Sara Khosravi

• Technology Transfer Officer , Industry Liaison Office, University of British Columbia
• Chair at University of British Columbia

Introduction: iControl v3 is a system for closed-loop control of propofol and remifentanil anesthesia in adults. It includes a touch-screen user interface, the NeuroSENSE EEG monitor, two Alaris infusion devices and speakers for audible alarms. Previous versions of the system have been clinically evaluated [1]. The system has been designed for inve...

During closed-loop control, a drug infusion is continually adjusted according to a measure of clinical effect (e.g., an electroencephalographic depth of hypnosis (DoH) index). Inconsistency in population-derived pediatric pharmacokinetic/pharmacodynamic models and the large interpatient variability observed in children suggest a role for closed-loo...

Closed-loop control of anesthesia is expected to decrease drug dosage and wake up time while increasing patient safety and decreasing the work load of the anesthesiologist. The potential of closed-loop control in anesthesia has been demonstrated in several clinical studies. One of the challenges in the development of a closed-loop system that can b...

Background: The effect of intravenous anesthetic drugs is traditionally modeled using pharmacokinetic (PK) and pharma-codynamic (PD) models. However, a physiological meaningful set of PD parameters is not required for controller design and is not essential for prediction of closed-loop performance provided that the experimental conditions for ident...

This paper presents a new monitor-decoupled model of propofol pharmacodynamics (PD) using the state entropy (SE) as the clinical endpoint of interest. In our model, the dynamics of the entropy monitor are separated from the PD response of the patient by explicitly accounting for the model of the entropy monitor in the PD identification process. The...

This investigation aimed to develop a pediatric pharmacodynamic model of propofol-induced tidal volume depression towards an ultimate goal of developing a dosing schedule that would preserve spontaneous breathing following a loading dose of propofol. Fifty two ASA 1 and 2 children aged 6-15 year presenting for gastrointestinal endoscopy were enroll...

To compare the population pharmacodynamic (PD) models of propofol in children derived using two-stage and mixed-effect modeling approaches. Fifty-two ASA 1 and 2 children aged 6-15 years presenting for gastrointestinal endoscopy were administered a loading dose of 4 mg·kg(-1) of propofol intravenously at an infusion rate determined by a randomizati...

This paper presents two alternative approaches to characterize the pharmacodynamics of propofol anesthesia in children, using State Entropy as a clinical end point. The first approach is the traditional approach where the pharmacodynamic model is described in terms of an effect-site equilibration rate constant and the Hill equation. In the second a...

Background: Pediatric pharmacokinetic (PK) models [1,2] used for target-controlled infusion (TCI) of propofol, frequently employ an effect site equilibration rate constant, k e0 , that is derived from adult studies. Pharmacodynamic (PD) differences between adults and children, however, dictate that it is unacceptable to extrapolate available adult...

Previous work of estimating needle trajectories using un-calibrated camera-based tracking ("touchless" needle guide) is extended here to real ultrasound imaging. Using 4D ultrasound, this technique can be used as a needle guide during percutaneous procedures. A pair of miniature cameras captures images and the ultrasound system captures a volume as...

A pose estimation method is proposed for measuring the position and orientation of a needle. The technique is to be used as a touchless needle guide system for guidance of percutaneous procedures with 4D ultrasound. A pair of uncalibrated, light-weight USB cameras is used as inputs. A database is prepared offline, from the needle line estimated fro...