多巴胺或多巴胺复合去甲肾上腺素对肝移植术中患者血液动力学、氧代谢及肾功能的影响

目的评价原位肝脏移植术(OLT)中持续输注多巴胺或多巴胺复合去甲肾上腺素对血液动力学、组织氧代谢和肾功能的影响。方法拟行OLT的患者30例,ASAⅢ或Ⅳ级,随机分为2组 (n=15)。A组:术中持续输注多巴胺,初始输注速率为1-3μg·kg-1·min-1;B组:术中持续输注多巴胺复合去甲肾上腺素,初始输注速率分别为1-3μg·kg-1·min-1和0．03μg·kg-1·min-1,多巴胺输注速率不超过5μg·kg-1·min-1;术中两组均调节输注速率维持MAP 60-80 mm Hg。分别于切皮前即刻、切肝期1 h、无肝期1 h、新肝期1h和术毕测定血液动力学、组织代谢和肾功能指标。结果两组HR、 MAP均维持较平稳。无肝期两组CVP、MPAP、PAWP、CO、CI、DO2、VO2降低(P<0．05);SVR和SVRI升高(P<0．05),但均在正常范围内。术中PVR、PVRI、pH及SvO2均较平稳。乳酸浓度增高并持续到术毕。两组术中Cr和BUN均在正常范围,B组总尿量高于A组(P相似文献   

Free flap monitoring with continuous tissue oxygen tension measurement

Intraoperative and postoperative free flap monitoring by means of oxygen tension measurement was carried out in 11 patients. We used an invasive flexible microcatheter that allowed for measurement of oxygen tension in all types of free flaps. Two cases of the measured flaps were buried free flaps which do not allow monitoring by clinical assessment. All flaps monitored in this study survived. One case of displacement of the microcatheter occurred. In one patient, the tissue pO₂ monitor successfully detected early vascular thrombosis with subsequent reoperation and salvage of the free flap.     

Evaluation of the influence of the aqueous phase bioconstituent environment on the F-19 T1 of perfluorocarbon blood substitute emulsions

Oxygen-sensitive F-19 magnetic resonance imaging of perfluorocarbon compounds requires that fluorocarbon T1 changes correlate with the local Po₂ and not with the composition of the surrounding aqueous phase. The influence of various bioconstituents and paramagnetic ions within the aqueous phase on the F-19 fluorocarbon phase T1 for PFC emulsions was evaluated at 0.14 and 0.66 T. T1 was measured for FC-43, perflubron, and a fluorinated surfactant. Controlled variables introduced in the aqueous phase included annex solution constituents, blood, pH changes, and Gd-DTPA. For a constant Po₂, the F-19 T1s were independent of the emulsion constituents, blood concentration, and pH. For FC-43 and perflubron, F-19 T1 was independent of the Gd-DTPA concentration, while the aqueous phase T1 decreased by more than an order of magnitude. XMO-10 (smallest emulsion particle size) showed a slight decrease in F-19 T1 with increasing Gd-DTPA concentration at 0.66 T.     

Improved haemorheology associated with a reduction in plasma fibrinogen and LDL in patients being treated by heparin-induced extracorporeal LDL precipitation (HELP)

Heparin-induced Extracorporeal LDL-Precipitation (HELP) is an effective procedure for the elimination of both plasma LDL and fibrinogen. In 10 adult patients with severe type II hyperlipoproteinemia, a single HELP treatment of 3 1 plasma led to an acute decrease in the average plasma viscosity (PV) from 1.30 to 1.1 mPas. At the same time, an even more marked decrease in the mean erythrocyte aggregation rate from a pathological value of 7.9% to a value of 3.7% (normal range less than 5%) was observed. Long-term studies on five patients demonstrated a lasting improvement in these two haemorheological variables. The acute rheological changes were also accompanied by an improvement in polarographically determined muscle oxygen tension. Mean oxygen tension values measured in both the m.biceps brachii and the m.tibialis anterior in five patients before and after a single HELP treatment increased from 30 +/- 4 to 37 +/- 7 mmHg and from 27 +/- 2 to 31 +/- 3 mmHg respectively. These results may provide an explanation for the rapid improvement in patients' clinical symptoms such as angina pectoris and in stress electrocardiogram which have been observed during HELP therapy.     

Investigation of melt agglomeration process with a hydrophobic binder in combination with sucrose stearate

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Dynamics of lipid adsorption at the electrified water∣1,2-dichloroethane interface

A recently introduced setup to measure the dynamic interfacial tension of expanding drops was used to compare the adsorption behaviour of a series of lipids at the electrified water∣dichloroethane interface. Phospholipids with saturated carbon chains of different length (DMPC, DPPC, DSPC, DAPC, DBPC), an unsaturated phospholipid (DOPC) and an ethanolamine (DSPE) were compared. It was found that the adsorption decreases with increasing chain length. Also, the increase of the flow rate reduces the degree of adsorption effectively. On the timescale of the experiments, the DSPE, DAPC and DBPC adsorption showed no potential dependence, whereas the adsorption of DOPC was stronger than that of the saturated lipids. Adsorption was modelled using the Langmuir adsorption isotherm; the potential dependence of adsorption is discussed.     

Demographic and clinical characteristics of patients with episodic migraine versus chronic daily headache

We compared data from 243 patients with episodic migraine (EM) and 132 patients with chronic daily headache (CDH). We divided the matter group into those with tension-type headache only (CDH Type 1) and those with headaches having migrainous features (CDH Types 2+3) and compared each with the EM group and all three groups with one another. CDH Type l patients differed from those in the other groups by virtue of gender (more often male) and mean age at headache onset (older). The CDH Types 2+3 and EM groups differed only in that the former were more likely to have undergone a brain-imaging study. These data suggest that CDH Type 1 may represent a distinct headache syndrome, while CDH Types 2+3 closely resemble episodic migraine.     

Inhibition of GABA-gated chloride channel function by arachidonic acid

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