We are grateful to Drs. Turnbull and Mills for noting a number of factors to consider when discussing the issue of perioperative compartment syndrome that is not associated with obvious etiologic factors, such as thromboembolic or traumatic arterial or venous occlusions. This problem is indeed quite rare. 1The combined rarity of the event and the multiple, potential contributing factors make it very difficult to draw conclusions about etiologic factors. Therefore, we believe it is best to perform studies to elucidate isolated factors before drawing any comprehensive conclusions.
Our study specifically focused on the effects of a sequential pneumatic compression device on pressures in the tibialis anterior muscle compartment of awake volunteers in the lithotomy position. 2We found that the use of the compression device decreased intracompartmental pressures, making no comment about its effects on intracompartmental blood flow. Yes, Chase et al. 3have very nicely shown that anterior leg compartment pressures increase when anesthetized patients are placed in the 45° lithotomy position with consistent use of Allen supports and sequential compression devices, especially for prolonged periods. Their study, however, does not address our question about the effects of the compression device on intracompartmental pressures and is irrelevant to our study.
Lower extremity arterial and venous blood flow and many other factors likely affect perfusion and oxygenation of the muscles of the leg compartments. Therefore, we agree with Drs. Turnbull and Mills that it would be premature to conclude that sequential pneumatic compression devices minimize the risk of developing lower extremity compartment syndrome. However, these devices appear to decrease pressures in the anterior tibialis muscle compartment, a finding that contrasts with common (and unproved) wisdom.