摘要:

Intravital video microscopy was used to test superoxide dismutase and a lazaroid analogue, U-74389F, as a pretreatment for ischemia-reperfusion-induced microvascular dysfunction in skeletal muscle. Twenty-two male Wistar rats (350-400 g), anesthetized with sodium pentobarbital (65 mg/kg i.p.), were divided into groups to test the lazaroid analogue U-74389F (3 mg/kg; n = 8), a citric acid/citrate mixture (CS-4; n = 4) used as the vehicle for the lazaroid analogue, superoxide dismutase (SOD, 10 mg/kg; n = 5), and saline (n = 5). Normothermic ischemia of the extensor digitorum longus muscle was induced for 3 h by tightening a tourniquet placed around the limb above the muscle. Measurements of the number of perfused capillaries (CDper; mm-1) and capillary red blood cell velocity (VRBC; mm/s) were made after 30,60 and 90 min of reperfusion. Thirty minutes following release of the tourniquet, all test groups showed a significant drop in CDper. The extent of this reduction was maximal in SOD treated muscles, while it was minimized in the lazaroid-treated muscles following 90 min reperfusion. Hyperemia occurred only in muscles treated with saline or lazaroid. The hyperemia was of limited duration in saline-treated muscles, but lasted the entire reperfusion period following lazaroid treatment. An index of microvascular flow, estimated from the product of VRBC and CDper, indicated that flow was significantly greater in muscles treated with lazaroids as compared with all other groups following the 90-min reperfusion. We conclude that whereas SOD was detrimental, the lazaroid analogue U-74389F improved microvascular perfusion following 3 h of no-flow ischemia and 90 min reperfusion.

ISSN:0167-6865    

DOI:10.1159/000178849

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Percutaneous transiuminal angioplasty (PTA) provokes a huge trauma to the arterial wall and potentially liberates fragments of atherosclerotic material that may impair the microcirculation downstream. Incidence and clinical relevance of such embolisms are not known. This study was aimed at investigating the changes of the skin microcirculation in patients with peripheral arterial occlusive disease undergoing PTA of the lower limbs. Pedal transcutaneous oxygen tension (tcpO2) and nailfold skin microcirculation were measured in 21 patients with disabling peripheral arterial occlusive disease before and after PTA. Sixteen matched patients undergoing arteriography alone were used as controls. The skin microcirculation was investigated at the nailfold of the great toe by the combination of laser Doppler fluxmetry and dynamic capillaroscopy. PTA was successful in all patients. The tcpO2 decreased immediately after PTA (ΔtcpO2 = -5 mm Hg; p < 0.004), whereas it tended to increase (ΔtcpO2 = 1 mm Hg; NS) following arteriography as compared with baseline values. By contrast, blood flow increased in both groups, predominantly for the total circulation in the PTA group and for nutritional circulation (p < 0.0017) in the arteriography group, respectively. Consequently, the ‘nutritional index’, i.e., the index of nutritional versus total microcirculation, was decreased following PTA, particularly following mechanical recanalization (p < 0.02), but did not change in the controls. The changes of this ‘nutritional index’ and those of the tcpO2 were positively correlated (r = 0.4, p = 0.023). The decrease of both the pedal tcpO2 and the index of nutritional versus nonnutritional skin microcirculation and the lack of improvement of the reserve flow following PTA support the view that the procedure generates infraclinical microembolisms downstream in the microcirculation which may become of great clinical importance when PTA is performed in coronary arteries with compromised m

ISSN:0167-6865    

DOI:10.1159/000178850

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Breast cancer treatment often causes chronic arm oedema. Oedema depends on the balance between microvascular filtration and lymph drainage, but little is known about the microvessels in postmastectomy oedema (PMO). We investigated cutaneous capillary density in PMO, since capillary density is one of the factors influencing fluid load on the lymphatic system. Video-capillaroscopy allows the skin microcirculation to be examined in vivo and recorded for later analysis. Patient arm volumes, measured optoelectronically, increased by 30 ± 13%. The forearm skin of each arm was examined in 7 normal subjects (mean age 22 years) and 15 PMO patients (mean age 61 years). Native capillaroscopy was found to underestimate capillary density. Venous congestion increased the number of capillaries detected by native capillaroscopy by 26-28%. Fluorescein detected 19-27% more capillaries than native capillaroscopy. Using fluorescein, no significant difference in mean capillary density was found between the right (50 mm-2) and left (48 mm-2) arms of normal subjects (p = 0.53). Surprisingly, cutaneous capillary density in the swollen arm (33 mm-2) was not significantly less than in nonswollen arms (35 mm-2) of patients, despite a mean 14% increase in skin area. Capillary density decreased significantly with age. Relative to the volume and area changes, the density results indicated that cutaneous neovascularization had occurred in the swollen arm

ISSN:0167-6865    

DOI:10.1159/000178851

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The microcirculation in the skin was assessed in 31 patients with sequelae from local cold injuries (LCI) in the extremities. All patients reported cold intolerance 3-4 years after the primary cold injury, which they sustained during military service. The used methods were laser Doppler fluxmetry, transcutaneous oxygen tension (TcpO2) and vital capillaroscopy. Neurovascular reflexes were stimulated by deep inspiration, digital cuff occlusion of venous and arterial circulation, neck cooling with an ice bag and water immersion at 5 and 15 °C. Unaffected lower or upper extremities were also investigated as part of a search for generalized effects of LCI. During immersion in ice water the cold-induced vasodilation (CIVD or Lewis’ ‘hunting’ reaction) was profoundly delayed or abolished in the affected limbs. These also showed the lowest skin temperatures after 15-20 min of immersion. Additionally, a delayed CIVD was found in the unaffected feet of patients with a previous hand injury. TCpO2 resting values were decreased in the patients, but oxygen reappearance time, oxygen recovery index, postocclusive reactive hyperemia and the venoarterial reflex were normal. No capillary abnormalities were found. In conclusion, LCI induces disturbances in the CIVD, impairs cold tolerance and increases the risk of future cold injuries. These data demonstrate disturbances of reflex mechanisms mediated by the central nervous system. Neurophysiologic factors seem to be more important than ischemic mechanisms in the pathophysiology of late sequelae fr

ISSN:0167-6865    

DOI:10.1159/000178852

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Skin flow recordings with a laser Doppler instrument have not proven useful for evaluation of patients with peripheral arterial occlusive disease. The introduction of a probe using seven fibers suggested a reduction in spatial variation, but few studies using this multiprobe have been published. The present study was designed to compare the multiprobe to the standard probe placed between the knee and the first toe, chosen to fit a future study for amputation levels. The aim was to evaluate the multiprobe for that purpose. A laser Doppler fluxmeter with a standard and a multiprobe was used. Measurements were made in five probe sites in lower limbs of healthy volunteers. Each subject was studied by 30-second recordings during 60 min with both probes. Statistically (p < 0.001) lower flux values were obtained with the multiprobe than with the standard probe. The flux variation between the five probe sites was significantly (p < 0.01) higher with the standard probe than with the multiprobe, but the temporal variation was similar with both probes. The results suggest that the spatial variation in widely separated probe sites is reduced with the multiprobe. The temporal variation was not found to be reduced.

ISSN:0167-6865    

DOI:10.1159/000178853

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178854

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178855

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178856

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178848

出版商:S. Karger AG    

年代:1994

数据来源: Karger