1. Submersion Injuries
David A. Caro, MD FACEP
Department of Emergency Medicine

2. Submersion Injuries
s Drowning
s Near-Drowning
– Wet drowning
– Dry drowning
s Secondary Drowning
s Immersion Syndrome

3. Drowning
s 8000 deaths per year in US
s 4th most common cause of death in adults
s 3rd most common cause in children
s Males have 5 times greater death rate
s Blacks have 3 times higher death rate
s 40% of deaths are < 4 yrs old
s 50% of those who die in swimming pools
are < 10 yrs old

4. Risk Factors
s Age
s Location
s Gender
s Race
s Ability to Swim
s Drugs and Alcohol
s Underlying Disease

6. Submersion Injuries:
Pathophysiology
s Asphyxia: Anoxic and ischemic injury
s Fluid Overload
s Pulmonary Injury
s Hypothermia/Diving Reflex

7. Asphyxia/Hypoxia
s Breath holding +/- laryngospasm
s PAO2 falls rapidly in 1st minute
s PACO2 rises and pH falls less rapidly
s Hyperventilation - PACO2 rises less while
PAO2 falls at about the same rate

8. Pulmonary CNS
1. 2' Apnea - 1. Anoxic Damage
aspiration 2. Cerebral edema
2. Hypercapnia 3. Defective
autoregulation
4. Increased ICP
GI
1. Mucosal Hematologic
2. Liver inury ASPHYXIA 1. DIC
Renal
Cardiac 1. ATN
1. Ischemia 2. Acute cortical
2. Fibrillation necrosis

9. Fluid Overload
Swallowing large amounts of water:
– Gastric distention
– Vomiting
– Aspiration

10. Response to Submersion
s Stage I (0-2 min)
– Aspiration and laryngospasm
s Stage II (1-2 min)
– Swallows water
s Stage III (variable)
– Laryngospasm aborted (85-90%) and
aspiration of water
s Stage III (variable)
– Laryngospasm reoccurs with anoxia, sz,death

11. Fresh Water Drowning
s Hypotonic
– Hemodilution
s Decreased electrolytes, Hct, Hgb
– Hemolysis
s Hyperkalemia
s Increased CVP

12. Salt Water Drowning
s Hypertonic
– Draws water into respiratory tract
– Hemoconcentration
s Increase electrolytes, Hct, Hgb
s Decreases CVP

13. Fluid Aspiration
s Animal studies found that 22 ml/kg
needs to be aspirated before serum
electrolytes change
s Usual aspiration into lungs < 3-4 ml/kg,
however swallowed water can be
aspirated later
s In most series: serum electrolyte
changes are mild, non-life threatening

14. Pulmonary Injury
s Aspirated fluid decreased PaO2 due to reflex
contraction of terminal airways leading to V/Q
mismatch
s Fresh water destroys surfactant leading to alveolar
collapse and retards transudation of fluid causing
intrapulmonary shunt and hypoxemia
s Salt water leads to fluid filled but perfused alveoli
leading to intrapulmonary shunt and hypoxemia
s Aspiration of fluid leads to increased pulmonary
resistance and decreased compliance

15. Coagulopathy
Infection risk
Plt dysfunction Reduced drug
DIC metabolism
HYPOTHERMIA CNS:
Cardiac
1. Reduced metabolism
Arrythmias
2. Reduced ICP
3. Protection?
Vasodilation: 4. Clinical death pix
Decreased CVP/BP
Renal Failure Death

16. Hypothermia
s Exerts protective effects through
reducing cerebral metabolism
– decreases to 50% at temp of 28o C
– below 22o C, cerebral activity abolished
s Diving Reflex:
– Neurogenic reflex which shunts blood away
from nonessential organs
– Associated with bradycardia
– Triggered by submersion of the face, fear,
and cold water

17. Hypothermia
s May cause the following:
– Compromised neutrophil migration and release
– Decreased drug metabolism
– Abnormal platelet number, morphology, function
– Decrease cardiac contractility and arrhythmias
– Vasodilation, hypotension, renal failure, death

18. Clinical Presentation
s Variable presentation:
– Awake and alert
– Awake, lethargic
– Children may have had brief apnea
– Hx of choking, coughing or vomiting
– Comatose
– Cardiac arrest

19. Clinical Exam
s Pulmonary
– Resp distress, rhonchi, rales, wheezing
s Cardiovascular
– Arrythmias, ischemia
s GI
– Abd distention, vomiting, aspiration
s Neurological
– Signs of cerebral hypoxia
s Hypothermia
s Associated Injuries: C-spine

20. Prehospital Care
s Safety of rescue workers
s Pull victim out of water
s Mouth to mouth resuscitation
s Suspect head/neck injuries - backboard
s BCLS/ACLS as needed
s Administer oxygen
s Avoid heimlich maneuver/lung drainage
s Transport all patients

21. Emergency Department
Assessment
s ABC’s
s Vital signs - including rectal temp, pulse ox
s Oxygen

22. Asymptomatic Patient
s Hx - incident, submersion time, temp of water,
trauma involved, drug/alcohol, past health, current
complaints
s PE - also assess for other injuries
s Lab - ABG, CXR, CBC, Chem-7, U/A, think C-spine
s Tx - Oxygen at 8-10 liters, IV, Monitor, Observe for
4-12 hours

23. Symptomatic Patient
s HX/PE - same as for asymptomatic pt
s Lab - consider PT/PTT, LFT’s, CPK’s
s Tx
– open airway, remove emesis particles, NGT
– oxygenate at 10 l/min
– consider CPAP or intubate with PEEP
– Warm patient
– Hospitalize in monitored environment

24. CPR
s Airway and intubation
s ACLS protocol with attention to acidosis
s C-spine protection
s Mechanical ventilation with PEEP
s No steroids or prophylactic antibiotics
s Maintain urine output at 50 cc/hr

25. Respiratory Assessment
s Clear the airway, achieve ventilation
s ABG
s CXR
s Assess gag and cough reflexes, ability
to protect airway

26. Intubation
s If pCO2 > 50
s If pt requires > 40% FiO2 to maintain
adequate paO2
s Gross pulmonary edema
s Poor or absent cough and gag reflexes

27. Ventilation
s CPAP - spontaneously breathing with
hypoxia
s PEEP - decreases intrapulmonary
shunting, reduces V/Q mismatch, and
increases the functional residual
capacity resulting in increased PaO2
s PEEP may also prevent secondary
drowning from RDS
s PEEP disadvantage - may worsen
cerebral edema

28. Ventilation
s Persistent hypoxia may be result of
aspirated foreign material - aggressive
suctioning or bronchoscopy may help
s ECMO - consider in patients unresponsive
to 100% oxygen and PEEP

29. Pulmonary
s Bronchospasm can be treated with
beta-agonists
s Steroid administration has not shown
survival benefit
s Prophylactic antibiotics have not
demonstrated improved survival

30. Cardiovascular
s Monitor HR, rhythm, BP, cap refill, UO
s Consider CVP/PAWP monitoring
s Adequate fluid resuscitate before using pressors
s Monitor volume status
s Treat metabolic acidosis with bicarb

31. Neurologic Assessment
s Primary importance for prognosis
s Assess level of consciousness - AVPU
s Assess GCS
s Level of consciousness in ED:
– A - Awake
– B - Blunted
– C - Comatose
s C1 - decorticate
s C2 - decerebrate
s C3 - flaccid

32. Cerebral Resuscitation
s Goal is to keep ICP below 20 mm Hg and
CPP above 50 mm Hg
s Primarily depends on rapid stabilization,
correction of hypoxia and acidosis
s Treat agitation, seizures
s Treat increased ICP:
– elevate head, hyperventilate
– osmotic and loop diuretics
– barbiturates

33. Cerebral Resuscitation
s Unproven therapies:
– therapeutic dehydration
– induced hypothermia
– barbiturate coma
– paralysis
– Ca channel blockers
– oxygen radical scavengers

34. GI
s NG drainage
s Control gastric pH

35. Hypothermia Management
s Below 28’ C - arrhythmias occur
s Below 25’ C - hypotension
s Management:
– Remove wet clothes
– Internal rewarming techniques
s NG irrigation, enemas, Foley, lavage
s If pt sustained prolonged hypoxia/asphyxia
consider maintaining core temp near 30’ C

36. Prognostic Variables
s At the Scene:
– Length of submersion
s > 5 minutes associated with poor outcome
– Water temperature
– CPR initiated
– First gasp within 5 minutes of CPR

37. Prognostic Variables
s In the ED:
– CPR still required
– pH < 7.0 - 7.1
– Submersion hypothermia
– Mechanical ventilation
– Level of consciousness
– Pupils

38. Pediatric Survival
s Unfavorable outcome if
– comatose state
– lack of pupillary reflex
– male sex
– initial blood glucose concentration
s In 194 children, rule was 100% specific with
65% sensitivity
Graf, Ann Emerg Med, 1995

39. Secondary Drowning
(Post immersion syndrome)
s Onset delayed from 1 to 72 hours
s Occurs in 2-15% of near drowning cases
s Respiratory deterioration and possible death
s Mechanism:
– loss of surfactant from chemical, anoxic or
osmotic damage to the pneumatocytes

40. Immersion Syndrome
s Sudden death after immersion in very
cold water
s Cause thought to be vagally-mediated
bradyasystolic cardiac arrest or
ventricular fibrillation

41. Drowning Prevention
s Environmental
s Parent-related
s Factors related to children

42. Drowning Prevention
s Public education
s Legislation
s Proper supervision
s Mandatory CPR for pool owners
s Mandatory swimming lessons for children
s Proper use of life preservers