Volume Capillary Flow Research Articles

Comparison of the value of cardiac output with different methods of hemodynamic monitoring

The article deals with the physical basis for determining the parameters of central, peripheral hemodynamics and oxygen saturation with the help of photoplethysmography.A comparative study of the parameters of cardiac output and volume capillary peripheral blood flow in 34 patients with polytrauma was conducted. The purpose of the study was to consider the possibilities of modern photoplethysymometric technologies for assessing the state of peripheral and central hemodynamics, by comparing their results with the results of echosonographic study of central hemodynamics.Indicators of central hemodynamics in the examined patients were determined using the photoplethysmographic technology of Nihon Kohden, as well as with transthoracic echosonography. The evaluation of the state of the peripheral capillary blood flow was determinate with using Masimo Rainbow’s photoplace micrometric technology.The decrease of cardiac output and peripheral capillary blood flow with the increase of the severity of shock was revealed. Successful anti-shock measures that ensure the growth of cardiac output and arterial vascular tone, were associated with an increase in volume capillary flow. When comparing the results of photoplethysmographic and ultrasound technologies of hemodynamic evaluation, results are obtained that match the value of the values of cardiac output with a linear correlation coefficient of Pearson 0.983. Photoplethysmographic monitoring accurately reflects the clinical picture of shock and the effectiveness of intensive care.

Capillary blood flow: videodensitometry in the atherosclerotic patient.

Recently the noninvasive technique of videomicroscopy has demonstrated qualitative morphologic changes in the nutritional skin capillaries in atherosclerotic (ATS) patients. The purpose of this study is to quantitatively examine the ATS microcirculation and effects induced by reconstructive surgery. Capillary blood flow velocity (CBV) of single vessels within the nail fold of the large toe was measured by dual-sensor videodensitometry in 14 ATS patients (age 45 to 80 years) and 11 age-matched controls. In addition to CBV, capillary diameter (CD) and the number of flow-active capillaries (FC) were also measured at constant temperature. Of the 14 patients, eight had measurements repeated 1 week after reconstructive surgery. The measurements were obtained at rest and then periodically after a 45-second period of pedal inflow occlusion. Respective group averages at rest for CBV, CD, and FC for the 14 ATS patients were as follows: 0.16 mm/sec, 10.5 micron, and 6.8 capillaries per field. Corresponding values for the control subjects were 0.10 mm/sec, 8.7 micron, and 5.3 capillaries per field. Combining CBV, CD, and FC into a measurement of volume capillary flow yielded a value of 281 pl/sec/mm2 for the patients and only 85 pl/sec/mm2 for the controls (p less than 0.02). Peak postocclusion CBV significantly increased, whereas FC significantly decreased relative to rest in the control group; however, the only patient group that responded to occlusion-induced ischemia was the postoperative group. In these patients there was a decrease in CBV and an increase in FC relative to rest. These responses are exactly opposite to those in the age-matched controls.(ABSTRACT TRUNCATED AT 250 WORDS)