Journal of clinical monitoring and computing
-
J Clin Monit Comput · Jan 2000
Estimation of jugular venous O2 saturation from cerebral oximetry or arterial O2 saturation during isocapnic hypoxia.
Near-infrared spectroscopy (NIRS) has the potential for providing valuable information about oxygen delivery to the brain. However, questions have been raised about the accuracy of these measurements. This study was undertaken to compare noninvasive cerebral saturation measurements to jugular venous saturation under conditions of hypoxia and hypercapnia. ⋯ Cerebral oxygen saturation measured by cerebral oximetry compares well to the measured SjvO2 in normal subjects, despite multiple physiological reasons for differences. The closer relationship of SjvO2 to rSO2 than SaO2 under the conditions of these experiments indicates that the measurement reflects primarily intracranial saturation. However, outcome studies under clinical conditions are needed to determine the clinical utility of cerebral oximetry.
-
J Clin Monit Comput · Jan 2000
A proposed method for the measurement of anesthetist care variability.
Some critical events in anesthesiology occur as seemingly preventable misadventures, their exact origins indeterminable. Inexperienced anesthetists, anesthesia machine malfunctions, lack of vigilance and human error inevitably initiate some incidents. Anesthesia training improves recognition and decision-making. Avoiding crisis initiation and amelioration of those that do occur is one role of the consultant anesthesiologist. Safe patient care requires medical and procedural knowledge, technical expertise, and control of resources in a complex milieu. Anesthesia simulators are clinical laboratories where anesthetists can sharpen both cognitive and manual skills. Dynamic scenarios allow opportunities for anesthetists to explore and experience crises as they develop and apply their knowledge while attempting to manage these events. Simulator-based scenarios are reproducible and large amounts of useful data can be collected and saved. The authors hypothesize these data can be utilized to compare performance of anesthetists and to measure improvement of individual anesthetists over time. ⋯ It is suggested that the use of the techniques mentioned here may be of value in the development of a standardized testing protocol for anesthetists.
-
J Clin Monit Comput · Jan 2000
Partial CO2 rebreathing indirect Fick technique for non-invasive measurement of cardiac output.
Evaluation in animals of a non-invasive and continuous cardiac output monitoring system based on partial carbon-dioxide (CO2) rebreathing indirect Fick technique. ⋯ The partial CO2 rebreathing technique for measurement of cardiac output is non-invasive, automated, and based on the well accepted Fick principle. The limits of agreement between NICO and TDco is within the recommended value for NICO to be a clinically acceptable method for cardiac output measurement. The results of this canine study show that NICO performed as well, and in some cases better, than other currently available non-invasive cardiac output techniques over a wide range of cardiac outputs.
-
J Clin Monit Comput · Jan 2000
Accuracy of deadspace free ventilatory measurements for lung function testing in ventilated newborns: a simulation study.
A deadspace free method based on simultaneous ventilatory measurements in the inspiratory and expiratory limb of the ventilator circuit was compared to the conventional endotracheal method where the flow is measured between ETT and Y-Piece. The aim of our study was to find out how the arrangement of this setup affects the measuring accuracy of 1) the ventilatory and 2) the lung mechanical parameters by means of a computer simulation. ⋯ The dead space free method can be used for accurate ventilatory measurements during mechanical ventilation. However, for lung mechanic measurements in very low birth weight infants the position of the PNTs must be as short as possible.
-
J Clin Monit Comput · Jan 2000
Comparative Study Clinical TrialNon-invasive estimation of cardiac output in critical care patients.
This study was carried out to compare cardiac output measurements determined by thermodilution and by Portapres, a non-invasive system. ⋯ To date, Portapres measurements cannot replace thermodilution cardiac output estimations. Fluctuations of finger arterial perfusion due to hemodynamic instability, hypothermia and catecholamines may be responsible for problems of Portapres use in critically ill patients.