Dynamic variables are the best predictors of fluid responsiveness in patients under general anesthesia and mechanical ventilation; namely, respiratory variations in pulse pressure and in the plethysmographic waveform. However, these variables have potential limitations. Our aim was to evaluate their intraoperative applicability. We extracted clinical data from all anesthesia procedures performe...

background pulse-oximetry (spo2) widely uses as a help tools for therapeutic interventions in the pediatric intensive care units (picu). the aim of this study was to evaluate the validity of spo2 in measuring of oxygenation index (oi) in children. materials and methods in a descriptive analytical study, 100 patients who were admitted to picu tabriz children's hospital were studied. oxygena...

BACKGROUND The information contained in arterial pressure waveforms is probably underused by most clinicians who manage critically ill patients. It is not generally known that an aortic pressure wave can be synthesized by applying a generalized transfer function to the radial arterial pressure wave. We validated a commercially available system, SphygmoCo (PWV Medical, Sydney). METHODS Ascendi...

Arterial pressure is a cyclic phenomenon characterized by a pressure wave oscillating around the mean blood pressure, from diastolic to systolic blood pressure, defining the pulse pressure. Aortic input impedance is a measure of the opposition of the circulation to an oscillatory flow input (stroke volume generated by heart work). Aortic input impedance integrates factors opposing LV ejection, ...

Introduction The non-invasive assessment of cardiovascular function by means of the peripheral arterial pulse has gained substantial interest in recent years due to the integration of sensor technology and the ubiquitous application of microprocessors. In its most basic use, the peripheral pulse provides a signal that establishes the presence of a beating heart and quantifies the cardiac rhythm...

The Functional Electrical Stimulator design using monophasic spike-exponential waveform was proposed and described in this study. The monophasic square waveform has benefit in generating an action potential, but it could cause side effects such as toxic caused by the electrode polarization. The square waveform signal which the frequency and pulse width could be modulated was manipulated to be t...

BACKGROUND Respiratory variations in the pulse oximeter plethysmographic waveform amplitude (deltaPOP) are sensitive to changes in preload and can predict fluid responsiveness in mechanically ventilated patients. However, they cannot be easily calculated from a bedside monitor. Pleth variability index (PVI, Masimo Corp., Irvine, CA) is a new algorithm that automatically calculates deltaPOP. The...

Conventional pulse oximetry uses two wavelengths of light (red and infrared) transmitted through a finger and a photodetector to analyze arterial hemoglobin oxygen saturation and pulse rate. Recent advances in pulse oximetry include: extended analysis of the photo plethysmographic waveform; use of multiple wavelengths of light to quantify methemoglobin, carboxyhemoglobin and total hemoglobin co...