Automated Control of End-tidal Volatile Anesthetic Concentration (MIRCONTROL)

Ruhr University of Bochum

Status: Completed

Conditions: Delayed Recovery From Anesthesia

Treatments: Drug: Desflurane; Drug: Sevoflurane; Drug: Isoflurane

Study type: Interventional

Funder types: Other

Identifiers

NCT02342509

RUB 4780-13

Details and patient eligibility

About

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.

Full 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.

Enrollment: 63 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Health Services Research

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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63 participants in 3 patient groups

Desflurane

Experimental group

Description:

Desflurane 5.0-6.0 Vol% (1.0 MAC) in Oxygen (FiO2 0.8-0.95)

Treatment:

Drug: Desflurane

Sevoflurane

Experimental group

Description:

Sevoflurane 1.4-2.1 Vol% (1.0 MAC) in Oxygen (FiO2 0.8-0.95)

Treatment:

Drug: Sevoflurane

Isoflurane

Active Comparator group

Description:

Isoflurane 0.9-1.2 Vol% (1.0 MAC) in Oxygen (FiO2 0.8-0.95)

Treatment:

Drug: Isoflurane