Submersion Injuries Richard Dionne MD CCFP-EM Avik Nath MD CCFP EM March 21, 2013.
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Transcript of Submersion Injuries Richard Dionne MD CCFP-EM Avik Nath MD CCFP EM March 21, 2013.
Submersion Injuries
Richard Dionne MD CCFP-EMAvik Nath MD CCFP EM
March 21, 2013
Near Drowning Objectives
• Understand causal conditions
• Differentiate between fresh & salt water drownings
• Identify potential injuries
• Select appropriate diagnostic & management
• Consider treatment of hypothermia & trauma
Diving Emergency?
Definitions
• Drowning: – terminal outcome from submersion event – A process resulting in primary respiratory impairment from
submersion or immersion in a liquid medium
• Near-drowning: AHA no longer uses
• Submersion Injuries (non-fatal drowning): – survival, at least temporarily, after suffocation in a liquid
medium
• 3rd most common cause of accidental death overall, leading cause in < 5 yo
• ETOH / Drugs often associated
Risk Factors
• Inability to swim (overestimation of capabilities)
• Risk taking behaviour
• Inadequate supervision (bathtub, pools)
• Co morbidity: trauma, seizure, CVA, cardiac
Pathophysiology
Aspiration of 1-3 mL/kg destroys integrity of pulmonary surfactant
( lung compliance)
Alveolar collapse, atelectasis, Non-cardiogenic pulmonary edema
(ARDS), Intrapulmonary shunting, V/Q mismatch
Profound hypoxiaRespiratory acidosis, ARDS
Cardiovascular collapseNeuronal injury
…. Death
End Organ Effect
Immersion Syndrome
• Syncope secondary to cardiac dysrhythmias on sudden contact with water at least 5oC < body T
• QT prolongation & massive release of catecholamines plus vagal stimulation
• =>VF & asystole
• Resultant LOC leads to drowning
Salt vs Fresh Water: Does it Make a Difference?
• Historically felt to affect electrolytes, fluid shifting, hemolysis
• Intravascular abnormalities do not occur until aspirated water > 11 mL/kg
• Most aspirate <4 mL/kg
• Review of 91 submersion victims, no pt required emergent intervention for electrolyte abN
No significant clinical difference between the two!
Submersion Injuries
Fresh water Salt water
No difference
Surfactant is destroyed
Alveolar instability
Atelectasis & Compliance & Bronchospasm
V/Q mismatch
Hypoxia
Case
• 18 yo male• Boating with friends, “3 beers”• Fell off boat, submersion x 3 min• Brought to boat by friends, rescue
breathing started immediately
• What are the potential problems this pt may have?
• What is your immediate management?
• What investigations will you order?
• What is his prognosis?
• Which victims of submersion can I discharge?
Management of Care
• Prehospital
• Emergency
• Inpatient
Prehospital
• On scene:– Immediate Rescue Breathing (even before out of
water)… – Heimlich not proven …
– Bystander CPR (pulse check 30 sec.)• DO ABC’s as opposed to CAB!
– Consider trauma: C-spine precautions• 2000 pt study• 0.5 % (11 pts only) had C-spine injury• Usually obvious that injury occured
– Remove wet clothing, passive external rewarming (Hypothermia!)
Emergency Department
• ABC’s• Early airway
management
• Monitor: – cardiac, CORE T °(rectal)
• Rewarming
• Passive External• Active External • Active Internal
Inpatient Management
• Goal: • prevent further secondary neurologic injury and
minimise end-organ damage.
Submersion Injuries
• Gen: hypothermia, trauma
• GI: vomiting (swallow >> aspirate)
• Respiratory:– +’ve pressure
ventilation leads to gastric distention, risk of aspiration
– Aspiration of particulate contaminants
– Hypoxia from direct surfactant effects
– ARDS
Submersion Injuries
• CVS: dysrhythmias
• CNS: initial hypoxic injury or secondary reperfusion injury with resuscitation
• Renal: ARF due to lactic acidosis, prolonged hypoperfusion, rhabdo
• Heme: coagulopathies
What Investigations Do You Need?
• ECG: for dysrhythmias, prolonged QT
• ABG: any resp signs/symptoms
• Labs: electrolytes, renal function, CBC, glucose although usually N
• Screening for ETOH, drugs
• CXR: may underestimate severity initially
4 hours later….
Factors Affecting Survival
• Submersion > 10 min• CPR > 10 min• Resuscitation > 25 min• Water temo > 10 degrees• Age < 3• GCS < 5• ABG < 7.1 in Ed
Good vs Bad ???
Hypothermia: Good or Bad??
• Lowers cerebral metabolic rate, neuroprotective
• Diving reflex: shunting of blood centrally in response to cold water stimulus
• Causes bradycardia & apnea, decreased metabolic consumption
• Prolonged duration of submersion better tolerated
• Risks of malignant dysrhytmias
Poor Prognostic Factors
• > 10 minutes submersion• CPR initiated >10 min after rescue• Severe acidosis (pH < 7.1)• Unreactive pupils• GCS = 3 (comatose)• Hypothermia in ED ?• Need for ongoing CPR• Lack of spontaneous movement at
24hrs
Who can go home?
• Asymptomatic on presentation• Maintains normal room air sat• No CXR or ABG abnormalities …… D/C after 8 hour observation
Prevention
Children supervision
CPR courses to families with pools
Boating sobber & lifevests
Diving injuries
Caution: CAD / Seizure / Diabetics
Submersion Injuries: Overview
• Immediate resuscitative efforts is key!
• Consider associated trauma, ETOH/drugs
• Development of pulmonary injury may take time, initial CXR may be normal
• No clinical difference b/w salt & fresh H2O
• Majority of treatment is supportive, rewarming & not underestimate … Prevention !!!
• Monitor x 6-8 hr for asymptomatic pt with normal investigations
Questions ?