Controlled Substance Liquid Waste Management Systems As Potential Reservoirs for Nosocomial Infection in a Pediatric Hospital.

Objective: The purpose of this study was to determine if controlled substance waste management systems (CSWMS) demonstrate microbial growth, and therefore present a potential infection risk to pediatric hospital patients.

Methods: Twenty CSWMS, either Smart Sink or Pharma Lock systems, located in patient care areas were sampled. Twelve were located in critical care areas. Cultures were obtained by swabbing the drain grate with a sterile swab. Swabs were then transported to the microbiology lab for culture. Each sample was labeled with the location of the CSWMS and each system was photographed.

Results: Of the CSWMS sampled, 50% demonstrated bacterial or fungal growth with a total of 15 microorganisms isolated, including 3 systems with Micrococcus luteus, 2 with Aspergillus species, and 2 with -Bacillus cereus. Nine of the 15 microorganisms isolated were from systems in the pediatric intensive care unit (PICU) followed by 2 microorganisms in the neonatal intensive care unit (NICU). Of the 12 systems sampled in critical care areas, 8 (66%) had positive cultures. Of the 10 systems which demonstrated growth, 9 were Pharma Lock and 1 was Smart Sink.

Conclusion: Controlled substance waste management systems harbor potential pathogens and may serve as reservoirs of infectious agents in pediatric hospitals. Microbial growth was identified in more than half of sampled CSWMS located in critical care areas, where the most vulnerable patients are located. Based on this study, a cleaning procedure for CSWMS should be implemented. Further investigation on the relationship between CSWMS and nosocomial infections is warranted.