Search results
Results from the WOW.Com Content Network
Flow-Volume loop showing successful FVC maneuver. Positive values represent expiration, negative values represent inspiration. At the start of the test both flow and volume are equal to zero (representing the volume in the spirometer rather than the lung). The trace moves clockwise for expiration followed by inspiration.
Pressure-Volume loops showing end-systolic pressure volume relationship. End-systolic pressure volume relationship (ESPVR) describes the maximal pressure that can be developed by the ventricle at any given LV volume. This implies that the PV loop cannot cross over the line defining ESPVR for any given contractile state.
Very useful information can be derived by examination and analysis of individual loops or series of loops, for example: the horizontal distance between the top-left corner and the bottom-right corner of each loop is the stroke volume [5] the line joining the top-left corner of several loops is the contractile or inotropic state. [6]
The minimum and maximum volumes (V max and V min) from each loop in the series of loops are plotted on a graph. V max and V min lines are extrapolated and at their point of intersection, where V max is equal to V min, must be zero—conductance is parallel conductance only. The volume at this point is the correction volume.
For premium support please call: 800-290-4726 more ways to reach us
Major factors influencing cardiac output – heart rate and stroke volume, both of which are variable. [1]In cardiac physiology, cardiac output (CO), also known as heart output and often denoted by the symbols , ˙, or ˙, [2] is the volumetric flow rate of the heart's pumping output: that is, the volume of blood being pumped by a single ventricle of the heart, per unit time (usually measured ...
The flow coefficient of a device is a relative measure of its efficiency at allowing fluid flow. It describes the relationship between the pressure drop across an orifice valve or other assembly and the corresponding flow rate. Mathematically the flow coefficient C v (or flow-capacity rating of valve) can be expressed as
In most contexts a mention of rate of fluid flow is likely to refer to the volumetric rate. In hydrometry, the volumetric flow rate is known as discharge. Volumetric flow rate should not be confused with volumetric flux, as defined by Darcy's law and represented by the symbol q, with units of m 3 /(m 2 ·s), that is, m·s −1.