Soft Tissue Trauma

Assessment of soft tissue injury is critical in the management of a trauma patient. Muscular coverage is necessary for the viability of any orthopedic repair, but it may be jeopardized by avulsion at the time of injury, ischemia from elevated compartment pressure, and ongoing bacterial infection in open wounds. Acute surgical management of soft tissue injury is straightforward: all dead or devitalized tissue must be débrided away and the wound thoroughly irrigated to reduce the load of bacterial contaminants. When muscle or fascia involvement is significant, serial débridement at 1- to 3-day intervals is necessary to establish a margin of completely viable tissue. Vacuum dressings for large soft tissue wounds are gaining in popularity because continuous negative pressure over the wound surface removes contaminants and encourages blood flow. When serial débridement establishes viable tissue at all margins of the wound, arrangements for definitive closure can be made. Definitive closure may be as simple as a split-thickness skin graft or as complex as a free tissue transfer of muscle and fascia from an uninjured portion of the body, with attendant arterial and venous anastomoses.

Superficial vacuum dressings can be changed at the bedside under light sedation, but patients with deep wound dressings will require general anesthesia. The need for repeated surgery is an important consideration for the anesthetic technique. When otherwise appropriate, the use of continuous epidural catheters for both analgesia and operative anesthesia can greatly facilitate the care of these complex patients. Anesthesia for free tissue transfer surgery requires meticulous attention to detail because these operations can be quite protracted. Every effort should be made to facilitate perfusion of the grafted vessels, including keeping the patient warm, euvolemic, and comfortable and maintaining the hematocrit in the rheologically favorable range of 25% to 30%. The use of epidural anesthesia and analgesia is controversial, with some surgeons favoring it for its vasodilatory effects and others concerned that it will induce a "steal" phenomenon that will actually limit flow in the denervated free tissue.^[193]

Amputation is occasionally necessary for massive crush injury, vascular injury, or progressive soft tissue infection. Anesthetic management is notable for the strong emotional overlay that accompanies this operation. Whereas regional anesthesia is physiologically appropriate and has been shown to limit the subsequent development of phantom limb pain, very few patients will be accepting of such anesthesia. General anesthesia is usually required, although combining it with epidural analgesia may confer the benefits of both techniques.