Crush Injury on a Four-Hour Carry
A rural warrant service in mountainous terrain ends with the subject barricaded in a cinderblock workshop. During the tactical approach, a wall section collapses and pins both of his lower legs for 45 minutes before the team can lift it. You reach him at 14:10. He is 45 years old, awake but lethargic, with crushed calves, mottled feet, and no palpable distal pulses. HR 128, BP 88/54, RR 26, SpO2 96%. He has had no urine output since extrication. The nearest ambulance cannot reach the site; your litter team must carry him 2.5 miles to a landing zone, about four hours. Ambient temperature is 4 degrees Celsius with steady rain. You carry IV fluids, ketamine, morphine, TXA, a pelvic binder, and a monitor, but no blood products.
1. Outline your fluid plan before, during, and after release of the crush, including how you will monitor for hyperkalemia in an austere setting.
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Crush syndrome kills through hyperkalemia and hypovolemic shock when the pressure is released. I start isotonic crystalloid before the wall is lifted if that is possible. Normal saline is my preference here because it contains no potassium; I give roughly 1 liter per hour, or a 1-liter bolus then 500-1,000 mL/hr, titrated to a systolic pressure near 90 and to urine output if a catheter is placed. I continue the fluids during and after release, because reperfusion can drop the pressure abruptly. In an austere setting I monitor for hyperkalemia with continuous ECG: peaked T waves, widened QRS, bradycardia, or a sine-wave pattern. I have calcium chloride or gluconate ready for ECG changes, and nebulized albuterol as an adjunct. I do not rely on a lab. Dark urine, oliguria, and mottled feet support rhabdomyolysis, so I keep fluids running and document the time of release as the key event.
2. Build an analgesia and sedation plan for a four-hour litter carry. Explain drug choices, dosing considerations, and monitoring.
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For a four-hour litter carry I want analgesia that is potent but does not drop his blood pressure or respirations. Ketamine is my first choice: 0.3 mg/kg IV boluses for pain, repeated as needed, or an infusion at 0.1-0.3 mg/kg/hr. If IV access is lost, 0.5-1 mg/kg IM works. For a painful litter move I may use a dissociative dose of 1-2 mg/kg IM, but only with someone dedicated to airway monitoring. Morphine 2-4 mg IV titrated is an alternative, but it can cause hypotension and respiratory depression, and it accumulates in shock. I avoid NSAIDs because of the renal injury risk. I reassess pain, sedation, respiratory rate, and blood pressure after every bolus, and I keep naloxone available. The goal is a patient comfortable enough to lie still while protecting his airway and perfusing his brain, not a patient unconscious from stacked sedatives.
3. What complications do you anticipate in hours 1-4, and what triggers would make you request a hoist or a faster evacuation?
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In hours 1-4 I expect hyperkalemia, hypothermia, compartment syndrome, worsening rhabdomyolysis, and shock. I monitor ECG, mental status, urine color and output, and core temperature; I keep him covered and off the wet ground. A change in ECG, a systolic below 90 despite fluids, a falling GCS, or a temperature below 35 degrees Celsius means he needs faster evacuation. I would request a hoist or a closer landing zone if the terrain allows, because a four-hour carry with a crush injury is a long time to manage hyperkalemia without labs. If he develops a wide-complex rhythm, I treat for hyperkalemia with calcium and expedite. I also document tourniquet times, fluid volumes, and drug doses, because the receiving team will need them.