Evaluation of Equivalent Minimum Alveolar Concentration (eMAC) During Propofol/Remifentanil Anesthesia

Zhang Haopeng

Status: Completed

Conditions: General Anaesthesia

Treatments: Drug: Low Remifentanil; Drug: Propofol; Procedure: tetanic electrical stimulation; Procedure: Intubation; Drug: Heigh Remifentanil

Study type: Interventional

Funder types: Other

Identifiers

NCT05789992

202302

Details and patient eligibility

About

The aim of this study is to verify the accuracy of eMAC compared to Bispectral Index (BIS) for depth and nociceptive stimulation monitoring of anesthesia during general anesthesia.

Full description

eMAC is a new index based on response surface model for evaluating anesthesia state and anti-nociceptive stimulation levels. To valid it's clinical accuracy, a protocol was designed.

Patients will be allocated to receive a specific effect-site concentration of remifentanil and propofol during tonic electrical stimulation (5s, 50mA) and intubation. The concentration combinations include the electrical stimulation combination (effector chamber concentration random: remifentanil 0-3 ng/ml, propofol 3-5 ug/ml) and the intubation combination (effector chamber concentration random: remifentanil 3-5 ng/ml, propofol 3-5 ug/ml). All combinations were decided before operation. Every combination had a 5 min equilibration period, and the vital signs (Heart Rate, Blood pressure, any body movement) and BIS, eMAC will be recorded before and after the electrical stimulation and intubation. After this period, patients will be randomly allocated to receive an intravenous anesthesia or intravenous combined anesthesia, and regular anesthesia is executed. This study only records vital signs and BIS, eMAC during maintenance period of perioperative.

Enrollment: 62 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Patients undergoing elective surgery under general anesthesia;
2. Patients with ASA rating I~III;
3. The age of the patient is more than 18 years old;
4. The informed consent has been signed;

Exclusion criteria

1. Patients who are participating in other trials;
2. Patients with cognitive impairment, mental illness or taking psychotropic drugs within three months;
3. Patients with a history of stroke;
4. Patients with a history of alcoholism (long-term drinking more than 5 years, daily white wine consumption ≥ 50ml);
5. Pregnant women;
6. Patients with BMI>30;
7. Patients and family members who are unwilling to participate after understanding the research content;
8. According to the evaluation of the researcher, the actual condition is not suitable for the patients participating in this trial.

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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62 participants in 4 patient groups

Group 1 BIS under tetanic electrical stimulation

Active Comparator group

Description:

During tetanic electrical stimulation, and with propofol(random:3-5ug/ml) and remifentanil(random:0-3ng/ml), the response (body movement or hemodynamic change) was observed, and recorded it's BIS.

Treatment:

Drug: Propofol

Procedure: tetanic electrical stimulation

Drug: Low Remifentanil

Group 2 eMAC under tetanic electrical stimulation

Active Comparator group

Description:

During tetanic electrical stimulation or intubation, and with propofol(random:3-5ug/ml) and remifentanil(random:0-3ng/ml), the response (body movement or hemodynamic change) was observed, and recorded it's eMAC.

Treatment:

Drug: Propofol

Procedure: tetanic electrical stimulation

Drug: Low Remifentanil

Group 3 BIS under intubation

Active Comparator group

Description:

During intubation, and with propofol(random:3-5ug/ml) and remifentanil(random:3-5ng/ml), the response (body movement or hemodynamic change) was observed, and recorded it's BIS.

Treatment:

Procedure: Intubation

Drug: Heigh Remifentanil

Drug: Propofol

Group 4 eMAC under intubation

Active Comparator group

Description:

During intubation, and with propofol(random:3-5ug/ml) and remifentanil(random:3-5ng/ml), the response (body movement or hemodynamic change) was observed, and recorded it's eMAC.

Treatment:

Procedure: Intubation

Drug: Heigh Remifentanil

Drug: Propofol