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Pediatric Near Drowning. Fellows conference July 19, 2007. Question 1. True or False? Near drowning is the accounts for the highest unintentional death in children?. Question 2. Aspiration of ____ cc/kg is required before altered blood volume
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Pediatric Near Drowning Fellows conference July 19, 2007
Question 1 • True or False? • Near drowning is the accounts for the highest unintentional death in children?
Question 2 • Aspiration of ____ cc/kg is required before altered blood volume • Aspiration of ____ cc/kg is required before electrolyte abnormalities • Most near drowning victims aspirate ____ cc/kg
Question 3 • True or false? • Increased intracranial hypertension is the most significant contribution to CNS injury in the first 24 hours?
Question 4 • Children with seizure disorders are more likely to drown where?
Question 5 • True or false ? • If there is a family history of near drowning one can do genetic testing which may further identify family members at risk? • There is a clinical test which may also be helpful?
Near Drowning • Objectives • Define near drowning • Discuss • incidence • epidemiology • causes • Review prognostic indicators • Discuss therapeutic interventions • Discuss opportunities that impact outcome
Near DrowningDefinitions • Drowning: To die within 24 hours of a submersion incident • Near Drowning: To survive at least 24 hours after a submersion incident (submersion)
Near DrowningIncidence • 140,000 annual submersion deaths worldwide • 6-8,000 deaths in USA • > 7000 additional pts. require medical attention • incidence: holidays, warm weather • Leading cause of injury in toddlers • 3rd leading cause of all death < 15 yr. • 2nd leading cause of all accidental deaths
Near Drowning • “Tragically 90% of all fatal submersion incidents occur within ten yards of safety.” Robinson, Ped Emer Care; 1987
Relative Contribution of Various Submersion Media to Drowning Accidents
Near DrowningGroups at Risk • Toddlers (40% of deaths < 5 y.o.) • School age boys • Teenagers • Males > females (5:1) • African-American children • Children with: • seizures • cardiac dysrhythmias
Toddler Drownings • Tend to occur because of lapse in supervision • Majority in afternoon/early evening-meal time • Responsible supervising adult in 84% of cases • Only 18% of cases actually witnessed
Causes of Near DrowningRecreational Boating • 90% of deaths due to drowning • 1,200/year • Small, open boats • 20% of deaths • too few or no floatation devices !
Other CausesDiving Injuries • 700-800 per year • Peak incidence 18-31 years • No formal training • 1st dive in unfamiliar water • 40-50% alcohol related
Other CausesSpas, Hot Tubs • Entrapment • drains • hair, body parts, clothing • winter pool/spa covers
Bucket Drowning 1984-1989Risks • Males > females • African-Americans > Caucasians • Warm months > cold • Peak = October
Near-Drowning Epilepsy • 2.5-4.6% of drowning victims had pre-existing seizure disorder • Drowned children with epilepsy more likely to: be older than 5, drown in bathtub, not be supervised • Relative risk of drowning for children with epilepsy: • 96 in bathtub (95% CI 33-275) • 23 in pool (95% CI 7.1-77.1) -Diekema et al., Pediatrics 1993
Near-Drowning Long QT Syndrome (LQTS) • Swimming may be a trigger for LQTS event • Near-drowning event may be first presentation of LQTS (15% of 1st LQTS syncopal events) • Gene-specific KVLQT1 mutation associated with swimming trigger and submersion event • Can test with cold water face immersion • Importance: early diagnosis of survivor, or of family members; consider with unexplained submersion -Ackerman et al., NEJM 1999
aspiration of water (90%) laryngospasm aborted aspiration and 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
Pathophysiology of Anoxia Pulmonary Heme CNS Hypercapnea DIC Anoxic damage Cerebral edema Defective autoregulation Increased ICP GI Asphyxia Hypercapnea Mucosal sloughing Cardiac Renal Myocardial ischemia Fibrillation ATN
Near DrowningMulti-Organ Effects • Hypoxic/ischemic cerebral injury • Fluid overload • Pulmonary injury • Hypothermia
Near DrowningMulti-Organ Effects • Cerebral hypoxia is the final common pathway in all drowning victims
Near DrowningCNS Injury • Initial Hypoxia • Post resuscitation cerebral hypoperfusion • Increased ICP (doubtful) • Cytotoxic cerebral edema • Excessive accumulation of cytosolic calcium causing cerebral arteriolar spasm • Increased free radicals
Near DrowningCNS Injury • With significant hypoxia can have Lance-Adams syndrome • Post hypoxic (action) myoclonus • Often mistaken for seizures • Happens more often when coming out of sedation • Must be differentiated from myoclonic status which has poor prognosis
Near DrowningPulmonary 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
Near DrowningPulmonary Injury:Fresh Water vs. Salt Water • 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 > 20cc/ kg before significant electrolyte changes • Aspirate > 11cc/kg before fluid changes
The Bottom LineFresh Water and Salt Water • Both forms wash out surfactant • Damaged alveolar basement membrane • Pulmonary edema • ARDS
Effect of Immediate Resuscitation on Outcome • Review of 166 near-drowning children in California • Children with good outcome 4.75 times more likely to have had immediate bystander CPR than poor outcome patients -Kyriacou et al., Pediatrics, 1994
TreatmentPre-Hospital • Immediate, effective CPR • Oxygenation, ventilation ASAP • Chest compressions • C-spine stabilization • Avoid drainage procedures
C-Spine Injuries Among Submersion Victims • “Immobilize all near-drowning patients” • 2244 submersion victims - Washington • 11 C-spine injuries (0.5%) • All 11 in open bodies of water; all had history of diving (RR 229), MVC, fall; witnessed, > 15 • No C-spine injury in 880 low-impact events • “Routine immobilization does not appear to be warranted” -Watson et al., J Trauma 2001
TreatmentTransport • Continue CPR • Establish airway • Remove wet clothes • Hospital evaluation
TreatmentEmergency Department • Continue established therapies • History, physical, labs • Admit if: CNS or respiratory symptoms • Observe in ED for minimum 4-6 hours if: • Submersion > 1 min. • Cyanosis on extraction • CPR required
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 > 13 • Normal physical exam/respiratory effort • Room air pulse oximetry oxygen saturation > 95% -Causey et al., Am J Emerg Med, 2000
ICU Management StrategiesNon-invasive Ventilation • Nasal /face mask • Increase in small increments to maintain: • FIO2 < 0.40 • QS/QT < 20% • PaO2/FIO2 > 300 • Wean slowly
ICU Management StrategiesIntubation/VentilationIndications • SpO2 < 90% on FIO2 > 0.6 • PaCO2 > 50 with pH < 7.3 • Increased work of breathing • Abnormal CNS exam
ICU Management StrategiesRespiratory • Oxygenate - avoid hypoxemia • Ventilate - avoid significant hyperventilation • PEEP may be beneficial but is not prophylactic • Exogenous surfactant
Management StrategiesCardiovascular • Re-warming ( to a degree ? benefit hypothermia) • LOC 34 C • Pupils dialate 30 C • V Fib 28 C • EEG iso-electric 20C • CBF decrease 6-7% per degree C drop
Management StrategiesCentral Nervous System • Protect against 20 injury • Perfuse it or lose it !! • ICP monitoring not beneficial or recommended • Some still monitor if: • Successful CPR followed by coma • Sudden, unexplained deterioration
Management Strategies Problem: “Studies evaluating results of cerebral resuscitation measures have failed to demonstrate that treatment directed at controlling increased intracranial pressure and maintaining normal cerebral perfusion pressure improves outcome” Orlowski, PCNA 34:85, 1987
Historical Therapy: HYPER-Directed Therapy • Hyper-hydration: diuretics • Hyperventilation: hypocarbia via controlled ventilation • Hyperpyrexia: aggressive hypothermia to 30 degrees C • Hyperexcitability: pentobarbital coma • Hyperrigidity: neuromuscular blockade -Conn et al., Can J Anesth 1979
CONN (Toronto) - HYPER Therapy -Conn et al., Can J Anesth 1979
MODELL (FL) - NO HYPER Therapy -Modell et al, Crit Care Med, 1984
Management StrategiesCentral Nervous System • ICP monitoring may not change outcome, just predict it • Low ICP Better outcome • High ICP Poor outcome -Sarnaik et al., Crit Care Med, 1985
ICU Management StrategiesOther Issues • Antibiotics - no benefit of prophylaxis, may increase super-infection • Fulminant Strep pneumoniae sepsis has been described after severe submersion • Steroids - no demonstrated benefit
Factors Considered Predictive of Poor Submersion Outcome • Submersion time • Serum pH • Need for CPR in the E.D. • Time to first gasp • Neuro evaluation Survive or not?
Peterson 1977Anoxic encephalopathy if: CPR in ER Submersion > 5 minutes Seizures, flaccidity, fixed/dilated pupils, coma in E.D. Near DrowningPrognostic Indicators
Pearn 1979Time to first spontaneous gasp: < 5 minutes - most survive > 60 minutes -CNS injury inevitable Allman 1986 GCS = 3 in ICU: Death or vegetative state Near DrowningPrognostic Indicators
Near DrowningOrlowski Prognostic Criteria • Age < 3 years • Estimated submersion > 5 min. • No CPR > 10 min. • Coma in ED • pH < 7.10