The problem of artifacts in patient monitor data during surgery: a clinical and methodological review.

Artifacts are a significant problem affecting the accurate display of information during surgery. They are also a source of false alarms. A secondary problem is the inadvertent recording of artifactual and inaccurate information in automated record keeping systems.

A novel insulin delivery algorithm in rats with type 1 diabetes: the fading memory proportional-derivative method.

An algorithm designed to automatically control insulin delivery was tested in rats with Type 1 diabetes. This nonlinear algorithm included a fading memory component of proportional and derivative errors in order to simulate normal insulin secretion. Error-weighting functions for the proportional and derivative terms were used with a performance index designed for error adaptation.

Bispectral Index monitoring correlates with sedation scales in brain-injured patients.

Objective: Monitoring critically ill, brain-injured patients with a decreased level of consciousness is challenging. Our goal is to determine in this population the correlation between the Bispectral Index (BIS) and three commonly used sedation agitation scales: the Richmond Agitation-Sedation Scale (RASS), the Sedation-Agitation Scale (SAS) and the Glasgow Coma Scale (GCS) scores.

Design: Prospective, single-blinded observational study.

Estimation of current leakage in left and right ventricular conductance volumetry using a dynamic finite element model.

Leakage of electric current through cardiac structures surrounding the ventricle is a primary source of error during ventricular volume measurements using a conductance catheter. This error can be represented as a leakage volume, VL. VL is generally estimated by a saline-bolus method, and is assumed constant throughout the cardiac cycle.

A new technique to measure and track blood resistivity in intracardiac impedance volumetry.

Objective: To propose and verify a technique by which blood resistivity can be measured continuously and instantaneously with a conductance catheter used to measure ventricular volume by intracardiac impedance volumetry.

Methods: Intracardiac impedance volumetry involves the measurement of ventricular blood volume using a multi-electrode conductance catheter. Ventricular volume measurement with the conductance catheter requires the value of blood resistivity.

Simulation of cardiac conduction system in distributed computer environment.

A high resolution, three dimensional, computer model of the cardiac conduction system has been developed. Cardiac geometry was constructed from sectional images of VHP project of the National Library of Medicine. The heart was modeled as a matrix of cells that fill its anatomical structure.

Real-time continuous measurement of right ventricular volume using a conductance catheter.

The authors propose using a multi-electrode conductance catheter to measure continuous right ventricular volume. True ventricular volume measurements are affected by four main sources of error. 1) field non-uniformity, 2) catheter curvature, 3) blood conductivity changes, and 4) leakage of current through surrounding tissues.