Chirurgisches Forum fur experimentelle und klinische Forschung最新文献

Regional myocardial blood flow (MBF) and left ventricular (LV) function were measured in 18 dogs after 60 min hypothermic (14-16 degrees C) arrest with (group I) and without cardioplegia (group II). Regardless whether postischemic LV function was severely (group II) or only moderately (group I) impaired, the amount of MBF and its transmural distribution was not significantly altered after 30 min reperfusion. In contrast to topical hypothermia, additional cardioplegia maintained metabolic regulation of coronary flow.

Coagulation factors and plasma proteins are significantly decreased in patients with hyperdynamic septic shock. Besides the activation of the coagulation system, the endotoxin-induced release of granulocyte proteases is responsible for a septic disseminated intravascular coagulation. In this situation special emphasis should be placed on the levels of antithrombin III regarding application of heparin.

Our experimental work was concerned with the healing process of fresh homologous osteochondral grafts in the knee joints of 45 sheep. The ultrastructural investigations pointed clearly to the fact that the cells of fresh homografts completely survive under optimal conditions. Neither transformation nor metaplasia were evident.

In four gastric fistula dogs we studied the effect of cimetidine (5 mg/kg/h) and somatostatin (10 microgram/kg/h), alone or in combination, on gastric secretion stimulated by histamine (160 microgram/kg/h) or pentagastrin (6 microgram/kg/h). Acid and pepsin output after histamine stimulation was more reduced by cimetidine than after pentagastrin stimulation. Somatostatin showed an inhibitory effect only after pentagastrin stimulation. The most effective reduction, both on the degree of inhibition and on duration after cessation of the inhibitors, was seen after the combination of cimetidine/somatostatin. These results give some clinical aspects for the use of these two agents.

Livers from inbred DA rats were transplanted orthotopically into inbred BN rats. Within 15 days all animals died due to rejection of the transplant. However, when rats were treated with Cyclosporin A (four different regimens) they survived for at least 60 days, even if therapy was withdrawn at day 28. It could be shown that the histologic changes in the graft stood in an inverse relationship to the extent of immunosuppressive therapy.

Simple end-to-end anastomoses were performed in the common carotid and femoral arteries and in the jugular and femoral veins of dogs. In other dogs, lateral sutures (running) consisting of absorbable material made from polyglycolic acid were inserted. No occlusions, aneurysms, or infections occurred in the arteries. Without heparin, the patency rate after up to 234 days was 98%. In veins, the observation period was 60 days and a patency rate of 83% was found. All vessels were studied by angiography and by light and electron microscopy. Additionally, an original method of hemodynamic assessment was used (Turbulence Index). The alternating effect of morphological variations in the vessel wall and the degree of blood flow disturbance was evident.

High pressure exceeding 1000 mm Hg are measured during reaming of the narrow cavity with ASIF instruments after osteotomy of the sheep's tibia. Histologic evaluation 8 weeks after intramedullary nailing shows obliteration of the canalis a. nutritiae and smaller cortical vessels with fat and bone particles. The internal circumference of the cortex remains nonvital. Revascularization and bone remodeling is proceeding in a mainly centripetal direction.

In six beagles femoral head blood flow is measured with radioactive microspheres. When intra-articular pressure of the hip joint is increased by 50 mm Hg, blood flow is diminished to 48%. Reducing intra-articular pressure to the initial level increases femoral head blood flow to 78%. The results support the demand for immediate pressure relief of hemarthrosis.

The results of impedance plethysmographic examination were evaluated by a mathematical curve analysis. The magnitude of the exponential coefficient of the saturation and discharge function provides a highly accurate measure of the loss of functionality. The percentage change in the flow rate may be obtained by substitution of the exponential coefficients in a model formula.