A 55 year-old morbidly obese female was brought in by EMS after a mechanical fall at home. She sustained the above distal tib-fib fracture while attempting to stand up. No LOC reported, and she is not taking any blood thinners or antiplatelet agents.
On Arrival, BP 160/90, HR: 110 regular, RR: 22, Afebrile
Exam reveals a morbidly obese female in mild distress secondary to right lower extremity pain, Cardiopulmonary exam is unremarkable. There is bilateral chronic edema to the lower extremity, and right lower extremity tenderness to palpation over the distal shin but no gross deformity. Peripheral pulse exam is limited by body habitus but the extremities are warm, dry, with soft compartments.
Lab results reveal an elevated creatinine (nearly doubled from baseline), Potassium of 5.8 (no ECG changes), a mild elevation of AST to 70, and a CPK of approximately 4000.
Questions:What is the underlying diagnosis?
The most likely diagnosis in this case is acute rhabdomyolysis.
What are possible complications?
Important complications include but are not limited to:
- Compartment syndrome
- Electrolyte and acid-base balance disorders
- Fluid shifts with large volume fluid sequestration
- Acute kidney injury with all associated complications->hyperkalemia, hyperphosphatemia, metabolic acidosis, fluid overload, uremia
- Disseminated intra-vascular coagulation.
What is your ED management?
Aggressive fluid resuscitation is key to prevent some of the complications listed above. Starting normal saline a rate titrated to produce a urine output of approx 200ml/hr should be the goal. This implies that close monitoring of the urine output should be ordered. If despite aggressive intra-venous resuscitation, a urine output this high cannot be achieved, agents such as mannitol can be considered. In this case the cause of rhabdomyolysis is obvious and the appropriate orthopedics consultation for fracture management and monitoring for potential development of acute compartment syndrome should be placed. All of this should be occurring while monitoring for potential emergent indications for renal replacement therapy in the case of AKI related complications that are refractory to medical management.
The following paper is a great review of ED management of acute rhabdomyolysis.
Parekh, Ram. Rhabdomyolysis: Advances in Diagnosis and Treatment. Emergency Medicine Practice. March 2012 14(3):1-16.