Previous studies have compared laminar airflow with conventional ventilation, ignoring many parameters influencing airflow properties.

The present study assessed the impact of operating room (OR) ventilation quality on surgical site infections (SSIs) using a novel ventilation index.

It surveyed hospitals participating in the Swiss SSI surveillance and calculated a ventilation index for their ORs, with higher values reflecting less turbulent air displacement. For procedures captured, it studied the association between ventilation index and SSI rates using linear regression (hospital-level analysis) and the individual SSI risk using generalized linear mixed-effects models (patient-level analysis).

The study observed-

• Enrolment of 47 hospitals (182 ORs).
• Among the 163,740 included procedures, there were 6791 SSIs.
• In hospital-level analyses, a 5-unit increase in the ventilation index showed an association with lower SSI rates for knee and hip arthroplasty and cardiac and spine surgeries.
• In Patient-level analyses, a lower SSI risk was present with each 5-unit increase in ventilation index.
• Higher index values showed an association with a lower risk for superficial and deep incisional SSIs.

This study shows that better ventilation properties, assessed with this ventilation index, cause lower rates of superficial and deep incisional SSIs in orthopedic and cardiac procedures. OR ventilation quality may be less relevant for other surgery types.

Source:  Epub 2022 Aug 10. PMID: 35946824; PMCID: PMC9534050.