Mangled Extremity- Keep or Cut?
A 42-year-old male was struck by a vehicle as he was crossing the street. He was brought in by EMS. He had a depressed GCS and unequal pupils, and he was intubated for concern for airway compromise. He had a significant injury to the right lower extremity with diffuse bleeding, but no active arterial bleeding. Compressive dressings were applied. He had fluid in the LUQ window of his FAST. He was hemodynamically unstable.
Initial evaluation and management? Imaging?
Poly-trauma patients demand prioritization and quick decision making, and the simple step-wise algorithms designed for each injury in isolation are less helpful. Patients with blunt abdominal trauma and hemodynamic instability require emergent operative intervention. Patients with a depressed GCS and an abnormal pupil exam require emergent CT imaging to define the severity of their head injury and consultation with neurosurgery. Patients with a mangled extremity require a CT scan to define the vascular injury.
In the setting of blunt abdominal trauma, a positive FAST and hemodynamic instability, he was transported to the OR emergently. If there was an option for a rapid CT en route to define his TBI, that would have been ideal. But hypotension is associated with worse outcomes for TBI patients, so the priority is stopping the bleeding. We performed a midline laparotomy, splenectomy, and repaired a diaphragm injury. We placed a temporary abdominal closure.
Intraoperative Image
What do we do about his mangled lower extremity? Consult vascular or ortho? Ex-fix? Amputate?
There are several important tasks. Assessment of injury to neuromuscular structures is vital. If possible, rapid restoration of arterial blood flow is beneficial. However, it is vital to evaluate the need for amputation. This decision requires consideration of current physiologic status, co-morbidities, and baseline functional status. It's sometimes a question of life versus limb. Orthopedic and vascular specialists can be consulted, but it is important not to lose sight of the patient's overall clinical status. A brief temporizing procedure to restore blood flow with a shunt, stabilize bony structures, and preserve any remaining soft tissue may be appropriate, but a lengthy vascular repair and bony fixation are likely not ideal.
The patient's baseline functional status, social support, and co-morbidities were unknown. Based on the severity of his extremity injury, high injury burden, and need for urgent head CT, my recommendation was for immediate amputation. This decision requires weighing the risks/ benefits of limb salvage (prolonged time in the operating room for stabilization, risk of ongoing tissue ischemia leading to systemic complications) vs amputation (limb loss). Our orthopedic specialists felt they could salvage his limb, and give him a chance to be an active participant in the decision-making. We agreed to a time limit to minimize operative time, so the limb was stabilized temporarily with a plan for ongoing evaluation of the limb viability.
Managment of the Mangled Extremity
Management of patients with mangled extremities remains controversial. Severe scoring systems have been created, with variable success in predicting who requires amputation.
In the acute setting, the trauma surgeon must weigh the risks and benefits of limb salvage versus immediate amputation. If the limb injury is devastating (perhaps only hanging on by a small skin bridge), and the patient has other injuries that require immediate intervention, rapid amputation can be life-saving.
If the decision to amputate is less clear, a second opinion from a colleague and orthopedics should be elicited. There have been remarkable advances in the ability to restore function to mangled extremities, and discussion with specialties can be very helpful.
"Therapeutic advances in the treatment of vascular, orthopedic, neurologic, and soft tissue injuries have reduced the diagnostic accuracy of the MESS in predicting the need for amputation. There remains a significant need to examine additional predictors of amputation following severe extremity injury."
Loja, Melissa N et al. “The mangled extremity score and amputation: Time for a revision.” J Trauma Acute Care Surg. 2017;82(3):518-523
The trauma surgeon must maintain perspective on the whole patient- spending hours doing meticulous vascular or nerve dissection/ repair or extensive orthopedic manipulation can be an intolerable burden on a patient with multiple other injuries.
1. Control active hemorrhage.
2. Restore anatomic limb alignment.
3. Assess distal arterial flow→ evidence of vascular injury→ CTA to characterize injury.
4. Assess neurologic function.
Unable to control active hemorrhage or there is hemodynamic instability→ proceed to OR.
Assess for the need for immediate amputation. Factors to consider:
Complex, segmental, severely comminuted fracture.
Large circumferential soft tissue loss or massive soft tissue necrosis.
Compartment syndrome with myonecrosis.
Nerve disruption.
Massive contamination.
Prolonged warm ischemia >6 hours. Poor distal anastomosis options.
No immediate amputation→ intraluminal shunt to re-establish perfusion. Then assess bony and nerve injury. Evaluate risks/ benefits of limb-preservation.