Randomized Controlled Trial of Two Alcohol-based Preparations for Surgical Site Antisepsis in Colorectal Surgery.

OBJECTIVE

To compare 2 alcohol-based, dual-action skin preparations for surgical site infection (SSI) prevention in elective colorectal surgery.

BACKGROUND

Colorectal surgery is associated with the highest SSI rate among elective surgical procedures. Although evidence indicates that alcohol-based skin preparations are superior in SSI prevention, it is not clear if different alcohol-based preparations are equivalent in clean-contaminated colorectal procedures.

METHODS

We performed a blinded, randomized, noninferiority trial comparing iodine povacrylex-alcohol (IPA) and chlorhexidine-alcohol for elective, clean-contaminated colorectal surgery. The primary outcome was the presence or absence of SSI, defined as superficial or deep SSI, within 30 days postdischarge. A 6.6% noninferiority margin was chosen.

RESULTS

Between January 2011 and January 2015, 802 patients were randomized with 788 patients included in the intent to treat analysis (396 IPA and 392 chlorhexidine-alcohol). The difference in overall SSI rate between IPA (18.7%) and chlorhexidine-alcohol (15.9%) was 2.8% (P = 0.30). The upper bound of the 2.5% confidence interval of this difference was 8.9%, which is greater than the prespecified noninferiority margin of 6.6%. Other endpoints, including individual SSI types, time to SSI diagnosis, and length of stay were not different between the 2 arms.

CONCLUSIONS

In patients undergoing elective, clean contaminated colorectal surgery, the use of IPA failed to meet criterion for noninferiority for overall SSI prevention compared with chlorhexidine-alcohol. Photodocumentation of wounds and rigorous tracking of outcomes up to 30 days postdischarge contributed to high fidelity to current standard SSI descriptions and wound classifications.