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Drowning and electrical injuries


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prepared by Al Yaqdhan Hamdan Alatbi
Senior clerkship medical student SQUH cohort 2007

Published in: Health & Medicine
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Drowning and electrical injuries

  1. 1. Done by: Al-Yaqdhan Al-Atbi Senior clerkship medical student SQUH
  2. 2. Outline  Outline the principles of Pre-hospital and ED management and disposition of submersion injury patients.  Differentiate between different mechanisms of Electrical injuries(AC,DC,lightening)  Describe the basic principles of management and disposition of electrical injury patients
  3. 3.  Drowning: is death from asphyxia due to suffocation caused by water entering the lungs and preventing the absorption of oxygen leading to cerebral hypoxia.  World Congress on Drowning in 2002 and subsequently the WHO define drowning as:”  the process of experiencing respiratory impairment from submersion/immersion in liquid”  Near drowning is the survival of a drowning event involving unconsciousness or water inhalation and can lead to serious secondary complications, including death, after the event
  4. 4.  According to the WHO, drowning is the 3rd leading cause of unintentional injury death worldwide, accounting for 7% of all injury related deaths.  96% of these deaths occurring in low- and middle- income countries  In many countries, drowning is one of the leading causes of death for children under 12 years old.  Drowning occurs more frequently in males and the young
  5. 5.
  6. 6. 90% of drownings take place in freshwater (rivers, lakes and swimming pools) and 10% in seawater  Primary causes:  Infants:  bathtubs or buckets of water  Most of these victims drown during a brief (< 5 min) lapse in adult supervision.  Children aged 1-5 years  Residential swimming pools are the most common venue  no physical barrier between the pool and the home  Young adults aged 15-19 years  Young adults typically drown in ponds, lakes, rivers, and oceans  Alcohol or drugs
  7. 7.  Secondary causes:  Seizure  (MI) or syncopal episode  Major depression/suicide  Anxiety/panic disorder  Diabetes, hypoglycemia  Water sports hazards  Substance abuse  Cervical spine injury and head trauma associated with surfing, water skiing, and jet skiing  Scuba diving accidents and other injuries (eg, bites, stings, lacerations)  Natural disasters
  8. 8.  Wet Drowning:  the person has inhaled water which interferes with respiration and causes the circulatory system to collapse.  Dry Drowning:  Muscle spasms in the area around the voice box block the airway. No water enters the lungs.  Lead to nigative pressure pulmonary edema (forced inspiration against closed glottis) increase capillary endothelium permeability occur with surfactant disturbance ARDS or acute lung injury  often due to immersion in cold water.  Around 10% of drownings are dry drownings.
  9. 9. Case scenario  A group of teenagers was swimming at the lake, when one of the boys failed to surface after diving off platform. He was quickly found and rescued by another swimmer from the lake bottom.  What should you do???
  10. 10. Pre hospital  On scene:  In the patient with an altered mental status, the airway should be checked for foreign material and vomitus. Debris visible in the oropharynx should be removed  Immediate Rescue Breathing (even before out of water)…  The abdominal thrust (Heimlich) maneuver has not been shown to be effective in removing aspirated water; in addition, it delays the start of resuscitation and risks causing the patient to vomit and aspirate. In any event, ventilation is achieved even if fluid is present in the lungs. Remove wet clothing, passive external rewarming (Hypothermia!)  CPR (pulse check)   Supplemental oxygen, 100%, should be administered as soon as available. Immediately place the patient on 100% oxygen by mask  Consider trauma: C-spine precautions
  11. 11.  The patient noted to be apneic and CPR was initiated by one of the bystanders.  After paramedics arrived, patient noted to have spontaneous shallow respirations, weak palpable pulse, GCS score of 7=(E1,V2, M4).  The paramedics intubate him and transfer him to your facility  In ED patient vitals was BP 110/70, pulse 70/min, RR 12/min, temp 35.6 C, GCS= 6 (E1,V1,M4), What to do?? SpO2 92% on 100% FiO2
  12. 12. Emergency Department (ED):     Initial evaluation: ABCDEs and C-spine stabilization Place the patient on monitors Establish vascular access Warm IV NS and warm adjuncts (heating blankets, overhead warmer)  O2 supplementation  Intubation and mechanical ventilation  Careful examination including a trauma survey.  Broncoscopy may be indicated in selected cases  Cardiac arrythmias should be corrected  Note: Patients with severe hypothermia may appear dead because of profound bradycardia and vasoconstriction. Resuscitation should continue while aggressive attempts are made to restore normal body temperature
  13. 13. Investigations:  ECG: for dysrhythmias  ABG  Labs: electrolytes, renal function, CBC, glucose although usually N  CXR
  14. 14.  What are the complications associated with this condition??
  15. 15. Complications  Hypoxic- ischemic eveents affecting brain, lung and      heart. Hypoxic encephalopathy Noncardiogenic pulmonary edema Dysarrythmia Respiratory and metabolic acidosis Hemodilution  Late complications:     Pneumonia Acute lung injury ARDS empyema
  16. 16. In all cases of wet Drowning there is O2 deprivation, but also presence of water in the lungs have direct effect on blood chemistry
  17. 17. • Freshwater (isotonic)  the pulmonary circulation by osmosis (dilution of blood)  haemolysis (bursting of red blood cells)  elevation of plasma K+ level and depression of Na+ level  alter the electrical activity of the heart  ventricular fibrillation. • animal experiments : capable to cause cardiac arrest 2 to 3 minutes. • Sea water (hypertonic to blood , more salty)  Osmosis will instead pull water from the bloodstream into the lungs, thickening the blood  requires more work from the heart  cardiac arrest. • animal experiments : capable to cause cardiac arrest 8 to 10 minutes.
  18. 18.  Mammalian diving reflex:  is a reflex in mammals which optimizes respiration to allow staying underwater for extended periods of time  Strong in aquatic mammals: seals, otters, dolphins, etc  Weak in human  Triggered only by diving in cold water <21C  Three principle effects:  Bradycardia  Peripheral vasoconstriction  Blood shift: major vital organs
  19. 19.  Breathing reflex:  Person submerge holding breath lead to hypoxia and hypercapnia effect of Co2 in respiratory center  breathing hold breakpoint (PaCO2=55 mmHg)  The breath-hold break point can be suppressed or delayed either intentionally or unintentionally
  20. 20. Submersion Injuries  General: 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
  21. 21. Submersion Injuries  CVS: dysrhythmias  CNS: initial hypoxic injury or secondary reperfusion injury with resuscitation  Renal: ARF due to lactic acidosis, prolonged hypoperfusion, rhabdo
  22. 22. Who can go home?  Asymptomatic on presentation  Maintains normal room air sat  No CXR or ABG abnormalities …… D/C after 8 hour observation Do we admit this patient????
  23. 23. Prevention  Infants  Parental vigilance  Toddler  Pool fencing  Adolescent/Young Adult  Control Alcohol/Drug Use  Swimming lessons  Elderly  Same as infant/toddler  Precautions for water safety     Fence pools Supervise children Do not mix alcohol and water activities Use personal flotation devices and life preservers
  24. 24. ELECTRICAL INJURIES •Differentiate between different mechanisms of Electrical injuries(AC,DC,lightening) •Describe the basic principles of management and disposition of electrical injury patients
  25. 25. Electricity:  Electricity is simply the flow of electrons.  Ohm’s law: I = V/R  The most harmful effects of electricity on the body are thermal Heat = (amperage)2 * resistance *time •Because amperage is squared, it contributes the most to tissue injury. • In real accidents, the amperage is often unknown. Therefore, we use voltage as an approximate indicator because high voltages are usually associated with high amperages.
  26. 26.  Electrical injuries present with a wide spectrum of damage, from superficial skin burn to multisystem injury and death.  Electricity-induced injuries are common and most are preventable.  Electrical current type is either alternating current (AC) or direct current (DC).
  27. 27. Alternating current (AC)  Bidirectional electrical flow that reverses direction in a sine wave pattern forward to backward direction.  AC current can be low voltage or high voltage.  Low voltage (< 1000 V) is typically household AC current that ranges in severity from minor injury to significant damage and death.  High voltage (> 1000 V) is most often related to occupational exposure and is associated with deep tissue damage and higher morbidity and mortality.
  28. 28. Direct current (DC)  Unidirectional electrical flow (eg, that associated with lightning, batteries, thermocouple, and automotive electrical systems).  It is more likely to cause a single intense muscle contraction and asystole.
  29. 29. Lightning  Differs from other high-voltage electrical shock in that lightning is massive DC current of millions of volts lasting a very brief duration (a small fraction of a second).  Occurs when electrical difference between a thundercloud and the ground overcomes the insulating properties of the surrounding air  Current rises to a peak in about 2 µsec
  30. 30. HIGH-VOLTAGE ELECTRICAL INJURIES VS LIGHTNING HIGH-VOLTAGE ELECTRICAL INJURIES LIGHTNING Duration Prolong contact Instantaneous Energy 1,000 to 10,000 volts 1 billion volts Current AC DC Cardiac effect ventricular fibrillation asystole Burns deep (may appear benign or superficial) Minor and superficial Urinary failure myoglobinuric rare Fasciotomy Rarely indicated common and early
  31. 31.  You are in the ED when two patient arrive by paramedics. By report, two men in their twenties were victims of lightning injury while playing football.  Eyewitnesses at the scene report that the victims were standing several feet apart, when one of the men was struck directly by the lightning that result in both men immediately falling to the ground and becoming unconscious.
  32. 32. Emergency treatment:  Rescuer should be cautious when treating victims  Persons who have been struck by lightning should be        treated as trauma patient. Unlike other trauma, priority is givin people who appear dead Assess and stabilize the patient (ABCDE) close attention to C-spine immobilization Continuous vitals monitoring At least 1 large-bore IV crytalloid should be givin VT, VF, and asystole standard ACLS protocols Fractures and dislocations reduce and splinted
  33. 33. Patient Evaluation  History and physical examination  Pulse oximetry, vitals monitor  Laberatory studies:  Urinalysis: to check myoglobinuria  CBC, Serum electrolytes, cardiac enzymes should be obtained even if asymptomatic  CT scan indicated in all patient with severe lightning injury and those with abnormal neurological examination
  34. 34.  O/E  First victim:  intubated by the paramedics  was found pulseless at the scene and CPR was initiated  extensive soft tissue burns over his back  No palpable pulse and ECG showed VF  Second victim:  remain unconscious for a several minutes  Pulse 80/min, BP130/80mmHg. RR 18/min, GCS 13/15  No identifiable external sign of injury
  35. 35. Mechanisms of Injury  Direct effect of electrical current  Thermal burns  Mechanical Trauma  Post-trauma sequelae
  36. 36.  The extent of damage depends on the following factors:  Duration of exposure;  Voltage (high or low)  Current type,  Standard household electricity is AC. Electricity in batteries and lightning is DC. Low-frequency (50- to 60-Hz) AC can be more dangerous than similar levels of DC because the alternating current fluctuations can result in ventricular fibrillation.  Tissue resistance,  Moisture,  Dry skin has high resistance, but sweaty or wet skin has much less resistance.  Pathway  Associated trauma  Comorbidities.
  37. 37. Thermal (Burn) Injuries  Type & extent of injury depends on current intensity (I)  High voltages: Severe electrical burns, because only a fraction of a second of current flow is necessary for severe damage to occur.  Low voltage: Burns are less common, because lowvoltage contact produces little heat energy in the skin and other tissues.  Resistance varies significantly between tissues:  Tissues with high R (e.g., bone), generate more heat, resulting in osteonecrosis and deep tissue periosteal burns, especially surrounding long bones
  38. 38. Mechanical Trauma  Trauma can result from fall or muscle contraction  Tetanic Contractions :  Electric current can induce sustained muscular contraction or tetany.  The overall effect varies according to type (AC or DC), frequency, voltage, and extent of contact.  E.g. AC current flowing through the forearm can cause flexor tetany of the fingers and forearm that overpowers actions of the extensor muscles.  Forceful muscle contractions can cause fractures and joint dislocations, especially around the shoulders.  Current flow through the trunk and legs may cause brief, but strong, opisthotonic (arching) posturing and leg movements
  39. 39. Post-trauma sequelae  Crush injury syndrome (rhabdomyolysis, myoglobinuria)  Multi-organ ischemic injury 2o/2 vascular coagulation or dissection  Hypovolemic shock 2o/2 massive 3rd spacing
  40. 40. Disposition  Victims of electrical injury with no LOC, or physical finding and have normal ECG can be safely discharged home  Indications for admission :  High voltage > 600 V  Symptoms suggestive of systematic injury  Evidence of neurologic or vascular injury to a digit or      extremity Burns with subcutaneous tissue damage Arrhthymias Pregnancy Associated injuries requiring admission Comorbid diseases (Cardiac, renal, neurologic)
  41. 41. Refference  Tintinali, Emergency Medicine Manual Book, 6th     edition. Joseph J. Mistovich • Keith J. Karren, Prehospital Emergency Care, Ninth Edition, 2010 by Pearson Education, Inc., All rights reserved.. Markovchick. VN et al. Emergancy medicine secrets. Fifth edition Simon T, Takenake B. Case Files emergancy medicine. E-medicine website. ”lightning”  Plantz SH & Wipfler EJ. NMS, Emergancy Medicine. Second edition. Lippincott Williams and Wilkins. 2007  Romano M, Sauve J etal; Emergency Medicine. Toranto Notes2011
  42. 42. THANK YOU