Absorbent products for urinary/faecal incontinence: a comparative evaluation of key product designs.

OBJECTIVES: To compare the performance and cost-effectiveness of the key absorbent product designs to provide a more solid basis for guiding selection and purchase. Also to carry out the first stage in the development of a quality of life (QoL) instrument for measuring the impact of absorbent product use on users' lives. DESIGN: Three clinical trials focused on the three biggest market sectors. Each trial had a similar crossover design in which each participant tested all products within their group in random order. SETTING, PARTICIPANTS AND INTERVENTIONS: In Trial 1, 85 women with light urinary incontinence living in the community tested three products from each of the four design categories available (total of 12 test products): disposable inserts (pads); menstrual pads; washable pants with integral pad; and washable inserts. In Trial 2a, 85 moderate/heavily incontinent adults (urinary or urinary/faecal) living in the community (49 men and 36 women) tested three (or two) products from each of the five design categories available (total of 14 test products): disposable inserts (with mesh pants); disposable diapers (nappies); disposable pull-ups (similar to toddlers' trainer pants); disposable T-shaped diapers (nappies with waist-band); and washable diapers. All products were provided in a daytime and a (mostly more absorbent) night-time variant. In these first two trials, the test products were selected on the basis of data from pilot studies. In Trial 2b, 100 moderate/heavily incontinent adults (urinary or urinary/faecal) living in 10 nursing homes (27 men and 73 women) evaluated one product from each of the four disposable design categories from Trial 2a. Products were selected on the basis of product performance in Trial 2a and, again, day time and night-time variants were provided. The first phase of developing a QoL tool for measuring the impact of using different pad designs was carried out by interviewing participants from Trials 1 and 2a. MAIN OUTCOME MEASURES: Product performance (e.g. comfort, discreetness) was characterised using a weekly validated questionnaire. A daily pad change and leakage diary was used to record severity of leakage, numbers of laundry items and pads. Skin health changes were recorded weekly. At a final interview preferences were ranked, acceptability of each design recorded, and overall opinion marked on a visual analogue scale (VAS) of 0-100 points. This VAS score was used to estimate cost-effectiveness. In addition, a timed pad changing exercise was conducted with 10 women from Trial 2b to determine any differences between product designs. RESULTS: Disposable inserts are currently the mainstay of management for lightly incontinent women (Trial 1) and they were better for leakage and other variables (but not discreetness) and better overall than the other three designs. However, some women preferred menstrual pads (6/85) or washable pants (13/85), both of which are cheaper to use. Washable inserts were worse both overall and for leakage than the other three designs (72/85 found them unacceptable). For disposable inserts and disposable diapers, findings from the community (Trial 2a) and nursing home trials (Trial 2b) were broadly similar. Leakage performance of disposable inserts was worse than that of the other designs for day and night. Pull-ups were preferred over inserts for the daytime. The new T-shaped diaper was not better overall than the traditional disposable one. However, there were important differences in performance and preference findings for men and women from both trials. Pull-ups (the most expensive) were better overall than the other designs for women during the day and for community-dwelling women during the night. Although disposable diapers were better for leakage than disposable inserts (the cheapest), women did not prefer them (except in nursing homes at night), but for men the diapers were better both overall and for leakage and were the most cost-effective design. No firm conclusions could be drawn about the performance of designs for faecal incontinence. Nursing home carers found pull-ups and inserts easier to apply (in the standing position) and quicker (in the pad change experiment) than the diaper designs; the ability to stand was associated with preference for pull-ups or inserts. The T-shaped diaper was not easier or quicker to change than the diaper. The washable products (Trial 2a) gave diverse results: they were better for leakage at night, but were worse overall for daytime than the other designs. Three-quarters of the women (27/36) found them unacceptable, but nearly two-thirds of men (31/49) found them highly acceptable at night. Findings from the two community trials (Trials 1 and 2a) showed that there were many practical problems in dealing with washable products but, together with the less effective and less expensive products, such as menstrual pads, they were more acceptable at home (and, in the case of washables, at night). This suggests that cost-effective management may involve combining products by using more effective (for a given user) but more expensive designs (e.g. pull-ups) when out and less effective but less expensive designs when at home. The interviews examining the impact of pad use on QoL provided themes and domains that can be further developed into a tool for further evaluation of absorbent products. CONCLUSIONS: This study showed that there were significant and substantial differences between the designs of absorbent products and for moderate/heavy incontinence some designs are better for men/women than others. There was considerable individual variability in preferences and cost-effective management may best be achieved by allowing users to choose combinations of designs for different circumstances within a budget. Further research is needed into the feasibility of providing choice and combinations of designs to users, as well as into the development of more effective washables and of specifically male disposable products. QoL measurement tools are needed for users of absorbent products, as are clinical trials of designs for community-dwelling carer-dependent men and women with moderate/heavy incontinence.

A computerised real-time measurement system to locate the position of the urine stream in designing urine collection devices for women.

A computerised real-time measurement system has been developed and tested for locating the position of the urine stream into a handheld urinal and onto a body-worn pad using arrays of resistive or optical sensors. Experimental data indicates that urine streams were usually scattered over quite a large cross-sectional area (typically 30mm in the anterior/posterior direction) at the point of entry into handheld urinals. However, a correctly placed aperture of length 90mm would have successfully received all the urine from the total of 36 clinical experiments run with seven women. Similarly, experiments to determine the initial position of the urine stream onto body-worn pads indicated that a target area of length 120mm would have received the initial stream of urine from all 54 clinical experiments with 18 women. These data have been used to help with the design of a handheld urinal and a body-worn urine collection interface (the latter using the body-worn pad data) to be used in two variants of a new urine collection device for women (NICMS). Although both resistive and optical sensors provided useful data, the reliability of optical sensors was often compromised by droplets of urine splashing onto light sources or detectors. Future work should focus on protecting them from splashing.

The further development of the active urine collection device: a novel continence management system.

Continence difficulties affect the lives of a substantial minority of the population. Women are far more likely than men to be affected by urinary incontinence but the range of management options for them is limited. There has been considerable interest in developing an external urine collection system for women but without success to date. This paper describes the development and preliminary clinical testing of an active urine collection device (AUCD), which could provide a solution for sufferers. The device uses stored vacuum, protected by a high bubble point filter, to remove urine as quickly as it is produced. This allows a small battery-operated pump to provide the required vacuum, enabling the device to be portable. Two different types of non-invasive patient/device interface were developed, and tested by volunteers: urinal and small pad. The slimline urinal was popular with users although liquid noise was a problem. The pad interface was successful on occasions but further work is necessary to produce a reliable pad. This study has successfully demonstrated that a prototype AUCD liquid handling system can remove urine at clinically relevant flowrates. While further development is required, volunteer tests have shown that the AUCD could be a useful advance in continence management.

A system for logging incontinence events using a simple disposable sensor.

Many elderly people entering residential or nursing care are already incontinent to some degree, relying on incontinence pads to deal with the consequences. A proportion of these people have been shown to exhibit a regular pattern in their incontinence, which opens up the possibility of mitigating the problem by instituting an individual toileting regime for the person. This can reduce their reliance on incontinence pads, both improving their quality of life, and reducing the cost of care. This paper covers the development and evaluation of a sensor for detecting incontinence events, suitable for use in this setting, and describes the design of an associated electronic logger. The devices form part of an assessment system intended to identify a pattern in incontinence where it exists, and to help with the design of the toilet regime for an individual. The requirement is that the system must reliably record incontinence events, and present the information describing them in a manner appropriate to the users of the devices, who are likely to be non-technical and non-specialist.