Povidone-iodine vs Saline Solution in Colorectal Surgeries and Its Effects on the Surgical Site Infection

Patients will be randomized to one of the following intervention groups:

Group 1: intraoperative irrigation/washing of the surgical incision with povidone-iodine (PVP-I); Detail: after aponeurotic synthesis and immediately before cutaneous synthesis, the skin and subcutaneous tissue of the surgical incision will be irrigated and washed abundantly with approximately 500ml (depending on the size of the incision) of povidone-iodine solution (PVP-I). The exact volume to be used will be the minimum volume necessary for abundant and efficient washing of the incision tissues. " Group 2: intraoperative irrigation/washing of the surgical incision with saline solution (NaCl 0.9%); Detail: after aponeurotic synthesis and immediately before cutaneous synthesis, the skin and subcutaneous tissue of the surgical incision will be irrigated and washed abundantly with approximately 500ml (depending on the size of the incision) of saline solution (NaCl 0.9%). The exact volume to be used will be the minimum volume necessary for abundant and efficient washing of the incision tissues.

NOTE: other care routines for participating patients will not be changed by this study. Patients will receive mechanical colon preparation and antibiotic prophylaxis according to routines already in place by the assistant team.

Randomization: the block randomization method will be used (blocks of 4 patients each).

Groups 1 and 2 will be compared with each other regarding the outcomes.

Inclusion criteria

Patients older than 18 years of age diagnosed with benign or malignant colorectal diseases undergoing elective open or video-assisted colectomy or proctectomy (resection) at the Hospital de Clinicas de Porto Alegre - Division of Coloproctology.

Exclusion criteria

• age under 18;
• surgery classified as dirty;
• urgent/emergency surgery;
• patients undergoing multi-visceral resections (pelvic exenteration or partial resection of any adjacent organ);
• known allergy to iodine.