Impact on quantitative fit-test results after application of prophylactic hydrocolloid dressing under N95 respirators

Abstract

Objective Discomfort and device-related pressure injury (DRPI) caused by N95 filtering facepiece respirators (FFRs) are common. The use of prophylactic hydrocolloid dressings is one of the strategies that may improve comfort and reduce DRPI. In this study, we investigated the impact of these dressings on N95 respirator fit. Methods We performed a repeat quantitative fit testing through the Respiratory Protection Program on 134 healthcare workers (HCWs), who applied hydrocolloid dressings on the bridge of their nose under the N95 FFRs that they passed the initial fit test but reported discomfort with. Results We found that the fit test pass rates, with the hydrocolloid dressings in place, for the semi-rigid cup style (3MTM 1860), the vertical flat-fold style (BYD), the duckbill style (BSN medical ProShield® and Halyard Fluidshield*), and the three-panel flat-fold style (3MTM Aura) N95 FFRs were 94% (108/115), 85% (44/52), 81% (87/108) and 100% (3/3) respectively. There was a statistically significant reduction in the overall fit factors for both the vertical flat-fold and duckbill type N95 respirators, after the application of hydrocolloid dressings. Conclusions Hydrocolloid dressings are likely to disturb the mask seal for non-rigid style N95 FFRs, in particular, the vertical flat-fold style and the duckbill style N95 FFRs. Given the risk of mask seal disturbance of N95 respirators as shown in this study, we advocate that any HCW requiring the use of prophylactic dressings should undergo repeat quantitative fit testing with the dressing in place prior to using the dressing and mask in combination.

Fit testing and comfort evaluation of prophylactic dressing use for healthcare workers under N95/P2 respirators in one health service district in Australia

“…However, the bestperforming combinations of respirators and dressings were Trident® respirators and dressing higher pass rates with BYD TM respirators and BSN ProShield (85%; 81%) when a hydrocolloid was applied, compared with our study pass rates when silicone foam dressings were applied (Type 1, 26%; Type 2, 30%). In fact, Ng et al's 12 pass rates for all respirators used in our study was higher than ours when a hydrocolloid was applied (81% v. 63.7%). We could not compare our data from the two participants in our study who were fit-tested with a hydrocolloid and who were removed from the analysis because of low numbers.…”

N95 respirators: quantitative fit test pass rates and usability and comfort assessment by health care workers

“…Protective measures, such as a thin hydrocolloid dressing on the bridge of the nose across each cheekbone, might reduce skin injury and improve tolerability, but quantitative fit testing should then be undertaken with this dressing in place. 24 …”

“…Half of the 192 respondents who commented on this feature found the respirator too tight, and almost one‐quarter that it made breathing difficult; 60% reported uncomfortable pressure on the nose and 40% on the cheek. Protective measures, such as a thin hydrocolloid dressing on the bridge of the nose across each cheekbone, might reduce skin injury and improve tolerability, but quantitative fit testing should then be undertaken with this dressing in place 24 …”

Effect of Skin Protectants on the Total Inward Leakage of N95 Respirators: Testing with an Advanced Static Headform

“…The authors reported that the application of this hydrocolloid dressing resulted in the most significant improvement of the respirator fit compared to the other tested skin protectants, which is consistent with our findings. Our data obtained with 3M 1870+ FFR and a hydrocolloid dressing were also compared to the findings of a large human subject study published by Ng et al (2021). Both papers reported a significant improvement in performance of a 3-panel flat-fold style N95 FFR due to the use of a hydrocolloid dressing skin protectant.…”

“…Recent studies have evaluated the effect of skin protectants on the fit factor of respirators/masks worn by human subjects (Guschel et al, 2020;Bergman et al, 2021;Ng et al, 2021;Trehan et al, 2021). However, the findings presented in these reports were affected by the individual (between-subject) variability, which is associated with the differences in breathing patterns, individual face dimensions, and, probably, other factors.…”