Reevaluation Prediction of the Effect Site Propofol Eleveld Model Using Slow and Fast Induction (fast or slow E)

Comparison of the Site Effect Model Prediction and BIS Predicted by Eleveld for Propofol in Slow and Rapid Inductions

Patients ASA1-2, 18 to 70 years old, scheduled for elective surgery with personal conset to participate, will be randomised into two groups using different induction mode. TCI effect site mode induction or TCI plasma mode induction both using the Elevelt PKPD propofol model. Standard monitoring (EKG, SaO2, PCo2et, NIAP), and Conox/ and or BIS EEG monitor to evaluate the prediction.

The model's prediction will be compared with values provided by the Conox/BIS index for both groups and between them. The study will be conducted during the 20 minutes after Loss of responsiveness.

Study Overview

• Status: Completed
• Conditions: Pharmacodynamics; Anesthesia for Elective Surgery Patients; Anesthesia Brain Monitor
• Intervention / Treatment: Drug: Evaluation of the prediction of from the propofol PKPD model including in TCI pumps using fast (Effect site mode TCI) or slow (plasma TCI mode) induction

Detailed Description

Patients aged 18 to 70 years will be included. Patients allergic to propofol are excluded. Eleveld's PKPD model for propofol includes covariates for adjustment in administration with target-controlled infusion pumps. Induction to the site of effect will be performed using EC60 for each age, while slow induction will use the target plasma modality, starting at a target of 3 ug/ml and increasing by 0.5 ug/ml every 3 minutes until loss of consciousness. This is defined as the loss of response to voice and shoulder tap. The 20 minutes following loss of consciousness will be evaluated.

Biometric and gender characteristics of both groups, concomitant pathologies, and surgical times will be compared.

The temporal evolution of the propofol effect site predicted by the Eleveld model will be compared between the two types of induction using EEG (CONOX or BIS). To obtain the EEG index prediction by Eleveld it will be use the Tiva trainer software 2.0, simulating the evolution of the kinetics and effect site calculated by Eleveld in the infudion TCI pumps.

It is estimated that 20 patients per group are required to find a 20% difference in predicted versus actual EEG index with 90% power.

Statistical methods:

1. Data analysis tool: Stata 10 software

2. Statistics

   • Summary: Mean (central tendency) and standard deviation (dispersion)
   • Association: Student's t-test for continuous quantitative variables and Fisher's exact test for dichotomous variables.

• Study Type: Observational
• Enrollment (Actual): 70

Contacts and Locations

Study Locations

• Chile
  • Los Lagos Region
    • Osorno, Los Lagos Region, Chile, 5290000
      • Hospital Base San Jose de Osorno

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients ASA1-2, 18-70 years, scheduled for elective surgery longer than 1 hour

Description

Inclusion Criteria: patients ASA 1-2 scheduled for elective surgery, Exclusion Criteria: patients with psychiatric disorders, allergic to propofol, not giving their consent to participate

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Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group 1: the prediction of the Eleveld propofol model in effect site mode TCI induction; Patients ASA 1-2, 18 to 70 years, will be induced using propofol TCI in effect site mode EC60 of the Eleveld PKPD model and compared with the EEG CONOX behavior, If lost of responsiveness (LOR) was not reached, we climb up 0,5 ug/ml every 3 min. At LOR calculated effect site concentration will be used as reference to mantain anesthesia level.	Drug: Evaluation of the prediction of from the propofol PKPD model including in TCI pumps using fast (Effect site mode TCI) or slow (plasma TCI mode) induction; Using TCI technology and EEG monitoring (CONOX) we will induce loss of responsiveness using the fast induction (Group 1) or slow induction (Group 2) and compare the prediction of the effect site model (PD) in each type of induction.
Group 2: the prediction of the Eleveld propofol model in TCI plasma mode; Patients ASA1-2, 18-70 years, scheduled for elective surgery longer than 1 hour. Induced with TCI plasma mode using the Eleveld PKPD model. The infusion will begin using a target plasma of 3 ug/ml, and scale every 3 minutes in 0,5 ug/ml until Loss of responsiveness (LOR). At LOR the calculated effect site concentration will be used as reference to mantain anesthesia level. EEG (CONOX or BIS) will be used to evaluate the prediction of the model.	Drug: Evaluation of the prediction of from the propofol PKPD model including in TCI pumps using fast (Effect site mode TCI) or slow (plasma TCI mode) induction; Using TCI technology and EEG monitoring (CONOX) we will induce loss of responsiveness using the fast induction (Group 1) or slow induction (Group 2) and compare the prediction of the effect site model (PD) in each type of induction.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prediction of the efect site propofol Eleveld model	The comparison betwen predicted and actual CONOX/BIS index will be made in two scenario: TCI effect site mode induction versus TCI plasma mode induction	The data will be retrieved directly from the infusion pumps and EEGs up to 20 minutes after the loss of clinical consciousness.

Collaborators and Investigators

• Sponsor: Pablo O. Sepulveda
• Investigators: Study Director: José Gonzalez Gonzalez, PHD, Departamento de Investigación Hospital osorno

Publications and helpful links

General Publications

• Coetzee E, Coetzee JF, Haasbroek M. Predictive pharmacodynamic performance of the Eleveld pharmacokinetic-pharmacodynamic model for propofol: comparison of predicted and measured bispectral index. Br J Anaesth. 2024 Oct;133(4):785-792. doi: 10.1016/j.bja.2024.06.041. Epub 2024 Aug 23.

Helpful Links

• this study discuss about the problem of the Eleveld effect site prediction using diferent induction flows

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2025
• Primary Completion (Actual): September 15, 2025
• Study Completion (Actual): September 15, 2025

Study Registration Dates

• First Submitted: November 14, 2025
• First Submitted That Met QC Criteria: November 14, 2025
• First Posted (Actual): November 19, 2025

Study Record Updates

• Last Update Posted (Actual): November 19, 2025
• Last Update Submitted That Met QC Criteria: November 14, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Propofol, Eleveld model, induction flow, CONOX,
• Additional Relevant MeSH Terms: Therapeutics; Combined Modality Therapy; Neoadjuvant Therapy
• Other Study ID Numbers: Hospital Base San José Osoro

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Part of the analysis will be conducted by Matthias Kreuzer Techische Universität München
• IPD Sharing Time Frame: from 3 November 2025 to March 2026
• IPD Sharing Access Criteria: EEG data and concentration data calculated for each patient will be shared in individual folders via Google Drive.
• IPD Sharing Supporting Information Type: SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No