Letter to Editor
Carolina Frederico
Abstract
Following the recent publication of our article in REDAR (Rev. Española de Anestesia y Reanimación) entitled “Comparison of the Cortínez and the Schnider models during effect-site TCI, at a target of 3 mcg/ml, in healthy volunteers." we want to emphasize that this is a clinical study, which demonstrates that Cortinez’s Model can be used in non-obese patients. The reasons for this are: the Cortinez’s data included normal-weight patients from Schnider`s study; the model included weight allometric adjustments for Volumes and Clearance. We decided to quantify the time of LOC and ROC, Bispectral Index, Blood Pressure, Heart Rate, Non-invasive Cardiac Output, and correlated with predicted concentration and mass of drug calculated by each Model in the same volunteer. The Non-invasive Cardiac Output is an easy interpreting tool, and it is directly related with the propofol’s pharmacokinetic in the first 5 minutes of the infusion. After analysing our data, the Cortínez’s model showed a better predictive ability at the moment of loss of consciousness than Schnider’s model [1]. Cortinez estimates a higher bolus induction compared to Schnider, due to its slower Ke0 (Tpeak 2.1 min-1), without generating significant changes in hemodynamics or the Cardiac Output during induction or maintenance of anaesthesia [2]. The methodology of our study is based on measurement of clinical parameters and the data obtained are relevant to anaesthesiologists in their daily practice.