Physiological changes in venous hemodynamics associated with elective fasciotomy

It has been postulated that lower extremity fasciotomy may disrupt the calf musculovenous pump and predisposes to development of chronic venous insufficiency (CVI). However, studies based on trauma patients who undergo emergent fasciotomy are confounded by the possibility of concomitant vascular and soft tissue injury and use historical controls. This is a prospective study that evaluates venous hemodynamics in young patients undergoing elective fasciotomy for chronic exertional compartment syndrome (CECS), eliminating the problems associated with retrospective study of trauma patients. CECS was diagnosed by history and, when indicated, measurement of compartment pressures. Prior to elective two- or four-compartment fasciotomy, each patient underwent lower extremity air plethysmography (APG) and colorflow duplex ultrasonography. These studies were repeated a minimum of 6 weeks postoperatively. Fifteen patients who had fasciotomies for CECS were studied; two of these patients had bilateral fasciotomies for a total of 17 limbs. There were 13 male and two female patients (average age 31.2 years). APG and colorflow duplex were performed an average of 12 weeks after fasciotomy. Outflow fraction, venous volume, and ejection volume showed no significant changes postoperatively. However, the venous filling index (VFI) increased (0.9 +/- 0.1 vs. 1.1 +/- 0.1 mL/sec; p < 0.05, paired t-test), the ejection fraction tended to decrease (59 +/- 4% vs. 52 +/- 2%; p < 0.08, paired t-test), and the residual volume fraction (RVF) increased (26 +/- 3% vs. 36 +/- 5%; p < 0.05, paired t-test). There were no patients with evidence of deep venous reflux. Two extremities with preoperative greater saphenous vein (GSV) reflux did not worsen, and three extremities developed new GSV reflux following fasciotomy, although VFI remained normal in each extremity. Elective fasciotomy for CECS does not lead to significant venous reflux but likely does diminish calf muscle pump function and increases RVF moderately in young adult patients. With longer follow-up this diminished calf muscle pump function may increase the risk of CVI.