Enhanced Intraoperative Hygiene Reduces C. Acnes Contamination in Cardiac Surgery: JAMA

This study involved male patients undergoing cardiac surgery for the first time, performing their observation activities from October 28, 2024, till March 3, 2025, and completing all data analyses by the beginning of 2026. For complete data integrity, neither the patients nor the laboratory technicians who conducted the microbiological analyses knew about the groups to which the participants belonged. A per-protocol analysis was chosen as the one used in the final assessment of the experiment. Six patients were eliminated after randomization because of the mistakes made during the implementation of the intervention procedure.

The participants of the control group underwent the conventional treatment without receiving any additional interventions, meaning that they needed to undergo the outer glove change immediately after the completion of the sternotomy and nothing else. However, the patients in the intervention group got three additional procedures performed immediately after the completion of the sternotomy, the outer glove change, sternal wound margin disinfection with iodine, and sternal wound margin isolation with sterile absorption pads.

Key findings:

• The randomized interventional analysis effectively analyzed perioperative data from the key cohort of 124 males divided equally between the intervention group and control group.
• It is important that cutibacterium acnes was found significantly less often in the intervention group patients, where there were only 9 people (14.5%) out of 62 people, compared to 38 people (61.3%) out of 62 people in the control group.
• Such differences led to the impressive risk ratio of 0.24 (95% CI, 0.13 to 0.45; P < .001), which means the relative risk reduction equal to 76%.
• As far as the intensity of bacteria growth in the deep pericardium, it was 100% negative or light thioglycolate-only growth in the intervention group while 43.5% (27 patients) had heavy agar growth from 1+ to 3+ in the control group.
• Bacterial contamination overall was also lower – 16.1% (10 out of 62 people) compared to 71% (44 out of 62 people) in the control group with the risk ratio of 0.23 (95% CI, 0.13 to 0.41; P < .001).
• Statistical modeling showed that the high chest hair density is a significant independent risk factor for bacterial transfer (odds ratio of 1.16 (95% CI, 1.02 to 1.31; P = .02)).

In conclusion, during this randomized study among 124 male subjects undergoing cardiac surgery, there was a reduction in C acnes transmission to the wound site through the introduction of further hygienic interventions around the wound margin. This relatively inexpensive approach should be adopted in standard surgical procedures to help avoid endocarditis due to prosthetic valves. These empirical statistics from the prospective surveillance have proved to be invaluable to hospital epidemiology because small changes to aseptic procedure could prevent deep anatomic bacterial pathway transmission.

Reference:

Moter I, Schubert S, Goncalves A, et al. Prevention of Surgical Site Contamination With Cutibacterium acnes During Cardiac Surgery: A Randomized Clinical Trial. JAMA Netw Open. 2026;9(7):e2621857. doi:10.1001/jamanetworkopen.2026.21857