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S Svensson

Publications and source records attributed to S Svensson.

At least 73 records · Page 4Linked to original sources
PubMed1994

Glucose-insulin-potassium (GIK) prevents derangement of myocardial metabolism in brain-dead pigs.

Brain death is associated with neuroendocrine changes resulting in reduced myocardial glycogen content. The purpose of this study was to investigate the effects of glucose-insulin-potassium (GIK), on myocardial metabolism in brain-dead pigs. Sixteen brain-dead pigs were given GIK infusion (n = 8), or Ringer solution (n = 8). At end-point (7 h post brain death) arterial concentrations and myocardial arteriovenous (a-v) concentration differences of glucose, lactate and free fatty acids (FFA) were assessed, and myocardial biopsy specimens were taken from the right atrium and left ventricle. Biopsies were also taken from five normal pigs. Myocardial glycogen content in the GIK group was significantly higher compared to the control group, but comparable to the non-brain-dead animals. There was a higher and significant myocardial uptake of glucose and lactate in the GIK group compared to the controls. Plasma levels of FFA were significantly lower in the GIK group, and the myocardial uptake of FFA was 5 times higher in the control group compared to the GIK group. There were no significant differences in hemodynamic variables among the groups. In conclusion, intravenous supply of GIK to brain-dead pigs results in increased myocardial glycogen content and seems to prevent abnormal myocardial metabolism, which may have clinical implications for the myocardial protection of donor hearts.

Animals↗
PubMed1994

Coacute heparin: a new simple monotest for monitoring heparin treatment.

Anti-Factor Xa methods have been generally accepted for the monitoring of heparin treatment, mainly due to their sensitivity to LMW heparin and excellent performance on automated equipment. When such equipment is not available, as in small laboratories or on the night shift, there is a need for a simple manual method. In the present method activated Factor X and a chromogenic peptide substrate are colyophilized in plastic cuvettes under conditions that avoid reaction between the two constituents. The assay is performed accordingly: Plasma (200 microL) is diluted in 3.0 mL predispensed Tris buffer containing dextran sulfate 8000 to avoid losses of heparin due to, for example, platelet factor 4. The diluted plasma (400 microL) is added to a cuvette. The reagents are rapidly dissolved and the reactions start. The rate of Factor Xa inhibition is proportional to the heparin activity. During the incubation, the substrate is also hydrolyzed by the remaining enzyme. This combination of reactions is insensitive to changes in temperature, making it possible to perform the assay at room temperature. After 10 minutes incubation, the reaction is stopped by adding 400 microL of 5% acetic acid. The absorbance is read in a well-calibrated photometer and the results plotted on a graph available in the kit. Eleven commercially available heparins have been tested with the assay and they all fell within a narrow range, showing the relevance of using a standard plot for all heparins. The LMW heparins behaved differently and it may also be that they demand different therapeutic strategies.

Antithrombins↗
PubMed1993

Coacute heparin: a new simple monotest for monitoring heparin treatment.

Anti-factor Xa methods have been generally accepted for the monitoring of heparin treatment mainly due to their sensitivity to LMWH and excellent performance on automated equipment. When such equipment is not available, as in small laboratories or on the night shift, there is a need for a simple manual method. In the present method, activated Factor X and a chromogenic peptide substrate are colyophilized in plastic cuvettes under conditions that avoid reaction between the two constituents. The assay is performed accordingly. Plasma (200 microliters) is diluted in 3.0 ml predispensed Tris buffer containing dextran sulfate 8000 to avoid losses of heparin due to platelet factor 4, for example. The diluted plasma (400 microliters) is added to a cuvette. The reagents are rapidly dissolved and the reactions start. The rate of Factor Xa inhibition is proportional to the heparin activity. During the incubation, the substrate is also hydrolyzed by the remaining enzyme. This combination of reactions is insensitive to changes in temperature making it possible to perform the assay at room temperature. After 10 minutes incubation, the reaction is stopped by adding 400 microliters of 5% acetic acid. The absorbance is read in a well-calibrated photometer and the results plotted on a graph available in the kit. Eleven commercially available heparins have been tested with the assay and they all fell within a narrow range, showing the relevance of using a standard plot for all heparins. The LMWH behaved differently and it may also be that they demand different therapeutic strategies.

Amino Acid Sequence↗
PubMed1992

Effects of insulin on myocardial uptake of branched chain amino acids soon after cardiac operations.

Infusion of insulin-glucose-potassium is used to support the failing heart after cardiac operations. Although the effects on myocardial uptake of carbohydrates and lipids have been described, the effects on myocardial extraction of amino acids are unknown. This study was undertaken to clarify the effect of insulin-glucose-potassium on the pattern of amino acid uptake/release in myocardial and skeletal muscle after coronary operations. The amino acid uptake/release of the heart and of the leg was studied in 18 patients 1 hour after coronary bypass operations. The patients were randomized to treatment with 25 U of fast-acting insulin as a bolus injection followed by a continuous infusion of 1 U/kg body weight for 1 hour, or to serve as control patients. The hyperinsulinemic "clamp" technique was used to keep blood glucose unchanged during the study. In the insulin-treated group, the arterial concentration of 17 of 22 individual amino acids, including the three branched chain amino acids, decreased, the remainder being unchanged. The amino acid uptake/release of the leg was unchanged. The net myocardial uptake of leucine and isoleucine shifted to a no-uptake/no-release in the insulin-treated group, whereas the no-uptake/no-release of tyrosine and phenylalanine turned into a significant release. A positive correlation was observed between arterial concentration and myocardial uptake/release of the three branched chain amino acids. It is suggested that insulin, by lowering the arterial concentration of leucine and isoleucine, inhibited the myocardial uptake of these amino acids. This may have a negative effect on postoperative myocardial protein balance suggested by the release of tyrosine and phenylalanine.

Amino Acids, Branched-Chain↗
PubMed1991

[Heart transplantation in Denmark. Therapeutic routines and preliminary results].

When the criterion of brain-death was introduced in Denmark on 1.7.1990, the possibility for heart transplantation and other interventions was opened. The first heart transplantation was carried out 3.10.1990 and, during the first year, 28 transplantations were carried out on 27 patients. The therapeutic routines in the department are reviewed and the results obtained after the first year are presented. A total of 33 donors who fulfilled the donor criteria were available. Of these, 28 came to Rigshospitalet, two were sent abroad and suitable recipients could not be found for two. The recipient group consisted of four women and 23 men with an average of 46 years. At the time of writing, on an average 169 days after operation (13-330), 23 out of 27 patients survived in good health and with normal cardiac function. Three patients are still in hospital.

Adult↗