NEAR DROWNING

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NEAR DROWNING
Pediatric Critical Care Medicine Emory
University Childrens Healthcare of Atlanta
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Objectives

• Definition
• Incidence, epidemiology, causes
• Prognosis
• Interventions/managements
• Opportunities that impact outcome

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Definition

• Drowning die within 24 hours of a submersion
  incident
• Near Drowning survive at least 24 hrsafter a
  submersion incident
• 2002 World Congress all victims to be labeled as
  drowning

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Incidence/Epidemiology

• CDC 2012 for 2005-2009 for US
• 3,880 fatal drowning, 2X treated in ER for
  non-fatal drowning
• Leading cause of injury death among children 1-4
  yrs, highest rate
• 2nd leading cause of all accidental deaths lt14 yr
  (MVC 1st)
• Fatality malegtfemale (42.070.54/100,000
• African-American
• 1.3X higher than Caucasian
• 3.4X higher in 5-14 yo age group

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Incidence

• For every 1 death
• 4 others hospitalized a
• 14 seen in the ER
• incidence holidays, weekends and warm weather
• Children lt5 pools older kids and adults in open
  water
• Fatality 35 33 with neurological impairment
  11 severe neurologic sequelae

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Causes
Salt Water 1-2
Fresh water 98
swimming pools public 50
swimming pools private 3
lakes, rivers, streams, storm drains 20
bathtubs 15
buckets of water 4
fish tanks or pools 4
toilets 1
washing machines 1
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Causes

• Toddlers
• Lapse of supervision
• Afternoon/early evening-meal time
• 84 with responsible supervising adults
• Only 18 of cases actually witnessed

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Causes

• Recreational boating
• 90 of deaths due to drowning
• Vast majority are not wearing life jackets
• 1,200/yr
• Small, open boats
• 20 of deaths
• Too few or no floatation devices!
• Diving
• 700-800/yr
• 1st drive in unfamiliar water
• 40-50 alcohol related

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Causes

• Spas, hot tubs
• Entrapment in drains, covers
• Buckets drowning
• males/gtfemales
• African-Americansgtcaucasians
• Warm monthsgtcold

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Causes

• Epilepsy
• 1.5-4.6 had pre-existing seizure disorder
• gt5 yr, drown in bathtub, not be supervised
• Long QT syndrome
• Swimming may be a trigger for LQTS
• Near drowning may be first presentation
• Specific gene KVLQT1 mutation associated
  w/swimming trigger submersion

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aspiration of water (90)
Laryngospasm aborted
Aspiration Laryngospasm
Swallows water
Unexpected Submersion
anoxia, seizures and death without aspiration
(10)
Laryngospasm recurs
Stage I (0-2 minutes)
Stage II (1-2 minutes)
Stage III
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Pathophysiology

• Part I
• Voluntary breath-holding
• Aspiration of small amounts into larynx
• Involuntary laryngospasm
• Swallow large amounts
• Laryngospasm abates (due to hypoxia)
• Aspiration into lungs

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Pathophysiology

• Part II
• Decrease in sats
• Decrease in cardiac output
• Intense peripheral vasoconstriction
• Hypothermia
• Bradycardia
• Circulatory arrest, while VF rare
• Extravascular fluid shifts, diuresis

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Pathophysiology

• Diving reflex
• Bradycardia, apnea, vasoconstriction
• Relatively quite weak in humans
• better in kids
• Occurs when the face is submerged in very cold
  water (lt20C)
• Extent of neurologic protection in humans due to
  diving reflex is likely very minimal

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Pathophysiology

• Asphyxia, hypoxemia, hypercarbia, metabolic
  acidosis
• Fresh water vs salt water - little difference
  (except for drowning in water with very high
  mineral content, like the Dead Sea)
• Hypoxemia
• Occlusion of airways with water particulate
  debris
• Changes in surfactant activity
• Bronchospasm
• Right-to-left shunting increased
• Physiologic dead space increased

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Pathophysiology

• Cardiac arrhythmias
• Hypoxic encephalopathy
• Renal insufficiency
• Pulmonary injury
• Global brain anoxia potential diffuse cerebral
  edema

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Pathophysiology Cerebral edema

• Initial hypoxia
• Post resuscitation cerebral hypoperfusion
• Increased ICP
• Cytoxic cerebral edema
• BBB remains intact derangement in cellular
  metabolism resulting in inadequate functioning of
  the Na K pump
• Excessive accumulation of cytosolic calcium
  causing cerebral arterial spasm
• Lance-Adams syndrome with sign hypoxia
• Post hypoxic (action) myoclonus, often mistaken
  for sz
• Happens more often with coming out of sedation
• Must be differentiated from myoclonic status
  (poor prognosis)

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Pathophysiology Pulmonary Injury

• Aspiration as little as 1-3 cc/kg can cause
  significant effect on gas exchange
• Increased permeability
• Exudation of proteinaceous material in alveoli
• Pulmonary edema
• decreased compliance

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Pathophysiology fresh vs. salt

• Both forms wash out surfactant
• Damaged alveolar basement membrane ? pulmonary
  edema, ARDS
• Theoretical changes not supported clinically
• Salt water hypertonic pulmonary edema
• Fresh water plasma hypervolemia, hyponatremia
• Unless in Dead Sea
• Humans (most aspirate 3-4cc/kg)
• Aspirate gt 20cc/ kg before significant
  electrolyte changes
• Aspirate gt 11cc/kg before fluid changes

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Pathophysiology

• Findings at autopsy
• Wet, heavy lungs
• Varying amounts of hemorrhage and edema
• Disruption of alveolar walls
• 70 of victims had aspirated vomitus, sand, mud,
  and aquatic vegetation
• Cerebral edema and diffuse neuronal injury
• Acute tubular necrosis

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Pathophysiology Pulmonary edema

• Findings at autopsy
• Wet, heavy lungs
• Varying amounts of hemorrhage and edema
• Disruption of alveolar walls
• 70 of victims had aspirated vomitus, sand, mud,
  and aquatic vegetation
• Cerebral edema and diffuse neuronal injury
• Acute tubular necrosis

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Signs Symptoms

• 70 develops sxs within 7 hrs
• Alertness ? agitation ? coma
• Cyanosis, coughing pink frothy sputum (pulm
  edema)
• Tachypnea, tachycardia
• Low grade fever
• Rales, rhonchi less often wheezes
• Signs of associated trauma to the head neck
  should be sought

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Prognosis

• Better outcomes associated with early CPR
  (bystander)
• C-spine protection
• Transport
• Continue effective CPR
• Establish airway
• Remove wet clothes
• Hospital evaluation

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Labs Tests

• Min electrolyte changes
• Increase WBC
• Hct HgB normal initially
• Fresh water Hct falls due to hemolysis
• Inc. in free HgB w/o a change in Hct
• DIC occasionally
• ABG metabolic acidosis hypoxemia

• EKG
• Sinus tach, non spec ST-segment T-wave changes
• Resolved within hrs
• Ominous- vent arrhythmias, complete heart block
• CXR
• May be nl initially
• Patchy infiltrate
• Pulm edema

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Treatment

• ED eval
• Admit if CNS or respiratory symptoms
• Observe for 4-6 hours if
• Submersion gt1min
• Cyanosis on extraction
• CPR required

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Treatment ED discharge

• ED eval
• Admit if CNS or respiratory symptoms
• Observe for 4-6 hours if
• Submersion gt1min
• Cyanosis on extraction
• CPR required

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Predicting Ability for ED Discharge

• Several studies support selected ED discharge
• Child can safely be discharged home if at 6 hours
  after ED presentation
• GCS gt 13
• Normal physical exam/respiratory effort
• Room air pulse oximetry oxygen saturation gt 95

-Causey et al., Am J Emerg Med, 2000
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ICU treatment Respiratory

• PPV
• Treatment of bronchospasm
• Steroids no benefits
• Bronchoscopy
• Prophylactic abx no benefits
• Surfactant no beneficial

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ICU treatment Cardiovascular

• Re-warming
• CBF decrease 6-7 / ºC drop
• LOC 34ºC
• Pupil dilate at 30ºC
• V-fib 28ºC
• EEG isoelectris 20ºC

-
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ICU treatment CNS

• ICP monitoring - not indicated, typically
  irreversible hypoxic cellular injury
• Brain CT not indicated, unless TBI suspected
• Mild hyperventilation?
• Osmotherapy not indicated
• Corticosteroids (dexamethasone) - no proven
  benefit
• Seizures - treat aggressively
• Shivering or random, purposeless movements can
  increase ICP
• Hypothermia and barbiturate coma - highly
  controversial unlikely to benefit the patient
  (31 comatose kids, J Modell, NEJM 1993)

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ICU treatment Others

• Antibiotics no benefit or prophylaxis, may
  increase superinfection
• Fulminant strep pneumo sepsis has been described
  after severe submersion
• Steroids no demonstrated benefit

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Prognosis predictors

• Poor outcomes
• Age lt 3yrs
• Submersion time gt10 min
• Time to BLS gt10 min
• Serum pH lt7.0
• CPR gt25 min
• Initial core temp lt33ºC
• GCS lt5

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Prognosis predictors
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Prognosis predictors

• Prolonged resuscitation may increase the success
  of resuscitation w/o normal neurologic recovery
• ? After 25 min of full but unsuccessful
  resuscitation, thin PROGNOSIS

Submersion time survival Fatality
0-5 min 7/67 10
6-9 min 5/9 56
10-25 min 21/25 88
gt25 min 4/4 100
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Effects of near drowning

• Divorce
• Sibling psychosocial maladjustment
• 100,000 yrs of productive life lost
• 4.4 million/yr in direct health care costs
• 350-450 million/yr in direct costs
• 100,000/yr to care for the neurologically
  impaired survivor of a near drowing

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