Electrical Injury

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Electrical Injury
Electrical Injury
• In the U.S. 52,000 admissions/yr
• 3-8 % of all burn unit
admissions
• May-Sept lightning related.
• Decrease in incidence due to
GFCIs
Electrical Injury - Epidemiology
• Ages 15-44 yrs.
• High voltage mostly occupational injury
• 20% Children
– Low voltage injuries in toddlers
M:F 1.7:1
– High voltage injuries in adolescents
97% male
Electrical Injury Pathophysiology
• Electrical – tetany, arrhythmia
• Thermal – burns, coagulation
• Mechanical – fractures, dislocation
Ohm’s Law
I= V/R
I= current
V= voltage
R= resistence
Joule’s Law
E=I²RT
E= energy
I= current
R= Resistence
T= time
Electrical Injury Pathophysiology
Current pathway defines resistence
- Vertical higher incidence of complication
- Hand – to – hand pathway
- Below symphysis, stradle pathway
Electrical Injury - Classification
• High (>1000 Volt) vs. low (<1000 Volt)
voltage
• Direct (lightning) vs. alternating (50 Hz)
current
• Arc injury (high temperature), flashover
Cardiovascular Involvment
• Mostly in vertical injury
• DC – Asystole
• AC
– High VF/ VT, asystole
– Low  ectopic beats, AF, tachycardia,
bradycardia, ECG changes
• Coagulation necrosis, coronary spasm, MI
Respiratory Involvement
• Tetany of respiratory
muscle
• Brain stem injury
• May induce hypoxia,
acidosis  cardiac arrest
Nervous System
• Immediate - loss of
consciousness, amnesia
• Early - intracranial
hemorrhage, vertebral
fractures
• Late - ALS, transverse
myelitis, ascending paralysis
• Peripheral neuropathy, RSD
Vascular Injury
• Large arteries – medial necrosis, aneurisms
• Small vessels – intimal injury, coagulation
necrosis
• Secondary to compartment syndrome
Limb Injury
• Dislocations and fractures
• Coagulation of blood vessels
• Muscle ischemia and edema
• Compartment syndrome
• Thermal injury from bone heating
• Infection clostridial, streptococcal
Other Injuries
• GI – ileus, stress ulcers, direct injury
• Ophthalmic – cataract, iridiocyclitis,
autonomic injury
• Otologic – tympanic membrane
perforation, vertigo, sensoryneural injury
Injury Characteristics
Low Voltage
High Voltage
• 77% 0-5 YO
• 76% 11-18 YO
• 60% extremity
• 33% limb amputations
• 40% oral commisure
• 30% deep muscles
• No mortality
• 12% fasciotomy/
escharotomy
• Complete functional
recovery
• No mortality
Electrical Injury Management
• Combined ATLS + ACLS protocols
• Cardiac monitoring for 24 hrs if LOC,
ECG changes or arrhythmias
• IM dT
• IV H2 - blockers
Electrical Injury – Resuscitation
• 1.7 X Parkland formula or 9 ml/kg/%TBSA
• Urine output 70 - 100 ml/hour
• Clearance of any pigment in urine
• Bicarbonate - blood pH > 7.45
• Osmotic diuresis – IV MANNITOL 25 gr
Electrical Injury –
Wound Managemant
“True” high tension
• Sharply demarcated
• Always full thickness
• Leathery appearence
Electrical injury –
Wound Management
•“Progressive necrosis” theory
• Primary resuscitation.
• Early exploration and debridment
• “Second look” in 24-48 hrs –definitive Tx
– Primary closure
– Coverage
– Amputation
Wound Management –
Extremities
• Frequent envolvement of the hand
• Exit point in one or both legs
• Arc injury in distal fore arm or axilla
Wound Management –
Extremities
• Initial assessment usually predicts
outcome:
– Depth of burns
– Ischemia
– Anasthesia
– Flexion position
– Muscle viability- response to
electrocautery
Electrical Burn - Extremities
Wound Management –
Extremities
• Exploration - large volume underlying
necrotic area
• Full thickness burns
• Proximal periosseous myonecrosis
• Retained questionable tissue may lead to
contamination and further compromise
Wound Management - Scalp
• Saucer shaped, deapest in the middle
• Delayed Tx  osteomyelitis and epidural
abscess
• Debridment of soft tissue, outer cortical
bone and skin grafting
• Full thicknss skull - devitalization & flap
coverage
Wound Management –
Trunk & perineum
• Suspect visceral injury
• Lung – Atelectasis and edema
• Abdomen – consider as penetrating wound
• Perineum –urinary and bowel diversion &
debridment +STSG
‫‪Electrical Injury -Summery‬‬
‫• סוג הפגיעה ומיקומה‬
‫• טיפול ראשוני לפי פרוטוקולים ‪ ACLS‬ו‪ATLS -‬‬
‫• החייאת נוזלים‬
‫• אקספלורציה והטרייה מוקדמים‬
‫• טיפול דפיניטיבי מוקדם – בכל שיטות השחזור‬
‫המקובלות‬
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