Air Quality and Employee Hygiene-related Behavior in a Post Anesthesia Care Unit in Thailand

Airborne contaminants in Postanesthesia Care Units (PACUs) such as bacteria, fungi, and waste anesthetic gases pose serious, and sometimes fatal, risks to both patients and PACU workers. Numerous studies have linked long-term exposure to nitrous oxide and halogenated agents to, among other things, reproductive problems in PACU nurses and anesthesiologists. Microorganism contamination can result in a post-surgical complication, to which patients with diabetes and other respiratory diseases are especially vulnerable. Various researchers and governmental agencies have recommended hospitals take steps to reduce levels of airborne contaminants in PACUs. In particular, hazard communication programs are recommended to inform and train staff on relevant occupational health and safety procedures. Additionally, and perhaps more importantly, experts recommend hospitals install specialized ventilation systems to maintain low levels of airborne pollutants.

This study has two main parts: (1) measurement of airborne contaminants in the PACU at Rajavithi Hospital in Bangkok, Thailand; and (2) assessment of PACU workers’ perceived level of importance regarding occupational health and safety protocols, via self-reporting survey. The study also has two main objectives: (1) to determine whether, and to what extent, a new ventilation system helps reduce airborne contaminants in the PACU; and (2) to discover whether an informational campaign increases perceived importance of health and safety procedures among PACU workers (i.e. handwashing, changing shoes, wearing proper facemasks).

Surveys and air quality measurements were collected two times – in July 2016 and April 2017 – before and after Rajavithi Hospital implemented a hazard communication program consisting of training, posters, brochures, and informational media. Survey participants included all 64 PACU workers – 61 nurses and 3 anesthetists. Air sampling measured levels of bacteria, fungi, nitrous oxide, and desflurane.

Initial levels of airborne microorganisms were very high (1307CFU/m³ for bacteria and 70.4 CFU/m³ for fungi) and on the high end of normal for nitrous oxide (21.86ppm). Following the informational campaign and installation of the ventilation system, levels of bacterial contamination fell to 182 CFU/m³, and fungi fell to 35.8 CFU/m³. Simultaneously, workers’ levels of perceived importance for health and safety procedures increased.

Both aspects of the study were successful, however, concentration of airborne microorganisms still exceeded recommended limits at the end of the study. Hospital administration and staff are encouraged to continue training and informing workers while assessing ventilation system until contamination levels fall to within internationally acceptable ranges.