This document discusses electrical injuries, including the pathophysiology, mechanisms of injury, and treatment approaches. It notes that electrical injuries can cause severe burns, cardiac arrest, respiratory failure, muscle damage, and compartment syndrome. The severity depends on factors like voltage, current, resistance, and pathway of the electrical current. Treatment involves stabilizing the patient, monitoring for arrhythmias, treating burns, preventing compartment syndrome and renal failure, and managing pain. Wound care aims to remove dead tissue while preventing infection.

1. Introduction to
Electrical Injury
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2. • Electrical burns: a small part of major burn
centers  5-7%
• Most devastating of thermal injuries on size-
to-size basis: involving both skin and deeper
tissue
• Most frequent cause of amputation in burn
service

3. PATHOPHYSIOLOGY

4. • Exact pathophysiology is unknown
• Numerous variables cannot be measured
when an electrical currents pass through the
tissue
• With high voltage (≥1000V), most of injury is
thermal and resulting in coagulation necrosis
• The injury can be explained by Ohm’s Law

5. I = V/R
P = I2R
I = current, in amperes (A)
V = potential, in volts (V)
R = resistance, in ohms (Ω)
P = power, in Joules (J)

6. Factors Determining Severity
• Type of circuit
• Duration
• Resistance of tissue
• Voltage
• Amperage
• Pathway of current

7. Type of Circuit
• Direct (DC) or alternating current (AC)
• DC: Cause single spasm and throw the victim
from the source  increased traumatic blunt
injury
• AC: cause continuous muscle contraction or
tetany  no-let-go phenomenon and creating
potential for continually increasing severity
– Occur when both flexor and extensor are stimulated
but flexor is stronger making victim unable to let go
voluntarily

8. Duration of Contact
• Longer duration with high-voltage current 
greater tissue destruction

9. Tissue Resistance
• The word entrance and exit  replaced by
contact points
• The higher resistance, the greater
transformation electrical injury to thermal
injury
• Least: nerve, blood, mucous membrane,
muscle
• Intermediate: dry skin
• Most: tendon, fat, bone

10. Tissue Resistance: skin
• Primary resistor
• Thick and harden skin = greater resistance
• Sweating: decrease resistance

11. Voltage
• Low voltage < 1000V
• High voltage ≥ 1000V
• Thailand domestic wiring 220V
• Higher voltage, higher morbidity

12. Amperage
• P = I2R and I = V/R
• More amperage, more heat
• The voltage of source is often known but not
for resistance
• Physical effects vary with different amperage

13. Price TG and Cooper MA. Electrical and lightning injuries: in Rosen’s emergency
medicine. Access via PDF

14. Pathway
• Where the current passes: between the
contact points

15. MECHANISMS OF INJURY

16. • Primary is burn
• Secondary: fall or being thrown from electrical
source by muscle contractioin
• 4 types of electrical burn
– Direct contact: electrothermal heating
– indirect contact: arc, flame

17. • Electrical arc:
– A current spark between 2 objects differing
potential not contact to each other
– Most destructive indirect injury
– Usually highly charged source and a ground
– Temperature of the arc reaches 2500oC
• Flame: result from ignition of clothing

18. Heart
• Most serious: cardiac arrest
• Dysrhythmia: AF
• ECG abnormality: non-specific ST-T change
• Can occur both low and high voltage
• ECG monitoring is mandatory in patients with
ECG abnormality

19. Respiratory
• May result from:
– Tetanic contraction of thoracic musculature
– Injury to respiratory control center of CNS
– Combined cardiopulmonary arrest secondary to
asystole or VF
– Blunt chest trauma from being thrown

20. Cutaneous
• Low voltage: small, well-demarcated contact
burns
• High voltage: painless, depressed, yellow-gray,
charred craters with central necrosis, or may
spare the skin surface but damage deeper
tissue

21. Czuczman AD. Electrical injuries: a review for the emergency physician. 2009;11(10):1-21

22. Muscle
• Coagulation necrosis  becoming edematous
and necrotic 
• Myoglobinuria, rhabdomyolysis, and acute
renal failure
• Compartment syndrome

23. Myoglobinuria
• Dark urine, mahogany-colored
• Significant muscle damage with potentially
ischemia
• UA: urine dipstick +ve for blood with few RBC
• Risk of acute renal failure
• Elevated CPK

24. Compartment Syndrome
• High-voltage injury: risk for developing
compartment syndrome in first 48 hours
• Damaged and swelling muscle  increased
pressure within fascia
• CK level: associated with extent of muscle
damage

25. Vascular
• Greatest damage to media layer  delayed
aneurysm formation
• Intima: thrombosis and occlusion
• Most severe in small muscle branch: tissue
necrosis
• Any vascular injury can cause compartment
syndrome

26. Neurologic
• PNS > CNS in electrical injuries
• Most common CNS symptom = loss conscious
• Others: peripheral neuropathy, transient
paralysis, spinal cord damage

27. Gastrointestinal injuries
• Suspected in burn at abdominal wall
• History of fall, blast, blunt trauma

28. Oral Burn
• Children who put a power cord in the mouth
• Labial artery bleeding: occur up to 2 weeks
after injury

29. • Eye injury: cataracts
• Auditory system: path of current may be
damaged

30. Czuczman AD. Electrical injuries: a review for the emergency physician. 2009;11(10):1-21.

31. TREATMENT

32. Prehospital Care
• Secure the scene
• Ensure that the power source has been turned
off
• CPR + follow ACLS
• Protect cervical spine and splint fracture
• Close burn wound with clean dry dressing

33. ER care
• Follow ACLS and ATLS
• Resuscitation
• Complete lab
• Remove constricting objects
• ECG

34. Fluid Resuscitation
• Parkland formula: only rough starting point
• In absence of gross myo/hemoglobinuria, goal
is to maintain v/s: 0.5 ml/kg/hr
• In children:
– 10% burn: resuscitation
– Fluid of choice: LRS
– <2years: 5%DLR
– Maintenance fluid: 5%DN/2

35. ECG monitoring
Czuczman AD. Electrical injuries: a review for the emergency physician. 2009;11(10):1-21.

36. ECG monitoring
• Duration: 24-48 hours
• Low voltage + normal ECG: can be discharged
• Utility of CK-MB:
– Not reliable due to other muscle injury
– Use of troponin: insufficient data

37. Treatment of Myoglobinuria
• Monitoring urine for myoglobin and serum for
CPK
• Maintain a urine output “double” goal rate: 1
– 1.5 ml/kg/hr
• Fluid should be NSS 1000 ml + NaHCO3 50
mEq
• pH of ABG: > 7.45
• Mannitol: 25 g, then 12.5 g/h

38. Compartment Syndrome
• 4 compartment fasciotomies for lower
extremities
• Anterior and posterior fasciotomies with
carpal tunnel release for upper extremities
• Primary amputations are not generally
performed

40. Wound Care
• Dressing wound with sulfamylon on the thick
eschar
• SSD: for microbial control
• Biologic dressing on more superficial area
• Remove necrotic tissue and reevaluate q2-
3days
• Tetanus immunization

41. Pain Management
• Acute pain: opioids and paracetamol
• Rehabilitation phase: NSAIDs, antidepressant,
massage therapy, cognitive behavioral therapy

42. References
ชัยรัตน์ บุรุษพัฒน์. Electrical injuries: principle and management. เวชสารแพทย์
ทหารบก.2011;4:207-10.
Herndon DN. Total burn care. 4th ed. China: Elsevier, 2012.
Arnoldo B, Klein M, Gibran NS. Practice guidelines for the management of
electrical injuries. Journal of burn care and research. 2006;27(4):439-46.
Czuczman AD. Electrical injuries: a review for the emergency physician.
2009;11(10):1-21.
Fish RM. Electric injury, part II: specific injuries. The journal of emergency
medicine. 2000;18(1):27-34.

43. References
Price TG and Cooper MA. Electrical and lightning injuries: in Rosen’s
emergency medicine. Access via PDF
Guidelines for paediatric burn resuscitation