Wk 12 PPT Near Drowning (1)

NEAR DROWNING

  • Sources: Des jardins ch 42, Egan's ch 30

TERMINOLOGY

Drowning

  • Definition: Respiratory impairment due to submersion or immersion in liquid.

  • Outcome: Classified as fatal if the individual does not survive.

Near Drowning

  • Definition: Respiratory impairment from submersion with survival, often needing medical intervention.

  • Outcome: Survivor may face respiratory distress, hypoxia, or complications.

Immersion

  • Definition: Being partially or completely submerged in a liquid; may not lead to breathing impairment.

  • Outcome: May occur accidentally without leading to drowning.

Submersion

  • Definition: Body fully or partially under water, typically causing breathing difficulties.

  • Outcome: Can lead to drowning if unable to surface.

STATISTICS AND EPIDEMIOLOGY

  • Drowning Deaths: Over 4,500 annually (2020-2022, CDC).

  • Children Aged 1-4: Leading cause of death.

  • Black Individuals: 28% increase in drowning rates (2019-2021).

  • American Indian/Alaska Native: Highest drowning rates.

  • Swimming Ability: ~40 million adults in the U.S. (15.4%) cannot swim; 54.7% never took lessons.

EPIDEMIOLOGY

Age Distribution of Drowning Deaths

  • First Peak: Children under 5 years; risks include lack of supervision and limited swimming ability.

  • Second Peak: Young adults (15-24 years); linked to risky behaviors in water-related activities.

DROWNING SEQUENCE

  1. Initial immersion

  2. Laryngospasm

  3. Gasping and respiratory struggle

  4. Water inhalation

  5. Loss of consciousness

  6. Cardiac arrest and death

PATHOLOGICAL REFLEXES

Reflex Laryngospasm

  • Description: Involuntary closure of vocal cords to prevent water entry.

  • Consequences: Can cause respiratory distress and hypoxia if prolonged.

Diver’s Reflex

  • Description: Physiological response when submerged in cold water.

  • Mechanism:

    • Bradycardia: Slowed heart rate.

    • Peripheral vasoconstriction: Redirection of blood flow to vital organs.

    • Blood Shift: Maintains blood volume for oxygen delivery.

    • Function: Conserves oxygen during submersion.

DRY DROWNING

  • Occurrence: Larynx closure prevents water entry.

  • Symptoms: Difficulty breathing, cough, shortness of breath.

  • Time Frame: Distress can occur minutes to hours post-event.

WET DROWNING

  • Occurrence: Relaxation of larynx allows water into lungs.

  • Symptoms: Difficulty breathing, foamy sputum, respiratory distress.

KEY PATHOLOGIC PULMONARY CHANGES

  • Laryngospasm: Initial protection but may fail.

  • Pulmonary Edema: Fluid accumulation in alveoli.

  • Surfactant Dysfunction: Impaired lung compliance.

  • Inflammatory Response: Further damage and gas exchange issues.

  • Hypoxia and Imbalances: Respiratory failure risk if untreated.

PULMONARY CONCERNS

  • Issues: Alveolar flooding, surfactant washout, decreased lung compliance, V/Q mismatch, refractory hypoxemia.

SALTWATER DROWNING

  • Osmotic Pressure: Higher salinity leads to fluid shift into lungs.

  • Symptoms: Pulmonary edema, electrolyte imbalances, arrhythmias.

FRESHWATER DROWNING

  • Osmotic Pressure: Lower salinity draws fluid into bloodstream.

  • Symptoms: Pulmonary edema, hemodilution, systemic complications.

PULMONARY EDEMA

  • Associated with: Pink, frothy sputum.

RECALL QUESTIONS

  • Q1: Definition of reflex laryngospasm? (B)

  • Q2: Physiological response NOT in diver’s reflex? (C)

PRE-HOSPITAL MANAGEMENT

  • Actions: Ensure scene safety, check responsiveness.

  • Airway Management: Rescue breathing, CPR, intubate if necessary.

  • Control Hypothermia: Remove wet clothes, warm the patient.

  • Transport: Rapid transport to hospital.

MANAGEMENT AT THE HOSPITAL

  • Monitoring: Vitals, ABG, chest X-ray, monitor for hypoxemia and acidosis.

  • Warming Techniques: Various methods for warming the patient and fluids.

AIRWAY CLEARANCE

  • Methods: Aspiration, bronchoscopy, prone positioning, antibiotics.

MECHANICAL VENTILATION AND ARDS

  • “Lung protective” strategies: Low tidal volume, permissive hypercapnia, increased PEEP.

NEUROLOGIC INJURIES

  • Management Goals: Prevent ischemia, cerebral edema, hypoxemia.

  • ICP Monitoring: Manage through ventilation; avoid prolonged hyperventilation.

GLASGOW COMA SCALE

  • Scoring: Assess eye opening, verbal response, and motor response.

  • Interpretation: Minor (13-15), Moderate (9-12), Severe (3-8) brain injury.

GENERAL PROGNOSIS - POOR OUTCOMES

  • Factors: Submersion duration, water temperature, initial cardiac rhythm, time to ROSC.

GENERAL PROGNOSIS - ADDITIONAL OUTCOMES

  • Factors: GCS score, need for CPR, ABG findings, age considerations.

FAVORABLE PROGNOSTIC FACTORS IN COLD-WATER NEAR DROWNING

  • Age: Younger individuals have better outcomes.

  • Submersion time: Shorter times relate to better survival odds.

  • Water quality: Cleaner water is favorable.

  • CPR quality: Good technique increases survival chance.

SELF-ASSESSMENT QUESTIONS

  • Q1: Importance of continuous CPR? (C)

  • Q2: Clinical manifestations of near-drowning? (a)

CRITICAL THINKING QUESTION

  • Reasoning behind cold water's protective effects and need for resuscitation efforts until body warmth is restored.