Operating room environmental improvements with Venturi valves and Environmental Quality Indicator risk prediction may help reduce Surgical Site Infections

Main Article Content

Jennifer A. Wagner, Ph.D Greeley Damon G., PE, CEM, HFDP, CBCP, EDAC, CHFM Sieber Marnie S., MSN, RN


Introduction: There is mounting evidence supporting the connection of the operating room airborne environment to Surgical Site Infections (SSI). Environmental Quality Indicators (EQI) can be measured to determine the risk of microbial contamination in the OR by room sector. This risk picture is used to inform educated improvements to the aseptic environment. When improvements based on the EQI risk picture are combined with precise control of the airborne environment using Venturi technology, the asepsis of the OR is maintained and the risk of contamination is lower. This study sought to determine if precisely maintained asepsis in the OR based on EQI risk picture lowered the SSI rate.

Methods: The environmental quality indicators in a Craniotomy OR were measured and a risk picture, by room sector, was created. The EQIs measured included air change rates, humidity, temperature, pressure, particle counts, occupancy, traffic patterns, air flow and directionality, and door openings, among others. Improvements to the OR performance were made based on the risk picture and Venturi technology was used to precisely control the airborne environment. SSIs were tracked for 17 months prior to improvements and then for 10 months following the improvements.

Results: The asepsis of the OR airborne environment was improved and an EQI risk picture was developed following improvements to document improvement. In the 17 months prior to improvements to the OR, there were 14 SSIs out of 430 total surgeries and the SSI rate was 3.9%. In the 10 months following the improvements, there was 1 SSI out of 180 surgeries, and the SSI rate was 0.5%. The reduction in SSIs was statistically significant at p=.0377 following improvements.

Conclusion: Improvement of the airborne environment in ORs improves the asepsis and may help reduce SSI.

Keywords: Surgical Site Infection, Environment, Environmental Quality Indicators, Risk Assessment

Article Details

How to Cite
WAGNER, Jennifer A.; G., Greeley Damon; S., Sieber Marnie. Operating room environmental improvements with Venturi valves and Environmental Quality Indicator risk prediction may help reduce Surgical Site Infections. Medical Research Archives, [S.l.], v. 11, n. 1, jan. 2023. ISSN 2375-1924. Available at: <https://esmed.org/MRA/mra/article/view/3475>. Date accessed: 02 apr. 2023. doi: https://doi.org/10.18103/mra.v11i1.3475.
Research Articles


1. Birgand G, Toupet G, Rukly S, et al. Air contamination for predicting wound contamination in clean surgery: a large multicenter study.
Am J Infect Control. 2015;43(5):516-521.

2. Howorth FH. Prevention of airborne infection during surgery. Lancet.1985;1(8425):386-388.

3. Lidwell OM, Lowbury EJ, Whyte W, et al. Effect of ultraclean air in operating rooms on deep sepsis in the joint after total hip or knee replacement: a randomized study.Br Med J. 1982;285(6334):10-14

4. Analyzing ICU Patient Room Environmental Quality Through Unoccupied, Normal, and Emergency Procedure Modes: An EQI Evaluation. Wagner, J., Gormley, T., Greeley, D. and Markel, T. HERD. June 2019.
DOI: 10.1177/1937586719854218

5. Pressure | Honeywell Technologies. Honeywell building technologies. Retrieved from https://buildings.honeywell.com/us/en/solutions/healthy-buildings/pressure on January 19, 2022.

6. Operating Room Improvements Based on Risk Prediction Can Help Reduce SSIs: Three Case Studies. Wagner J, Greeley D. AORN J. 2020 Nov;112(5):551. doi: 10.1002/aorn.13224. PMID: 33113181.

7. Wagner, J., Gormley, T., Markel, T., & Greeley, D. (2022). Operating Room Improvements Based on Environmental Quality Index Risk Prediction can help Reduce Surgical Site Infections. Medical Research Archives, 10(10). doi:10.18103/mra.v10i10.3179

8. Memarzadeh F, Weiren XU. Role of Air Changes per hour (ACH) in possible transmission of airborne infections. Build Simul.2012;5:15

9. ASHRAE. Ventilation of healthcare facilities. (Standard 170-2013). 2013