BACKGROUND We evaluated the ability of an infrared photoplethysmography arterial waveform (continuous non-invasive arterial pressure, CNAP) to estimate arterial pulse pressure variation (PPV). We compared the ability of non-invasive PPV to predict fluid responsiveness with invasive PPV, respiratory variation of pulse contour-derived stroke volume, and changes in cardiac index induced by passive...

The hemodynamic response to sympathetic nerve stimulation (SNS) was studied in canine lung lobes isolated in situ and perfused with a pulsatile pump. For the same input pulse, both the rate of rise and the rate of fall of pulmonary arterial pressure increased during SNS; the peak systolic pressure was also higher during SNS, whereas diastolic pressure levels were either at, or below, control le...

Studies of the physical characteristics of large arteries (Roy, 1880; Bramwell, 1924; Hallock and Benson 1937) have shown that the aorta is more elastic in the young than in the elderly. As age advances the great vessels dilate while their distensibility diminishes and the range of pressure over which the wall is approximately elastic is reduced. These changes are the result of the tension in t...

During severe asthma, paradoxic pulse may result from increased impedance to left ventricular ejection, mechanical impairment of left ventricular filling by ventricular interdependence or decreased pulmonary venous return augmented by hypovolemia. We studied the effect of reversible blood volume expansion by MAST inflation during severe attacks of asthma. Ten patients with clinically detectable...

The shear swirling flow vibration cementing (SSFVC) technique rotates the downhole eccentric cascade by circulating cementing fluid. It makes the casing eccentrically revolve at high speed around the borehole axis. It produces strong agitation action to the annulus fluid, makes it in the state of shear turbulent flow, and results in the formation of pulse pressure which affects the surrounding ...

blood velocity as an indicator of fluid responsiveness in ventilated patients with septic shock. Chest 2001; 119: 867–73 16 Marik PE, Cavallazzi R, Vasu T, Hirani A. Dynamic changes in arterial waveform derived variables and fluid responsiveness in mechanically ventilated patients. A systematic review of the literature. Crit Care Med 2009; 37: 2642–7 17 Benes J, Chytra I, Altmann P, et al. Intr...