摘要:

The wick technique and the blister suction technique are the most common methods for sampling of subcutaneous interstitial tissue fluid in man. The blister suction technique has the advantage of being less invasive than the wick technique, but the reliability of this method is still controversial. The aim of this study was to evaluate whether the simpler blister suction technique using large (8 mm) blisters could replace the wick technique in the investigation of patients with postreconstructive leg edema. Fifteen patients with ipsilateral leg edema following infrainguinal bypass surgery for lower limb atherosclerosis were investigated. The two different fluid sampling techniques were applied simultaneously on both legs. The concentration of total protein and albumin as well as colloid osmotic pressure of the subcutaneous interstitial tissue fluid in the leg were measured in all fluid samples. Agreement analysis was applied to compare the two methods, while the correspondence between the methods was estimated with linear regression analysis. The agreement index was found to be positive for all variables from the operated as well as from the contralateral control limb. Furthermore, all values were within the agreement limit. The best agreement between the two methods was found for colloid osmotic pressure on the operated side. According to the equation of linear regression, there was a slight overestimation of the wick values compared to the observed blister values. In conclusion, there was a good methodological agreement between the blister suction technique and the wick technique. The less invasive blister suction technique should be regarded as the method of choice for the investigation of subcutaneous interstitial tissue fluid in patients with postreconstructive leg edema.

ISSN:0167-6865    

DOI:10.1159/000179159

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The microcirculation of inflamed human skin was assessed non-invasively using the techniques of laser Doppler flowmetry, hydrogen clearance flowmetry, visible-light spectrophotometry and transcutaneous oximetry. Increases in red cell flux (from a mean of 1.1 in normal skin to 11.5 V in inflamed skin) and haemoglobin saturation (from 49 to 87 and from 38 to 60% with macro- and micro-lightguide spectrophotometry, respectively), contrasted with decreases in transcutaneous pO2 (from 86 to 39 mm Hg). The more intense reactions tended to lead to a lower value of oxygen tension at the surface of the skin than the weaker reactions. A barrier to oxygen diffusion, presented by the infiltrating inflammatory cells, has previously been suggested as the reason for this. The oxygen extraction rate was estimated from spectrophotometry and blood flow measurements, using the Fick principle, and this showed an increase (from 42 to 130 arbitrary units, AU). When the skin was heated to 44 °C there was no change seen in this parameter in inflamed skin compared with normal skin (from 114 to 133 and from 14.1 to 14.5 AU), although it tended to increase in the stronger reactions while decreasing in the weaker ones. Extraction measured by a cuff occlusion method (with the same skin temperature) did show an increase however (from 28 to 57 and from 3.2 to 7.2 AU), and this was more pronounced in the stronger reactions. It is suggested that there may be a critical transit time for a red cell, during which it is able to effectively off-load its oxygen. In conditions of very high flow the transit time is reduced and oxygen extraction may be compromised further when diffusion is already limited

ISSN:0167-6865    

DOI:10.1159/000179160

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Disturbances in sympathetic cutaneous vasomotor reflexes may be of pathogenetic importance in several microvascular problems. Laser Doppler fluxmetry (LDF) enables one to study the influence of sympathetic reflexes on skin blood flow. A matter of concern is the high variability of skin blood flow and its reactivity to sympathetic reflex test resulting in a poor reproducibility. In this study we evaluated two sympathetic stimulation tests, distant cooling and inspiratory gasp, and their influence on LDF-measured skin blood flow of the pulp of the big toe in 63 healthy volunteers. No age or sex dependency of the LDF test results was found. Absolute and relative LDF decrease during distant cooling was highly variable between the subjects (LDF decrease, mean ± SD: 0.7 ± 5.3%) compared to an LDF decrease of 46.5 ± 3.1% during an inspiratory gasp test. The reproducibility, however, was better for the distant cooling test [coefficient of variation (CV): distant cooling: 5.8%, inspiratory gasp test: 35.4%]. With the use of a thermostatically controlled LDF probe holder fixed at a temperature of 36 ° C, the short-term reproducibility of the two sympathetic vasomotor tests did not improve, probably because of a steady increase in baseline skin blood flow during the test. Surprisingly long-term variability of the percentage LDF decrease during the inspiratory gasp test, performed with the heated LDF probe, was lower compared to the short-term variability (CV 19.2 vs. 39.0%, p < 0.05). In conclusion to study sympathetic skin vasomotor reflexes with LDF, vasoconstriction during the inspiratory gasp test was more uniform compared to the distant cooling test, although the latter was more reproducible. Measuring skin blood flow reactivity with a heated LDF probe (36 °C) did not improve reproducibi

ISSN:0167-6865    

DOI:10.1159/000179161

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The introduction of the servonulling technique by Wiederhielm in 1963 allowed for the first time continuous and dynamic recording of capillary blood pressure (CP). In 1979 Mahler used this technique for the first measurements in humans. Data analysis was limited to manual analysis of chart recordings. Nowadays fast analog-digital converters with ay high sampling frequency are used for data recordings, and consequently there is a need for an easy-to-use software for data analysis of CP data. The presented newly developed computer software allows analysis of mean CP, taking into account the zero pressure measured before and after capillary cannulation. The simultaneously recorded electrocardiogram R wave is used as a marker for the calculation of the mean capillary pulse pressure waves and of their characteristic data. This may help determine the significance of the capillary pulse waveform for microvascular function. Changes in the pulse waveform may be the only detectable difference between patients and healthy controls. Analysis of simultaneously recorded temperature, the display of markers for valid readings, and the possibility of excluding nonvalid data or artefacts from analysis are additional features.

ISSN:0167-6865    

DOI:10.1159/000179162

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The aim of the present study was to examine the nailfold capillary morphology and dynamics in treated chronic heart failure (CHF) in relation to parameters of left ventricular structure and function. Twenty patients with CHF class II according to the New York Heart Association underwent a capillaroscopic examination at the finger nailfold using a computerized videophotometric system (Capiflow®) at rest and after 1 min arterial occlusion. Study parameters ere number, length and diameter of the capillaries as well as capillary blood velocity (CBV). Further experiments included echocardiography and determination of left ventricular ejection fraction by Tc scintigraphy. Nailfold capillaries in established CHF are enlarged and the CBV is dramatically decreased. The reactive hyperemic response to 1 min arterial occlusion is attenuated. CBV correlates positively with left ventricular ejection fraction (r = 0.61, p = 0.01) and inversely with left ventricular end-diastolic (r = -0.56, p = 0.04) and end-systolic (r = -0.69, p = 0.01) diameters. The time-to-peak flow after 1 min arterial occlusion is positively related (r = 0.68, p < 0.05) to the duration of CHF. Our data indicate that finger microcirculation in CHF deteriorates as a function of the severity and duration of heart failure

ISSN:0167-6865    

DOI:10.1159/000179163

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Hyperoxemia is known to alter tissue oxygenation, which in the brain results in a scattered and an uneven distribution of cerebrocortical tissue oxygen pressures (PtO2). This study examined the effect of ritanserin (a highly specific serotonin receptor antagonist, 5-HT2) on the PtO2 distribution during hyperoxemia. The measurements of brain oxygenation were performed on the motor cortex in anesthetized pigs with a multiwire Clark-type microelectrode. Ritanserin was administered (0.035 mg/kg i.v.) during hyperoxemia (inspired oxygen fraction = 0.70). In 4 of 5 animals, the disturbed oxygenation that was registered during hyperoxemia was normalized after the ritanserin injection. These results indicate that serotonin may be involved in the regulation of brain oxygenation during hyperoxemia, and they also suggest that serotonin may be a link in the coupling between the oxygen metabolism and the regulation of blood flow in the brain.

ISSN:0167-6865    

DOI:10.1159/000179164

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Most studies of neutrophil-endothelial interactions in vivo necessarily require the use of general anesthetic agents which are well known to be immunosuppressive. By using whole-mount preparations of the rat mesoappendix, we were able to study tumor necrosis factor alpha (TNF-α) induced neutrophil adhesion to the mesenteric venular endothelium in vivo without necessarily using general anesthesia. TNF-α significantly increased venular-neutrophil accumulation in a dose-dependent manner; accumulation was markedly increased at 1,2, and 4 h, but returned to baseline after 24 h. After these preliminary dose-response and time-course studies, we evaluated the influence of standard clinically effective doses of several commonly used anesthetic agents (thiopental, pentobarbital, ketamine, α-chloralose, methoxyflurane, and halothane) on the extent of neutrophil-venular accumulation induced 2 h after intraperitoneal injection of 0.4 mg/kg TNF-α, compared to unanesthetized rats. All general anesthetics tested, with the exception of methoxyflurane, significantly suppressed this response. In most cases this suppression was striking (from 60 to 85%) such that a statistically significant proinflammatory response was obscured. Although methoxyflurane also tended to suppress this response to TNF-α, it was the only agent that allowed the response to be clearly seen. Because anesthesia markedly suppresses cytokine-induced neutrophil-venular adhesion, this model should provide an important complementary technique to the classical in vivo microcirculatory approaches which do necessarily require general anesth

ISSN:0167-6865    

DOI:10.1159/000179165

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000179166

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000179167

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000179168

出版商:S. Karger AG    

年代:1996

数据来源: Karger