Immersion and near drowning Drowning is... Death secondary

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Immersion and near drowning
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Drowning is...

• Death secondary to asphyxia while immersed in a
  liquid, usually water, or within 24 hours of
  submersion

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Accidental drowning in Australia the scale and
context of the problem - 1992-1998

• Fell into water 748 34
• Swimming 600 27
• Watercraft 343 16
• Bath 131 6
• Swept off rocks 91 4
• Scuba diving 83 4
• Attempting rescue 41 2
• Surfing 20 1
• Total 2199 100

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Factors increasing the risk of drowning

• Toddler and adolescent age groups
• Pools / dams / drains etc in children
• Water with currents / rips / waves
• Colder water
• Alcohol and drugs (esp. in men)
• Associated head and neck injury
• Fatigue

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Cold water (lt10C) immersion is different from
that in warmer water
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• In warm water death from drowning, slow onset
  hypothermia
• In cold water stress response may cause early
  death, so too can drowning, hypothermia may be
  protective in total immersion, hypothermia is a
  late (gt30 mins ) cause of death

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In drowning...

• air hunger and usually panic
• Reflex inspiratory efforts lead to aspiration of
  water and laryngospasm
• asphyxia and hypoxaemia / acidosis

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Asphyxia

• Laryngospasm maintained
• Respiratory arrest
• Cardiac arrest
• Dry drowning

• Relaxation of the airway
• Water enters lungs
• Surfactant washout
• V / Q mismatch
• Wet drowning

mechanism in fresh and salt water slightly
different
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In cold water...Cold stress leads to

• Respiratory and cardio-vascular responses
• Gasp reflex
• Mammalian dive reflex (total immersion or
  face-only) esp. in young children, very cold
  water, excessive stress

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Gasp reflex leads to hyperventilation

• Panic
• Aspiration
• Drowning

• ?CO2
• Respiratory alkalosis
• Cerebral vaso-constriction
• ?mental functioning
• Possible convulsions

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• Gasp reflex settles after about 3 minutes
• (if youre still alive)

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Cardiac response to cold stress in the first few
minutesTotal body immersion / face only
immersion?

• NO
• Sympathetic activation
• 8 temp of water
• ?heart rate
• ?BP
• arrhythmias

• YES
• Diving reflex
• ?heart rate
• ?cardiac output
• ?mean arterial p.
• ?total peripheral resistance

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Essential First Aid Management

• Conscious Unconscious
• Evaluate for CPR (prolonged)
• Aspiration 100 oxygen
• NO YES
• Observe 100 oxygen transfer to hospital

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The problem with looking well...

• Aspiration of water can cause late complications
• Neurogenic pulmonary oedema, Pneumonia, SIRS,
  DIC, Haemolysis, Hepatic renal failure, bowel
  necrosis
• Plus complications of hypothermia

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Assessing aspiration

• Historical factors
• Prolonged head immersion
• L.O.C.
• Period of apnoea
• CPR required
• Impression of choking

• Symptoms / signs
• Cough, breathlessness,
• Retrosternal discomfort
• Cyanosis, tachycardia
• Tachypnoea, wheeze or
• Crackles in chest
• Pink frothy sputum
• Reduced consciousness

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Immediate hospital management

• Assess and manage ABC
• 100 oxygen
• Pulse oximetry (watch for false readings caused
  by peripheral shutdown and acidosis)
• ABGs, FBC, UE
• CXR
• Observation
• Management of associated hypothermia