Carbon Footprint of Total Intravenous and Inhalation Anesthesia in the Transcatheter Aortic Valve Replacement Procedure.

OBJECTIVES: To quantify and compare the emissions for deep sedation with total intravenous anesthesia (TIVA) and general anesthesia with inhaled agents during the transcatheter aortic valve replacement procedure.

DESIGN: A retrospective study.

SETTING: A tertiary hospital in Boston, Massachusetts.

PARTICIPANTS: The anesthesia records of 604 consecutive patients who underwent the transcatheter aortic valve replacement procedure between January 1, 2018, and March 31, 2022, were reviewed and analyzed.

INTERVENTIONS: Data were examined and compared in the following 2 groups: general anesthesia with inhaled agents and deep sedation with TIVA.

MEASUREMENTS AND MAIN RESULTS: The gases, drugs, airway management devices, and anesthesia machine electricity were collected and converted into carbon dioxide emissions (CO2 e). The carbon emissions of intravenous medications were converted with the CO2 e data for anesthetic pharmaceuticals from the Parvatker et al. study. For inhaled agents, inhaled anesthetics and oxygen/air flow rate were collected at 15-minute intervals and calculated using the anesthetic gases calculator provided by the Association of Anesthetists. The airway management devices were converted based on life-cycle assessments. The electricity consumed by the anesthesia machine during general anesthesia was estimated from the manufacturer's data (Dräger, GE) and local Energy Information Administration data. The data were analyzed in the chi-squared test or Wilcoxon rank-sum test. There were no significant differences in the patients' demographic characteristics, such as age, sex, weight, height, and body mass index. The patients who received general anesthesia with inhaled agents had statistically higher total CO2 e per case than deep sedation with TIVA (16.188 v 1.518 kg CO2 e; p < 0.001), primarily due to the inhaled agents and secondarily to airway management devices. For deep sedation with TIVA, the major contributors were intravenous medications (71.02%) and airway management devices (16.58%). A subgroup study of patients who received sevoflurane only showed the same trend with less variation.

CONCLUSIONS: The patients who received volatile anesthesia were found to have a higher CO2 e per case. This difference remained after a subgroup analysis evaluating those patients only receiving sevoflurane and after accounting for the differences in the duration of anesthesia. Data from this study and others should be collectively considered as the healthcare profession aims to provide the best care possible for their patients while limiting the harm caused to the environment.