Comparison of Different Ventilator and Vaporizer Technologies to Study Economic and Environmental Implications

NCT ID: NCT04851314

Last Updated: 2021-08-10

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 110 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-02-14
• Study Completion Date: 2019-11-08

Brief Summary

The purpose of this study is to test whether or not the use of a low volume ventilator in an anesthesia machine reduces anesthetic costs significantly as compared to other high volume machines. The study will compare the a low-flow anesthesia machine to a traditional anesthesia machine during routine elective general surgery in patients with ASA ratings of 1-2 under general anesthesia receiving standard care.

Detailed Description

The study member will screen for potential subjects using the UCIMC surgical schedule. If a subject is deemed ineligible based on the inclusion and exclusion criteria after reviewing the medical history, his/her record will be discarded. No records will be retained from ineligible subjects. After discussing with the patient's surgeon, study team member will initiate the informed consent process by approaching each eligible subject to explain the study and what it entails. The Lead Researcher will address all questions and concerns from the subject before asking the subject to sign the research consent form.

The GE anesthesia machines currently owned by the operating room will be used to serve as the comparator to the Flow-i machine. The high volume anesthesia machines do not use a low volume system. Subjects will be randomized by recruitment day. On a given recruitment day, all consented subjects will receive anesthesia from one of two groups:

(1) MAQUET FLOW-i device (2) GE anesthetic device

Time points for both groups include:

T0: Time of intubation, when volatile anesthetic are typically first delivered to the patient. We will use 15L/min fresh gas flow, while dictating tidal volumes of 6-8 mL/kg ideal body weight and a PEEP of 6 centimeters of water (cm H2O) in accordance with current best practices.

T1: Time of incision, which typically represents the time of reaching steady state conditions of volatile anesthetic delivery. We will reduce fresh gas flow to 2 L/min in accordance with local practice and weigh the vaporizer at this point, allowing us to measure comparative anesthetic consumption during this wash-in time period (T0-T1).

T2: Time of anesthetic weaning, typically the time when preparing for patient emergence begins by discontinuing the delivery of volatile anesthetics to the patient. The vaporizer will be re- weighed at this point, allowing us to measure comparative anesthetic consumption at steady state maintenance of anesthetic depth (T1-T2) Logically, we will also be able to use T0-T2 in order to understand total comparative anesthetic consumption.

Aside from the randomization to either Group 1 or Group 2, there will be no changes in the surgical or anesthetic procedure, including the medication or treatments given to the subjects as determined by the treating physician. All subjects will receive general anesthesia in accordance to local practice.

For this study, the vaporizer(s) will be weighed on a tared scale before research procedures commence, after induction, and when the gas is shut off during weaning of anesthesia in preparation for extubation to calculate the amount consumed during this time (grams/minute). In addition, the following variables will be recorded:

Subject weight (kg) Tidal Volume (TV) Respiratory Rate (RR) 9 of 24

Positive end-expiratory pressure (PEEP) Fresh Gas Flow Volume % gas End Tidal (%) Time of extubation Time when Aldrete score > 8

This is not a physician-blinded study being that the physical characteristics of the standard delivery units are distinguishable from the MAQUET FLOW-i machine.

All MAC concentrations are standard of care: After the surgical procedure, patient will be assessed for time to reach Aldrete score greater than 8, level of pain and time to extubation. Their medical records will be reviewed to determine need for times and adverse events. Patients will not be contacted for study-related follow-up after they are discharged from recovery.

No photographs or audio/video recording will be collected for this study.

Subject's Privacy:

The study team member will screen for potential subjects using the UCIMC surgical schedule. If a subject is deemed ineligible based on the inclusion and exclusion criteria after reviewing the medical history, his/her record will be discarded. No records will be retained from ineligible subjects.

Study team member will approach each eligible patient to explain the study and what it entails. The study team member will address all questions and concerns from the subjects before asking the patient to sign the research consent form.

Conditions

Anesthetic Gas Consumption and Cost-Effectiveness

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

ICU certified ventilator

Participants assigned to receive ventilation with the ICU certified ventilator

Group Type: ACTIVE_COMPARATOR

ICU certified ventilator

Intervention Type: DEVICE

Examine anesthetic consumption rates

Non-ICU certified ventilator

Participants assigned to receive ventilation with the Non-ICU certified ventilator

Group Type: ACTIVE_COMPARATOR

Non-ICU certified ventilator

Intervention Type: DEVICE

Examine anesthetic consumption rates

Interventions

ICU certified ventilator

Examine anesthetic consumption rates

Intervention Type: DEVICE

Non-ICU certified ventilator

Examine anesthetic consumption rates

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Age 18-65 years
• Undergo surgery under general anesthesia in UCI Medical Center
• Agree to sign the consent and HIPAA forms
• Subjects who are able to receive sevoflurane

Exclusion Criteria

• Subjects under the age of 18
• Chronic Obstructive Pulmonary Disease (COPD)
• Body Mass Index (BMI) > 30
• ASA > 2
• Pregnant females
• Procedures less than 2 hours
• Those with known sensitivity to sevoflurane or other halogenated agents; those with known or suspected susceptibility to malignant hyperthermia
• Severe Cardiovascular Disease: Left Ventricular Ejection Fraction (LVEF) < 30%

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of California, Irvine

OTHER

Sponsor Role: lead

Responsible Party

Robert Ryan Field

HS/Assistant Clinical Professor; Neuroanesthesiology Clinical Director

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Robert R Field, MD

Role: PRINCIPAL_INVESTIGATOR

University of California, Irvine

Locations

University of California, Irvine Medical Center

Orange, California, United States

Countries

United States

References

Avramov MN, Griffin JD, White PF. The effect of fresh gas flow and anesthetic technique on the ability to control acute hemodynamic responses during surgery. Anesth Analg. 1998 Sep;87(3):666-70. doi: 10.1097/00000539-199809000-00033.

Reference Type: BACKGROUND

PMID: 9728850 (View on PubMed)

Choi SU, Shin HW, Jung HI, Park JY, Yoon SZ, Lee YS, Kim WY, Chang SH. Control of the haemodynamic response to surgical stimuli in semi-closed circuit or closed circuit anaesthesia using a multifunctional anaesthesia system. J Int Med Res. 2010 Sep-Oct;38(5):1637-44. doi: 10.1177/147323001003800508.

Reference Type: BACKGROUND

PMID: 21309477 (View on PubMed)

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Document Type: Informed Consent Form

View Document

Other Identifiers

UCIANES11 [HS# 2014-1248]

Identifier Type: -

Identifier Source: org_study_id