Written by Megan Hilbert
Spoon Feed
Povidone iodine was shown to be noninferior to chlorhexidine gluconate in the preparation of intact pre-operative skin and prevention of surgical site infections (SSIs).
Cutting through the [bacterio]static
This was a multi-center, cluster-randomized, investigator-masked, crossover noninferiority trial to evaluate whether povidone iodine in alcohol is noninferior to chlorhexidine gluconate in alcohol in preoperative skin preparation. Primary outcome was incidence of SSIs within 30 days of abdominal surgery and within 1 year of cardiac surgery – prolonged due to presence of sternal wires. Secondary outcomes evaluated included evaluating the infection by depth as well as by type of surgery. They found an infection rate of 5.1% in the iodine group and a 5.5% infection rate in the chlorhexidine group. This difference of 0.4% (95%CI -1.1% to 2.0%) did not meet the noninferiority margin of 2.5% that was set by the investigators and held even when data was clustered.
Why could this be important? There is evidence that there is decreased susceptibility/emerging resistance to chlorhexidine. Chlorhexidine also tends to be more expensive than other available products. Having said that, iodine-based products can differ in their amount of free iodine which could affect its bacteriostatic properties.
Ultimately what remains most important is a standardized cleaning process with an exposure time of at least 3 minutes (regardless of the product that is being used). There also likely exists a baseline difference in post-operative infection incidence depending upon the type of surgery.
How will this change my practice?
In the ED I tend to reach for chlorhexidine when prepping an area prior to a procedure. I would be curious to see if they could complete a similar evaluation on non-intact skin (as is typically seen in the ED) and if the results would continue to demonstrate noninferiority among the two products.
Source
Povidone Iodine vs Chlorhexidine Gluconate in Alcohol for Preoperative Skin Antisepsis: A Randomized Clinical Trial. JAMA. 2024 Jun 17:e248531. doi: 10.1001/jama.2024.8531. Epub ahead of print. PMID: 38884982; PMCID: PMC11184497.
