Background: Surgical site infection (SSI) is the common complication after abdominal surgery. Proper use of antiseptic can decrease SSI. According to previous studies, chlorhexidine in alcohol is superior to povidone iodine when using as skin preparation before

abdominal surgery. Due to alcohol is flammable substance, there are many reports shown usage of chlorhexidine in alcohol for skin preparation can cause skin burn. Our study will compare whether chlorhexidine in water superior to povidone iodine as effective antiseptic agent for skin preparation before abdominal surgery.

Objective: The aim of the present study is to compare SSI rate between using chlorhexidine in water and povidone iodine in patient undergoing abdominal surgery.

Materials and Methods: Patients undergoing abdominal surgery by single surgeon (WS) between 1 July 2017 to 30 June 2018 in Ramathibodi Hospital were randomized to use skin preparation with chlorhexidine in water or povidone iodine. The inclusion criteria were elective clean-contaminated abdominal surgery, patient’s age between 18 to 75 years, and patients who signed consent form. Exclusion criteria were history of allergic to antiseptic agents, previous skin infection at surgical site, refused to participate in study and cannot follow-up. The primary outcome was SSI rate within 30 days after surgery.

Results: A total of 87 subjects (38 in the chlorhexidine in water group and 49 in the povidone iodine group) were enrolled. There are 19 males (50%) and 19 females (50%) in chlorhexidine in water group while there are 19 males (38.8%) and 30 females (61.2%)

in povidone iodine group. The overall rate of SSI was 10.5% in chlorhexidine in water group and 16.3% in povidone iodine group (p-value=0.463).

Conclusion: Preoperative skin preparation with chlorhexidine in water tend to had lower SSI rate compared to povidone iodine, even without statistically significant. Future study with larger sample size may reveal any difference.