November 2001

By James R. Roberts, MD

An unconscious 28-year-old man was brought to the emergency department (ED) after suffering a multiple drug overdose. Last seen 12 hours earlier, he had been found lying on a hardwood floor. The patient had an obvious aspiration pneumonia, was hypoxic and hypotensive, and required intubation and assisted ventilation. He was also in renal failure. Physical examination revealed swelling and bruising on the inner aspect of the left arm (see photo, above). A dipstick urinalysis revealed the presence of blood but no erythrocytes, findings that pointed to rhabdomyolysis and renal failure, for which the alert physician administered the appropriate therapy.

Because the patient was unconscious and undergoing intubation, he obviously could not express any complaints. Upon examining the patient's arm, the physician determined that a good radial pulse was present. The multiple medical problems logically prompted the treating physicians to focus on the respiratory, cardiovascular, and renal conditions. After the patient was settled in the intensive care unit, a curious nurse noted a diminished pulse and asked the physicians to examine the arm again. What did that second look reveal?

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The patient had sustained a crush injury from lying for many hours on his left side with his arm tucked under the torso. The compression produced rhabdomyolysis of the arm, the cause of the renal failure, but it also created enough pressure and subsequent swelling to induce compartment syndrome. The patient's unconscious state precluded any complaint of pain, and the other life-threatening conditions took precedence over the supposed "benign pressure burn."

The extent of the compartment pressures mandated an immediate fasciotomy (see photo, above). The patient subsequently required additional débridement of devitalized muscle, a skin graft, and many hours of physical therapy. If he had been able to speak, the patient would likely have complained of intense pain, weakness, paresthesia, and numbness of the arm and hand, as well as pain when the muscles were passively stretched.

The initial presence of a radial pulse had led the physicians to assume that circulation was adequate. However, the problem was not with the distal pulse but with local ischemia in the muscle mass of the arm. The distal pulse is the last sign to disappear, and simply monitoring the pulse is not sufficient to determine the presence or absence of a proximal compartment syndrome. Unfortunately, a fasciotomy would have been necessary regardless of the time of diagnosis, and whether earlier intervention would have produced a better outcome remains unclear.

Emerg Med 33(11):12, 2001

Dr. Roberts is professor of emergency medicine at the Medical College of Pennsylvania and chairman of the department of emergency medicine at Mercy Catholic Medical Center in Philadelphia. He is also a member of the Emergency Medicine editorial board.