[Planning and design of European prospective randomized trial on the value of drain in parotidectomy].

Introduction: There are no valid clinical studies on the value of wound drains in parotid surgery. The aim of the current trial is to analyze the influence of the closed wound drain (redon) on the incidence of postoperative complications such as bleeding, wound healing problems, infection, as well as salivary cyst and fistula after superficial or partial parotidectomy.

Methods: A European-wide multicenter prospective randomized study was planned. The study protocol was prepared by the leading study center (ENT University Hospital Cologne) in cooperation with the ENT University Hospitals Jena and Göttingen. The calculation of the number of cases was carried out with G*Power. The study includes test persons with an indication for parotidectomy for a benign tumor without known coagulation disorder or ongoing anticoagulation. Preoperative randomization and data management is software-supported (REDCap 9.1.24, Vanderbilt University).

Results: The study has been approved by the leading ethics committee in 10/2019 and is open since 04/2019. Currently, nine (9) ENT hospitals are participating in the study, 6 of them in Germany and 3 in Austria. Enrollment of patients is ongoing in 7 centers. With a calculated follow-up-to-treat population of 800 test persons, the planned duration of the study is 4 years.

Conclusions: The Redon-study is the first prospective randomized study worldwide to investigate the effect of a drain in parotidectomy. In order to achieve the recruitment goal within the planned time frame, the participation of further specialized study centers is needed. We also encourage all ENT physicians to make their patients aware of the Redon study, inform them about the possibility of participating in the study and refer them to one of the participating centers.