A Novel Vascular Reconstruction Technique for Limb Salvage Surgery Using Temporary Bypass Tubes

Abstract

Sir: The techniques and concepts of limb salvage for soft-tissue sarcoma of the lower limb involving major vessels have been substantially developed in recent years.1–3 We present a novel vascular reconstruction technique for limb salvage surgery using temporary bypass tubes. A temporary bypass tube (Anthron; Toray Industries, Tokyo, Japan) has been designed for use before excision of soft-tissue sarcoma involving major vessels in the extremities. The tube is constructed of polyvinylchloride coated with a heparinized hydrophilic polymer (Anthron).4 The rate of heparin release from the polymer is 10–2 U/cm2/minute, sufficient to prevent intracatheter coagulation without requiring administration of systemic anticoagulants. Both ends of the tube are tapered to facilitate insertion of the bypass tube into vessels. Nambisan and Karakoisis2 showed the standard steps in extensive resection of sarcoma of the extremity involving major vessels. After proximal and distal exposure of the vessels, dissection around the muscles to be removed along with the tumor is undertaken, and the origins and insertions of these muscles are divided. The last step in resection, following heparinization, is to clamp and divide the vessels proximally and distally. We used to perform the operation in the same manner described by Nambisan and Karakoisis.2 However, we encountered several cases in which control of hemorrhage from soft tissue surrounding the tumor was difficult. We therefore attempted to use temporary bypass tubes before and during extirpation of the whole tumor (Fig. 1). This procedure provided an almost bloodless field during dissection. This bypass procedure using an Anthron tube served as a pneumatic tourniquet to which we have become accustomed, facilitating reductions in hemorrhage, easy dissection, and time savings. Finally, this maneuver provides a lower incidence of infection, which can be quite high during extensive resections that require prolonged surgery. However, the tube courses beyond the operative field, and the natural warp of the tube serves to keep the tube away from the tumor still connected around abundant soft tissue. This facilitates handling during tumor dissection. After extirpation of the tumor keeping with bypass, the contralateral greater saphenous vein is harvested. Vascular defects are reconstructed using vein grafts (Fig. 2). During vein harvesting and graft preparation, there was no concern regarding limb ischemia.Fig. 1.: A large liposarcoma in the anterior region of the right thigh (asterisk). Anthron bypass tubes were substituted for the superficial femoral artery (single arrowhead) and vein (double arrowheads).Fig. 2.: After extirpation of the tumor keeping with bypass, the contralateral greater saphenous vein is harvested. Vascular defects of the superficial femoral artery vein were reconstructed using vein grafts.The tapered type tube can maintain blood flow at 230 ml/minute under a 20-cm H2O blood pressure discrepancy. Given the high blood flow through the femoral artery, holding the inserted tube and vessels by anchoring them with thick silk sutures and clamping them with bulldog forceps is a key step to achieving success in this procedure. No thrombus formation in the catheter was detected after use and no complications attributable to the catheter were observed. Limb salvage surgery using the Anthron bypass tube facilitates reductions in ischemia time, operation time, and infection rate. We have proposed a new technique with which to obtain a bloodless operative field in the proximal extremity using the bypass tube. This technique appears useful for resecting tumors with adequate surgical margins and achieving local control of the disease. Noriaki Kikuchi, M.D., Ph.D. Division of Plastic and Reconstructive Surgery Department of Orthopaedic Surgery Toshihisa Osanai, M.D., Ph.D. Department of Orthopaedic Surgery Takashi Tsuchiya, M.D., Ph.D. Department of Orthopaedic Surgery Yamagata University School of Medicine Hiroshi Orui, M.D., Ph.D. National Sanatorium of Yamagata Clinic Toshihiko Ogino, M.D., Ph.D. Department of Orthopaedic Surgery Yamagata University School of Medicine Yamagata, Japan