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Microbial Load in Septic and Aseptic Procedure Rooms
Julian-Camill Harnoss1, Ojan Assadian, Markus Karl Diener
1Department of General, Visceral and Transplantation Surgery and Study Center of the German Surgical Society (SDGC), University of Heidelberg; Division for Hospital Hygiene, Vienna General Hospital, Medical University Vienna; Institute for Hygiene and Environmental Medicine, University of Greifswald; Institute of Hospital Hygiene und Infection Prevention, Klinikum Konstanz; Institute for Community Medicine, University of Greifswald; Clinic and Outpatient Clinic for Surgery-Department of General Surgery, Visceral, Thoracic and Vascular Surgery, University of Greifswald.
Background:
Highly effective measures to prevent surgical wound infections have been established over the last two decades. We studied whether the strict separation of septic and aseptic procedure rooms is still necessary.
Methods:
In an exploratory, prospective observational study, the microbial concentration in an operating room without a room ventilating system (RVS) was analyzed during 16 septic and 14 aseptic operations with the aid of an air sampler (50 cm and 1 m from the operative field) and sedimentation plates (1 m from the operative field, and contact culture on the walls). The means and standard deviations of the microbial loads were compared with the aid of GEE models (generalized estimation equations).
Results:
In the comparison of septic and aseptic operations, no relevant differences were found with respect to the overall microbial concentration in the room air (401.7 ± 176.3 versus 388.2 ± 178.3 CFU/m3; p = 0.692 [CFU, colony-forming units]) or sedimentation 1 m from the operative field (45.3 ± 22.0 versus 48.7 ± 18.5 CFU/m2/min; p = 0.603) and on the walls (35.7 ± 43.7 versus 29.0 ± 49.4 CFU/m2/min; p = 0.685). The only relevant differences between the microbial spectra associated with the two types of procedure were a small amount of sedimentation of Escherichia coli and Enterococcus faecalis in septic operations, and of staphylococcus aureus and pseudomonas stutzeri in aseptic operations, up to 30 minutes after the end of the procedure.
Conclusion:
These data do not suggest that septic and aseptic procedure rooms need to be separated. In interpreting the findings, one should recall that the study was not planned as an equivalence or non-inferiority study. Wherever patient safety is concerned, high-level safety concepts should only be demoted to lower levels if new and convincing evidence becomes available.
Insights
This study found no significant difference in microbial contamination between septic and aseptic operating rooms, suggesting separation may not be necessary. Further research is needed to confirm these findings for patient safety.
Area of Science:
- Infection Control
- Microbiology
- Surgical Safety
Background:
- Established infection control measures have significantly reduced surgical wound infections over the past two decades.
- The necessity of strictly separating septic and aseptic procedure rooms is questioned in light of advancements.
Purpose of the Study:
- To investigate whether the strict separation of septic and aseptic procedure rooms remains a necessary practice.
- To compare microbial concentrations in operating rooms during septic versus aseptic procedures.
Main Methods:
- An exploratory, prospective observational study was conducted in an operating room without a room ventilating system (RVS).
- Microbial concentration was analyzed using an air sampler and sedimentation plates during 16 septic and 14 aseptic operations.
- Generalized estimation equations (GEE) models were used to compare microbial loads.
Main Results:
- No relevant differences in overall microbial concentration were observed in room air (p = 0.692), sedimentation 1m from the operative field (p = 0.603), or on walls (p = 0.685) between septic and aseptic operations.
- Minor differences in microbial spectra were noted, with specific bacteria like E. coli and E. faecalis found in septic cases, and S. aureus and P. stutzeri in aseptic cases.
- These differences in microbial spectra were observed up to 30 minutes post-procedure.
Conclusions:
- The study's data do not indicate a need for separate septic and aseptic procedure rooms.
- It is crucial to acknowledge that this study was not designed as an equivalence or non-inferiority trial.
- High-level patient safety protocols should only be downgraded with new, compelling evidence.
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