1. Submersion Injuries Richard Dionne MD CCFP-EM Assistant Professor Emergency Medicine - Ottawa Hospital-University of Ottawa Associate Medical Director - Regional Paramedic Program for Eastern Ontario Fellowship Director EMS & Disaster Medicine April 1 st, 2010

2. Near Drowning Objectives Understand causal conditions Differentiate between fresh & salt water drownings Identify potential injuries Select appropriate diagnostic & management Consider treatment of hypothermia & trauma

3. Diving Emergency?

4. Definitions Drowning: –terminal outcome from submersion event Near-drowning: AHA no longer uses Submersion Injuries: – survival, at least temporarily, after suffocation in a liquid medium 3 rd most common cause of accidental death overall, leading cause in < 5 yo ETOH / Drugs often associated

5. Risk Factors Inability to swim (overestimation of capabilities) Risk taking behaviour Inadequate supervision (bathtub, pools) Co morbidity: trauma, seizure, CVA, cardiac

6. 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

7. Profound hypoxia Respiratory acidosis, ARDS Cardiovascular collapse Neuronal injury …. Death End Organ Effect

8. Immersion Syndrome Syncope secondary to cardiac dysrhythmias on sudden contact with water at least 5 o C < body T QT prolongation & massive release of catecholamines plus vagal stimulation =>VF & asystole Resultant LOC leads to drowning

9. 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!

10. Submersion Injuries Fresh waterSalt water No difference  Surfactant is destroyed  Alveolar instability  Atelectasis &  Compliance & Bronchospasm  V/Q mismatch  Hypoxia

11. 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

12. 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 ?

13. Management of Care Prehospital Emergency Inpatient

14. Prehospital On scene: –Immediate Rescue Breathing (even before out of water)… –Heimlich not proven … –Bystander CPR (pulse check 30 sec.) –Consider trauma: C-spine precautions –Remove wet clothing, passive external rewarming (Hypothermia!)

15. Emergency Department ABC’s Early airway management Monitor: –cardiac, CORE T °(rectal) Rewarming Passive External Active External Active Internal

16. Inpatient Management Goal: prevent further secondary neurologic injury and minimise end-organ damage.

17. 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

18. 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

19. 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

21. 4 hours later….

22. Factors Affecting Survival Age Water temperature Duration & degree of hypothermia Diving reflex Resuscitation efforts Prior medical conditions

23. Good vs Bad ???

24. 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

25. 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

26. Who can go home? Asymptomatic on presentation Maintains normal room air sat No CXR or ABG abnormalities …… D/C after 8 hour observation

27. Prevention YChildren supervision YCPR courses to families with pools YBoating sobber & lifevests YDiving injuries YCaution: CAD / Seizure / Diabetics

28. 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 H 2 O Majority of treatment is supportive, rewarming & not underestimate … Prevention !!! Monitor x 6-8 hr for asymptomatic pt with normal investigations

29. Questions ?