Standardized video-endoscopy and surgical field grading scale for endoscopic sinus surgery: a multi-centre study.

Background: Bleeding is a major concern in endoscopic sinus surgery (ESS), as it may impede surgical progress and is often associated with complications. To improve the study and management of intraoperative bleeding, a standardized method of recording bleeding during ESS is needed. The aim of this study was to develop a standardized method of documenting bleeding in ESS and of grading the surgical field.