This prospective observational study examines the associations of presence, duration, type, number and location of surgical drains with the risk of surgical site infections in a contemporary and multicentric cohort of general, orthopedic trauma and vascular surgery procedures.

Surgical site infections (SSI) represent the most common type of nosocomial infection amongst surgical patients. They cause morbidity and mortality.

Surgical Drains are commonly inserted at the end of many surgical procedures. In contrast to potential benefits, drains are also thought to potentially serve as a conduit of bacteria into the wound and hence may increase the risk of SSI. Patterns of use of drains vary widely across surgical disciplines and individual practices. There are no uniform guidelines and standards are often rather based on tradition than on evidence. The aim of this large prospective study was to examine the association of presence, duration, type, number and location of drains with the risk of SSI in a contemporary and multicentric cohort of general, orthopedic trauma and vascular surgery procedures.

Inclusion Criteria:

• Inpatients
• Age 18 years or older
• General, orthopedic trauma and vascular procedures
• Surgical antimicrobial prophylaxis

Exclusion Criteria:

• outpatient surgery
• Presence of a contraindication for cefuroxime and/or metronidazole
• preexisting antibiotic therapy within 14 days prior to surgery
• cognitive impairment
• combined operations including other than the above specified surgical divisions
• Emergency procedures with planned incision within 2 hours after indicating the procedure.

This observational study is nested in a multicenter randomized controlled trial that was designed to evaluate the optimal timing of surgical antimicrobial prophylaxis in a general, orthopedic trauma and vascular surgery population. The term "general surgery" refers to gastrointestinal, oncologic breast, endocrine and hernia surgery. The study centers are two tertiarry referral hospitals in Switzerland. All patients included in the randomized controlled trial are included in this observational study as well.