aka Trauma Tribulation 029
A 35 year-old man is brought in by ambulance following a motor vehicle crash. He was the passenger in a car that tipped over onto the passenger’s side. Unfortunately, your patient had his left arm hanging outside of the front passenger window and it was trapped under the vehicle. His arm was released by bystanders when they pushed the car back onto its wheels. The paramedics are understandably concerned about the man’s arm.
The trauma team get to work straight away, feeling secure in the knowledge that you, the team leader, are an ‘extremity injury guru’…
Q1. What extremity injuries are potentially life-threatening?
- Pelvic disruption with massive hemorrhage
- Severe arterial hemorrhage
- Crush syndrome
Q2. What extremity injuries are potentially limb-threatening?
- Open fractures/ dislocations
- Traumatic amputation and severe vascular injuries
- Compartment syndrome
- Neurological compromise due to limb injury
- Degloving injuries
Q3. How would you recognize and manage crush syndrome from extremity trauma?
Crush syndrome is the complex of electrolyte disturbances, metabolic acidosis and rhabdomyolysis resulting from crush injury.
- Suspect based on history of crush injury or entrapment
- Hyperkalemia, hypocalcemia, hyperphosphatemia, and hyperuricemia from cellular damage
- Lactic acidosis from hypoperfusion
- Elevated creatine kinase and myoglobinuria (urinalysis positive for blood on dipstick, but no red cells seen on microscopy) due to massive muscle damage
- Acute renal failure due to rhabdomyolysis
- X-rays to assess for associated fractures
- Assess for compartment syndrome
- Assess for neurological compromise (weakness, paresthesiae, loss of sensation and neuropathic pain)
- Assess for vascular compromise (hard and soft signs of vascular injury, ankle-brachial index, CT arteriography)
- resuscitation of shocked patients
- IV hydration (e.g. Hartmann’s) to target urine output of 1-2 mL/kg/h (corrects hypoperfusion, lactic acidosis, ameliorates acute renal impairment)
- Urinary alkalinisation with sodium bicarbonate is controversial, and is unproven. Proponents use this treatment based on the theory that urine pH>7.0 may limit crystalinisation of uric acid and reduce breakdown of myoglobin into nephrotoxic metabolites.
- Mannitol is also sometimes used but is unproven.
- Aggressively treat potentially life-threatening hyperkalemia (calcium gluconate, salbutamol, insulin, hemodialysis)
- Calcium administration may lead to metastatic calcification in the presence of hyperphosphatemia
- Treat associated injuries including fractures/ dislocations, wounds, neurovascular injuries and compartment syndrome
- Early analgesia, antibiotics if indicated and ADT (tetanus immunisation)
Q4. How would you recognize and manage a traumatic amputation from extremity trauma?
An amputation is an injury that results in loss of the extremity distal to the wound.
- Usually obvious!
- Check for associated neurovascular complications and crush injuries. Bleeding may be slight, thanks to arterial spasm. Severed nerves are exquisitely painful.
- Determine the time of injury. Reimplantation is less likely to be successful if warm ischemia time exceeds 6 hours (in general), but success has been achieved at up to 24+ hours.
- X-ray the amputated part and the stump to help determine the extent of injury and viability
- Consult surgery (may require general surgeon, plastics and/ or orthopedics)
- Always treat an amputated part as if it may be reimplanted. It may at least be useful for achieving skin coverage of a wound.
- Handle the amputated part with care, do not debride it, irrigate with normal saline and pack loosely with sterile saline soaked gauze. Place in a water-tight plastic bag and store in an ice water slurry. Ensure ice does not directly contact the amputated part.
- Irrigate the stump with saline and control bleeding with direct pressure.
- Give AAA treatment: prophylactic IV antibiotics (e.g. cephazolin), analgesia and update ADT.
Q5. What circustances favour reimplantation of an amputated body part?
Consult a surgeon early so that they can make the decision whether or not to reimplant. Always treat an amputated body part as if it is a candidate for reimplantation.
Reimplantation is more likely to be performed for:
- Short ischemia time (1 hour of warm ischemia equals 6 hours of cold ischemia)
- Thumb and index fingers are usually reimplanted
- Multiple amputations
- Dominant limb involved
- Patient’s occupation depends on motor skills
- Upper limb amputations are more likely to be reimplanted than lower limb amputations, as effective prostheses are more available for the latter and they are more likely to have crush injuries
A major trauma patient requiring resuscitation and emergency surgery is generally not a candidate for reimplantation.
Q6. How would you recognize and manage neurological compromise due to limb injury?
- suspect nerve injury if vascular injury is present, as nerves tend to run in close proximity
- detailed motor and sensory exam distal to the injury site: e.g. loss of function, weakness, areflexia, paraesthesiae, sensory loss.
- consider coexistent vascular injury, compartment syndrome and associated fracture
- consult orthopedic surgeon (or hand surgeon or plastic surgeon as appropriate)
- treat compartment syndrome if present
- reduce and splint fractures
- elevate limb to decrease edema
- rest affected limb in position of function
- most closed soft tissue injuries with neurological injury gradually resolve over 3 months
- transected nerves require operative repair, usually within 24 hours — unless minor sensory alterations only, which may be followed up at 1 week
Q7. How would you recognize and manage a degloving injury?
Degloving injuries involve separation of the skin and underlying subcutaneous connective tissue from the underlying fascia. They are usually but not always open injuries causing exposure of the underlying structures. They are associated with high morbidity.
- usually easily identifiable by exposure of underlying fascia hat invests muscles, vessels, nerves and bone
- closed degloving injuries may not be obvious and are often missed on initial assessment – suspect based on mechanism (e.g. run over by motor vehicle, limb caught in heavy machinery) that involves shearing forces and subcutaneous swelling suggesting underlying hematoma and tissue injury
- assess distal perfusion and neurological function
- x-rays to look for fractures and foreign bodies
- ultrasound may show underlying hematoma, soft tissue disruption and foreign bodies
- consult orthopedic or plastic surgeon urgently
- clean and cover wounds with saline-soaked dressings
- AAA treatment: analgesia, antibiotics, ADT if needed
- splint and elevate limb
- preserve amputated parts
- treat associated injuries and complications (e.g. fractures, dislocations, compartment syndrome, crush syndrome)
- surgical treatment aims to achieve coverage by replacing the degloved tissue or through use of flaps or skin grafts to prevent necrosis of underlying structures
- closed degloving injuries may be treated by washout and drainage of the subcutaneous tissues followed by compression bandages if the overlying tissues are viable.
Q8. Describe your overall approach to major trauma involving a limb injury
Concurrent assessment and management in an appropriately staffed and equipped trauma bay, involving activation of the trauma team and a coordinated team-based approach.
- ABCDE approach with cervical spine immobilisation if indicated
Address life threats
- pelvic fracture with major hemorrhage — apply pelvic binder, hemostatic resuscitation, correct coagulopathy
- major arterial hemorrhage — direct pressure, tourniquet, elevate, hemostatic resuscitation, correct coagulopathy
- crush syndrome — fluid resuscitation to keep urine output > 1-2 mL/kg/h, treat hyperkalemia
Address limb threats
- open fractures — clean and cover wounds, reduce fracture, splint and elevate limb, antibiotics
- compartment syndrome — assess compartment pressures and neurovascular status, remove constrictions,arrange for fasciectomy
- amputation — preserve amputated part (clean, wrap in saline-soaked gauze, keep on ice), clean and cover wound, antibiotics, consider reimplantation
- vascular injury — assess for hard and soft signs, measure ABI, consider CT angiogram and surgical intervention
(see Trauma Tribulation 030 — Trauma! Extremity Arterial Hemorrhage)
- neurological injury — assess neurovascular status, reduce fractures and relieve constrictions, consider surgical repair
- degloving injury — clean and cover wounds, antibiotics
Supportive care and monitoring
- AAA treatment: analgesia (early!), antibiotics (in severe open injuries), ADT (if tentanus immunisation is indicated)
- splint and elevate injured extremity
- FASTHUGS IN BED Please! (as needed)
- seek and treat other injuries (e.g. tendon rupture)
- seek and treat complications (e.g. compartment syndrome, neurovascular compromise)
- urgent surgical consult for assessment, admission and operative intervention
- transfer to a specialist trauma center if appropriate
Textbooks and Journal Articles
- Fildes J, et al. Advanced Trauma Life Support Student Course Manual (8th edition), American College of Surgeons 2008.
- Legome E, Shockley LW. Trauma: A Comprehensive Emergency Medicine Approach, Cambridge University Press, 2011.
- Marx JA, Hockberger R, Walls RM. Rosen’s Emergency Medicine: Concepts and Clinical Practice (7th edition), Mosby 2009. [mdconsult.com]
- Newton EJ, Love J. Acute complications of extremity trauma. Emerg Med Clin North Am. 2007 Aug;25(3):751-61, iv. PMID: 17826216.