Environmental sustainability evidence in critical care medicine: a scoping review

Marko Balan, Thomas Bodley, Kiyan Heybati, Jiawen Deng, Melany Gaetani, Christina Maratta, Michelle Swab, Karen E. A. Burns, Srinivas Murthy

PURPOSE: We sought to conduct a scoping review to summarize the existing literature on environmental sustainability in critical care medicine, methods for measuring intensive care unit (ICU)-related environmental impact, and interventions to improve ICU environmental sustainability. SOURCE: We conducted a systematic search of four databases to identify studies published before October 2024 pertaining to environmental sustainability and assessment of the carbon footprint of ICUs and manually screened selected journals. PRINCIPLE FINDINGS: The combined search strategy identified 1,967 potentially eligible articles. We conducted a full-text review of 149 articles, of which 99 met eligibility criteria. Articles were categorized into five domains: waste management (n = 31), carbon footprint (n = 20), sustainable medication practices (n = 9), energy delivery/consumption (n = 4), and other (n = 39), with four studies classified into two themes owing to overlap in content. Daily material waste in the ICU ranged from 4.9 to 15.2 kg per patient per day. Most studies reported poor waste sorting practices, and several studies reported reductions in waste generation with multicomponent interventions. Three carbon-footprint-themed studies calculated the carbon footprint of ICUs either through life-cycle assessments or material flow analysis. Eleven studies quantified carbon emission reductions using either prospective or theoretical stewardship interventions related to equipment, medications, or ICU care processes. CONCLUSIONS: In this scoping review, we found a rapidly expanding yet fragmented body of evidence on ICU environmental sustainability. Important gaps exist in evidence to guide clinicians on practical bedside strategies and understanding how to implement them to drive meaningful, sustainable change.