Zeitschrift fur experimentelle Chirurgie, Transplantation, und kunstliche Organe : Organ der Sektion Experimentelle Chirurgie der Gesellschaft fur Chirurgie der DDR最新文献

Monitoring of exocrine graft function and pancreatic juice cytology have proved to be a reliable method of detection of pancreas allograft rejection. In order to confirm these clinical findings and to define further parameters, experimental work is still needed. The rat was chosen for these experiments and a technique of pancreatic juice procurement developed. In five animals a fully implantable closed reservoir-catheter system was used. For the prevention of bacterial contamination it was necessary to install a mixture of antibiotics and culture medium into the reservoir. Pancreatic juice was procured daily under general anaesthesia. During the observation time of 14 days no further complications were encountered with the exception of one catheter dislocation. The mean amount of juice of 1 cc per day has proved to be sufficient for various enzyme estimations as well as for juice cytology.

Due to a want of oxygen in the breathing air there appears a change of the volume of muscle cells, of ion concentrations inside and outside the cells as well as disturbances the structure and membrane potential. These changes are connected with changes of the passive electrical properties of the muscle tissue. Measuring the electrical impedance of the muscle it is possible to diagnose alterations as shock and disorder of microcirculation in an easy way continuously. Investigations with rats show that a decrease of the oxygen content in the inspiration air effects characteristic changes in muscle impedance. These changes are reversible in normoxia.

The histologic estimation of the subcutaneous connective-tissue reaction at implants forms an important part of the biocompatibility test. The connective-tissue capsulae around titanium implants in man, guinea-pig, and Wistar-rat were analysed by a special test system because of the question concerning the transmission of results of animal experiments on the man. The subsidence process of the thickness of the connective-tissue capsule and of the cell count per measuring fields were represented in dependence on the time. The findings showed the fundamental similar course of wound healing in man, guinea-pig, and Wistar-rat by the influence of an implant.

Sutures of the colon can be insufficient or leaking. This leads in some cases to a peritonitis or sepsis sometimes with lethal outcome. Therefore experiments in animals were performed to investigate the effect of additional applied biogenic glue. Especially in the beginning of the wound healing, at the 4th postoperative day, the firmness could be improved by fibrin glue. The bursting pressure of fibrin glue sealed colon sutures was 94 mmHg, whereas only 66 mmHg was observed in the control group. This additional firmness remains over the whole observation time of 3 weeks. An intensified proliferation of the connective tissue is responsible for this observation which could be substantiated by histological investigations and by measuring the thickness of the scar. If biogenic glue is used in animals it can have the consequence that the recipient reacts with the production of antibodies, since the components of the glue are proteins from different species. Investigations of the serum of animals which had been treated with fibrin glue revealed in a part of them precipitating antibodies against fibrinogen. With regard to this observation a second application of biogenic glue must be done with the necessary precaution.

The technique of experimental operative procedures in the distal area of the brain stem in the reach of the fourth brain ventricle is described in rabbits. The experiments were carried out in 25 rabbits (breed great-chinchilla, body-weight 4.5 to 5.25 kg) of both sexes. All manipulations were performed in general anesthesia. The best methods for endotracheal intubation of the rabbit and for the surgical technique in the floor of the fourth ventricle were searched.

The biocompatibility of 10 materials used for surgical drainage was evaluated in a cytotoxicity test and in rat subcutaneous tissue implantation test. All rubber materials and silikolatex were found to be cytotoxic. There was no correspondence of the results of the cytotoxicity test with those of the implantation test. Therefore various procedures for biocompatibility-testing should be used.

In animal experiments on domestic pigs the behaviour of hyperthermically denatured autogenic compact bone grafts after orthotopic replantation was investigated histologically. It was shown that the inductive osteogenetic celldifferentiation of the lair tissue caused by the autogenetic osteoimplantation depends on the location relationship of the replanted bone grafts to the lair bone tissue. This differentiation had progressed after 14 and 21 days further in the upper indifference area than in the contact and fissure healing area.

35 patients with septic postoperative complications entered a prospectively randomized study. The clinical state of these patients was daily determined using the sepsis score described by Elebute and Stoner. Endotoxin and antithrombin III were measured in the plasma using the limulus-amoebocyte-lysat test for endotoxin determination. The septic patients were treated with an immunoglobulin preparation (Pentaglobin) administered by the intravenous route. This preparation is enriched in IgM and IgA. Due to the immunoglobulin therapy the endotoxin titres decreased; simultaneously a reduction of mortality and shortening of time of hospitalization and of mechanical ventilation were observed.

In normal and pathological testicular tissue the influence of various fixing agents (Formalin solution, Bouins solution, Hellys solution, Carnoys solution) concerning the acoustical properties of testicular tissue was examined. By means of an ultrasound spectroscopic measurement technique the ultrasound damping was registered by calculation of the ultrasound damping coefficient alpha. The results show that the most lower alpha values were obtained by fixation with formalin solution as well in normal as in altered testicular tissue. The results of fixation according to Helly, Carnoy and Bouin did show markedly differences. Therefore, the fixation of testicular tissue using formalin solution is the best way for experimental examinations of the ultrasound damping behaviour.

We studied two new techniques for orthotopic preservation of the spleen in an animal model with respect to their technical feasibility and their hemostatic efficacy. This study was performed in two stages. In the first, the treatment of central bursting ruptures by splenorrhaphy using a resorbable compressive mesh was tested. 20 sheep have been used for this part of the study. They were divided into four groups (A: control, B: sham operation, C: splenectomy, D: mesh splenorrhaphy). Following completion of this stage, two animals from group A and two from group B were used to test a second experimental setting. Experimental trauma corresponding to isolated third degree polar rupture of the spleen was induced. This was then treated by a polar resection using stapling instruments. All animals from each stage were subjected to spleen scanning three months postoperatively, followed by splenectomy. The spleens were then examined histologically. Both macroscopically and microscopically normal splenic tissue was found. No difference between the different groups could be detected by laboratory investigations. Gamma-globulins and total serum proteins were within normal ranges after five weeks. Splenic scan revealed an excellent function of the pulp. Both techniques are distinguished by their facility and rapidity, as well as reliable hemostasis and minimal technical prerequisites.