The Effect of Absorbent Pad Design on Skin Wetness, Skin/Pad Microclimate, and Skin Barrier Function: A Quasi-experimental Open Cohort Study.

PURPOSE: The main aims of this study were to describe the effects of incontinence pad composition on skin wetness, the skin/pad microclimate, and skin barrier function. We also evaluated the potential utility of our methods for future clinical investigation of absorbent pad design. DESIGN: Single-blind, quasi-experimental, open cohort design. SUBJECTS AND SETTING: Twenty healthy older volunteers (mean age = 72.8 years, SD = 5.8 years; 8 male and 12 female) tested 2 absorbent pad types, with acquisition layers of different compositions (A and B) applied to different sites on the volar aspect of the forearms. One type A pad served as control (A dry) versus 3 pad samples wetted with 3 volumes of saline (A 15 mL, A 35 mL, and B 15 mL). The study was conducted within the clinical laboratory of a university nursing research group in the United Kingdom. METHODS: Skin barrier function was assessed by measuring transepidermal water loss (TEWL), stratum corneum (SC) hydration by corneometry, and skin surface pH using a standard skin pH electrode. Skin water loading (excess water penetration into the skin) was quantified by measuring TEWL and creating a desorption curve of the water vapor flux density. Calculating the area under the curve of the desorption curve to give skin surface water loss reflected excess water penetration into the skin. In a subgroup of the sample, the temperature and relative humidity (microclimate) at the interface between the skin and test pads were measured using a wafer-thin sensor placed between the skin and pad sample. Proinflammatory cytokine release from the SC was assessed using a noninvasive lipophilic film. The main outcome measures in this study were the differences in biophysical measurements of skin barrier function (TEWL, corneometer, and pH) before and after the application of the different pads. RESULTS: Mean ± SD baseline TEWL across all test sites was 10.4 ± 4.4 g/h/m. This increased to 10.6 ± 3.8 g/h/m at the control site, 15.3 ± 6.3 g/h/m for the A 15-mL pad, 15.3 ± 3.9 g/h/m for the A 35-mL pad, and 15.6 ± 3.2 g/h/m for the B 15-mL pad. The mean baseline skin surface pH was 5.9 ± 0.04; cutaneous pH increased to a mean of 6.1 ± 0.06 following all pad applications (P = .16). Mean SC hydration remained unchanged at the control site (A dry). In contrast, SC hydration increased following the application of all wetted pads. Target cytokines were detected in all samples we analyzed. The IL-1RA/IL-1α ratio increased following pad application, except for the wettest pad. CONCLUSION: Study findings suggest that absorbent pad design and composition, particularly the acquisition layer, affect performance and may influence skin health. Based on our experience with this study, we believe the methods we used provide a simple and objective means to evaluate product performance that could be used to guide the future development of products and applied to clinical settings.

The Impact of Microclimate on Skin Health With Absorbent Incontinence Product Use: An Integrative Review.

This integrative review considers the role of skin occlusion and microclimate in incontinence-associated dermatitis (IAD), with a particular focus on disposable, body-worn, absorbent incontinence products. Although the mechanisms are not fully understood, the primary causes of IAD are well-established: occluded skin, in prolonged contact with urine and/or feces and exposed to abrasive forces, is more likely to be affected, and each of these factors can be influenced by wearing absorbent incontinence products. Studies comparing the effect of various absorbent products on skin health have been hindered by the many differences between compared products, making it difficult to clearly attribute any differences in performance to particular materials or design features. Nevertheless, the large and significant differences that have sometimes been found invite further work. Breathable back sheets can significantly reduce the temperature of occluded skin and the humidity of the adjacent air, and several treatments for nonwoven top sheet materials (used next to the skin) have been shown to impart antimicrobial properties in the laboratory, but an impact on IAD incidence or severity has yet to be demonstrated directly. Recent work to introduce sensing technology into absorbent incontinence products to reduce the exposure of skin to urine and feces, by encouraging prompt product changing, seems likely to yield measurable benefits in terms of reducing incidents of IAD as the technology develops. Published work to date suggests that there is considerable potential for products to be engineered to play a significant role in the reduction of IAD among users.

Method for Bacterial Growth and Ammonia Production and Effect of Inhibitory Substances in Disposable Absorbent Hygiene Products.

PURPOSE: The purpose of this study was to evaluate a pragmatic laboratory method to provide a technique for developing incontinence products better able to reduce malodor when used in the clinical setting. METHODS: Bacterial growth and bacterially formed ammonia in disposable absorbent incontinence products was measured by adding synthetic urine inoculated with bacteria to test samples cut from the crotch area of the product. The inhibitory effect's of low pH (4.5 and 4.9) and 3 antimicrobial substances-chlorhexidine, polyhexamethylene biguanide (PHMB), and thymol-at 2 concentrations each, were studied. RESULTS: From the initial inocula of 3.3 log colony-forming units per milliliter (cfu/mL) at baseline, the bacterial growth of the references increased to 5.0 to 6.0 log cfu/mL at 6 hours for Escherichia coli, Proteus mirabilis, and Enterococcus faecalis. At 12 hours there was a further increase to 7.0 to 8.9 log cfu/mL. Adjusting the pH of the superabsorbent in the incontinence product from 6.0 to pH 4.5 and pH 4.9 significantly (P < .05) inhibited the bacterial growth rates, in most cases, both at 6 and 12 hours. The effect was most pronounced at pH 4.5. Chlorhexidine had significant (P < .05) inhibitory effect on E. coli and E. faecalis, and at 12 hours also on P. mirabilis. For PHMB and thymol the results varied. At 6 hours, the ammonia concentration in the references (pH 6.0) was 200 to 300 ppm and it was 1500 to 1600 ppm at 8 hours. At pH 4.5, no or little ammonia production was measured at 6 and 8 hours. At pH 4.9, there was a significant reduction (P < .01). Chlorhexidine and PHMB exerted a significant (P < .01 or P < .001) inhibitory effect on ammonia production at both concentrations and at 6 and 8 hours. Thymol 0.003% and 0.03% showed inhibitory effect at both 6 hours (P < .01 or P < .001) and at 8 hours (P < .05 or P < .001). CONCLUSION: The method described in this study can be used to compare the ability of various disposable absorbent products to inhibit bacterial growth and ammonia production. This technique, we describe, provides a pragmatic method for assessing the odor-inhibiting capacity of specific incontinence products.

Do panty liners promote vulvovaginal candidiasis or urinary tract infections? A review of the scientific evidence.

Panty liners are used to absorb light menstrual flow, vaginal discharge, or urine leakage, or to maintain a clean, dry feeling. Allegations that panty liners may trap heat and moisture to promote vulvovaginal candidiasis (VVC) or promote colonization by microbes that contribute to urinary tract infections appear to be unfounded. As reviewed herein, measurements of the impact of panty liners on skin temperature and skin surface moisture had no clinically meaningful effect on cell densities of genital microflora. Epidemiological investigations of a potential link to VVC were either negative or were inconclusive because of confounding factors. Although enteric microbes reside on the vulva and perineum, no evidence exists that panty liner use promotes urethral colonization by enteric microbes. Moreover, a series of 13 randomized prospective trials of panty liners or ultra-thin pads demonstrated no clinically significant adverse effects either on the skin or on isolation frequencies or cell densities of representative genital microflora. Post-market surveillance systems suggest a low incidence of complaints. Evidence from vulvar clinic patients reveals no significant contribution of these products to persistent vulvar symptoms. Taken together, the scientific evidence supports the conclusion that panty liners are safe when used as intended and do not promote VVC or urinary tract infections.

Lactobacilli in the female genital tract in relation to other genital microbes and vaginal pH.

BACKGROUND: The relationship between lactobacilli and other microbes and the association with vaginal pH in the female genital tract were examined. The study also included evaluation of the possibility of supplying probiotics to the genital tract by using panty liners impregnated with the probiotic strain Lactobacillus plantarum LB931. METHODS: This was a randomized, placebo-controlled, double-blind, multicenter study involving 191 healthy fertile women. Specified microbes were counted and vaginal pH was measured once a month for five consecutive months. RESULTS: Major individual variations in the genital microflora composition and the vaginal pH were found among the women. The number of lactobacilli was significantly related to vaginal pH (p<0.001) and approximately 70% of the women were permanent carriers of individual lactobacilli strains. Women with high numbers of lactobacilli were less prevalent with Group B streptococci than women with low numbers (p=0.036), and these women had a lower mean vaginal pH. The number of lactobacilli also correlated with the prevalence of yeast. LB931 could be found in 86% of the labial samples and 54% of the vaginal samples. CONCLUSIONS: High numbers of lactobacilli may contribute to a low vaginal pH and seem to have a negative influence on Group B streptococci. LB931 could be transferred from the panty liners to both the vagina and the labial fold.