Electrical injuries: Difference between revisions
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==Background== | ==Background== | ||
*Tissue damage occurs via electrical energy (becomes thermal energy once it enters the body) and mechanical injury from trauma | *Tissue damage occurs via electrical energy (becomes thermal energy once it enters the body) and mechanical injury from trauma | ||
** | **Fat, bone, tendon, dry skin all have very high resistance | ||
**Muscle, nerves, vasculature have lower resistance, more often damaged | **Muscle, nerves, vasculature have lower resistance, more often damaged | ||
*'''The primary determinant of injury is the amount of current flowing through the body, which depends on:''' | *'''The primary determinant of injury is the amount of current flowing through the body, which depends on:''' | ||
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#'''Electric Arc''' | #'''Electric Arc''' | ||
#*Associated with high voltage sources | #*Associated with high voltage sources | ||
#*Ionized particles with temperature 3000 °C–20,000 | #*Ionized particles with temperature 3000 °C–20,000 °C<ref name="Epidemiology">Kym D, Seo DK, Hur GY, Lee JW. Epidemiology of electrical injury: Differences between low- and high-voltage electrical injuries during a 7-year study period in South Korea. Scand J Surg. 2015 Jun;104(2):108-14.</ref> | ||
#*Can jump 2-3cm per 1000V<ref name="Epidemiology" /> | #*Can jump 2-3cm per 1000V<ref name="Epidemiology" /> | ||
#*May radiate enough heat to burn persons 10ft or more away from the arc | #*May radiate enough heat to burn persons 10ft or more away from the arc | ||
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====DC==== | ====DC==== | ||
*Direct current most often demonstrates flow-over phenomenon | *Direct current most often demonstrates flow-over phenomenon | ||
* | *Lightning can reach 1-5 million volts, but current flows over the body and exits to the ground | ||
*May result in little tissue damage | *May result in little tissue damage but [[cardiac dysrrhythmias]] are still of great concern | ||
====AC==== | ====AC==== | ||
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==Clinical Features== | ==Clinical Features== | ||
[[File:PMC5253516 icrp a 1275646 f0001 c.png|thumb|Superficial second degree burn from [[lightning injury]].]] | |||
[[File:PMC4763624 IJD-61-109-g002.png|thumb|Lichtenberg figure from [[lightning injury]].]] | |||
[[File:PMC4891493 CCR3-4-618-g001.png|thumb|Patterned charring along the contact points of a metallic locket due to [[lightning strike]].]] | |||
[[File:Verbrennung Grad 2b.jpg|thumb|Second-degree burn after a high tension line electrical injury.]] | |||
===Immediate Effects=== | ===Immediate Effects=== | ||
*[[Cardiac dysrhythmias]] | *[[Cardiac dysrhythmias]] | ||
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===[[Cardiac Dysrhythmias]]=== | ===[[Cardiac Dysrhythmias]]=== | ||
*Fatalities due to [[asystole]] or [[V-fib]] usually occur prior to arrival | *Fatalities due to [[asystole]] or [[V-fib]] usually occur prior to arrival | ||
**Most common [[ | **Most common [[dysrhythmia]] at presentation is [[A-fib]] ([[V-fi]]b is more common, but patients are dead PTA) | ||
**Asymptomatic patients with normal [[ECGs]] do not develop later dysrhythmias after <1000V injuries | **Asymptomatic patients with normal [[ECGs]] do not develop later dysrhythmias after <1000V injuries | ||
***For uncomplicated electrical injuries if normal EKG then routine ECG monitoring and cardiac biomarkers unnecessary<ref>Pilecky D, Vamos M, Bogyi P, et al. Risk of cardiac arrhythmias after electrical accident: a single-center study of 480 patients. Clin Res Cardiol. 2019;108(8):901–908. doi:10.1007/s00392-019-01420-2 Abstract at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6652167/</ref>. | |||
===Cardiovascular Injury=== | ===Cardiovascular Injury=== | ||
*Contraction band necrosis<ref>Koumbourlis AC. Electrical injuries. Crit Care Med. 2002 Nov;30(11 Suppl):S424-30.</ref> | *Contraction band necrosis<ref>Koumbourlis AC. Electrical injuries. Crit Care Med. 2002 Nov;30(11 Suppl):S424-30.</ref> | ||
*Medial necrosis of large vessels | *Medial necrosis of large vessels | ||
**Aneurysm formation | **[[LV aneurysm|Aneurysm]] formation | ||
*Coagulation necrosis of small vessels | *Coagulation necrosis of small vessels | ||
**Can lead to [[compartment syndrome]] | **Can lead to [[compartment syndrome]] | ||
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===CNS Injury=== | ===CNS Injury=== | ||
*Occurs in 50% of patients with high-voltage injuries | *Occurs in 50% of patients with high-voltage injuries | ||
*Brain injury ranges from transient LOC to [[CVA]] to [[respiratory arrest]] | *Brain injury ranges from transient [[syncope|LOC]] to [[CVA]] to [[respiratory arrest]] | ||
*High voltage injuries involving head are frequently associated with coma and persistent vegetative state | *High voltage injuries involving head are frequently associated with [[coma]] and [[Persistent Vegetative State|persistent vegetative state]] | ||
===Orthopedic Injury=== | ===Orthopedic Injury=== | ||
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**Need for [[fasciotomy]] predicted by: | **Need for [[fasciotomy]] predicted by: | ||
***Myoglobinuria | ***Myoglobinuria | ||
***Burns >20% BSA | ***Burns >20% [[BSA]] | ||
***Full-thickness [[burn]] >12% BSA | ***Full-thickness [[burn]] >12% [[BSA]] | ||
*[[Rhabdomyolysis]] | *[[Rhabdomyolysis]] | ||
**Associated with: | **Associated with: | ||
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**Document presence or absence of cataracts following all electrical injuries | **Document presence or absence of cataracts following all electrical injuries | ||
===Auditory Injury=== | ===[[hearing loss|Auditory Injury]]=== | ||
*May be damaged by current or hemorrhage | *May be damaged by current or hemorrhage | ||
*Check hearing in all patients | *Check hearing in all patients | ||
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**Seriously injured patients often have burns on either arm or skull + feet | **Seriously injured patients often have burns on either arm or skull + feet | ||
*Most patients with burns from electrical injury require admission and care by burn specialist | *Most patients with burns from electrical injury require admission and care by burn specialist | ||
*Lichtenberg figures (not true burns) are pathognomonic for lightning strike | |||
===GI Injury=== | ===GI Injury=== | ||
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===Pediatric Considerations=== | ===Pediatric Considerations=== | ||
*In general, evaluate as for the adult, looking for multi-system involvement | *In general, evaluate as for the adult, looking for multi-system involvement | ||
*Perform an ECG in all patients, regardless of voltage | *Perform an [[ECG]] in all patients, regardless of voltage | ||
*An oral commissure burn (from chewing on power cord) will create significant edema and necrosis | *An oral commissure burn (from chewing on power cord) will create significant edema and necrosis | ||
**The child may need Plastic Surgery or Head and Neck Surgery consultation to avoid microstomia | **The child may need Plastic Surgery or Head and Neck Surgery consultation to avoid microstomia | ||
**1-2 weeks after the burn, the eschar may fall off, exposing the labial artery and causing significant hemorrhage | **1-2 weeks after the burn, the eschar may fall off, exposing the labial artery and causing significant hemorrhage | ||
***Provide clear and thorough precautionary advice including first aid for bleeding (pinch buccal mucosa against outside of cheek until arrival to hospital) | ***Provide clear and thorough precautionary advice including first aid for bleeding (pinch buccal mucosa against outside of cheek until arrival to hospital) | ||
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==Evaluation== | ==Evaluation== | ||
===Workup=== | ===Workup=== | ||
*12-lead ECG | *12-lead [[ECG]] | ||
*CBC | *CBC | ||
*CMP | *CMP | ||
*Lactate | *[[Lactate]] | ||
*Troponin | *[[Troponin]] | ||
*CK | *CK | ||
*[[Urinalysis]] and urine | *[[Urinalysis]] | ||
**Urine myoglobin is poorly sensitive/specific, and most patients with rhabdomyolis will have grossly discolored urine<ref>https://emergencymedicinecases.com/electrical-injuries/</ref> | |||
===Diagnosis=== | ===Diagnosis=== | ||
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*Usual trauma evaluation and resuscitation applies | *Usual trauma evaluation and resuscitation applies | ||
*Use [[Parkland formula]] as starting point for [[fluid resuscitation]] | *Use [[Parkland formula]] as starting point for [[fluid resuscitation]] | ||
**Fluids in first 24 hrs = | **Fluids in first 24 hrs = [[T[[BSA]]]] burned(%) x Wt(kg) x 4ml; Give 1/2 in first 8 hours, then give other 1/2 over next 16 hrs | ||
**Parkland formula frequently underestimates fluid requirements in electrical burns<ref>https://emergencymedicinecases.com/electrical-injuries/</ref> | |||
**In healthy individuals start continuous fluids at 300-500 mL/hr and titrate to urine output of 100 mL/hr<ref>https://emergencymedicinecases.com/electrical-injuries/</ref> | |||
*Treat [[rhabdomyolysis]] and [[compartment syndrome]] in usual manner | *Treat [[rhabdomyolysis]] and [[compartment syndrome]] in usual manner | ||
**If RBCs and/or myoglobin in UA, urine should be alkalinized at minimum of 2 cc/kg/hr until pigments eliminated<ref>Brandt CP, Yowler CJ, Fratianne RB. MetroHealth Medical Center Burn ICU Handbook (Not a policy manual), Cleveland, OH.</ref> | **If RBCs and/or myoglobin in UA, urine should be alkalinized at minimum of 2 cc/kg/hr until pigments eliminated<ref>Brandt CP, Yowler CJ, Fratianne RB. MetroHealth Medical Center Burn ICU Handbook (Not a policy manual), Cleveland, OH.</ref> | ||
**[[Mannitol]] should be given early to prevent renal tubular damage | **[[Mannitol]] should be given early to prevent renal tubular damage but patient must remain adequately fluid resuscitated | ||
**High voltage injuries to the hand frequently require carpal tunnel decompression as soon as patient is stable for OR | **High voltage injuries to the hand frequently require carpal tunnel decompression as soon as patient is stable for OR | ||
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*Abnormal [[ECG]] or observed dysrhythmia | *Abnormal [[ECG]] or observed dysrhythmia | ||
*Cardiac biomarkers positive | *Cardiac biomarkers positive | ||
*Persistent [[chest pain]], paresthesias, or [[hypoxia]] | *Persistent [[chest pain]], [[paresthesias]], or [[hypoxia]] | ||
*[[Cardiac arrest]] | *[[Cardiac arrest]] | ||
*History of significant cardiac disease or CAD risk factors | *History of significant cardiac disease or CAD risk factors | ||
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==External Links== | ==External Links== | ||
*[http://pemplaybook.org/podcast/electrical-injuries-hertz-so-bad/ Electrical Injuries: Hertz So Bad - Pediatric Emergency Playbook] | *[http://pemplaybook.org/podcast/electrical-injuries-hertz-so-bad/ Electrical Injuries: Hertz So Bad - Pediatric Emergency Playbook] | ||
*[https://emergencymedicinecases.com/electrical-injuries/ Emergency Medicine Cases - Electrical Injuries] | |||
==References== | ==References== |
Revision as of 19:09, 3 February 2020
Background
- Tissue damage occurs via electrical energy (becomes thermal energy once it enters the body) and mechanical injury from trauma
- Fat, bone, tendon, dry skin all have very high resistance
- Muscle, nerves, vasculature have lower resistance, more often damaged
- The primary determinant of injury is the amount of current flowing through the body, which depends on:
- Voltage
- Amperage
- Resistance
- Type of current (DC or AC)
- Current pathway
- Duration of contact
Electrical Injury Types
- Low-Voltage <1000V
- High-Voltage >1000V - typically seen in industrial settings or transmission line injuries
- Associated with electrical burns
- Lightning Strike
- Electric Arc
DC vs AC
Direct current (DC) injuries typically due to lightning while alternating current (AC) are household injuries
DC
- Direct current most often demonstrates flow-over phenomenon
- Lightning can reach 1-5 million volts, but current flows over the body and exits to the ground
- May result in little tissue damage but cardiac dysrrhythmias are still of great concern
AC
- Current arcs onto body, envelops surface of body, then arcs to lower electromotive potential (ground)
- With alternative cycle of the current there is contraction and release of muscle preventing full release from source
- Current flows through body tissues
Clinical Features
Immediate Effects
Cardiac Dysrhythmias
- Fatalities due to asystole or V-fib usually occur prior to arrival
- Most common dysrhythmia at presentation is A-fib (V-fib is more common, but patients are dead PTA)
- Asymptomatic patients with normal ECGs do not develop later dysrhythmias after <1000V injuries
- For uncomplicated electrical injuries if normal EKG then routine ECG monitoring and cardiac biomarkers unnecessary[2].
Cardiovascular Injury
- Contraction band necrosis[3]
- Medial necrosis of large vessels
- Aneurysm formation
- Coagulation necrosis of small vessels
- Can lead to compartment syndrome
CNS Injury
- Occurs in 50% of patients with high-voltage injuries
- Brain injury ranges from transient LOC to CVA to respiratory arrest
- High voltage injuries involving head are frequently associated with coma and persistent vegetative state
Orthopedic Injury
- Forceful muscle contractions can cause fracture and joint dislocations (especially shoulder)
- May occur with voltages as low as 120V
- Compartment Syndrome
- Usually associated with high-voltage injuries
- May occur even with 120V shocks if contact is sustained for longer than few seconds
- Patient experiences ongoing muscle pain with movement
- Need for fasciotomy predicted by:
- Rhabdomyolysis
- Associated with:
- Contact with >1000V
- Prehospital cardiac arrest
- Crush injury
- Compartment syndrome
- Full-thickness skin burns
- Associated with:
Ocular Injury
- Cataract formation has been described weeks to years after electrical injury
- Document presence or absence of cataracts following all electrical injuries
Auditory Injury
- May be damaged by current or hemorrhage
- Check hearing in all patients
Cutaneous Burns
- Often seen at electrical contact areas
- Seriously injured patients often have burns on either arm or skull + feet
- Most patients with burns from electrical injury require admission and care by burn specialist
- Lichtenberg figures (not true burns) are pathognomonic for lightning strike
GI Injury
- Suspect in patients with:
- Electrical burns of abdominal wall
- History of a fall, nearby explosion, or other mechanical trauma
Pediatric Considerations
- In general, evaluate as for the adult, looking for multi-system involvement
- Perform an ECG in all patients, regardless of voltage
- An oral commissure burn (from chewing on power cord) will create significant edema and necrosis
- The child may need Plastic Surgery or Head and Neck Surgery consultation to avoid microstomia
- 1-2 weeks after the burn, the eschar may fall off, exposing the labial artery and causing significant hemorrhage
- Provide clear and thorough precautionary advice including first aid for bleeding (pinch buccal mucosa against outside of cheek until arrival to hospital)
Differential Diagnosis
Burns
- Smoke inhalation injury (airway compromise)
- Chemical injury
- Acrolein
- Hydrochloric acid
- Tuolene diisocyanate
- Nitrogen dioxide
- Systemic chemical injury
- Specific types of burns
- Associated toxicities
Evaluation
Workup
- 12-lead ECG
- CBC
- CMP
- Lactate
- Troponin
- CK
- Urinalysis
- Urine myoglobin is poorly sensitive/specific, and most patients with rhabdomyolis will have grossly discolored urine[4]
Diagnosis
- Typically a clinical diagnosis
Management
- Usual trauma evaluation and resuscitation applies
- Use Parkland formula as starting point for fluid resuscitation
- Fluids in first 24 hrs = [[TBSA]] burned(%) x Wt(kg) x 4ml; Give 1/2 in first 8 hours, then give other 1/2 over next 16 hrs
- Parkland formula frequently underestimates fluid requirements in electrical burns[5]
- In healthy individuals start continuous fluids at 300-500 mL/hr and titrate to urine output of 100 mL/hr[6]
- Treat rhabdomyolysis and compartment syndrome in usual manner
- If RBCs and/or myoglobin in UA, urine should be alkalinized at minimum of 2 cc/kg/hr until pigments eliminated[7]
- Mannitol should be given early to prevent renal tubular damage but patient must remain adequately fluid resuscitated
- High voltage injuries to the hand frequently require carpal tunnel decompression as soon as patient is stable for OR
Disposition
Discharge
- Asymptomatic patients with normal ECG on presentation after a low-voltage electrical injury[8]
Admit
- All patients with high-voltage injuries (even if asymptomatic)
- Patients with low-voltage injury if symptomatic (e.g. LOC, severe burns, ECG changes, ↑ CK)
- Abnormal ECG or observed dysrhythmia
- Cardiac biomarkers positive
- Persistent chest pain, paresthesias, or hypoxia
- Cardiac arrest
- History of significant cardiac disease or CAD risk factors
See Also
External Links
- Electrical Injuries: Hertz So Bad - Pediatric Emergency Playbook
- Emergency Medicine Cases - Electrical Injuries
References
- ↑ 1.0 1.1 Kym D, Seo DK, Hur GY, Lee JW. Epidemiology of electrical injury: Differences between low- and high-voltage electrical injuries during a 7-year study period in South Korea. Scand J Surg. 2015 Jun;104(2):108-14.
- ↑ Pilecky D, Vamos M, Bogyi P, et al. Risk of cardiac arrhythmias after electrical accident: a single-center study of 480 patients. Clin Res Cardiol. 2019;108(8):901–908. doi:10.1007/s00392-019-01420-2 Abstract at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6652167/
- ↑ Koumbourlis AC. Electrical injuries. Crit Care Med. 2002 Nov;30(11 Suppl):S424-30.
- ↑ https://emergencymedicinecases.com/electrical-injuries/
- ↑ https://emergencymedicinecases.com/electrical-injuries/
- ↑ https://emergencymedicinecases.com/electrical-injuries/
- ↑ Brandt CP, Yowler CJ, Fratianne RB. MetroHealth Medical Center Burn ICU Handbook (Not a policy manual), Cleveland, OH.
- ↑ Rai J, Jeschke MG, Barrow RE, Herndon DN. Electrical Injuries: A 30-Year Review. J Trauma Acute Care Surg. 1999;46(5):933-936.