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H D Pauer

Publications and source records attributed to H D Pauer.

13 recordsLinked to original sources

[Ischemia, hypothermia, length of death-perfusion and temperature related factors for preservation of organs].

In order to guarantee the comparability of the results of the various working teams and experimental conditions within the preservation of organs, above all of the preservation of kidneys, it is referred to the importance which belongs to the clear establishment of the used notions, such as time of hyperthermy (duration), time of ischaemia and dead time (warm and cold). For the practice of kidney taking simple time determinations between two steps of taking have made their way. The warm dead time is the duration between clamping of the renal vessels and the beginning of the flow with cold preservation solution. This establishment is justified by the standardised conditions of taking. For reserach these pauschal temporary data are not sufficient and the exact establishment of the notion used is necessary.

Animals

[Storage behavior of Collins' solution under various conditions].

It is reported on examinations of the precipitation reactions in the Collins solution. The solution which is produced in three and two compartments, respectively, has been given together and stored under three different conditions. During a period of 48 hours the electrolytes sodium and potassium and the pH-value were controlled. Hereby significant differences of these values are shown in the various kinds of compilation as well as between the three- and the two-compartment solution. No or only slight precipitations in the closed system are observed at 20 and 40 degrees C in contrast to the open system.

Drug Storage

[Behavior of the renal perfusion resistance during automatic organ preservation].

It is reported on experimental investigations in the preservation of mini pig kidneys. At first the behaviour during the initial hypothermic gravitation perfusion is examined. From the relation of perfusate outflow to the perfusate inflow the perfusion quotient PQ is calculated. It is a measure for the volume storage developing during the perfusion (tissue oedema?) and significantly correlates with the warm dead time. The behaviour of the renal current resistance during the following machine permanent perfusion was examined with the help of KABI-albumin-solution and Collins-solution with 5% dextran M 40, and Collins-solution with 5% dextran M 75. Here was shown that the increase of the current resistance correlates with the preservation time depending on the PQ of the initial perfusion. The result is a typical behaviour for the individual solutions. We are of the opinion that the judgement of the behaviour of the kidneys during the machine perfusion must be seen in connection with the initial perfusion.

Animals

[Determination of intrapulmonary shunt in acute lung failure and during therapy by means of extracorporeal oxygenation (author's transl)].

The reasons for the especial importance of acute lung failure within the framework of intensive medicine are elaborated. In most cases acute lung failure can be successfully treated by timely ventilation and support for the heart-function. If conventional therapy fails, extracorporeal long-term oxygenation by means of a membrane oxygenator can be a successful technique, provided that a very critical indication is available. The magnitude of the intrapulmonary right-left shunt S is an important parameter for the assessment of the extent of acute lung failure and its prognosis, and also in the establishment of the indication for the use of extracorporeal oxygenation and the therapeutic process. The derivation of simple extended shunt equations for any form of extracorporeal oxygenation is possible on the basis of measurements of blood-flow and oxygen transport. This represents an important contribution to the mathematical description of a therapeutic technique.

Biological Transport

[Temperature measurements and course in a kidney preservation unit].

It is reported on two models of organ containers in which the course of the temperature was measured and registered on different conditions. The principle of construction used allowed the resignation of a special isolation. The results show that behaviour and course of the temperature in the organ containers meet all requirements.

Kidney

[Design and construction of a kidney preservation unit (Laboratory Models LM 1 and LM 2) and its components].

By combination of the adequate construction elements (cryostate, warmth exchanger, roll pump) the laboratory model of unit for the preservation of kidneys for animal experimental investigations was established. For this purpose a special organ container made of piacryl was constructed in two models, which with double walls does not need a particular isolation and, therefore, is freely accessible for manipulations during the experiment. Measurings of the horizontal and vertical distribution of the temperature in the organ container resulted in a decrease of temperature of 5--6 degrees (single bottom of the container) or 1--2 degrees (double chilled bottom of the container). The report of the courses of temperature during an organ perfusion resulted in a constancy of the average temperature of 6--8 degrees. The kidney preservation unit has proved in a long-term experiment during 24 hours.

Animals

[Multiple organic replacement in intensive care medicine seen from anaesthesiological view (author's transl)].

Additional effective methods have to be studied for in order to improve further the treatment of life threatening conditions which are accompanied by reversible breakdown of organic functions. The development and the recent state of different technical and biological replacement functions are presented and their advantages and disadvantages are described. Temporary multiple organic replacement (lung, kidney, liver) by way of peripheral vessels offers a therapeutic procedure capable of development. This procedure is based on the knowledge that in different endogenous and exogenous intoxications, and also after shock symptomatology generally, several vital functions are simultaneously disturbed or become acutely insufficient. This coincidental breakdown requires a simultaneous, effective, multilateral therapy. First partial successes by means of equipment for multiple organic replacement are critically analysed and conclusions for further improvement of its function are discussed.

Artificial Organs

[Experimental coronary stenoses and occlusions].

A constrictor for experimentally inducing stenoses and obstructions of the coronary artery is described. Smallness, good adaptability to every vascular diameter, atraumatic insertion, and slow swelling are its advantages. Within 12 months a coronary artery could be constricted by two thirds. In one third of the cases the lumen was narrowed by more than 75 per cent. Just 50 per cent of the cases showed chronic infarction after coronary obstruction, the other half developed differently marked myocardiac fibrosis. At high-degree narrowing of the arteries, 75 per cent of the cases showed disseminated myocardiac fibrosis. The occlusion of the vessel is caused by constrictor, by fibroplastic alteration of the vascular wall, and by thrombosis. Different degrees of myocardiac ischemia are sequelae of different development of collaterals. The constrictor may be used for studies on the development of collaterals as well as on therapeutic measures in chronic ischemia of the myocardium.

Animals

[Studies on the functional ability of swine liver perfused with human blood in machine recirculation attempt. Experiment design, elimination of indocyanine green, galactose, bilirubin and ammonia, synthesis of urea, bile secretion].

In 11 machine experiments of recirculation the abilities of survival and functioning of livers of dwarf pigs perfused with human preserved blood were tested with the help of the eliminations of indocyanine green, galactose, bilirubin and ammonia from a closed circulation. Further urea-nitrogen were measured as indicator of the urea synthesis and bile secretion. The perfusion of the animal livers was carried out in 9 cases only through the portal vein. The values of the blood flow were between 0.4 and 1.0ml pro g liver tissue and minute in portal pressure values about 15 cm water column. Two recirculations were carried out with additional flow through the hepatic artery with about 1/5 of the whole blood flow. The results of the experiments described prove a pretty good functional performance of the perfused with human blood livers of dwarf pigs during several hours. The different animal livers, however, showed at the beginning as well as during the further course of the perfusion clear differences concerning their functional capacity. Decrease of the blood flow values below 0.5 ml pro g liver tissue lead to functional loss. The additional flow through the hepatic artery yielded no better results, compared with the only perfusion of the animal liver through the portal vein.

Ammonia

[Studies on the functional ability of swine liver perfused with human blood in machine recirculation attempt. 2. Behavior of serochemical parameters].

In the present paper is reported on the behavior of different serochemical parameters in heterologous perfusion of the liver of pigs. The perfusion of the animal livers was carried out with preserved human blood in 11 recirculation experiments (closed machine circulations). In addition to this an empty circulation with human blood without attachment to an animal liver was carried out, whereby otherwise the arrangement of the experiment was the same, in order to take into consideration the effects of the blood traumatisation in the interpretation of the results. The enzymes GOT and LAP proved as sensible indicators of the lesion of the liver cells occurring in the perfusion of the liver of the pigs. The behavior of the mitochondrial GDH as well as of the lysosomal enzymes SP and BETA-GC which scarcely increased during the recirculations in the perfusate blood, however, allows the conclusion that there did not appear a severe lesion of the liver cells (necrobiosis) during several hours of perfusion. A cholestasis did not develop during the perfusions, when one takes as basis the behavior of the enzymes AP, GGTP and AAP indicating cholestasis. Compared with GOT the enzyme GPT showed by far less elevations in the perfusate blood so that with increasing duration of the perfusion the De-Ritis-quotient significantly increased. Increased LDH-activities above all revealed the increasing during perfusion haemolysis and less reliably a lesion of the liver of the pig. The increase of ADA in the perfusate blood proved as nearly exclusively conditioned by haemolysis. Total protein, albumins, immunoglobulins, cholinesterase and thymol turbidity test remained unchanged in the course of the perfusions.

Acid Phosphatase

[Simultaneous extra-corporeal oxygenation and haemodialysis in intesive medicine (a case report) (author's transl)].

In the field of intensive care there is a rise in the number of patients with distrubed or defunct vital functions, in whom multilateral therapy on traditional lines fails. The necessity of introducing new forms of treatment has been the occasion for the development of a universal perfusion device for temporary artificial multiple-organ substitution in the Faculty of Medicine at the Martin Luther University Halle-Wittenberg. This apparatus makes possible the substitution of, or support for, the functions of lungs, kidneys and liver singly or combined, via the extracorporeal treatment of the blood. The shortterm use of the apparatus is intended to provide, in addition to functional substitution of the organs, the best possible conditions for the regeneration of damaged organs. A critical account is given of the clinical application of the apparatus.

Acute Kidney Injury

[Metabolic changes and assessment of kidney function after supercooling of the free-prepared kidney in animal experiment].

Aside from immunological problems, successful renal transplantation depends on preservation, properly maintaining its vitality and functional efficiency, also after transplantation. Complete restitution, slight functional less, reversible and irreversible renal failure, occurred according to chosen temperatures in the experiments. The best results were obtained at temperatures between 0 and +5 degrees C., mainly at an average value of +3C degrees. Irreparable renal damages developed at temperatures between 0 and -3 degrees C.

Acid-Base Equilibrium

[Experimental and clinical use of the mini-size bubble-bag thermooxygenator by the Rygg-Kyvsgaard method].

The authors report on experimental and clinical use of the Mini-size-bubble-bag-thermooxygenator according to Rygg-Kyvsgaard. The advantages and possible applications are demonstrated. The Mini-size-bubble-bag-thermooxygenator is recommended for routine cardiosurgery on infants. The authors point at possibilities to use it in systems of extracorporeal circulation beyond cardiac surgery.

Adult