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Drowning
Aka: Drowning, Near-drowning, Nonfatal Drowning, Fatal Drowning
- Definition
- Drowning (WHO Definition)
- Respiratory Impairment from submersion or immersion in liquid
- Further classified into fatal or nonfatal (replaces Near-drowning)
- Avoid antiquated terms such as dry Drowning (laryngospasm, but no fluid aspirated into lungs)
- Epidemiology
- Deaths per year
- Worldwide: 140,000-300,000
- United States: 4,000 to 8,000
- Incidence peaks May to August in United States
- Males account for 80% of Drowning deaths
- Most cases in age <14 years old in the United States
- Age 1-4 most commonly drown in home swimming pools
- Teens over age 15 years most commonly drown in rivers, lakes or ocean
- Causes
- Home pools (50% of Drowning cases in United States)
- Age under 5 years accounts for 90% of cases
- Bathtub
- Second most common site for preschool Drowning cases
- Majority ages 7 to 15 months old
- Occupations
- Fishing industry (especially Alaska)
- Personal Water Craft (e.g. Seadoo)
- Relative Risk (compared with other boats): 8.5
- References
- Branche (1997) JAMA 278(8):663-5 [PubMed]
- Alcohol and Illicit Drugs
- Involved in over 50% adolescent Drowning cases
- Developmental or neurologic Impairment
- Epilepsy
- Rural Hazards
- Ponds
- Ditches
- Old septic tanks
- Water filled buckets
- Accounts for 24% of preschool Drowning cases
- Toddlers unable to right themselves
- Physical Abuse
- Accounts for 8% of childhood Drowning cases
- References
- Gillenwater (1996) Arch Pediatr Adolesc Med 150:298 [PubMed]
- Risk Factors
- Home pool childproofing lacking
- Unable to swim
- Adult supervision lacking
- No life jacket use
- Alcohol or drug use
- Risk taking behavior
- Cardiac events
- Seizure disorder
- Developmental Disorder
- Mechanism
- Patient struggles to stay above water and hold breath as they submerge
- Ultimately a breath is taken with subsequent laryngospasm or aspiration
- Aspirated water disrupts alveolar-capillary membrane
- Results in Atelectasis, surfactant loss and Ventilation-Perfusion Mismatch (V-Q Mismatch)
- Causes severe hemorrhagic Pulmonary Edema and bronchospasm
- Asphyxia leads to Hypoxemia and Metabolic Acidosis
- Cardiac rhythm degenerates over minutes from Tachycardia to Bradycardia to PEA to Asystole
- Dry Drownings on autopsy (no lung water): 10-20%
- Small-moderate amount water aspirated (<22 ml/kg): 85%
- Freshwater and Saltwater Drownings are treated the same
- Both fresh and saltwater in alveoli cause surfactant dysfunction
- Complications
- Adult Respiratory Distress Syndrome
- Persistent anoxic-ischemic encephalopathy
- Aspiration Pneumonia, Lung Abscess, empyema
- Especially if water contaminated
- Pneumothorax, Barotrauma from high Ventilatory pressure
- Traumatic Myoglobinuria or Hemoglobinuria
- Renal Failure (Acute Tubular Necrosis)
- Coagulopathy (associated with Hypothermia)
- Sepsis
- Hypothermia
- Hyperglycemia (from Catecholamine release)
- Seizures
- Evaluation: First Responders
- Move patient immediately to land and position supine
- In-water Resuscitation (ventilations) only if rescuer is skilled in that technique
- Start bystander CPR without delay
- Outcomes are best with immediate initiation of high quality CPR
- Apply AED when available (and on a relatively dry surface)
- Remove wet clothing and apply dry towels, blankets and other methods of rewarming
- Evaluation: No response to verbal or tactile stimuli (prehospital EMS)
- Ventilations are performed first instead of compressions (ABC instead of CAB)
- Open airway and check for ventilations
- No breathing
- Give 5 initial breaths
- Check carotid pulse
- Breathing
- Lung auscultation (see protocol below)
- Place in recovery position (left lateral decubitus)
- Pulse absent
- Submersion >1 hour or signs of death (Death)
- Survival probability: 0%
- Pronounce patient and cease efforts
- Submersion <1 hour and no signs of death (Grade 6)
- Initiate CPR with high quality Chest Compressions (100-120/min)
- Apply AED or Defibrillator pads when available (most commonly in Asystole or PEA)
- Move to Grade 5 or 4 management (if ROSC achieved)
- Survival probability: 7-12%
- Pulse present (Grade 5)
- Rescue Breathing until return of spontaneous ventilation or Mechanical Ventilation
- Chest Compressions (and epinephine, Atropine) if Heart Rate <60/min in a young child (Unstable Bradycardia)
- Move to grade 4 management
- Admit to medical ICU
- Survival probability: 56-69%
- Evaluation: Responds to verbal or tactile stimuli (prehospital EMS)
- Abnormal breath sounds
- Rales in all pulmonary fields
- General management
- High Flow Oxygen via Face Mask
- Intubate for GCS 8 or less, Respiratory Failure or other Advanced Airway indications
- Admit to medical ICU
- Hypotension or shock (Grade 4)
- Risk of delayed respiratory arrest
- Fluid Resuscitation with crystalloid and consider Vasopressors
- Survival probability: 78-82%
- Normal Blood Pressure (Grade 3)
- Survival probability: 95-96%
- Rales in some pulmonary fields (Grade 2)
- Low Flow Oxygen
- Transfer to emergency department
- Survival probability: 99%
- Normal breath sounds (94% of lifeguard rescues)
- Cough (Grade 1)
- Further evaluation as needed
- Survival probability: 100%
- No cough (Rescue)
- No comorbid conditions and asymptomatic
- May be discharge from accident scene
- Imaging
- Chest XRay
- Initial XRay is typically normal (ARDS findings delayed)
- Diagnostics
- Electrocardiogram (EKG)
- Labs
- Arterial Blood Gas
- Complete Blood Count
- Comprehensive Metabolic Panel (rarely abnormal)
- Coagulation Studies (INR, PTT, rarely abnormal)
- Blood Alcohol Level (if indicated)
- Urine Drug Screen (if indicated)
- Pregnancy Test (if indicated)
- Management: Initial
- Accident site
- Do NOT clear airway of aspirated water
- Delays ventilation
- Use Heimlich/Abdominal thrust ONLY IF obstruction
- Cervical Spine precautions
- Controversial unless diving or other injury with suspected C-Spine Injury
- Cervical Spine injuries occur in <1% of Drowning cases
- Rescue Breathing and CPR
- Ventilation is paramount and should be started while still in water (if skilled in technique)
- Start with 5 ventilations and then every 6-8 seconds until on land
- Chest Compressions obviously are delayed until on land at which time initiate 2 breaths per CPR cycle
- Keep patient horizontal to maximize brain perfusion
- Initial ACLS management
- ACLS protocol
- Respiratory management is paramount
- Intubation indications
- Apnea
- PaO2 <60 mmHg or Oxygen Saturation <90% despite Oxygen Supplementation
- PaCO2 >50 mmHg
- Unconscious patient or neurologic deterioration
- Unable to protect airway
- Non-Invasive Positive Pressure Ventilation for conscious patients
- Move to intubation if not improving in first 10-30 minutes
- C-Spine precaution indications
- Altered Level of Consciousness or intoxicated
- Head, face, neck Trauma findings
- History consistent with neck injury (e.g. diving or boating accident, fall from height)
- Observation for Vomiting and aspiration risk
- Occurs in 30-85% of Drowning victims who swallow large water volumes
- Intravenous Fluids
- Persistent Hypotension is associated with worse outcomes
- Hypothermia
- Cold water Drownings are protective of neurologic status
- Drowning victims are "not dead unless warm and dead"
- Cerebral oxygen (and ATP) consumption drops by 5% per every 1 C below 37C
- Cerebral oxygen (and ATP) consumption drops 50% when core Temperature 27C
- Core Temperature of 27C (10C drop from 37C) doubles brain survival time
- Mild Hypothermia (Brief immersion in warm water with Body Temp 32-35C or 89.6-95F)
- Initiate rewarming en route to facility
- Moderate to Severe Hypothermia (T <32C or 89.6F) - Most cases
- See Hypothermia Management
- Passive Rewarming may be started in field
- Initiate active rewarming at medical facility
- Empiric antibiotics are not typically indicated
- Consider if grossly contaminated water
- Gram Stain and culture directed antibiotics are preferred over empiric, prophylactic antibiotics
- Medical facility management
- Continue ACLS protocol
- Reevaluate airway and consider intubation (see indications above)
- Glasgow Coma Scale
- Nasogastric Tube (decompress swallowed water)
- Evaluate C-Spine for suspected injury (if high risk mechanism such as diving)
- Freshwater and Saltwater Drownings are treated the same
- Core Rewarming (for severe Hypothermia)
- Avoid drugs or stimuli that can trigger Ventricular Fibrillation
- Administer warm humidified oxygen endotracheally
- Administer warm fluid by central IV
- Peritoneal or Chest Tube lavage
- Esophageal rewarming tube
- Cardiopulmonary bypass or Extracorporeal Membrane Oxygenation (ECMO)
- Continue Resuscitation efforts until core Temperature 34-35C (or 93.2 to 95C)
- Management: Disposition
- Criteria for early discharge from ED after 8 hours observation (Grade 1, benign cases only)
- Children and young adults AND
- Normal age adjusted Vital Signs and examination including Oxygen Saturation >94% AND
- No symptoms AND
- No preexisting Neurologic or cardiopulmonary disease AND
- GCS 14 or 15
- Criteria for routine hospital ward observation for 24 hours
- Patients with minimal symptoms (mild cough) AND
- Normal Oxygen Saturation
- Criteria for ICU admission
- Above criteria not met
- Any signs of respiratory distress
- References
- Brennan (2018) Am J Emerg Med 36(9):1619-1623+PMID:29452918 [PubMed]
- Shenoi (2017) Acad Emerg Med 24(12): 1491-500 [PubMed]
- Management: ICU
- Monitoring
- Continuous O2 Sats and frequent lung auscultation
- Urine Output
- Electrolytes and Glucose
- CXR
- ABG
- Specific Management stratagies
- Bronchospasm
- Inhaled Beta Agonists
- Pulmonary Edema from freshwater immersion
- Loop Diuretics
- Airway protection from aspiration as indicated
- Intubation
- Nasogastric suction
- Hypoxia
- CPAP
- Mechanical Ventilation indications
- pCO2, mental status, work of breathing
- Unstable patients require aggressive management
- Intubation and Mechanical Ventilation
- IV fluids and Pressors (Dopamine) for Hypotension
- Metabolic Acidosis
- Maximize oxygenation and fluid Resuscitation
- Sodium Bicarbonate ONLY for severe acidosis (<7.10)
- Hyperglycemia
- Pathophysiology
- Associated with Catecholamine release
- May worsen encephalopathy
- Management
- Insulin drip to lower Glucose <300 mg/dl
- Mental status depression
- Induced Therapeutic Hypothermia
- Controversial in Drowning due to lack of evidence and underwhelming outcomes
- Not proven effective in pediatric Cardiac Arrest (except in case reports)
- Evaluation
- Neuro status usually improves with Resuscitation
- If Mental status depression/Seizure continues:
- Consider CT Head (r/o Head Injury)
- Consider Alcohol and Illicit Drug testing
- Management Seizures
- Supportive care
- Prolonged Seizure
- Diazepam or Ativan (0.1 mg/kg)
- Consider Dilantin loading
- Complications: Multisystem organ dysfunction from Hypoxia and Hypoxemia (in order of frequency)
- Respiratory dysfunction due to aspiration (significant injury even for >1-3 ml/kg fluid aspirated)
- Acute Respiratory Distress Syndrome (ARDS)
- Pulmonary insufficiency
- Neurologic dysfunction
- Cerebral Edema
- Increased Intracranial Pressure
- Cognitive Impairment
- Cardiovascular dysfunction
- Arrhythmias
- Sinus Tachycardia
- Sinus Bradycardia
- Pulseless Electrical Activity (PEA)
- Asystole
- Hypothermia related EKG Abnormalities (e.g. Osborn Wave or J Wave)
- Other less frequent abnormalities
- Hepatic Dysfunction
- Hematologic Dysfunction
- Renal Dysfunction
- Prognosis
- Predictors of survival and good neurologic outcome
- Pulse and detectable Blood Pressure on admit
- Young age
- Early rescue breaths by life guards or rescuers while patient still in water (often not feasible)
- Hypothermia (Core temp <95F or 35C)
- See Hypothermia Management above
- Diving reflex to very cold water is protective
- Breath holding, Bradycardia, redistribution
- Protection depends on rapid onset Hypothermia
- Child submerged 66 min in ice cold water survived neurologically intact (case report)
- In at least one 2014 study, water Temperature did not impact survival (see Quan reference below)
- Submersion time
- Time 0-5 minutes: 90% survival without severe neurologic deficit
- Time 6-10 minutes: 44% survival without severe neurologic deficit
- Time 11-25 minutes: 12% survival without severe neurologic deficit
- Time >25 minutes: 0% survival without severe neurologic deficit
- Predictors of poor prognosis
- pH < 7.10
- GCS < 5
- Pupils fixed and dilated on admit
- Persistent acidosis and coma 4 hours after Resuscitation
- Time to basic life support >10 minutes
- Cardiac Arrest at any age
- Submersion for 6 minutes or longer (7.4% with good outcomes compared with 88% if <6 minutes)
- Water Temperature did not impact survival
- Quan (2014) Resuscitation 85(6):790-4 +PMID: 24607870 [PubMed]
- Resuscitation >25-30 minutes (even in children with cold water drowing)
- Kieboom (2015) BMJ 350:h418 [PubMed]
- Outcomes
- Children requiring PICU admit for near Drowning
- 30% mortality
- 10-30% severe brain injury (e.g. persistent vegetative state, spastic quadriplegia)
- Overall
- 92% non-Fatal Drowning survivors recover completely
- Prevention
- Avoid swimming under influence of Alcohol, Illicit Drug
- Alcohol is found in 30-70% of Fatal Drowning victims
- Even small amounts of Alcohol increase risk, and risk increases in relationship to amount consumed
- Never swim alone
- Swim in areas with lifeguards
- Rescues by lifeguards require medical attention in only 6% of cases and CPR in 0.5% of cases
- Home swimming pool safety
- Install drain covers, vacuum release systems and multiple drains to displace pressure
- Install rescue equipment around pool (reaching pole, life buoys, working telephone)
- Install fence around home swimming pool
- At least 5 feet high with vertical openings <4 inches, and <4 inch opening at ground level
- Fence completely encloses pool on 4 sides (not attached to house on one side)
- Self closing and lockable gate (latching mechanism at least 58 inches above ground)
- Fence should not be climbable (e.g. not chain link)
- All family members should learn to swim
- Learn Cardiopulmonary Resuscitation (CPR)
- Safe proof home for infants and toddlers
- Never leave infants unsupervised in bath (do not substitute bath stands for direct supervision)
- Avoid leaving standing water in buckets, containers
- Do NOT leave water in home plastic wading pools
- Water sport participants
- Practice standard boating safety
- Avoid Alcohol while operating vehicles
- Wear personal floatation devices (floatable, air-inflated aids are not a substitute)
- Open water precautions
- Rip currents (away from beach) should be countered by swimming parallel to current until cleared
- Swift currents under rocks or trees can trap swimmers
- References
- Griffith (1994) Patient Instructions
- Resources
- CDC Unintentional Drowning
- http://www.cdc.gov/HomeandRecreationalSafety/Water-Safety/waterinjuries-factsheet.html
- Personal floatation devices
- http://www.uscg.mil/hq/cg5/cg5214/pfdselection.asp
- References
- Long (2018) Crit Dec Emerg Med 32(9): 17-24
- Nordt, Spangler, Schmidt and Borghei in Herbert (2015) EM:Rap 15(7): 2-4
- Mott (2016) Am Fam Physician 93(7): 576-82 [PubMed]
- Szpilman (2012) N Engl J Med 366(22): 2012-2110 [PubMed]
- Thanel (1998) Postgrad Med 103(6):141-54 [PubMed]