Interest in applying a “lean” philosophy to design has been slowly growing in recent years, but there are still few broadly applicable methodologies and illustrative cases published in the literature to guide lean design processes. Lean approaches promise cost reduction and increased product value, which could be particularly beneficial in product development for low- and middle-income country markets, where value demands are high. We use the clinical need of efficient diabetic foot risk assessment in lowresource healthcare settings to present an example of lean early-stage design of a medical device. The background of existing medical literature and commercial products is intentionally leveraged throughout the design process to streamline development and minimize the need for independent validation of product strategies and design features. Our approach resulted in an efficient design process that generated a novel, purely mechanical plantar pressure evaluation device that can indicate high risk of diabetic foot ulcer in resource-constrained settings. This case provides a practical example of how design processes can be adapted to be leaner where there are large gains from minimizing design cycle time and cost.

Objectives: Approximately 10–15 percent of individuals with diabetes mellitus develop foot ulcers, which precede 85 percent of amputations. Increased oxygen, through the use of hyperbaric oxygen therapy (HBOT), has been suggested to encourage ulcer healing thus reducing the risk of amputation. The objective of this systematic review is to evaluate the efficacy of systemic HBOT for nonhealing ulcers of the lower limb in diabetes patients.

Methods: A systematic search, using controlled and keyword terms focusing on “HBOT” and “lower limb diabetic ulcers,” was conducted. Databases searched included Medline, EMBASE, CINAHL, PubMed, Wiley's Cochrane Library, and Biosis. Randomized controlled trials (RCTs) and observational studies were included. Pooled estimates of outcomes were determined when appropriate.

Results: Of the 654 citations identified, 157 articles underwent full-text review. Data were abstracted from twelve publications (six RCTs and six comparative observational studies). Pooled analysis of the RCT and observational data showed that treatment with HBOT reduced the risk of major amputation by 60 percent (p = .29) and 61 percent (p = .003) compared with standard wound care, respectively. The RCT data revealed that the relative risk of having an unhealed wound following HBOT was 0.54 (p = .10) and 0.24 (p < .0001) based on observational data.

Conclusions: Due to the limited RCT evidence, it is not possible to conclusively establish the benefits and harms of treating diabetic lower limb ulcers with HBOT. No significant effects on amputation rates were found in the RCT evidence and in the high quality studies, no difference was found.

Background: Hyperbaric oxygen therapy (HBOT) has been proposed as an adjunct to standard methods of care for diabetic foot ulcers (DFU). Its use may decrease the risk of infection and lower extremity amputations (LEAs). As part of a Canadian assessment, we estimated the cost-effectiveness and budget impact of HBOT in this application.

Methods: We developed a decision model comparing adjunctive HBOT with standard care alone. The population was a 65-year-old cohort with DFU. The time horizon was 12 years taken from a Ministry of Health perspective. The health states were a healed wound with or without a minor LEA, an unhealed wound with no related surgery, and a major LEA. Efficacy data were based on outcomes reported in studies included in a literature review. Cost and capacity needs for treating DFU patients in Canada were estimated using prevalence data from the literature, and cost and utilization data from government records.

Results: The 12-year cost for patients receiving HBOT was CND$40,695 compared with CND$49,786 for standard care alone. Outcomes were 3.64 quality-adjusted life-years (QALYs) for those receiving HBOT and 3.01 QALYs for controls. Estimated cost to treat all prevalent DFU cases in Canada was CND$14.4–19.7 million/year over 4 years. If seven-person HBOT chambers were used, a further nineteen to thirty-five machines would be required nationally.

Conclusions: Adjunctive HBOT for DFU is cost-effective compared with standard care. Additional HBOT capacity would be needed if it were to be adopted as the standard of care throughout Canada.