CARbon Impact of aNesthesic Gas (CARING)

CARbon Impact of aNesthesic Gas - A Carbon Footprint Comparison of Sevoflurane and Desflurane in an Optimized Fresh Gas Flow Protocol

Assessing the impact of anesthesia practice on global warming and carbon footprint becomes part of the standard of care and is growing concern within the anesthesia community. Global Warming Potential (GWP) is a measure of how much a given mass of greenhouse gas contributes to global warming over a specified time period. Inhaled anesthetics have various GWP20: 349 for sevoflurane and 3714 for desflurane. However, GWP20 and CDE20 alone are not sufficient to evaluate the environmental impact of anesthetic gases. Other parameters must be included in the analysis: fresh gas flow (FGF), carrier gas (air, O2, N2O) and potency of the anesthetic gas. Unfortunately, the majority of trials did not fully consider the FGF reduction and the fact that desflurane can be administered with new closed or very low-flow anesthesia circuits as opposed as the recommended 2L/min that must be used for sevoflurane according to its monography in Canada. Most of the calculations were made on a purely theoretical approach that could be different from actual measurements based on a strictly monitored anesthesia practice. When continuous and accurate gas monitoring and analysis is used as recommended nowadays, the use of closed or semi-closed-circuit anesthesia with very low FGF might allow for a reduction of more than 80% of the anesthetic gas administration and its consequent pollution. By properly monitoring the anesthesia depth and analgesia adequacy, the investigators can reduce the gas consumption. The proposed study will aim at determining whether with the help of high-quality monitoring (BIS and NOL) and high-end ventilators that allow minimal fresh gas flow, the use of desflurane remains more polluting than sevoflurane.

Study Overview

• Status: Completed
• Conditions: Anesthesia; Gas; Inhalation
• Intervention / Treatment: Other: Pollution

• Study Type: Observational
• Enrollment (Actual): 58

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Montréal, Quebec, Canada, H1T2M4
      • Hôpital Maisonneuve-Rosemont, CIUSSS de l'Est de l'Ile de Montréal

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

General population undergoing laparoscopic gynecologic, urologic or general surgery

Description

Inclusion Criteria:

• ASA 1-3 patients,
• laparoscopic general, gynecological or urologic surgery requiring general anesthesia without additional regional anesthesia technique
• fully consented,
• BMI < 40,
• age > 18yo,

Exclusion Criteria:

• post-operative need for a neuraxial or regional analgesic technique
• history of active coronary artery disease
• serious cardiac arrhythmia (including atrial fibrillation)
• history of substance abuse
• chronic use of psychotropic and/or opioid drugs
• history of psychiatric diseases with the need of medication
• history of refractory PONV
• allergy or contra-indication to any drug used in the study protocol
• refusal of the patient for participation in the study

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Desflurane; desflurane administration based on a BIS index kept between 40-60 and with use of the semi-closed circuit of the Draeger A500 ventilator and its econometer for an optimized fresh gas flow as low as the O2 consumption allows	Other: Pollution; CO2 equivalent productions related to anesthetic gases use during general anesthesia for laparoscopic surgery
Sevoflurane; sevoflurane administration based on a BIS kept between 40-60 and with use of the semi-closed circuit of the Draeger A500 ventilator with a fixed fresh gas flow of 2L/min as requested in the gas monography	Other: Pollution; CO2 equivalent productions related to anesthetic gases use during general anesthesia for laparoscopic surgery

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CO2 equivalent of volatile inhaled anesthesic gases use in grams	To compare total volatile inhaled anesthetics consumption in CO2 equivalent (grams) per hour during anesthesia for laparoscopic surgery between two groups: Group "D" for Desflurane and group "S" for Sevoflurane	From intubation to end of surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total volatile inhalated anesthesics consumption in mL	To compare the total volatile inhaled anesthetics consumption in mL, mL/h and mL/kg/h during anesthesia for laparoscopic surgery between desflurane and sevoflurane	From intubation to end of surgery
Cost in dollars	To compare the total cost of volatile inhalated anesthesics (mL of gaz x $/mL of gaz) for each group	From intubation to end of surgery
Extubation time in minutes	To compare the extubation time	From stopping anesthesics gases to extubation
Recovery room time in minutes	To compare the time spent in the recovery room	From end of surgery to 240minutes post-surgery

Collaborators and Investigators

• Sponsor: Ciusss de L'Est de l'Île de Montréal

Study record dates

Study Major Dates

• Study Start (ACTUAL): September 25, 2019
• Primary Completion (ACTUAL): January 23, 2020
• Study Completion (ACTUAL): January 23, 2020

Study Registration Dates

• First Submitted: November 6, 2019
• First Submitted That Met QC Criteria: November 12, 2019
• First Posted (ACTUAL): November 15, 2019

Study Record Updates

• Last Update Posted (ACTUAL): January 27, 2021
• Last Update Submitted That Met QC Criteria: January 26, 2021
• Last Verified: January 1, 2021

More Information

Terms related to this study

• Keywords: Desflurane; Environment; Sevoflurane; Fresh gas flow
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Respiratory Aspiration
• Other Study ID Numbers: 2020-1971

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No