Comparison of the Ecological Footprints of administering Salbutamol by Metered-Dose Inhaler and by Nebulization in Emergency Treatment of Acute Asthma

BackgroundThe scientific evidence indicates little or no difference in the effectiveness or cost of using of metered-dose inhalers (MDIs) versus nebulization to treat acute asthma in the emergency department (ED). However, the use of MDIs raises questions of environmental impact. The objective of this study was to compare the carbon footprint of salbutamol administered by MDI versus nebulization. MethodsApplying a life cycle assessment methodology, we quantified the resources extracted and pollutants emitted by each therapeutic option, from the factory production of medication and equipment to disposal by incineration. Each piece of inventory data was then translated into CO2-equivalent emissions (CO2eq) using the IPCC2021/GWP100 method. Results were estimated for the administration of 1 and 3 treatments of 800 {micro}g of salbutamol by MDI and 5 mg by nebulization (standard doses for adults and children [≥] 24 kg) and compared to the use of a subcompact car. ResultsOne and three ED-administered treatments with salbutamol emit respectively 1.9 and 4.0 kg of CO2eq via MDI versus 0.9 and 1.0 kg via nebulization, which corresponds to 5.5 km and 11.6 km and to 2.7 km and 2.8 km traveled in a subcompact car. Each series of 8 inhalations from an MDI releases 1.1 kg of CO2eq due to emission of the hydrofluoroalkane propellent. InterpretationConsidering the absence or minimal difference in clinical effectiveness, this study suggests that nebulization may be a more eco-efficient administration route than MDIs in the emergency treatment of asthma. Trail registrationN/A TAKE-HOME POINTSO_ST_ABSStudy questionC_ST_ABSWhat is the ecological footprint of metered-dose inhalers compared to nebulization for administering salbutamol when treating a patient with acute asthma in the emergency department? ResultsNebulization was found to have half the carbon footprint of 1 MDI administration and one quarter of 3 MDI administrations. InterpretationImplementing low-emission treatment protocols for acute asthma should be one of many avenues to explore to achieve net-zero greenhouse gas emissions in healthcare services.