Automated Control of End-tidal Volatile Anesthetic Concentration

Not Applicable

Completed

• Conditions: Delayed Recovery From Anesthesia
• Interventions: Drug: Desflurane; Drug: Isoflurane; Drug: Sevoflurane

• Registration Number: NCT02342509
• Lead Sponsor: Ruhr University of Bochum

Brief Summary

The new MIRUS system as well as the established AnaConDa system uses a reflector to conserve volatile anaesthetics (VA). Both systems act with commercially available ICU ventilators. In contrast to AnaConDa the MIRUS includes an automated control of end-tidal VA concentrations. In this study the investigators compared feasibility, costs and recovery times after anaesthesia with isoflurane (ISO), sevoflurane (SEVO) or desflurane (DES) in ventilated and spontaneously breathing patients.

Detailed Description

The study was approved by the appropriate Institutional Review Board. After written informed consent 63 ASA I-III patients undergoing elective hip or knee replacement surgery under general anesthesia were included. Patients were randomly organized into 3 groups (20-22 each). Anesthesia was induced with intravenous anaesthetics. After tracheal intubation MIRUS automatically adjusted the end-tidal VA concentration to 1.0 MAC. Patients were ventilated with the Puritan Bennett 840 ICU ventilator. After 1 h of anaesthesia with 1.0 MAC the ventilator mode was switched from SIMV V+ (totally controlled ventilation, "passive patient", with a tidal volume of 8 ml/IBW) to proportional assist ventilation (PAV) with 50% support ("active patient"). At the end of surgery the MIRUS system was stopped (MAC set to 0.0) and recovery times were measured.

Study Timeline

• Study Start: 2014-09
• Primary Completion: 2014-12
• Study Completion: 2014-12
• Status Verified: 2015-01
• Study First Submitted: 2015-01-06
• Study First Submitted QC: 2015-01-14
• Last Update Submitted: 2015-01-14
• Study First Posted: 2015-01-21
• Last Update Posted: 2015-01-21

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 63

Inclusion Criteria

• Signing of the informed consent document (patient or relatives).
• Patient age 18 years or older.
• ASA I-III

Exclusion Criteria

• ASA IV patients
• Epidural or spinal analgesia
• Allergy or known hypersensitivity to any of the study drugs
• Patients with known or suspected genetic susceptibility to malignant hyperthermia
• Previous participation in this trial
• Participation in another clinical trial within 4 weeks prior to selection.
• Pregnant women

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Desflurane	Desflurane	Desflurane 5.0-6.0 Vol% (1.0 MAC) in Oxygen (FiO2 0.8-0.95)
Isoflurane	Isoflurane	Isoflurane 0.9-1.2 Vol% (1.0 MAC) in Oxygen (FiO2 0.8-0.95)
Sevoflurane	Sevoflurane	Sevoflurane 1.4-2.1 Vol% (1.0 MAC) in Oxygen (FiO2 0.8-0.95)

Primary Outcome Measures

Name	Time	Method
volatile anaesthetics (VA) consumption	duration of anesthesia: max. 3 h

Secondary Outcome Measures

Name	Time	Method
recovery times	duration post anesthesia care: max. 8 h after anesthesia