Update on Personal Protective Equipment
By Amesh A. Adalja, M.D., December 19, 2008
In virtually all pandemic plans, the use of personal protective equipment (PPE) is a key component of protection for healthcare workers (HCWs) and prevention of disease spread. Two recent studies raise important questions about the best use of PPE by healthcare workers and should prompt further study and examination of current recommendations, policies, and readiness.
N-95 Respirator Fit Testing: Is It Worth the Time and Effort?
Current guidelines from the U.S. Department of Health and Human Services (HHS) recommend that use of N-95 respirators is prudent in all direct patient care activities during an influenza pandemic. Additionally, any situation requiring airborne isolation procedures (e.g., pulmonary tuberculosis) also merits use of an N-95 mask. Hospitals arrange fit testing at regular intervals to ensure that appropriately sized masks are deployed and used correctly. However, fit testing is an exercise that can be cumbersome and logistically challenging.1
Results of Canadian Study Suggest that Practice is More Important than Fit Testing
Researchers from the University of Alberta recruited 58 HCWs to test the efficacy of N-95 respirator fit testing; none of the subjects had been fit tested before.1 The purpose of the study was to answer the following questions: 1) Can an acceptable seal be achieved without prior training or testing? 2) Does training ensure an acceptable seal during future use? 3) Does regular use of a respirator improve consistency in achieving a seal?
Of the 58 HCWs who attempted to use a respirator without fit testing, training, or instruction, 48% achieved an adequate seal—all with the same size standard 3M 8210 N95 respirator. After this portion of the study was complete, formal training was provided, and an additional 30% of workers passed. In all, 74.4% of workers achieved an adequate seal with the 8210 respirator. Of the participants for whom the 8210 was not adequate, 23.3% required a smaller model, while 2.3% required a larger model.
Participants were then recalled at 3 and 14 months after the initial exercises, and significant failure rates were observed at both intervals, suggesting the need for continued use of the masks for competency in deployment. This is supported by the finding that the skills of nurses on a respiratory ward, where airborne isolation precautions are more common, were not severely compromised over time.1
In their discussion of the study, the authors note that 48% of HCWs will be sufficiently protected with the deployment of 8210 respirators, without training, and that instruction alone will increase the rate to 74.4%. They suggest that the only benefit of fit testing is the identification of those “individuals whose facial features preclude the use of the most common types of respirators.”1 Also highlighted is that HCWs’ ability to retain their skills in N-95 mask use is diminished in those who do not use the respirator regularly. Despite the small size of this study, these findings challenge the current policies regarding the necessity of fit testing and also suggest that re-education may be needed to ensure proper use.1
100% Compliance with Infection Control PPE Measures: At What Cost?
Another study on a similar topic was recently published online by the Journal of Hospital Infection. In this study, a team of UK researchers conducted a simulation exercise utilizing full PPE as would be required during an influenza pandemic. The setting was a 29-bed ward, with 14 nurses, 5 healthcare assistants, and 4 domestic staff, all of whom were required to wear PPE, including gloves, gowns, plastic aprons, masks, respirators, and eye protection, in accordance with national guidance. The results of the 24-hour exercise revealed that during a pandemic, a similar ward could expect to use 5,250 aprons per week (13-fold increase from baseline), 8,400 pairs of gloves (10-fold increase from baseline), 4,450 surgical masks (450-fold increase from baseline), and 90-100 respirators. Additionally, there was a 3-fold increase above baseline in the amount of waste generated.2
In their discussion, the authors highlight the financial and logistical burden that full PPE deployment places on hospitals in terms of costs, supply stocks, and waste. Certain equipment, such as the respirators, has a shelf-life and must be replaced to ensure full efficacy.2
PPE: A Core Component of Pandemic Planning
Taken together, these two papers illustrate the difficulties that healthcare facilities may face during an influenza pandemic when fit testing may not be possible at all. However, as the results of these studies suggest, even without fit testing, at least 50% of HCWs will be able to don an N-95 mask without difficulty. This figure is substantially higher than that on which current fit testing recommendations are based. That said, proper use requires continuous reinforcement for effective PPE deployment, and fit testing does not serve that purpose.
The other important finding of these studies is that use of PPE materials during a pandemic is likely to be much greater than previously thought, and the inventory management systems of modern healthcare facilities may not provide sufficient stock to meet the surging demand. While not the most headline-grabbing aspects of biosecurity, hospital preparedness and HCW PPE are vital to halting the spread of disease and must be addressed by healthcare facilities in their pandemic planning activities.
Lee MC, Takaya S, Long R, et al. Respirator-fit testing: does it ensure the protection of healthcare workers against respirable particles carrying pathogens. Infect Control Hosp Epidemiol. 2008; 29:1149-56.
Phin NF, Rylands AJ, Allan J, et al. Personal protective equipment in an influenza pandemic: a UK simulation exercise. J Hosp Infect. 2008; doi: 10.1016/j.jhin.2008.09.005.
New on the Center's website: Preventing and Deterring Biological Attacks: Priorities that Should Emerge From the WMD Commission Report, a memo from the Center for Biosecurity in response to the WMD Commission Report, World At Risk.