Bryan Connors to Speak at 2022 APIC Annual Conference, June 13-15

Air Tracing to Identify Hospital Infection Risk Pathways

Bryan Connors, M.S., C.I.H., HEM
Managing Principal Consultant, Healthcare

Bryan Connors will present a novel approach of applying the “source-pathway-receptor” model by air tracing to identify exposure pathways during investigations of hospital acquired infections. Infection preventionists must have a strong understanding of best tools available to prevent and investigate infections related to the physical environment. Tracer particle and gas studies offer a proven approach to trace the airflow pathway between spaces. Three demonstrative case studies are presented:

  1. A COVID-19 outbreak among hospital’s staff and patients was theorized to be associated with release of viral particles generated during “aerosol generating procedures” (AGP). A tracer gas study was conducted to determine air pathways; we found 30% to 60% of the aerosols could be directly transmitted to the nearby nursing station from the positive pressure room where APGs were conducted.
  2. Three patients were identified with surgical site infections secondary to Mycobacterium abscessus (M. abscessus). The patients had undergone cardiac surgery in the same operating room (OR) during which modular cooler-heaters (MCHs) were used, and mycobacterium was also isolated from water samples. A tracer particle study was conducted to evaluate the pathway of exposure to M. abscessus from the MCHs. The study found particle transfer directly from the MCH to the sterile field.
  3. Multiple ORs were shut down due to increased surgical site infection rates in one OR. A particle measurement study evaluated the effectiveness of the ventilation system at preventing particles from impacting the wound site. Results showed that the ventilation system for the affected OR was less effective in maintaining a sterile field. This was found to be associated with the loss in downflow velocity due to variations in the air temperature supplied by the ventilation system. As a result, modifications to the control sequence in the affected OR were made and then validated by a second particle study.

APIC 2022 Annual Conference

June 13-15, 2022
Indianapolis, IN
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