Healthy, Surgery
Conditions
Keywords
propofol, Eleveld, BIS, predicted effect site model, non-lineal behavior
Brief summary
in healthy patients undergoing elective surgery, after a very slow induction, using Eleveld's kinetics as a reference, after loss of consciousness (LOC) and intubation, proceed to infuse propofol until 1% burst suppression ratio is obtained. Then return to the LOC concentration. The BISindex predicted by the model and the real one will be evaluated. The evolution of spectral density frequencies over time will also be evaluated.
Detailed description
Eleveld is a recently developed PKPD model of propofol, which includes multiple covariates in its pharmacokinetics. This model, called Universal, includes data from all studies conducted with plasma levels in the world, where the principal investigator (PSV) has been directly involved. For pharmacodynamics (PD), Eleveld, includes processed electroencephalogram (EEG) readings, but only by nominal BIS index. The use of BIS as a unique marker of propofol hypnosis shows multiple limitations as it results from a computer algorithmic application, which can be influenced by drugs, inter-individual variability, among others. Therefore, to determine the effect there are nowadays more accurate tools such as spectrogram processing and determination of alpha power by spectral density (PDS). This project aims to re-evaluate the modelling of the temporal behaviour of the effect in the BIS index, using the reference of the Eleveld kinetic model, associated to a spectrogram that allows the evaluation of the alpha and delta band dynamics as a predictor of the propofol effect. In our study we intend to replace the BIS value by the alpha and delta power progress in decibels (dB) and eventually build a pharmacodynamic (PD) model with a marker more associated to the specific cortical electrical phenomenon.
Interventions
DRUGfixed propofol infusion 15 mg/kg/h until 1% BSR (burst suppression ratio)
after a slow induction with propofol to loss of consiousness (LOC), we proceed to give remifentanil TCI and rocuronium and intubate the patient. After 5 min we infuse 15 mg/kg/h until 1%BSR observe in the BIS monitor. Then we reduce the TCI LOC predicted concentration.
Sponsors
Technical University of Munich
Universidad del Desarrollo
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Intervention model description
healthy patients proposed for elective surgery longer than 60 min, received a standard protocol TCI iv anesthesia with EEG BIS index monitoring
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* ASA I-II patients between 18 and 60 years of age, who undergo elective surgery in the central ward of the Hospital Base San José Osorno, Chile. Consecutive patients from the beginning of the study up to 12 months from the admission of the first patient.
Exclusion criteria
* Emergency surgery patient. * Patients with dementia, delirium or altered state of consciousness. * Full stomach or risk of aspiration. * Allergic to propofol.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| predicted BIS index vs real BIS index | anesthesia | we compare the BIS predicted from the Eleveld model vs the response of our patients uring all the anesthesia procedure |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| evaluation of the evolution of the EEG frequency bands | anesthesia | Evaluate the differents EEG frequency bands at LOC, at maximal perturbation and when we reach again the LOC predicted concentration |
Countries
Chile
Outcome results
None listed