Fixation of Skin Flaps after Mastectomy Using Running or Interrupted Sutures for Combatting Seroma: A Protocol for a Randomised Controlled Trial (ANNIE).

Introduction: Flap fixation significantly reduces the incidence of seroma formation after mastectomy. Previous studies have compared running sutures, interrupted sutures, and tissue glue application with conventional wound closure. A recent systematic review with network meta-analysis showed running sutures to be the most optimal technique; however, direct comparisons and high adequate scientific evidence are lacking. This prospective trial aimed to directly compare running sutures with interrupted sutures to determine which technique of flap fixation using sutures is superior.

Methods: This trial will combine a retrospective cohort of patients undergoing flap fixation using interrupted sutures from a previous trial, with a randomised prospective cohort with patients undergoing flap fixation using running sutures or flap fixation using interrupted sutures. This study design was chosen to acquire a sample size with sufficient power and the ability to conduct this study in an acceptable time frame. The primary endpoint is the incidence of complications requiring interventions, including clinically significant seroma, infections and haemorrhagic complications. Secondarily, the length of the procedure and cosmetic results will be compared.

Conclusions: This is the first trial comparing two suturing techniques for flap fixation after mastectomy. Results will be used to optimise flap fixation techniques for these patients to prevent seroma formation.