The general decolonization of the human body surface by industrial antiseptic agents, before elective surgery is recommended by the World Health Organization (WHO).

A specific randomized-controlled trial specifically among high-risk adult orthopedic patients for infection has not been performed.

In this single-center, prospective, randomized, and controlled superiority trial, which is planned over a period of two years, we target on an orthopedic patient population with an elevated risk for revision surgery and surgical site infections

The general decolonization of the human body surface and, of adjacent pathogen reservoirs such as the nose, by industrial antiseptic agents by the World Health Organization (WHO) for the risk reduction of superficial and deep surgical site infection (SSI). Such a decolonization is regarded as evidence-based in the majority of randomized, and before-after trials, since two decades, although negative studies also exist.

In the orthopedic field, this decolonization is likely to be more effective in elective patients with a proven body colonization of Staphylococcus aureus. The decolonization might be equally efeective in orthopedic patients with an inherent high risk for SSI, for which the majority of future SSI pathogens are skin commensals and S. aureus. These (eventual and future) pathogens of SSI are accessible to the topical agents during the index surgery, if the patients are well instructed and know how to decolonize themselves.

In contrast, this pre-surgical decolonization is only a supplementary measure in the bundle of all combined efforts to prevent revision surgery for infection. Its individual power is limited for young, healthy individuals, for SSIs caused by pathogens from the internal body sites (intestinal, urinary, gynecologic regions), infections acquired on the surgical ward, and in settings with less specialized surgeries and a low volume of surgical experience. Hence, in trials including all patients (or only those carrying S. aureus), the beneficial effect of decolonization can be diluted and provoke an additional costly and cumber-some organizational procedure for the majority of patients with low to moderate SSI risks.

Moreover, many surgical site infections in orthopedic surgery, especially in implant-related surgery, are more due to coagulase-negative staphylococci (CoNS) than for S. aureus.

The hallmark of the CoNS group is S. epidermidis with approximatively 70% resistance (in Switzerland) to standard prophylactic antibiotic agents9, As S. epidermidis is part of the normal human flora, typically the skin flora, and, only becomes pathogenic under certain conditions, a screening for this microorganism is not feasible in common practice,. while the prophylaxis-resistant part of all orthopedic SSI pathogens is at 30-50%.

In this single-center, prospective, randomized, and controlled superiority trial, which is planned over a period of two years, we target on an orthopedic patient population with an elevated risk for revision sur-gery and SSI; inde-pendently of a known body carriage for S. aureus.

This study will be performed with an existing "set" manufactured by Schülke & Mayr GmbH. The "Set" was placed on the market in 2016. The distribution of Octenisan® wash lotion and Octenisan® nasal gel in the form of a set (Octenisan® Set) largely streamlines and facilitates the organizational application and compliance efforts of the study.

Academically and clinically, we will gain insight in the performance of decolonization for a patient population at particular risk of postoperative complications, where every effort to prevent infection is of importance.

Inclusion Criteria:

• Age ≥ 18 years
• Patients with an age ≥ 80 years (as considered particularly at risk for SSI)
• Elective orthopedic surgery at the Balgrist
• Chronic immune-suppression (diabetes mellitus, active cancer, cirrhosis CHILD C, renal dialysis, untreated HIV disease, medicamentous immune-suppression equivalent to prednisone ≥ 10 mg/day)
• Elective surgery in ischemic skin (e.g. major amputations)
• Elective surgery on non-diabetic and non-infected ulcerated skin
• Tumor (oncologic) orthopedic surgery
• ASA-Scores 3-4 points

Exclusion Criteria:

• Elective revision orthopedic surgery due to orthopedic infection within the last 12 months in the same area of surgery
• Emergency surgery (defined as planned surgery within the next 48 hours)
• Surgery on infected skin; or surgery under antibiotic treatment for any reason
• "Diabetic foot surgery" (distinct clinical entity; defined as below the ankle)
• Body mass index ≥ 35 kg/m2 (anticipated difficulty of effective decolonization)
• Pregnancy (formality reasons)
• Intolerance or allergy to octenidin and/or ingredients in the Octenisan® set
• Use of any other topical antiseptic agents other than Octenisan® set (except for the duration of one day)
• Patient unable to understand; or under legal guardian for medical decisions
• Anticipated clinical follow-up of less than 6 weeks after surgery.
• ASA-Scores 1-2, and ASA-Score 5 (high risk of postoperative complications)
• Known skin colonization with antibiotic-multiresistant Gram-negative organisms defined by infection control protocols of Switzerland1

The Study Protocol will be published separately The results of the study will be a publication

Before and after the study (February 2023 and May 2025)

Will be published in PubMed