Target-controlled Infusion Anesthesia and Post-induction Hypotension

Acibadem University

Status: Completed

Conditions: Hemodynamic Instability; General Anesthesia

Treatments: Other: Anesthesia induction with Target controlled infusions (TCI); Other: Manual anesthesia induction

Study type: Interventional

Funder types: Other

Identifiers

NCT05708638

ATADEK 2022-18/04

Details and patient eligibility

About

Hemodynamic changes during induction of anesthesia may have adverse outcomes and should therefore be avoided. The decrease in blood pressure during induction of anesthesia with propofol is due to a decrease in systemic vascular resistance or cardiac output and may be increased by the concomitant use of other drugs such as remifentanil. Target controlled infusion (TCI) system aims to reach the theoretically targeted blood or brain concentration of anesthetic agents based on the patient's age, weight, and height, with computer-assisted algorithms. In manual anesthesia induction, anesthetic agents are administered at a fixed dose and rate adjusted according to the patient's weight, which may cause hypotension in patients with low cardiovascular performance. As target-controlled infusion (TCI) obviates the need to calculate the infusion rate manually, the use of TCI may provide a better hemodynamic profile during anesthesia induction This study was designed to test the hypothesis that propofol by TCI anesthesia induction is associated with a lower hypotension rate when compared with manual anesthesia induction

Full description

Maintaining normotension is one of the top priorities for anesthesiologists due to its negative effects. Although there are a lot of studies and knowledge on the topic approximately 20-30% of patients develop post-induction hypotension. Mostly it occurs due to the adverse effects of anesthetics such as a decrease in systemic vascular resistance or cardiac output and the interplay between them. The risk can be minimized in two steps: first by identifying high-risk patients, and second with tight control of hemodynamic parameters. As a second step, tight hemodynamic control during induction may be done using target-controlled infusion (TCI) systems, which systems help to adjust the dosage to the needs of each patient by measuring hypnotic effects through the bispectral index (BIS).

TCI models for propofol have been previously compared with manual infusions, however, it is not clear whether it still contributes to or triggers hemodynamic deterioration. Therefore in this study, the investigators' aim is to determine the effect of two different anesthesia techniques on the development of postinduction hypotension through hemodynamic parameters monitored by the pressure recording analytical method (PRAM). The secondary aim is to identify risk factors that can predict postinduction hypotension

Enrollment: 200 patients

Sex: All

Ages: 18 to 90 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients with the American Society of Anesthesiology physical status 1-3
• Underwent major elective surgery
• Required intra-arterial blood pressure monitoring before induction.

Exclusion criteria

• Under 18 years of age
• Arrhythmia (atrial fibrillation, frequent premature beat)
• Severe valvular heart disease
• Morbid obesity
• Intubation difficulty
• Drug addiction
• Treatment with opiates
• Pregnancy
• Emergency surgery

Trial design

Primary purpose: Screening

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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200 participants in 2 patient groups

Patients who were assigned to have manual anesthesia induction group with propofol

Active Comparator group

Description:

Patients who were assigned to have a manual anesthesia induction group, propofol was administered 2-3 mg/kg in 1-2 minutes to achieve a level of hypnosis measured by bispectral index ( BIS ) of 35-60.

Treatment:

Other: Manual anesthesia induction

Patients who were assigned to have target controlled infusions ( TCI) induction with propofol

Active Comparator group

Description:

Patients who were assigned to have TCI induction had the target effect site concentration (Ce) of propofol (Ce) set at 3 μg ml-1 using the Schneider model and subsequently modified to achieve and maintain a level of hypnosis measured by BIS of 35-55

Treatment:

Other: Anesthesia induction with Target controlled infusions (TCI)