Role of Continuous Local Infusion of Ropivacaine for Post-Operative Pain Management in Patients Receiving Osseocutaneous Free Flaps

Head and neck oncologic surgery often requires the use of free tissue transfer, or microvascular reconstruction, to reconstruct defects created by tumor resections. Although there are several techniques for the reconstruction of defects, resection of large tumors leave defects that require the transfer of vascularized tissue from one part of the body to repair the defect. For example, the removal of a segment of diseased mandible requires free tissue transfer containing the component parts - skin, muscle, and bone - to reconstruct the deficit created by the resection of the tumor. Over the years, microvascular surgeons have focused their attention on maximizing the success of these technically difficult surgeries. However, now, with free flap reconstruction rates in excess of 95%, surgeons are afforded the opportunity to turn their focus toward the morbidities associated with these surgeries. While much has been published about donor site wound healing, pain control in the post-operative period has largely been neglected in the head and neck reconstruction literature. Systemic analgesia with opioids is standard of care, which has been shown to lead to increased confusion, significantly increased length of stay and increased risk of pulmonary complications. In addition, it has been shown that early mobilization and optimal wound care can decrease donor site morbidity.

In this study the clinical team aims to better control donor site pain utilizing local, targeted analgesia to relieve pain at the donor site for osseocutaneous free-flaps. To reduce confounding and bias, the study will be a double-blind prospective randomized placebo controlled trial wherein patients undergoing osseocutaneous free flap surgery will be randomized to receive continuous infusion of ropivacaine or normal saline (placebo) via local continuous infusion catheter, which will be placed intraoperatively at the time of donor site closure. Patients' pain will be monitored for the first 48hrs after surgery. Donor site and global pain at rest will be evaluated every 8 hours for the first two postoperative days using a visual analogue pain scale (VAS). Essentially, there is a 100 millimeter line drawn on a piece of paper, with "no pain" marking the left end of the line and "worst pain" marking the right end of the line. Subjects mark with a pen along the line where pain is felt fits along that continuum. A researcher then measures how far along the line that mark is placed and then it is recorded. Median daily opiate use via PCA will also be tracked. Donor site-specific range of motion and strength will be assessed with a formal physical therapy evaluation on post-operative day 2 or soonest non-holiday weekday. Information on patient satisfaction, time to ambulation, and length of stay will also be collected. Subgroup analysis will be performed.