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DrowningDrowning
DR MAHMOUD MOHAMED MAHMOUD
DrowningDrowning ObjectivesObjectives
Define drowningDefine drowning DiscussDiscuss
• incidenceincidence• epidemiologyepidemiology• causescauses
Review prognostic indicatorsReview prognostic indicators Discuss therapeutic interventionsDiscuss therapeutic interventions Discuss opportunities that impact outcomeDiscuss opportunities that impact outcome
2002 World Congress on Drowning2002 World Congress on Drowning
Drowning = process resulting in primary Drowning = process resulting in primary respiratory impairment from respiratory impairment from submersion/immersion in a liquid mediumsubmersion/immersion in a liquid medium
RegardlessRegardless of survival of survival Drowning without aspiration does Drowning without aspiration does notnot
occuroccur Terms which are “out”Terms which are “out”
Dry, wet, active, silent, secondary, near-Dry, wet, active, silent, secondary, near-drowningdrowning
Near DrowningNear Drowning
DefinitionsDefinitions Definitions were revised at 2002 World Definitions were revised at 2002 World
congress on Drowning in Amsterdam, congress on Drowning in Amsterdam, Netherlands. They are now Netherlands. They are now internationally accepted and more internationally accepted and more uniformuniform
DrowningDrowning
StatisticsStatistics
1995 data:1995 data: >1000 kids <14 years old drown>1000 kids <14 years old drown 60% <4 years old60% <4 years old
2000 CDC data:2000 CDC data: 3,281 unintentional drownings in USA (adults & kids)3,281 unintentional drownings in USA (adults & kids) averaging 9 people/day - not including boating-related averaging 9 people/day - not including boating-related
incidents incidents 2003 CDC data:2003 CDC data:
For every child who drowns, 3 need ED care for non-For every child who drowns, 3 need ED care for non-fatal submersion injuriesfatal submersion injuries
>40% of these children require hospitalization>40% of these children require hospitalization
EPIDEMIOLOGYEPIDEMIOLOGY
Freshwater drowning is more Freshwater drowning is more common than saltwater drowning, common than saltwater drowning, even in coastal areaseven in coastal areas
Places:lakes/rivers/canals/poolsPlaces:lakes/rivers/canals/pools Toddlers:Toddlers:
Any container of water can be Any container of water can be responsible:responsible:• Buckets/fish tanks/washing Buckets/fish tanks/washing
machine/toilets/bathtubmachine/toilets/bathtub
Morbidity & MortalityMorbidity & Mortality
15% of children admitted for drowning die 15% of children admitted for drowning die in the hospitalin the hospital
As many as 20% of drowning survivors As many as 20% of drowning survivors suffer severe, permanent neurological suffer severe, permanent neurological disabilitydisability
Drowning modalitiesDrowning modalities
Infants (age <1) - bathtubs, buckets & Infants (age <1) - bathtubs, buckets & toiletstoilets
Children ages 1-4 years - swimming Children ages 1-4 years - swimming pools, hot tubs & spaspools, hot tubs & spas
Children ages 5-14 years - swimming Children ages 5-14 years - swimming pools & open water sitespools & open water sites
Bucket drowningsBucket drownings
~500 children in the US ~500 children in the US since 1984since 1984
7-15 months of age7-15 months of age 24 to 31 inches tall24 to 31 inches tall Bucket may contain water or Bucket may contain water or
nasty cleaning fluidnasty cleaning fluid
Tub drowningsTub drownings Approximately 10% of childhood drowningsApproximately 10% of childhood drownings Typically lacking adult supervisionTypically lacking adult supervision Do tub seats help?Do tub seats help?
Baby swim classesBaby swim classes
Done to “teach” babies to floatDone to “teach” babies to float No reported drownings in classNo reported drownings in class Several reports of hyponatremic seizures Several reports of hyponatremic seizures
following class following class (How was school today?)(How was school today?)
False sense of security?False sense of security?
Near DrowningNear DrowningGroups at RiskGroups at Risk
Toddlers (40% of deaths < 5 y.o.)Toddlers (40% of deaths < 5 y.o.) School age boysSchool age boys TeenagersTeenagers Males > females (5:1)Males > females (5:1) Children with:Children with:
seizuresseizures cardiac dysrhythmiascardiac dysrhythmias
Near DrowningNear DrowningRisk Factors: AgeRisk Factors: Age
0
100
200
300
400
500
600
0-4 yr 5-9 yr 10-14 yr 15-19
Male
Female
Toddler DrowningsToddler Drownings
Tend to occur because of lapse in Tend to occur because of lapse in supervisionsupervision
Majority in afternoon/early evening-meal Majority in afternoon/early evening-meal timetime
Responsible supervising adult in 84% of Responsible supervising adult in 84% of casescases
Only 18% of cases actually witnessedOnly 18% of cases actually witnessed
Causes of Near DrowningCauses of Near DrowningRecreational BoatingRecreational Boating
90% of deaths due 90% of deaths due to drowningto drowning
1,200/year1,200/year Small, open boatsSmall, open boats 20% of deaths20% of deaths
too few or no too few or no floatation devices !floatation devices !
Other CausesOther CausesDiving InjuriesDiving Injuries
700-800 per year700-800 per year Peak incidence Peak incidence
18-31 years18-31 years No formal trainingNo formal training 1st dive in 1st dive in
unfamiliar waterunfamiliar water 40-50% alcohol 40-50% alcohol
relatedrelated
Other CausesOther CausesSpas, Hot TubsSpas, Hot Tubs
EntrapmentEntrapment drainsdrains
• hair, body parts, clothinghair, body parts, clothing winter pool/spa coverswinter pool/spa covers
Near-Drowning Near-Drowning EpilepsyEpilepsy
2.5-4.6% of drowning victims had pre-2.5-4.6% of drowning victims had pre-existing seizure disorderexisting seizure disorder
Drowned children with epilepsy more likely Drowned children with epilepsy more likely to: be older than 5, drown in bathtub, not to: be older than 5, drown in bathtub, not be supervisedbe supervised
Relative risk of drowning for children with Relative risk of drowning for children with epilepsy:epilepsy: 96 in bathtub (95% CI 33-275)96 in bathtub (95% CI 33-275) 23 in pool (95% CI 7.1-77.1) 23 in pool (95% CI 7.1-77.1)
Near-Drowning Near-Drowning Long QT Syndrome (LQTS)Long QT Syndrome (LQTS)
Swimming may be a trigger for Swimming may be a trigger for LQTS eventLQTS event
Near-drowning event may be Near-drowning event may be first presentation of LQTS (15% first presentation of LQTS (15% of 1st LQTS syncopal events)of 1st LQTS syncopal events)
Gene-specific KVLQT1 mutation Gene-specific KVLQT1 mutation associated with swimming associated with swimming trigger and submersion eventtrigger and submersion event
Can test with cold water face Can test with cold water face immersion immersion
Importance: early diagnosis of Importance: early diagnosis of survivor, or of family members; survivor, or of family members; consider with unexplained consider with unexplained submersionsubmersion
PathophysiologyPathophysiology
The event, part 1The event, part 1 Voluntary breath-holdingVoluntary breath-holding Aspiration of small amounts into Aspiration of small amounts into
larynxlarynx Involuntary laryngospasmInvoluntary laryngospasm Swallow large amountsSwallow large amounts Laryngospasm abates (due to Laryngospasm abates (due to
hypoxia)hypoxia) Aspiration into lungsAspiration into lungs
The event, part 2The event, part 2
Decrease in satsDecrease in sats Decrease in cardiac outputDecrease in cardiac output Intense peripheral vasoconstrictionIntense peripheral vasoconstriction HypothermiaHypothermia BradycardiaBradycardia Circulatory arrest, while VF rareCirculatory arrest, while VF rare Extravascular fluid shifts, diuresisExtravascular fluid shifts, diuresis
Pathophysiology Pathophysiology withwith aspirationaspiration
HypoxemiaHypoxemia Occurs whether or not patient aspiratesOccurs whether or not patient aspirates 85-90% aspirate85-90% aspirate 10-15% DO NOT aspirate10-15% DO NOT aspirate
Pathophysiology Pathophysiology withwith aspirationaspiration
Pulmonary EdemaPulmonary Edema Damage to Alveolar membraneDamage to Alveolar membrane Damage to pulmonary microcirculationDamage to pulmonary microcirculation
Pathophysiology Pathophysiology withoutwithout aspirationaspiration
Severe, persistent laryngospasmSevere, persistent laryngospasm Anoxic seizuresAnoxic seizures DeathDeath
PathophysiologyPathophysiology
3 Major metabolic abnormalities3 Major metabolic abnormalities AnoxiaAnoxia AcidosisAcidosis HypercapniaHypercapnia
Pathogenesis 1Pathogenesis 1 Asphyxia, hypoxemia, hypercarbia, & metabolic acidosisAsphyxia, hypoxemia, hypercarbia, & metabolic acidosis Fresh water vs salt water - little difference (except for Fresh water vs salt water - little difference (except for
drowning in water with very high mineral content, like the drowning in water with very high mineral content, like the Dead Sea)Dead Sea)
HypoxemiaHypoxemia Occlusion of airways with water & particulate debrisOcclusion of airways with water & particulate debris Changes in surfactant activityChanges in surfactant activity BronchospasmBronchospasm Right-to-left shunting increasedRight-to-left shunting increased Physiologic dead space increasedPhysiologic dead space increased
Pathogenesis 2Pathogenesis 2
Cardiac arrhythmiasCardiac arrhythmias Hypoxic encephalopathyHypoxic encephalopathy Renal insufficiencyRenal insufficiency Global brain anoxia & potential diffuse Global brain anoxia & potential diffuse
cerebral edemacerebral edema
SaltSaltvsvs
FreshFresh
There are REAL differencesThere are REAL differences
SaltSaltvsvs
FreshFresh
AtelectasisAtelectasis
Aspiration leads to
collapse of the alveoli due to loss
of surfactant and
pulmonary edema
normal
alveoli
surfactant
collapsed alveoli
Pulmonary EdemaPulmonary Edema
capillary
Interstitial fluid shift
AlveoliO2
CO2
Reduced perfussion
O2 CO2
Potential Fresh Water DamagePotential Fresh Water Damage
HypoxiaHypoxia AtelectasisAtelectasis Pathogenic bacteria and impurities lethalPathogenic bacteria and impurities lethal Produces greater long-term damage due Produces greater long-term damage due
to salt in pulmonary edemato salt in pulmonary edema
DrowningDrowning
Potential Salt Water DamagePotential Salt Water Damage Hypovolemia if large amounts swallowedHypovolemia if large amounts swallowed HypertonicHypertonic
Elevation of Na, Cl and K, Elevation of Na, Cl and K, decrease blood volumedecrease blood volume
Salt water is 2 times as lethalSalt water is 2 times as lethal
Near DrowningNear DrowningMulti-Organ EffectsMulti-Organ Effects
Hypoxic/ischemic cerebral injuryHypoxic/ischemic cerebral injury Fluid overloadFluid overload Pulmonary injuryPulmonary injury HypothermiaHypothermia
ASPHYXIAASPHYXIA
Pulmonary SystemPulmonary System 1. secondary apnea,1. secondary apnea, aspirationaspiration 2. hypercapnea2. hypercapnea
Central Nervous SystemCentral Nervous System1. anoxic damage1. anoxic damage2. defective autoregulation2. defective autoregulation3. cerebral edema 3. cerebral edema 4. increased ICP4. increased ICP
RenalRenal1. acute tubular necrosis1. acute tubular necrosis2. acute cortical necrosis2. acute cortical necrosis
CardiacCardiac1. myocardial ischemia1. myocardial ischemia2. fibrillation2. fibrillation
AsphyxiaAsphyxia
low BPlow BP
HypothermiaHypothermia CARDIACCARDIAC dysrhythmdysrhythmiaia
VASODILATIONVASODILATIONdecreased ICPdecreased ICPdecreased BPdecreased BP
CENTRALCENTRALNERVOUSNERVOUS1. reduced 1. reduced metabolismmetabolism2. reduced ICP2. reduced ICP3. ?protection?3. ?protection?4. may produce 4. may produce picturepicture of clinical deathof clinical death
DEATHDEATH
RENAL RENAL FAILUREFAILURE
Rogers, Pediatric Critical CareRogers, Pediatric Critical Care
WATER OVERLOADWATER OVERLOAD Pulmonary SystemPulmonary System 1. alveolar fluid1. alveolar fluid 2. “ARDS”2. “ARDS” 3. hypoventilation3. hypoventilation
Central Nervous SystemCentral Nervous System1. cerebral edema1. cerebral edema2. intracranial hypertension2. intracranial hypertension
Dilution EffectsDilution Effects1. hypokalemia1. hypokalemia2. hemodilution2. hemodilution3. hemolysis3. hemolysis
GastrointestinalGastrointestinal1. gastric distension1. gastric distension2. vomiting, aspiration2. vomiting, aspiration3. ileus3. ileus
Water OverloadWater Overload
Near DrowningNear Drowning Multi-Organ EffectsMulti-Organ Effects
Cerebral Cerebral hypoxia is the hypoxia is the final common final common pathway in all pathway in all drowning drowning victimsvictims
Near DrowningNear DrowningCNS InjuryCNS Injury
With significant hypoxia can have Lance-With significant hypoxia can have Lance-Adams syndrome Adams syndrome Post hypoxic (action) myoclonusPost hypoxic (action) myoclonus Often mistaken for seizuresOften mistaken for seizures Happens more often when coming out of Happens more often when coming out of
sedationsedation Must be differentiated from myoclonic status Must be differentiated from myoclonic status
which has poor prognosis which has poor prognosis
Near DrowningNear DrowningPulmonary InjuryPulmonary Injury
Aspiration as little as 1-3 cc/kg can cause Aspiration as little as 1-3 cc/kg can cause significant effect on gas exchangesignificant effect on gas exchange Increased permeabilityIncreased permeability Exudation of proteinaceous material in alveoliExudation of proteinaceous material in alveoli Pulmonary edemaPulmonary edema decreased compliancedecreased compliance
Near DrowningNear DrowningPulmonary Injury:Pulmonary Injury:
Fresh Water vs. Salt WaterFresh Water vs. Salt Water Theoretical changes not supported clinicallyTheoretical changes not supported clinically
Salt water: hypertonic pulmonary edemaSalt water: hypertonic pulmonary edema Fresh water: plasma hypervolemia, hyponatremiaFresh water: plasma hypervolemia, hyponatremia Unless in Dead SeaUnless in Dead Sea
Humans (most aspirate 3-4cc/kg) Humans (most aspirate 3-4cc/kg) Aspirate > 20cc/ kg before significant electrolyte Aspirate > 20cc/ kg before significant electrolyte
changeschanges Aspirate > 11cc/kg before fluid changesAspirate > 11cc/kg before fluid changes
The Bottom LineThe Bottom LineFresh Water and Salt WaterFresh Water and Salt Water
Both forms wash out surfactantBoth forms wash out surfactant Damaged alveolar basement Damaged alveolar basement
membranemembrane Pulmonary edemaPulmonary edema ARDSARDS
Labs & testsLabs & tests
Very mild electrolyte changesVery mild electrolyte changes Moderate leukocytosisModerate leukocytosis Hct and Hgb usually normal Hct and Hgb usually normal
initallyinitally Fresh water aspiration, Fresh water aspiration,
the Hct may fall slightly in the Hct may fall slightly in the first 24 hrs due to the first 24 hrs due to hemolysishemolysis
Increase in free Hgb Increase in free Hgb without a change in Hct is without a change in Hct is commoncommon
DIC occasionallyDIC occasionally ABG – metabolic acidosis & ABG – metabolic acidosis &
hypoxemiahypoxemia
EKGEKGSinus tachycardia & nonspecific ST-Sinus tachycardia & nonspecific ST-segment and T-wave changessegment and T-wave changes
Reverts to normal within hoursReverts to normal within hoursOminous - ventricular arrhythmias, Ominous - ventricular arrhythmias, complete heart blockcomplete heart block
CXRCXRMay be normal initially despite severe May be normal initially despite severe respiratory disturbancesrespiratory disturbancesPatchy infiltratesPatchy infiltratesPulmonary edemaPulmonary edema
Essential First Aid ManagementEssential First Aid Management
ConsciousConscious UnconsciousUnconscious
Evaluate forEvaluate for CPR (prolonged)CPR (prolonged)Aspiration Aspiration 100% oxygen100% oxygen
NONO YESYES
ObserveObserve 100% oxygen100% oxygen transfer to transfer to hospitalhospital
TreatmentTreatmentTransportTransport
Continue CPRContinue CPR Establish airwayEstablish airway Remove wet clothesRemove wet clothes Hospital evaluationHospital evaluation
Immediate hospital managementImmediate hospital management
Assess and manage ABCAssess and manage ABC 100% oxygen100% oxygen Pulse oximetry (watch for false readings caused Pulse oximetry (watch for false readings caused
by peripheral shutdown and acidosis)by peripheral shutdown and acidosis) ABGs, FBC, U&EABGs, FBC, U&E CXRCXR ObservationObservation Management of associated hypothermiaManagement of associated hypothermia
TreatmentTreatmentEmergency DepartmentEmergency Department
Continue established therapiesContinue established therapies History, physical, labsHistory, physical, labs Admit if: CNS or respiratory symptomsAdmit if: CNS or respiratory symptoms Observe in ED for minimum 4-6 hours if:Observe in ED for minimum 4-6 hours if:
Submersion > 1 min.Submersion > 1 min. Cyanosis on extractionCyanosis on extraction CPR requiredCPR required
Predicting Ability for ED DischargePredicting Ability for ED Discharge
Several studies support selected ED Several studies support selected ED dischargedischarge
Child can safely be discharged home if at Child can safely be discharged home if at 6 hours after ED presentation:6 hours after ED presentation: GCS GCS >> 13 13 Normal physical exam/respiratory effortNormal physical exam/respiratory effort Room air pulse oximetry oxygen saturation > Room air pulse oximetry oxygen saturation >
95%95%
The problem with looking wellThe problem with looking well
Aspiration of water can cause late Aspiration of water can cause late complications:complications:
Neurogenic pulmonary oedema, Neurogenic pulmonary oedema, Pneumonia, SIRS, DIC, Haemolysis, Pneumonia, SIRS, DIC, Haemolysis, Hepatic & renal failure, bowel necrosisHepatic & renal failure, bowel necrosis
Plus complications of hypothermiaPlus complications of hypothermia
ICU Management StrategiesICU Management StrategiesIntubation/VentilationIntubation/Ventilation
SpOSpO22 < 90% on FIO < 90% on FIO22 > 0.6 > 0.6
PaCOPaCO2 2 > 50 with pH < 7.3> 50 with pH < 7.3
Increased work of breathingIncreased work of breathing Abnormal CNS examAbnormal CNS exam
IndicationsIndications
ICU Management StrategiesICU Management StrategiesRespiratoryRespiratory
Oxygenate - avoid hypoxemiaOxygenate - avoid hypoxemia Ventilate - avoid significant Ventilate - avoid significant
hyperventilationhyperventilation PEEP may be beneficial but is not PEEP may be beneficial but is not
prophylacticprophylactic Exogenous surfactantExogenous surfactant
Management StrategiesManagement StrategiesCardiovascularCardiovascular
Re-warming ( to a degree ? benefit Re-warming ( to a degree ? benefit hypothermia)hypothermia) LOC 34 CLOC 34 C Pupils dialate 30 CPupils dialate 30 C V Fib 28 CV Fib 28 C EEG iso-electric 20CEEG iso-electric 20C
CBF decrease 6-7% per degree C CBF decrease 6-7% per degree C dropdrop
Management StrategiesManagement StrategiesCentral Nervous SystemCentral Nervous System
Protect against 2Protect against 20 0 injuryinjury Perfuse it or lose it !!Perfuse it or lose it !!
ICP monitoring not beneficial or ICP monitoring not beneficial or recommendedrecommended
Some still monitor if:Some still monitor if: Successful CPR followed by comaSuccessful CPR followed by coma Sudden, unexplaind deteriorationSudden, unexplaind deterioration
Management StrategiesManagement StrategiesCentral Nervous SystemCentral Nervous System
ICP monitoring may not change ICP monitoring may not change outcome, just predict itoutcome, just predict it
Low ICP Better outcomeLow ICP Better outcome High ICP Poor outcomeHigh ICP Poor outcome
ICU Management StrategiesICU Management Strategies
Antibiotics - no benefit of prophylaxis, Antibiotics - no benefit of prophylaxis, may increase super-infectionmay increase super-infection
Fulminant Strep pneumoniae sepsis Fulminant Strep pneumoniae sepsis has been described after severe has been described after severe submersionsubmersion
Steroids - no demonstrated benefitSteroids - no demonstrated benefit
Other IssuesOther Issues
SURVIVE OR NOT
SURVIVE OR NOT
Will the child die?Will the child die?
Bad prognostic indicatorsBad prognostic indicators
Submerged >10 minSubmerged >10 min Time till BLS >10 minTime till BLS >10 min CPR >25 minCPR >25 min Initial GCS <5Initial GCS <5
Age <3 yearsAge <3 yearsCPR in ERCPR in ERInitial ABG pH <7.1Initial ABG pH <7.1Initial core temp <33oInitial core temp <33o
Neurologic prognosisNeurologic prognosis
Absence of spontaneous respiration is an Absence of spontaneous respiration is an ominous sign associated with severe ominous sign associated with severe neurologic sequelaeneurologic sequelae
Permanent neurologic sequelae persist in Permanent neurologic sequelae persist in ~20% of victims who present comatose~20% of victims who present comatose Minimal brain dysfunction, spastic Minimal brain dysfunction, spastic
quadriplegia, extrapyramidal syndromes, optic quadriplegia, extrapyramidal syndromes, optic and cerebral atrophy, and peripheral and cerebral atrophy, and peripheral neuromuscular damageneuromuscular damage
Near Drowning Near Drowning The Best Approach Therefore:The Best Approach Therefore:
P P revention ! revention ! P P revention !revention !P P revention !revention !
Near Drowning Near Drowning Keeping Your Child SafeKeeping Your Child Safe
Never leave a child alone in or Never leave a child alone in or near water, even for a minutenear water, even for a minute
Limit pool access.Limit pool access.Remove potential hazardsRemove potential hazards
Children with Epilepsy: Children with Epilepsy: Safety RecommendationsSafety Recommendations
Child can swim in lifeguard-supervised Child can swim in lifeguard-supervised swimming pool - no open waterswimming pool - no open water
Older child should shower in a non-glass Older child should shower in a non-glass cubicle - no bathcubicle - no bath
Leave bathroom unlockedLeave bathroom unlocked Supervision!Supervision!
Near DrowningNear DrowningSwimming Pool LoreSwimming Pool Lore
My Child is My Child is “Water Safe” “Water Safe” because he/she has taken because he/she has taken swimming lessonsswimming lessons..
Near DrowningNear DrowningKeeping Your Child SafeKeeping Your Child Safe
Learn CPRLearn CPRUse approved personal Use approved personal
flotation devicesflotation devicesTeach safe water behaviorTeach safe water behavior
RecommendationsRecommendations
Pre-hospital resuscitation, including Pre-hospital resuscitation, including early intubation, ventilation, vascular early intubation, ventilation, vascular access, and administration of access, and administration of advanced life support medicationsadvanced life support medications
Continued resuscitation and Continued resuscitation and stabilization in the EDstabilization in the ED
RecommendationsRecommendations Full supportive care in the ICU for a Full supportive care in the ICU for a
minimum of 48 hrsminimum of 48 hrs Consider withdrawal of support if no Consider withdrawal of support if no
neurologic improvement is detected after neurologic improvement is detected after 48 hours48 hours Ancillary testing such as brainstem Ancillary testing such as brainstem
evoked responses, EEG, and MRI (not evoked responses, EEG, and MRI (not CT) may prove helpful to corroborate CT) may prove helpful to corroborate the neurologic examinationthe neurologic examination