Pediatric Drowning

This is a summarized version of the full in-depth article on Relias Media.

AUTHOR

Daniel Migliaccio, MD, Clinical Assistant Professor, Ultrasound Fellowship Director, Department of Emergency Medicine, University of North Carolina, Chapel Hill, Vice President, AAEM Young Physician Section

PEER REVIEWER

Aaron Leetch, MD, FACEP, Associate Professor, Director, Combined EM and Peds Residency, University of Arizona College of Medicine, Tucson

Introduction

Drowning is defined as the process of experiencing respiratory difficulty or arrest due to submersion or immersion in a liquid. Historically, inconsistent terminology has led to confusion in the medical community. To standardize drowning definitions, the World Health Organization (WHO) now classifies drowning into three categories: drowning with death, drowning with morbidity, and drowning without morbidity. Outdated terms like "near drowning" and "dry drowning" are no longer recommended. While most submersion injuries do not result in death, drowning can lead to a wide spectrum of outcomes, including minor respiratory symptoms or profound long-term neurological disability. Emergency providers must be well-versed in the pathophysiology, presentation, and management of drowning incidents to optimize outcomes.

Epidemiology

Globally, drowning accounts for more than 370,000 deaths annually, though some estimates suggest that as many as 40%-50% of drowning deaths go unreported, often categorized as "water transport incidents." Drowning disproportionately affects low- and middle-income countries, which contribute to over 90% of drowning fatalities worldwide. Drowning is a leading cause of death among individuals aged 1-24 years, and in the United States, there are over 500,000 drowning incidents annually, resulting in more than 1,100 deaths.

Children younger than 5 years and adolescents aged 15-24 years have the highest rates of drowning, with more than 50% of all drowning deaths occurring in individuals younger than 25 years. Socioeconomic factors play a role, as drowning rates are higher among African-Americans, children from southeastern states, and those from low-income households. Drowning is most common in males, who are twice as likely to drown as females.

Risk Factors

Several factors increase the risk of drowning:

• Children under 5 years: Lack of supervision, behavioral disorders, and undetected seizure or dysrhythmic disorders.

• Older children and adolescents: Lack of water safety practices, misjudgment of swimming skills, and risk-taking behaviors.

• Alcohol and drug use: Particularly among adolescents and young adults, inappropriate use of substances is a significant drowning risk.

Pathophysiology

Drowning begins when the airways are submerged, triggering the diving reflex, a parasympathetic response causing bradycardia, peripheral vasoconstriction, and central shunting of blood. However, this reflex is quickly overwhelmed by the sympathetic nervous system, leading to disorganized breathing, breath-holding, and, eventually, aspiration of water.

Water aspiration dilutes surfactant in the lungs, resulting in alveolar collapse, decreased lung compliance, and noncardiogenic pulmonary edema. Ventilation/perfusion mismatch and intrapulmonary shunting cause hypoxemia. Importantly, the type of water (salt or fresh) aspirated is clinically irrelevant in most nonfatal cases, as large volumes (11-22 mL/kg) are required to produce significant electrolyte shifts, which are rarely aspirated in drowning survivors.

Additionally, laryngospasm may occur, worsening hypoxia. This reflexive closure of the airway was once thought to explain "dry drowning," a now-discredited term based on the absence of fluid in the lungs during autopsy. In reality, drowning deaths always involve some fluid in the airways.

Clinical Presentation

The clinical effects of drowning primarily result from hypoxemia. Respiratory symptoms range from shortness of breath to cough, and physical findings may include tachypnea, accessory muscle use, and rales. Neurologically, hypoxemia can lead to cerebral edema, increased intracranial pressure, and hypoxic-ischemic brain injury, with 20% of nonfatal drowning victims suffering long-term neurological damage.

Cardiac dysrhythmias, such as atrial fibrillation, ventricular tachycardia, and sinus bradycardia, may occur due to hypoxemia or hypothermia. In severe cases, renal injury, typically acute tubular necrosis, can occur due to hypoxia. Life-threatening electrolyte disturbances are rare but may develop from renal damage.

Diagnostic Studies

• Chest X-ray: Useful for evaluating pulmonary aspiration or hypoxia-related end-organ damage. Findings may include patchy opacities or pulmonary edema, though imaging may be normal initially.

• Laboratory tests: In symptomatic patients, labs are used to assess for acidosis or renal dysfunction. Asymptomatic patients do not require labs, as they are not predictive of complications.

• Neuroimaging: For significant mental status changes, CT or delayed MRI may help assess brain injury.

• Point-of-care ultrasound (POCUS): Can help monitor pulmonary edema, as seen with B lines on lung ultrasound, indicating fluid in the alveoli.

Initial Management

Management begins with pre-hospital resuscitation according to basic life support protocols. On arrival to the emergency department (ED), the following steps are crucial:

1. Airway management: Symptomatic patients require continuous oxygen saturation monitoring and supplemental oxygen. Noninvasive positive pressure ventilation (NIPPV), such as CPAP or BiPAP, can improve oxygenation by increasing positive end-expiratory pressure (PEEP).

1. Endotracheal intubation: Indicated for patients with severe hypoxia (PaO2 < 60 mmHg in adults, < 80 mmHg in children) or neurological deterioration.

1. Monitoring: Continuous cardiac telemetry and end-tidal CO2 monitoring should be employed.

1. Trauma evaluation: If trauma is suspected, manage according to ATLS guidelines.

Hypothermia Management

Hypothermic drowning victims should be rewarmed using passive or active methods (e.g., warm IV fluids, warm air blankets). Severe hypothermia (<28°C) requires aggressive rewarming techniques, and extracorporeal membrane oxygenation (ECMO) may be considered in severe cases. Hypothermia afterdrop, a continued cooling effect after removal from cold water, should not alter rewarming efforts. Cold diuresis, which can cause hypovolemia and hypotension, may require fluid resuscitation.

Post-Resuscitation Management

Symptomatic patients or those requiring cardiopulmonary resuscitation should be admitted to the ICU for monitoring. Supportive care includes positive pressure ventilation for those with pulmonary symptoms and pressors for patients who experienced cardiopulmonary arrest. The routine use of antibiotics is not recommended unless there is evidence of infection, and steroids do not improve outcomes.

Admission and Discharge Criteria

Patients who present with normal mental status, oxygen saturation above 95%, and no respiratory symptoms can be observed in the ED for 6-8 hours and discharged if they remain stable. Indications for hospital admission include:

• Prolonged submersion (>5-15 minutes)

• Glasgow Coma Scale <13

• Hypoxia or abnormal respiratory exam findings

• Abnormal chest imaging or lab results

• Persistent symptoms (e.g., shortness of breath, cough)

Prognosis

The prognosis for drowning victims depends on the severity and duration of hypoxia. Most asymptomatic patients or those who recover quickly after submersion have minimal to no long-term disability. In contrast, victims requiring CPR or presenting with severe hypoxia have a higher likelihood of long-term neurological damage or death. Prognostic indicators for poor outcomes include prolonged submersion, delayed resuscitation, severe acidosis, and Glasgow Coma Scale <5.

Prevention

Drowning is highly preventable. Strategies include securing pools with fencing, close supervision of children near water, and education about water safety. Organizations like the American Academy of Pediatrics (AAP), the World Health Organization (WHO), and the Centers for Disease Control and Prevention (CDC) provide resources to guide drowning prevention efforts.

Conclusion

Drowning remains a significant cause of morbidity and mortality worldwide, particularly in children and adolescents. Emergency providers must be equipped to manage drowning victims with a focus on preventing and treating hypoxia-related complications. Prompt and aggressive resuscitation, particularly in pediatric patients, is crucial for improving outcomes. Prevention efforts are key in reducing the global burden of drowning.

Read the full in-depth article on Relias Media

We discuss pediatric drowning in more detail and include detailed charts and tables in our full write-up on Relias Media.

Read Full Article