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A bstract Aim and objective Fogging of eyeglasses while wearing N95 respirators is common. It is commonly held that the N95 respirator has a poor fit if there is fogging of eyeglasses. We conducted this prospective, pilot study to determine if fogging of eyeglasses predicts poor fit of N95 respirator. Materials and methods Seventy volunteer healthcare workers from a tertiary intensive care unit in Sydney, Australia participated. The participants donned one of the following N95 respirators: three-panel flat-fold respirator (3M 1870), cup-shaped respirator (3M 1860), or a duckbill respirator. After a satisfactory “user seal check” as recommended by the manufacturer, the participants donned eyeglasses and checked for fogging. A quantitative fit test (QnFT) of the respirator was then performed (using PortaCount Respirator Fit Tester 8048, TSI Inc., Minnesota, USA). A fit factor of <100 on quantitative fit testing indicates poor fit. The sensitivity and specificity for fogging of eyeglasses (index test) to predict the poor fit of N95 respirator was determined, compared to QnFT (gold standard test). Results Fogging of eyeglasses as a predictor of poor respirator fit (i.e., fit factor <100 on QnFT) had sensitivity of 71% (95% CI, 54–85%) and specificity 46% (95% CI, 29–63%). The odds ratio of fogging as a predictor for poor fit was 2.10 (95% CI, 0.78–5.67), with a two-tailed p -value of 0.22 (not significant). The receiver operating characteristic curve for fogging of eyeglasses as a diagnostic test had the area under the curve of 0.59. Conclusion Fogging of eyeglasses is neither a sensitive nor a specific predictor for poor fit of N95 respirators. How to cite this article Kyaw S, Johns M, Lim R, Stewart WC, Rojas N, Thambiraj SR, et al. Prediction of N95 Respirator Fit from Fogging of Eyeglasses: A Pilot Study. Indian J Crit Care Med 2021;25(9):976–980.

Lupin is a major rotational crop produced abundantly in Australia. Three varieties of sweet lupins are grown in Australia depending on soil types and climatic conditions; these are white lupin (Lupinus albus), blue lupin (Lupinus angustifolius), and yellow lupin (Lupinus luteus). In this study, polysaccharides from the three lupin species have been extracted with hot water and a range of their biological activities investigated. The antioxidant activities of lupin polysaccharides have been measured in terms of ABTS •+ radical and hydroxyl radical scavenging activities, and their affinity to chelate with iron. Immuneenhancing power of the lupin polysaccharides was examined by measuring their capacity to stimulate the macrophages (RAW 264.7) to release TNF-α and nitric oxide. The prebiotic activities were determined against the beneficial probiotics such as Lactobacillus rhamnosus DR20, Lactobacillus acidophilus LAFTI L10, Bifidobacterium lactis DR10, and Bifidobacterium animalis BB-12. Polysaccharides from the three lupin species have exhibited significant antioxidant, immunostimulatory, and prebiotic activities. The results demonstrated that blue lupins displayed the best activities, and therefore are expected to possess high potential to be used as nutraceutical and functional ingredients with significant therapeutic value. FT-IR spectroscopic technique was employed for a preliminary structural characterization. Studies involving surface morphology and thermal behavior have indicated that the lupin polysaccharides are suitable for end product development.

A bstract N95 respirators and safety goggles are important components of personal protective equipment to reduce the spread of airborne infections, such as COVID-19, among healthcare workers. Poor N95 respirator seal may reduce its protective effect, thereby increasing transmission. Quantitative fit testing is an established way of assessing the N95 respirator fit, which provides a quantitative measure for seal, called the fit factor. Duckbill N95 respirators frequently fail the fit test. We hypothesized that using safety goggles with a wraparound elastic headband will increase their fit-factor by reinforcing the seal between the face and the upper margin of the respirator. We studied the effect of safety goggles with a wraparound elastic headband (3M™ Chemical Splash Resistant Goggles, ID 70006982741) on the fit factor of two types of Duckbill N95 respirators (Halyard FLUIDSHIELD*3, Model 99SA070M, and ProShield® N95 Model TN01-11) in 63 healthy volunteers in a nonrandomized, before-and-after intervention study design. The mean fit factor increased from 69.4 to 169.1 increased from 17/63 (27%) to 46/63 (73%) after the intervention ( p <0.0001, OR 3 [95% CI = 4.9–1223]). This is the first study to explore the impact of safety goggles on N95 respirator fit. We conclude that the use of safety goggles with a wraparound elastic headband increases the fit factor of the tested Duckbill N95 respirators. How to cite this article Johns M, Kyaw S, Lim R, Stewart WC, Thambiraj SR, Shehabi Y, et al . Fit Factor Change on Quantitative Fit Testing of Duckbill N95 Respirators with the Use of Safety Goggles. Indian J Crit Care Med 2021;25(9):981–986.