Impact of operating room personnel density on aerobiome-related infection risk in penile implant surgery

BACKGROUND: Erectile dysfunction refractory to medical therapy is most effectively treated with inflatable penile prosthesis (IPP) implantation, yet infection remains the principal complication. Operating room traffic and airborne exposure have long been suspected contributors, though their impact on prosthetic urology remains unexamined. AIM: To evaluate whether operating room personnel density, as a surrogate for aerobiome burden, contributes to microbial colonization of IPPs under sterile surgical conditions. METHODS: An ex vivo experimental study was conducted using Rigicon® Infla10X IPP without antibiotic coating. The device was exposed for 45 min to 4 real-world operating room scenarios with varying personnel densities: 4 (standard surgery), 8 (dual-surgeon team), 16 (educational surgery), and 32 (masterclass). The IPP was swabbed at reservoir, pump, and cylinders. Samples underwent DNA extraction, full-length 16S rRNA sequencing (Oxford Nanopore Technologies, Oxford, UK), and quantitative polymerase chain reaction (qPCR). Positive controls (Escherichia coli ATCC 25992) were included. OUTCOMES: The primary outcome was microbial colonization of IPPs, defined as detectable microbial DNA by sequencing or qPCR across personnel-density groups. RESULTS: No microbial DNA was detected in any of the 12 swabbed IPP samples across all groups, whereas the positive controls amplified successfully, confirming methodological validity. Personnel density did not influence microbial colonization, with uniformly negative results in 4-, 8-, 16-, and 32-staff conditions. CLINICAL IMPLICATIONS: This study demonstrated that operating room personnel density was not associated with increased microbial colonization of IPP via airborne exposure. The results support the safety of educational and live-surgery settings with larger teams when strict sterility protocols are followed. STRENGTHS AND LIMITATIONS: Strengths include a controlled ex vivo design, simulation of real-world surgical conditions, and comprehensive microbial assessment using next-generation sequencing with qPCR. Limitations include the ex vivo nature of the study, evaluation of a single IPP model without antibiotic coating, and limited exposure duration of 3 hours. CONCLUSION: Operating room personnel density did not influence microbial colonization of IPPs under sterile conditions. Airborne exposure may not be a primary factor in the pathogenesis of IPP infection, underscoring the importance of alternative contributors, such as skin-to-implant contact. Further ex vivo and in vivo studies are warranted to clarify infection mechanisms.