Comparative life cycle assessment of single-use cardiopulmonary bypass devices

Abstract

The purpose of this study is to evaluate the impacts of the common cardiopulmonary bypass device over its life cycle. This represents the first such assessment of a complex medical device, to the best of the authors’ knowledge. This study was motivated by practitioners’ concerns over cardiopulmonary bypass devices constructed mainly of single-use plastics, such as polyvinyl chloride and polycarbonate. The open-source software OpenLCA was used to perform each life cycle assessment with respect to ten common impact categories: global warming, eutrophication, acidification, smog, human health cancer, human health non-cancer, water intake, human health air pollutants, ecotoxicity, and natural resource depletion. The environmental impact was evaluated using the Building for Environmental and Economic Sustainability impact assessment method. To quantify the uncertainty in the results, Monte Carlo simulation was used using 5000 runs. A comparative assessment was conducted to determine the potential trade-offs in each impact category of using alternative construction materials. Incineration as a common disposal option could contribute up to 33 % of total CO2 equivalent emissions over the life cycle of the device. Another 33% of total CO2 equivalent emissions are attributed to polycarbonate used in the construction of devices. Polycarbonate was also implicated as the top contributor to the other impact categories considered, except for human health cancer, which is almost entirely affected by the use of polyvinyl chloride in the device, primarily in the tubes. The accuracy of these results is corroborated by the uncertainty analysis. Lastly, the results show that replacing polycarbonate with polyethylene terephthalate, polypropylene, or polyethylene would be no worse than polycarbonate and provide a significant decrease in almost every impact category. Cardiopulmonary bypass devices are constructed primarily of single-use plastics that have relatively significant impacts in the 10 common categories considered. Alternative disposal methods and replacement of polycarbonate with alternative plastics could dramatically reduce the effects in most impact categories.