Compartment Syndrome, Fractures and Early Mobility

Acute Compartment Syndrome: Assessment, Pressures, and Decompression

Compartment syndrome occurs when increased tissue pressure within a closed fascial space compromises capillary perfusion and tissue viability. In an alert critical care patient, the earliest and most reliable clinical sign is severe pain that is out of proportion to the underlying injury. A related early finding that raises immediate concern is pain elicited during passive stretching of the affected muscle groups, which warrants urgent clinical escalation. Paresthesia may also develop early as sensory nerve fibers experience initial hypoxia, eventually advancing to diminished sensation as nerve ischemia progresses.

Normal intracompartmental pressure is generally about 0 to 10 mmHg. An absolute compartment pressure above 30 mmHg must always be interpreted alongside the patient's systemic perfusion pressure and clinical findings, while a delta pressure of 30 mmHg or less raises strong concern for acute compartment syndrome and warrants urgent provider evaluation. Critical care nurses must recognize that pallor, paralysis, and pulselessness represent concerning late findings. The presence of intact distal pulses does not rule out the condition, nor do these late findings alone establish irreversible tissue necrosis.

When managing suspected acute compartment syndrome, the nurse must position the affected extremity at heart level to maintain perfusion without increasing venous hydrostatic edema. Elevating the limb above heart level is strictly contraindicated because it reduces arterial inflow pressure, and applying ice or cold compresses is equally contraindicated due to cold-induced vasoconstriction exacerbating underlying ischemia. The nurse should promptly relieve removable external constriction within protocol and urgently notify the provider so any constrictive cast or splint can be split or removed. Emergency decompressive fasciotomy is the definitive medical intervention to preserve neuromuscular function, after which the nurse monitors wound viability, documents frequent distal neurovascular checks, and tracks systemic fluid losses from exposed tissues.