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ELECTRICAL INJURIES

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Rami Khouzam, MD The Statue of Zeus at Olympia An enormous statue of the Greek father of gods, carved by the great sculptor Pheidias In his right hand a figure of ... – PowerPoint PPT presentation

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Title: ELECTRICAL INJURIES


1
THE CURSE OF ZEUS
Rami Khouzam, MD
2
The Statue of Zeus at Olympia
  • An enormous statue of the Greek father of gods,
    carved by the great sculptor Pheidias
  • In his right hand a figure of Victory made from
    ivory and gold. In his left hand, his scepter
    inlaid with all metals, and an eagle perched on
    the sceptre
  • The sandals of the god are made of gold, as is
    his robe
  • Pausanias the Greek (2nd century AD)

3
7 Wonders of the Ancient World
  • Today, archaeological evidence reveals some of
    the mysteries that surrounded the history of the
    Wonders for centuries
  • For their builders, the Seven Wonders were a
    celebration of religion, mythology, art, power,
    and science
  • For us, they reflect the ability of humans to
    change the surrounding landscape by building
    massive yet beautiful structures, one of which (
    the Pyramid) stood the test of time to this very
    day

4
Index Case
  • 42-year-old white male
  • No significant past medical hx. except x possible
    marijuana
  • Was working on a ladder 12 feet high
  • Electrocuted with 440 volts
  • Contact burns to bilateral hands
  • Cardioversion done 5 times

5
  • Prior to arrival to the hospital
  • SVT --gt Cardioversion x 5
  • Hypotension --gt Dopamine and Epinephrine drips
  • Intubated
  • Vitals on arrival
  • Pulse 101
  • BP 71/46
  • RR 24

6
  • PE (pertinent findings)
  • Neck in C-collar
  • Ears some blood behind Lt. tympanic membrane
  • Chest Bilateral crackles
  • Heart S1S2 RRR Few extra-beats, No m,g,r
  • Upper extremities 2nd 3rd degree burns on the
    palmar aspects of both hands

7
  • Labs
  • K 3.1, Cr 1.1
  • WBCs 27.8 ? 10.5
  • AST/ALT 63/54
  • ABGs 7.25/43.8/213.7/18.6/99.1
  • Lactic a 4.2
  • UDS methamphetamine

8
  • Trop 1.38 2.87 1.81
  • CK 989 2190
  • CKMB 19.4 17.2
  • CKMB index 2.0 0.8
  • Myoglobin gt 500 gt 500

9
  • Swan-Ganz
  • PCWP 19
  • PA 31/14
  • CVP 15
  • CO 16 / CI 11
  • SVR 335
  • MAP 80
  • CXR
  • Interstitial alveolar pulmonary opacities
    centrally with relative sparing peripherally
  • consistent with pulmonary edema

10
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11
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12
  • TTE on admission
  • Mild eccentric LVH
  • LV systolic function was moderately to severely
    decreased
  • EF 25-30

13
  • Day 3
  • Levophed discontinued
  • Weaned off of the vent extubated
  • Blood culture MRSA
  • Day 8
  • Discharged home on pain meds antibiotics

14
  • TTE (prior to d/c)
  • Normal left ventricular systolic function
  • EF 65

15
The Hanging Gardens of Babylon
  • A palace with legendary gardens built on the
    banks of the Euphrates river by King
    Nebuchadnezzar II

16
ELECTRICAL INJURIES
  • Critical Care Medicine
  • Volume 30.Number 11.November 2002

17
  • Adults in workplace, children at home
  • Severity of injury depends on
  • Intensity of electrical current (voltage of
    source and resistance of victim)
  • Pathway through victims body
  • Duration of the contact with the source

18
  • Immediate death may occur from
  • 1) Current-induced ventricular fibrillation
  • 2) Asystole
  • 3) Respiratory arrest secondary to
  • Paralysis of the central respiratory control
    system
  • Paralysis of the respiratory muscles

19
History Overview
  • Lightning was attributed to supernatural powers
  • Zeus ruler of the ancient Greek gods holding
    thunderbolts which he used as warning or
    punishment against who disobeyed him

20
  • Zeus, the youngest son of Cronus and Rhea, was
    the supreme ruler of Mount Olympus and of the
    Pantheon of gods who resided there
  • Being the supreme ruler he upheld law, justice
    and morals, and this made him the spiritual
    leader of both gods and men
  • Zeus was a celestial god, and originally
    worshiped as a weather god by the Greek tribes

21
  • He has always been associated as being a weather
    god, as his main attribute is the thunderbolt, he
    controlled thunder, lightning and rain
  • Theocritus wrote circa 265 BCE "sometimes Zeus
    is clear, sometimes he rains
  • He is also known to have caused thunderstorms

22
  • Discovery and widespread use of electricity in
    the mid-1800s took away the supernatural aura
  • 1st electrical fatality recorded in France in 1879

23
  • Thomas Alva Edison was both a scientist and an
    inventor
  • Born in 1847
  • When Edison was born, society still thought of
    electricity as a novelty, a fad. By the time he
    died, entire cities were lit by electricity

24
  • In his lifetime, Edison patented 1,093 inventions
  • The most famous of his inventions was an
    incandescent light bulb
  • He believed in hard work, sometimes working
    twenty hours a day. Edison was quoted as saying,
    "Genius is one percent inspiration and 99 percent
    perspiration"

25
  • In tribute to this important American, electric
    lights in the United States were dimmed for one
    minute on October 21, 1931, a few days after his
    death

26
  • Electrical injuries (excluding lightning) are
    responsible for gt 500 deaths/year in the US
  • gt 1/2 of them occur in the workplace.
  • 4th leading cause of work-related traumatic death
  • Electrocutions at home gt 200 deaths/year

27
  • Lightning responsible for 93 deaths/year in US
  • Morbidity 5-10 times higher than that due to
    other forms of electrical injury
  • Iatrogenic electrical injury in the ICU
    defibrillators, pacemakers, electrosurgical
    devices
  • Story of CPR how to treat electrocuted
    electrical linemen who were in VF

28
Principles of Electricity
  • Electricity flow of electrons (negatively
    charged outer particles of an atom) through a
    conductor
  • When the electrons flow away from this object
    through a conductor they create an electric
    current amperes

29
  • Voltage force that causes electrons to flow
    volts
  • Anything that impedes the flow of electrons
    through a conductor creates resistance ohms

30
  • Power lines range from
  • Low lt 600 volts
  • Ultrahigh gt 1 million volts
  • Utility power lines with high voltages in
    sparsely populated areas
  • Through a succession of transformers voltage is
    gradually reduced
  • Most homes in US Canada have a 120/240 V other
    countries (Europe, Asia..) 220 V

31
The Temple of Artemis at Ephesus
  • A beautiful temple in Asia Minor erected in honor
    of the Greek goddess of hunting and wild nature

32
Pathophysiologic effects of Different Intensities
of Electrical Current
33
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34
  • Electrical current exists in 2 forms
  • 1) AC (Alternating Current) when electrons flow
    back and forth through a conductor in a cyclic
    fashion
  • It is used in household and offices and is
    standardized to a frequency of 60 cycles/sec (60
    Hz)

35
  • 2) DC (Direct Current) when electrons flow only
    in one direction
  • Used in certain medical equipment
    defibrillators, pacemakers, electrical scalpels
  • AC is far more efficient and also more dangerous
    than DC ( 3 times) tetanic muscle contractions
    that prolong the contact of victim with source

36
  • Issue of safety over efficiency early days of
    electricity when Thomas Edison (who developed and
    popularized DC was fighting against George
    Westinghouse (who developed AC)
  • AC first death penalty by electrocution

37
  • Lightning is a form of DC
  • 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
  • Lasts for only 1-2 sec

38
  • Voltage gt1,000,000 V
  • Currents of gt200,000 A
  • Transformation of the electrical energy to heat
    generated temperatures as high as 50,000ºF
  • Extremely short duration prevents from melting

39
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40
The Mausoleum at Halicarnassus
  • A fascinating tomb constructed for King
    Maussollos, Persian satrap of Caria

41
Determinants of Electrical Injuries
  • Ohms law
  • Current Voltage/Resistance
  • Exposure of different parts of the body to the
    same voltage ? different current ? different
    degree of damage because resistance varies

42
  • The least resistance is found in nerves, blood,
    mucous membranes and muscles
  • The highest resistance is found in bones, fat and
    tendons
  • Skins resistance ranging between 40,000 and
    100,000 O depending on thickness
  • Moisture of the skin electrocution of a person
    in a bathtub or swimming pool

43
  • Moist mucus membranes significant orofacial
    injury to infants and toddlers
  • Nerves and blood vessels are the best conductors
    path of least resistance for current after it
    enters the body
  • Duration of the contact shock caused by AC will
    produce bigger injury than shock caused by DC of
    the same amperage

44
  • Pathway of the current through the body
  • Vertical pathway parallel to the axis of the body
    is the most dangerous. It involves all the vital
    organs central nervous system, heart,
    respiratory muscles, in pregnant women the uterus
    and fetus
  • Horizontal pathway from hand to hand the heart,
    respiratory muscles and spinal cord
  • Pathway through the lower part of the body local
    damage

45
The Colossus of Rhodes
  • A colossus of Helios the sun-god, erected by the
    Greeks near the harbor of a Mediterranean Island

46
Electrical Injury to Specific Tissues Organs
  • Cardiovascular System
  • Pathophysiology
  • Direct necrosis of the myocardium
  • Cardiac dysrhythmias

47
  • Focal or diffuse
  • Widespread, discrete, patchy contraction band
    necrosis involving the myocardium, nodal tissue,
    conduction pathways and coronary arteries

48
  • A current gt 50-100 mA with hand-to-hand or
    hand-to-foot transmission ? ventricular
    fibrillation
  • High-voltage current (AC or DC) ? ventricular
    asystole
  • Lightning ? cardiac standstill
  • Sinus rhythm may spontaneously return

49
  • Cardiac dysrhythmias reported in survivors of
    electrical injuries pathogenesis is rather
    unclear, multifactorial

50
  • Possible mechanisms
  • 1) Arrythmogenic foci due to myocardial
  • necrosis (esp. SA Node injury)
  • 2) Alterations in the Na - K adenosine
    triphosphatase concentration
  • 3) Changes in the permeability of myocyte
    membranes
  • 4) Anoxic injury (respiratory arrest precedes the
    injury to the heart)

51
  • Large arteries not acutely affected because their
    rapid flow?dissipate heat. Medial necrosis
    aneurysm formation and rupture
  • Smaller vessels acutely affected d.t. coagulation
    necrosis ? compartment syndrome

52
  • Clinical Manifestations
  • Cardiac standstill, ventricular fibrillation
    most serious
  • Sinus tachycardia, nonspecific ST- and T-wave
    changes much better prognosis
  • Conduction defects, various degrees of heart
    blocks, BBB and ?QT interval

53
  • Supraventricular tachycardias and atrial
    fibrillation usually do not cause significant
    hemodynamic compromise
  • On echocardiogram some depression of the right
    left ejection fractions

54
  • Cutaneous Injuries Burns
  • Extensive flash and flame burns
  • Hemodynamic, autonomic, cardiopulmonary, renal,
    metabolic and neuroendocrine responses

55
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56
  • Nervous System
  • Loss of conciousness, confusion impaired recall
  • Peripheral motor sensory nerves ? motor
    sensory deficits
  • Seizures, visual disturbances deafness
  • Hemiplegia, quadriplegia, spinal cord injury
  • Transient paralysis, autonomic instability ?
    hypertension, peripheral vasospasm due to
    lightning from massive release of catecholamines

57
  • Respiratory System
  • Direct injury to the respiratory control center ?
    cessation of respiration or suffocation secondary
    to tetanic contractions of the respiratory
    muscles
  • Acute respiratory dysfunction syndrome secondary
    to ischemia, aggressive fluid resuscitation,
    ventilator-associated pneumonia

58
  • Other Systems
  • Kidneys susceptible to anoxic/ischemic injury
  • Release of myoglobin creatinine phosphokinase ?
    renal tubular damage ? renal failure
  • Fractures
  • Transient autonomic disturbances ? fixed pupils
    may be perceived as severe brain injury or even
    death
  • Temporary sensorineural hearing loss

59
The Lighthouse of Alexandria
  • A lighthouse built by the Ptolemies on the island
    of Pharos off the coast of their capital city

60
Management of Electrical Injuries
  • Overall fluid management should be judicious
    unless SIADH

61
  • Patient Monitoring
  • Most severe cardiac complications present acutely
  • Very unlikely for a patient to develop a serious
    or life-threatening dysrhythmia hours or days
    later
  • Asymptomatic normal ECG do not need cardiac
    monitoring

62
  • Preexisting heart disease monitor such patients
    for 24 hrs after the injury
  • Criteria for cardiac monitoring
  • Exposure to high voltage
  • Loss of consciousness
  • Abnormal ECG at admission

63
  • Type of cardiac monitoring (controversial)
  • Continuous telemetry
  • Serial ECGs
  • Serial measurement of cardiac enzymes
  • Prognostic value of CK-MB, noninvasive and
    invasive imaging studies (echocardiography,
    thallium studies angiography) rather poor and
    inconsistent
  • Muscles injured by an electrical current can
    contain up to 25 CK-MB fraction (as opposed to
    the normal 2-3)
  • No information regarding changes in troponin

64
Prophylaxis...
  • One ounce of prevention is worth a pound of
    treatment

65
The Great Pyramid of Giza
  • A gigantic stone structure near the ancient city
    of Memphis, serving as a tomb for the Egyptian
    Pharaoh Khufu
  • Man fears Time, yet Time fears the Pyramids
  • Arab proverb

66

"Genius is one percent inspiration and 99 percent
perspiration."
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