A steak from a local grocery store was used to simulate the cutting and electrocautery of a patient. Methodology for Analyzing Environmental Quality Indicatorsĭue to patient privacy issues, ethical considerations and the risks of testing during an actual surgical procedure, the team developed a mock surgical procedure that simulated the steps with a real surgery without the patient. Three sites were chosen to test the hypothesis: a children’s hospital, an adult academic medical center and a general OR at a community hospital.

The hypothesis was that 20 ACH would be cleaner than 15 ACH and 25 ACH would be cleaner than 20 ACH. Given the current codes and practices, the team chose to test the previous Facility Guidelines Institute (FGI) requirements of 15 ACH, the current code of 20 ACH and current practice at many facilities of 25 ACH. To more closely simulate hospital conditions, the team decided that testing the effectiveness of different air-change rates would be accomplished best during a simulated surgical procedure in an existing OR to replicate actual conditions. The quality data then could be compared to the estimated cost of providing these large quantities of filtered, conditioned air to provide a cost-benefit analysis for different air-change rates. Segment of a mock surgical-procedure scriptīased on these published studies, the team felt that research in an actual hospital setting with dynamic operating conditions would be the most accurate method to measure and understand the impact of different air-change rates on air quality in ORs. While there were differing opinions on the percentage of SSIs that could be linked directly to airborne transmission, there was clear consensus that airborne contaminants can cause infections. The team also discovered several studies that linked air quality to SSIs. The National Institutes of Health have completed several good studies that demonstrate room-contamination levels and how they respond to air distribution using computational fluid dynamics. Researching the problemĪs the team completed a literature review on the topic, several studies were found that tested the indoor environment in a static or empty OR or even in a laboratory. The team included a board-certified surgeon, a microbiologist specializing in infection control, an industrial hygienist, a mechanical engineer and an environmental engineer all with health care experience. Do the higher ventilation or air-change rates actually provide a cleaner environment and possibly reduce the risk of surgical-site infections? This is the question that a multidisciplinary group undertook to research at several hospital sites in a study partially funded by the American Society for Healthcare Engineering (ASHE).

Effective airflow vs relative airflow