Antiseptic Skin Agents to Prevent Surgical Site Infection After Clean Implant Surgery: Subgroup Analysis of the NEWSkin Prep Trial

There remains debate as to the ideal skin preparation agent to prevent surgical site infection (SSI) after clean implant surgery. This study is a subgroup analysis of all patients undergoing implant surgery in the NEWSkin prep trial. The NEWSkin prep trial is a randomized clinical trial (RCT; n = 3300) comparing the three antiseptic skin preparation agents commonly used prior to incisional surgery: chlorhexidine with alcohol (C-Alc), povidone iodine with alcohol (PI-Alc), and aqueous povidone iodine (PI-Aq). All participants who underwent clean incisional surgeries with implants from this trial were selected for analysis. The primary outcome was SSI rate; secondary outcomes were complication rates and re-admission rates. A total of 712 patients in the NEWSkinPrep study underwent clean implant surgery between January 2015 and December 2018. Randomization resulted in the following distribution: C-Alc, 238; PI-Alc, 243; and PI-Aq, 231. Median age of participants was 63 years and 41% were female. Surgical site infection rates were: C-Alc, 10.13%; PI-Alc,11.52%; and PI-Aq, 11.26%. Povidone iodine with alcohol did not appear to be non-inferior to C-Alc (mean difference, 1.39%; 95% confidence interval [CI], -4.17 to 6.95) and PI-Alc was not superior to PI-Aq (mean difference, 0.27%; 95% CI, -5.45 to 5.99; p = 0.9271). There were no differences seen in secondary outcomes between groups. These results indicate a similarity between PI-Alc and C-Alc and that PI-Alc was not superior to PI-Aq. Because this study was not powered to assess these differences in clean cases with implants, additional studies are needed to assess these agents.