Bispectral Index-Guided Versus Fixed Dose Administration of Desflurane During Balanced Anesthesia With Remifentanil

Seoul National University Hospital48 enrolled

Overview

Balanced anesthesia combining volatile anesthetics and opioids is commonly used in modern anesthesia. The purpose of this study is to compare two methods of administering desflurane, an volatile anesthetic during balanced anesthesia. The investigators hypothesized that administering desflurane at 1 MAC (minimum alveolar concentration) during balanced anesthesia will be more beneficial in terms of stability of the patient's vital signs and hypnotic depth than administering desflurane according to the patient's BIS (bispectral index) value.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

SUPPORTIVE_CARE

Masking

TRIPLE

Enrollment

Conditions

Stabilizing Hypnotic Depth and Vital Sign During Balanced Anesthesia

Interventions

Eligibility

Sex: ALLMin age: 20 YearsMax age: 90 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients scheduled for operation under balanced anesthesia using desflurane and remifentanil Exclusion Criteria: * Refusal of consent * General anesthesia with agents other than desflurane and remifentanil * Patients with allergy to neuromuscular blocker, volatile anesthetics, opioids * History of malignant hyperthermia * Patients taking CNS stimulants * Chronic alcohol abuser * Patients with severe depressed left ventricular function, EF \< 30% * Patients with convulsive disorders * ASA class IV, V, VI * Patients with systolic arterial blood pressure lower than 90mmHg before surgery * Patients needing inotropic infusion during surgery * Anesthesia time less than 30 minutes

Outcomes

Primary Outcomes

The difference of 'wobble' value of the patients' BIS value between the two groups

'Wobble' is a variable that can measure the performance measurement of a pharmacokinetic model, or the reaction of the patient to a drug. We can calculate the performance error from the target of the therapy and the actual measured value, and derive the wobble by a specific formulas, which are described below. PE=(BISmeasured-BIStargeted)x100/BIStargeted MDPEi = median{PEij, j=1,…,Ni} MDAPEi = median{\|PEij\|, j=1,…,Ni} Wobblei = median{\|PEij-MDPEi\|, j=1,…,Ni} Divergence = slope{\|PEij\|, j=1,…,Ni}

Time frame: Every second from 10 minutes after skin incision to 10 minutes before surgery end.

Secondary Outcomes

The difference of 'wobble' value of the patients' systolic arterial blood pressure value between the two groups

Described above

Time frame: Every 2.5 minutes from 10 minutes after skin incision to 10 minutes before surgery end