DROWNING 

1️⃣ Definition & Terminology

📌 Current Standard Definition (WHO/ILCOR)

Drowning is a process resulting in primary respiratory impairment from submersion/immersion in a liquid medium.

 Terms like “near-drowning,” “dry drowning,” and “secondary drowning” are obsolete and discouraged.

2️⃣ Epidemiology

• One of the leading causes of accidental death globally
• Common in:
• Children <5 years
• Adolescents (risk-taking behavior)
• Alcohol-intoxicated adults
• Patients with seizures
• High incidence in low- and middle-income countries

3️⃣ Types of Drowning

A. Based on Water Type

📌 Exam point:
Despite theoretical differences, clinical management is identical.

B. Based on Mechanism

1️⃣ Aspiration Drowning (Majority)

• Water enters alveoli
• Surfactant washout
• Alveolar collapse
• ARDS-like picture

2️⃣ Laryngospasm (“Dry” type – rare concept)

• Reflex glottic closure
• Hypoxia without large-volume aspiration

3️⃣ Immersion Syndrome (Cold Shock)

• Sudden vagal arrest
• Arrhythmia before aspiration

4️⃣ Pathophysiology (Step-by-Step)

🔴 Stage 1 – Panic & Breath Holding

• Voluntary apnea
• Tachycardia
• Hypertension

🔴 Stage 2 – Aspiration

• Water enters airway
• Coughing
• Surfactant dilution
• Atelectasis

🔴 Stage 3 – Hypoxemia

• V/Q mismatch
• Shunt physiology
• Respiratory acidosis

🔴 Stage 4 – Cerebral Hypoxia

• Loss of consciousness
• Seizures
• Brain injury

🔴 Stage 5 – Cardiac Arrest

• Initially tachyarrhythmias
• Then bradycardia
• PEA/asystole

5️⃣ Pulmonary Pathology

Findings:

• Diffuse alveolar damage
• Surfactant inactivation
• Capillary leak
• Non-cardiogenic pulmonary edema
• ARDS pattern

6️⃣ Clinical Presentation

Mild

• Cough
• Tachypnea
• Mild hypoxemia

Moderate

• Respiratory distress
• Crackles
• Hypoxia
• Agitation

Severe

• Cyanosis
• Coma
• Hypotension
• Cardiac arrest

7️⃣ Initial Assessment (ABCDE Approach)

🅰 Airway

• Clear debris
• Suction
• Early intubation if:
• GCS ≤ 8
• Severe hypoxia
• Respiratory fatigue

🅱 Breathing

• 100% oxygen
• ABG
• Chest X-ray

🅲 Circulation

• CPR if arrest
• Warm IV fluids
• Vasopressors if shock

🅳 Disability

• GCS
• Pupils
• Seizures

🅴 Exposure

• Hypothermia
• Trauma
• Cervical spine precautions

8️⃣ Management in Detail

 1. Immediate Resuscitation

CPR

• Follow standard ACLS
• Hypoxia-driven arrest → prioritize ventilation
• Defibrillate if indicated

Airway Strategy

• RSI with cervical protection
• PEEP after intubation

 2. Ventilation Strategy

Treat as ARDS:

• Low tidal volume (6 mL/kg PBW)
• Plateau pressure < 30 cmH₂O
• High PEEP strategy
• Prone positioning if PaO₂/FiO₂ <150
• Neuromuscular blockade (early severe ARDS)

 3. Fluid Management

• Balanced crystalloids
• Avoid fluid overload
• Conservative strategy after stabilization

 4. Hypothermia Management

Types:

• Mild: 32–35°C
• Moderate: 28–32°C
• Severe: <28°C

Key Principle:

“No one is dead until warm and dead”

• Rewarm gradually
• Warm IV fluids
• Forced air warming
• ECMO in refractory cases

 5. Antibiotics?

• NOT routine
• Indicated if:
• Gross contamination
• Sewage exposure
• Signs of pneumonia after 24–48 h

Common organisms:

• Aeromonas
• Pseudomonas

 6. Steroids— No proven benefit,Not recommended routinely

 7. Surfactant Therapy—Not standard; limited evidence

 8. Neuroprotection

• Maintain normoxia
• Maintain normocapnia
• Avoid hyperthermia
• Control seizures
• Avoid hypotension

Targeted temperature management:

• Consider in post-arrest patients

9️⃣ Complications

Early

• ARDS
• Hypoxic brain injury
• Shock
• Metabolic acidosis

Late

• Pneumonia
• Bronchiectasis (rare)
• Persistent vegetative state

🔟 Prognostic Factors

Poor Prognostic Indicators:

• Submersion >10 min
• CPR >25 min
• Asystole at presentation
• Severe metabolic acidosis (pH <7)
• Fixed dilated pupils

Favorable Factors:

• Cold water (protective hypothermia)
• Rapid rescue
• Immediate CPR

1️⃣3️⃣ Radiological Evolution

CXR may initially be normal.

Within 4–6 hours:

• Bilateral infiltrates
• ARDS pattern

1️⃣4️⃣ Disposition

Observe 6–8 hours if:

• Normal oxygenation
• Asymptomatic

ICU admission if:

• Hypoxia
• Altered sensorium
• Respiratory distress

1️⃣5️⃣ Prevention Strategies

• Swimming education
• Life jackets
• Alcohol avoidance
• Pool fencing
• Supervision of children