Clinical trial NCT04210570: Decreasing Environmental Impact and Costs of Using Inhalational Anesthetic With a Carbon Dioxide Membrane Filter System
Official title: Decreasing Environmental Impact and Costs of Using Inhalational Anesthetics by Replacing Chemical Absorbers With an Innovative Carbon Dioxide Membrane Filter System - a Prospective, Randomized, Clinical Trial
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Anesthesia
Inhalation; Vapor
Keywords: Anesthesia
Inhalation
Vapour
CO2 Absorber
Minimal Flow Anesthesia
Memsorb
Healthcare Cost
Greenhouse gas
Environment Healthcare
Lead sponsor: Western University, Canada
Sponsor class: OTHER
First posted: 2019-12-24
Enrollment: 510
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: HEALTH_SERVICES_RESEARCH

Brief summary: Efficient inhalational anesthetic delivery requires the use of low-flow air and oxygen to reduce drug waste and minimize workspace contamination and environmental pollution. Currently, excess anesthetic gas is scavenged and removed from the operating room via the hospital ventilation system, where it is released into the atmosphere. CO2 is removed from the anesthesia circuit by the use of CO2 removal systems to prevent re-breathing and potential hypercarbia.

Carbon dioxide is currently removed using chemical granulate absorbers (CGAs), which trap CO2 in the granules that are later disposed of when absorption capacity is reached. They require replacement approximately every other day when used in moderate to high volume surgical centres, placing a costly burden on the healthcare system and environment (landfill).

One of the more concerning downfalls of using CGAs is the potential for the inhalational anesthetics to react with the granules and potentially produce toxic byproducts known as compounds A-E that are nephrotoxic and neurotoxic and require excess amounts of anesthetic gas to dilute.

This excess use of anesthetics gases places a financial burden on the healthcare system and has a detrimental impact on the environment. The vast majority of the gases used are eventually released into the environment with little to no degradation where they accumulate in the troposphere and act as greenhouse gases.

DMF Medical has created Memsorb, a new CO2 filtration membrane. Memsorb can remove CO2 from the anesthesia circuit without the use of CGAs, thereby eliminating the potential for toxic byproducts and allowing for significantly lower air and oxygen flow to be used, resulting in less use of inhalational anesthetics. Memsorb uses a polymeric membrane (similar to the ones used in oxygenators for cardiac surgery) that selectively allows CO2 to leave the rebreathing system, while maintaining the inhalational anesthetic in the circuit.

The lifespan of Memsorb is at least 12 months, resulting in less particulate waste and a decreased cost to the healthcare system.

We wish to evaluate the ability and efficacy of Memsorb in removing CO2 from the anesthesia circuit while maintaining physiologic minute volume ventilation, as compared to the traditional CGAs in a variety of surgical procedures, patient populations, and anesthesia gas flows.


Eligibility criteria: Inclusion Criteria:

* ASA I - III
* Elective surgical procedure
* Laparoscopic surgery for study aim III

Exclusion Criteria:

* ASA \> IV
* Emergency surgery
* Severe respiratory disease (eg Asthma)
* Raised intracranial pressure
* Regional anesthesia
* Absence of arterial line for study aim III
* Self-reported pregnancy

Primary outcomes:
measure: Effectiveness of Memsorb compared to CGA to eliminate CO2
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Impact of Memsorb, using minimal flow anesthesia (≤ 0.50 L/min), on the amount of inhalational anesthetic (ml) used, compared to standard practice
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Effectiveness of using Memsorb during ventilation for removal of CO2 in laparoscopic surgeries resulting in high CO2 exposure, compared to CGAs
timeFrame: Duration of general anesthesia (up to 12 hours)
Secondary outcomes:
measure: Amount of inhaled anesthetics used
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Duration of anesthesia
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Water build up in anesthesia circuit
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Freshgas flow during general anesthesia
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Number of CGAs used during the study period
timeFrame: Duration of general anesthesia (up to 12 hours)
measure: Minute volume ventilation
timeFrame: Duration of general anesthesia (up to 12 hours)
Other outcomes:
Locations:
city: London
country: Canada
facility: LHSC
state: Ontario
Study officials:
References: