PC47. Physiologic Effects of Thoracic Duct Lymphovenous Bypass

PURPOSE: The lymphatic system is still largely enigmatic, but mechanical obstruction at the thoracic duct is one pathology we are starting to treat well. Patients with thoracic duct obstruction who have failed conservative treatment as well as minimally invasive therapies may be candidates for microsurgical lymphovenous bypass. At our institution, we have developed a multidisciplinary, collaborative intraoperative protocol with interventional radiologists. Postoperatively, lymphovenous bypass is thought to cause physiological derangements as a result of the increased venous return, but no data exist on specifically what changes can be expected. We herein report on a case series of thoracic duct lymphovenous bypass patients and their postoperative physiologic changes. METHODS: A retrospective review of all nonsyndromic adult patients who underwent thoracic duct lymphovenous bypass by the senior authors from 2016-2021 was performed. Demographic, preoperative, perioperative, and postoperative data were collected. Postoperative changes in vital signs including oxygen requirements, heart rate, and blood pressure were analyzed. RESULTS: Nine patients were included in the study. Immediate postoperative heart rate increased significantly among this heterogeneous patient population, but within 4 - 6 hours the change in heart rate was no longer significant. Mean arterial pressure and oxygen requirement were not significantly different before and after bypass. CONCLUSION: Thoracic duct lymphovenous bypass appears to be well tolerated in the short-term even in patients with cardiopulmonary comorbidities. Further data are necessary to continue to better understand the resulting physiologic changes and to optimize patient outcomes.