering rescue breaths, as soon as possible while the patient is still in the water. If hypothermia is a concern, handle the victim gently to prevent ventricular fibrillation.
What interventions are included in hospital care?
Once the person is safely removed from the water, airway and cardiopulmonary support interventions begin, including oxygen administration, endotracheal intubation, CPR, and defibrillation, if necessary. In the clinical setting, gastric decompression with a nasogastric or orogastric tube is needed to prevent aspiration of gastric contents and improve ventilatory function. After a period of artificial ventilation by mask, the patient typically has a distended abdomen, which impairs movement of the diaphragm and decreases lung ventilation. Patients who experience drowning require complex care. The full spectrum of critical care technology may be needed to manage the pathophysiologic complications of drowning, including pulmonary edema, infection, acute respiratory distress syndrome (ARDS), and CNS impairment.
What is a critical rescue point to keep in mind?
Recognize that you must not attempt to get the water out of the victim’s lungs; respond by delivering abdominal or chest thrusts only if airway obstruction is suspected.
