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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 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)
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
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
• Prior to arrival to the hospital:
• SVT --> Cardioversion x 5
• Hypotension --> Dopamine and Epinephrine drips
• Intubated
• Vitals on arrival:– Pulse: 101– BP: 71/46– RR: 24
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
• 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
Trop 1.38 2.87 1.81
CK 9892190
CKMB 19.417.2
CKMB index 2.0 0.8
Myoglobin > 500 > 500
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
TTE on admission
• Mild eccentric LVH
• LV systolic function was moderately to severely decreased
• EF: 25-30%
Day 3:
• Levophed discontinued
• Weaned off of the vent & extubated
• Blood culture: MRSA
Day 8:
• Discharged home on: pain meds & antibiotics
TTE (prior to d/c)
• Normal left ventricular systolic function
• EF: 65%
The Hanging Gardens of Babylon
• A palace with legendary gardens built on the banks of the Euphrates river by King Nebuchadnezzar II
ELECTRICAL INJURIESCritical Care Medicine
Volume 30.Number 11.November 2002
• Adults in workplace, children at home
• Severity of injury depends on:– Intensity of electrical current (voltage of
source and resistance of victim)– Pathway through victim’s body– Duration of the contact with the source
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
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
• 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
• 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
• Discovery and widespread use of electricity in the mid-1800s took away the supernatural aura
• 1st electrical fatality recorded in France in 1879
• 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
• 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"
• 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
• Electrical injuries (excluding lightning) are responsible for > 500 deaths/year in the US
• > 1/2 of them occur in the workplace.
• 4th leading cause of work-related traumatic death
• Electrocutions at home: > 200 deaths/year
• 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
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
• Voltage: force that causes electrons to flow: volts
• Anything that impedes the flow of electrons through a conductor creates resistance: ohms
• Power lines range from:– Low: < 600 volts
– Ultrahigh: > 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
The Temple of Artemis at Ephesus
• A beautiful temple in Asia Minor erected in honor of the Greek goddess of hunting and wild nature
Pathophysiologic effects of Different Intensities of
Electrical Current
• 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)
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
• 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
• 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
• Voltage >1,000,000 V
• Currents of >200,000 A
• Transformation of the electrical energy to heat generated temperatures as high as 50,000ºF
• Extremely short duration prevents from melting
The Mausoleum at Halicarnassus
• A fascinating tomb constructed for King Maussollos, Persian satrap of Caria
Determinants of Electrical Injuries
• Ohm’s law:
Current = Voltage/Resistance
• Exposure of different parts of the body to the same voltage different current different degree of damage because resistance varies
• The least resistance is found in nerves, blood, mucous membranes and muscles
• The highest resistance is found in bones, fat and tendons
• Skin’s resistance ranging between 40,000 and 100,000 Ω depending on thickness
• Moisture of the skin; electrocution of a person in a bathtub or swimming pool
• 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
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
The Colossus of Rhodes
• A colossus of Helios the sun-god, erected by the Greeks near the harbor of a Mediterranean Island
Electrical Injury to Specific Tissues & Organs
Cardiovascular System:
Pathophysiology:
• Direct necrosis of the myocardium
• Cardiac dysrhythmias
• Focal or diffuse
• Widespread, discrete, patchy contraction band necrosis involving the myocardium, nodal tissue, conduction pathways and coronary arteries
• A current > 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
• Cardiac dysrhythmias reported in survivors of electrical injuries pathogenesis is rather unclear, multifactorial
• 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)
• 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
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
• Supraventricular tachycardias and atrial fibrillation: usually do not cause significant hemodynamic compromise
• On echocardiogram: some depression of the right & left ejection fractions
Cutaneous Injuries & Burns
• Extensive flash and flame burns
• Hemodynamic, autonomic, cardiopulmonary, renal, metabolic and neuroendocrine responses
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
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
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
The Lighthouse of Alexandria
• A lighthouse built by the Ptolemies on the island of Pharos off the coast of their capital city
Management of Electrical Injuries
Overall fluid management should be judicious unless: SIADH
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
• 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
• 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
Prophylaxis...
“One ounce of prevention is worth a pound of treatment”
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
"Genius is one percent inspiration and 99 percent perspiration."