Overview
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.
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.
Eligibility
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.