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 77% 0-5 YO 60% extremity 40% oral commisure No mortality Complete functional recovery High Voltage 76% 11-18 YO 33% limb amputations 30% deep muscles 12% fasciotomy/ escharotomy 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 ACLS ו- ATLS החייאת נוזלים אקספלורציה והטרייה מוקדמים טיפול דפיניטיבי מוקדם – בכל שיטות השחזור המקובלות