Drowning is defined as a process of experiencing respiratory impairment from submersion/immersion in a liquid medium. To delineate the incident’s outcome, this is further divided into descriptive terms such as death, morbidity, and no morbidity. Wet drowning, dry drowning, and near-drowning are no longer accepted terms, although they may still be used when discussing drowning.

Drowning is a major public health problem, especially in children. Drowning usually occurs in a rapid fashion and is most often silent. Individuals who thrash wildy in water while drowning are rare. In most cases, a motionless individual floating in water who rapidly disappears beneath the surface is the classic scenario.

Drowning can occur in both warm and cold water. In many cases, cold water can be protective especially in children. The most immediate threat in drowning is dysfunction of the cardiac and CNS systems. Hypoxemia and acidosis need to be corrected immediately if mortality is to be avoided. Even those who survive may develop a vegetative state due to the prolonged cerebral hypoxia.

Etiology

Accidental or deliberate exposure to submersion in water or other liquid substances that inhibit the body’s ability to oxygenate tissues and organs.

Risk factors for drowning include:

• Head trauma
• Seizure
• Cardiac arrhythmia
• Hypoglycemia
• Hypothermia
• Alcohol and drug use
• Suicide
• Panic attack
• Myocardial infarction
• Depression
• Poor judgment
• Scuba diving
• Natural disaster

In infants, the cause is often accidental and may occur in the bathtub or even the bathing pail. Most infant deaths occur within 5 minutes of a lapse in supervision. Older children tend to drown in the swimming pool. Often the gate or the fence to the pool is open and the child just jumps in. Adults tend to drown in lakes, rivers, and the sea. In many adult cases of drowning, there may be an associated injury, like diving in shallow waters and hitting a rock.

Worldwide, drowning accounts for an estimated 360, 000 deaths annually. This represents 7% of all injury-related fatalities and is the leading cause of death among young males. It is estimated that 4, 000 fatalities occur each year in the United States. Furthermore, it is estimated that for every fatal drowning, four non-fatal drowning victims seek medical care. Fifty percent of those patients require hospital admission and interventions. There are three age-related peaks of victims which include small children (younger than 5), adolescents, and the elderly. Patients may drown in bathtubs, pools, large bodies of water or even rain-filled buckets in the yard. Risk factors for drowning include children and teenagers, residents of southern states, occurring during summer months, concomitant drug or alcohol use, and associated medical problems including dysrhythmias or epilepsy.

When a person suffers from submersion or immersion in a liquid medium, vital tissues may become hypoxic and acidotic which may result in cardiac dysrhythmias (progressing from tachycardia, bradycardia, pulseless electrical activity, and asystole). Aspirated fluid can lead to surfactant washout and dysfunction, increased permeability of the alveolar-capillary membrane, decreased lung compliance, and ventilation/perfusion ratio mismatching. This can result from minor to no respiratory complaints to fulminant non-cardiogenic pulmonary edema, with a clinical picture similar to adult or acute respiratory distress syndrome (ARDS).

The highest morbidity and mortality are related to cerebral hypoxia, and management is aimed at reversing hypoxia as quickly as possible. Interestingly, hypothermic exposure with the incident may be tissue-protective, although may result in an increased occurrence of cardiac dysrhythmias.

Determination of the toxicity of the water that the victim was immersed in (eg saltwater versus freshwater) is of little importance in non-fatal drowning. Volume or serum (electrolyte) changes only occur when a significant volume of fluid is aspirated. It is more important to note if the fluid was obviously contaminated (sewage), as those patients are highly prone to pulmonary infection and prophylactic antibiotics may be warranted at presentation. Additionally, current recommendations state that routine use of cervical spine immobilization and imaging is not warranted unless the history or exam suggests that the patient suffered from a traumatic injury.

At least 20% of individuals develop tight laryngospasm that lasts even after cardiac arrest. These victims seldom aspirate any fluid and are said to have dry drowning.

History and Physical

Someone who is drowning or nearly drowning usually has a history of struggling to breathe after an extended period of water submersion. The skin may appear blue or pale from lack of oxygen in the blood. The patient may be in respiratory distress with apnea or shallow breathing, have an altered level of consciousness, be coughing, fatigued, or have other neurological findings.

Prognosis

Only patients who are alert or mildly confused at the initial presentation have a good prognosis. Victims who are comatose usually fair poorly. Those who are comatose and resuscitated with CPR often develop severe brain injury and hypoxic encephalopathy. At least 10-30% of children with brain damage require long term rehabilitation. Hypothermia can protect the brain in some children. Other risks of drowning include aspiration, ARDS, and death.

Treatment / Management

The greatest morbidity and mortality associated with non-fatal drowning is due to tissue hypoxia, specifically cerebral hypoxia, and thus, the greatest priority in the resuscitation process is to address and correct hypoxia quickly. Hypothermic patients should have their pulse assessed for 30 seconds, as their pulse may be weak, and starting CPR on a heart that has an organized rhythm may trigger life-threatening dysrhythmia. When examining, manipulating, and moving hypothermic patients, it is important to be gentle to prevent inciting a dysrhythmia. Passive and active rewarming methods should be employed to warm the patient’s core temperature.

Initial management of the patient includes delivering oxygen non-rebreather or non-invasive positive pressure ventilation. Oxygen should be titrated to maintain oxygen saturation between 92% – 96% and to avoid over oxygenation.  Nebulized albuterol may be given for bronchospasm. Cardiac support should be employed.

Patients with mild to no symptoms may be observed in the emergency department for four to eight hours, and if they continue to do well, they may be discharged home with return precautions given. Symptomatic patients may warrant further observation with inpatient admission to the appropriate area (floor vs. intensive care depending on the severity of their symptoms).

According To The American Heart Association

Rescuers should provide CPR, including rescue breathing, as soon as an unresponsive submersion victim is removed from the water. All victims of drowning who require any form of resuscitation (including rescue breathing alone) should be transported to the hospital for evaluation and monitoring, even if they appear to be alert and demonstrate effective cardiorespiratory function at the scene. Routine stabilization of the cervical spine in the absence of circumstances that suggest a spinal injury is not recommended.