PubMed Health⌕ Search

Biomedical subjects

D Balogh

Publications and source records attributed to D Balogh.

At least 19 recordsLinked to original sources
PubMed2000

Exogenous neopterin causes cardiac contractile dysfunction in the isolated perfused rat heart.

Neopterin is known in humans as a sensitive marker for diseases associated with increased activity of the cellular immune system. Recent studies report neopterin also to exhibit distinct effects: neopterin induces inducible nitric oxide synthase expression in rat vascular smooth muscle cells and activates translocation of nuclear factor- kappa B. Neopterin may also induce oxidative stress causing apoptotic cell death, or superinduce tumor necrosis factor- alpha -mediated apoptosis. Observing these effects in cell cultures, we were interested in possible consequences of neopterin on cardiac function in the isolated perfused rat heart. The influence of neopterin in three different concentrations (10 micromol/l, 50 micromol/l, 100 micromol/l) on cardiac contractility parameters and coronary vascular resistance were studied in 67 male Sprague-Dawley rats using the temperature-controlled and pressure-constant Langendorff apparatus with retrograde perfusion of the aorta with a Krebs-Henseleit buffer. Treatment with 100 micromol/l neopterin resulted in a significant decrease in coronary flow and cardiac contractility. Coronary flow decreased from 15.2 to 9.5 ml/min (P=0.002), left ventricular pressure from 80 to 52 mmHg (P=0. 002), rate of pressure fall from 1605 to 923 mmHg/s (P=0.001) and rate of pressure rise from 2862 to 1709 mmHg/s (P=0.001). Concentrations lower than 100 micromol/l neopterin had no significant effect on cardiac function. Our study demonstrates a considerable influence of exogenous neopterin on cardiac performance in the Langendorff model of isolated perfused rat hearts. This has to be considered a potential pathogenic factor of cardiac disturbances in diseases in which high concentrations of neopterin are released due to immune activation. At present the exact mechanism remains unclear.

Animals↗
PubMed1999

Effects of a leucocyte depleting arterial line filter on perioperative proteolytic enzyme and oxygen free radical release in patients undergoing aortocoronary bypass surgery.

BACKGROUND: Proteolytic enzymes and oxygen free radicals released from activated leucocytes contribute significantly to the organ dysfunction associated with cardiopulmonary bypass. Leucocyte depletion during extracorporeal circulation should reduce the release of these toxic compounds and thereby improve postbypass myocardial and pulmonary function. Recently, a leucocyte-specific arterial line filter to achieve leucocyte depletion during clinical perfusion has become commercially available. The aim of this study, therefore, was to evaluate the influence of the leucocyte depleting arterial line filter on proteolytic enzyme release, oxygen free radical release and postbypass pulmonary and myocardial function in patients undergoing bypass surgery. METHODS: Forty patients undergoing elective aortocoronary bypass surgery were included into this prospective, randomized clinical study, 20 in the leucocyte depletion (LG-6 group, leucocyte-specific arterial line filter) and 20 in the control group (AV-6 group, standard arterial line filter). White cell count, differential white cell count, plasma elastase concentration, plasma malondialdehyde concentration and C-reactive protein were determined before, twice during and immediately after cardiopulmonary bypass, at the end of surgery and 6 and 20 h thereafter. RESULTS: White cell count, differential white cell count, malondialdehyde and C-reactive protein were not significantly different between LG-6 and control patients. Plasma elastase concentrations were significantly (P < or = 0.03) higher during and immediately after extracorporeal circulation in LG-6 group patients. Need for inotropic support, arterial pO2 after extracorporeal circulation and perioperative CK MB mass and troponin I release were not different between the two groups of patients. CONCLUSION: The use of a leucocyte depleting arterial line filter is associated with an increased release of the proteolytic enzyme elastase, but does not reliably and consistently achieve effective leucocyte depletion during clinical perfusion. In contrast to previous studies, we could not demonstrate any significant difference in postbypass pulmonary or myocardial function between patients perfused with the leucocyte-specific arterial line filter and control patients. Our data do not support the routine use of a leucocyte depleting arterial line filter during clinical perfusion in patients undergoing elective aortocoronary bypass surgery.

Aged↗
PubMed1999

National publication output in medical research.

OBJECTIVE: Both the total number of publications and the number of publications in high-ranking journals determine a country's reputation in scientific research. A predominance of national authors in a country's international high-ranking journals has occasionally been presumed. We therefore analysed the publication output of various countries and the proportion of national authors in international high-ranking journals. METHODS: The database EMBASE (Excerpta Medica) by means of the online service Dialog was used to analyse the national publication output of various countries during the years 1986 to 1990 and 1991 to 1995 and the proportion of national authors in The Lancet and The New England Journal of Medicine (NEJM.). RESULTS: American and British publications played the leading roles in the total number of medical publications from 1986 to 1990 (35.6% and 8.8%, respectively) and also from 1991 to 1995 (34.3% and 9.1%, respectively). A more detailed analysis revealed an unexpectedly high national publication output (publications per million inhabitants) of smaller countries, which exceeded that of larger nations during both periods studied (national publication output 1986-90 vs. 1991-95: Israel: (3386 vs. 3447), Sweden: (3303 vs. 3620), Switzerland: (2930 vs. 3722), Denmark: (2884 vs. 3167), UK: (2186 vs. 2825), USA: (2042 vs. 2388)). Furthermore, the proportion of national authors during both periods (1986-90 vs. 1991-95) studied was 41.8% vs. 34.1% in the case of The Lancet and 77.9% vs. 69.5% in the case of The New England Journal of Medicine. CONCLUSIONS: The present study found an unexpectedly high national publication output of smaller countries as well as a clearly disproportionate number of published articles from national authors in The Lancet and the NEJM during the years 1986 to 1990 and 1991 to 1995.

Databases as Topic↗
PubMed1998

[Comparative study of propofol emulsions for anesthesia in varicose vein operations].

PURPOSE: It is commonly known that propofol-based anaesthesia is easily controlled and well tolerated. These advantages of propofol are partly offset by the comparably high costs of the anaesthetic. The present prospective randomised double-blind cross-over study compared two propofol emulsions with regard to their efficacy and drug safety. METHODS: 30 patients were included in this study. All patients underwent two propofol-based anaesthesias for leg vein surgery on both legs within 2-4 days. The patients were randomised in two treatment groups where Group A (n = 15) received the investigational drug for the 2nd anaesthesia and the control drug for the 1st anaesthesia. The order of drug application was reversed for Group B (n = 15). The propofol induction doses, the maintenance doses, and the side effect profiles were evaluated for the purpose of comparing the two propofol emulsions. RESULTS: The study showed no differences in the efficacy of the two propofol emulsions. Furthermore, the side effect profiles were almost identical and did not reveal any unknown side effects of propofol. CONCLUSIONS: The results clearly demonstrate that both propofol emulsions are comparably well suited for vascular surgery anaesthesia. This study demonstrates a methodological clinical approach to compare the same medication supplied by different manufacturers.

Adult↗
PubMed1997

Augmented release of brain natriuretic peptide during reperfusion of the human heart after cardioplegic cardiac arrest.

The aim of the study was to investigate the release of natriuretic peptides during myocardial ischaemia and reperfusion associated with cardioplegic cardiac arrest. Brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) concentrations were measured in paired arterial, central venous and coronary sinus blood samples in 19 patients undergoing elective coronary artery bypass grafting before aortic crossclamping and 1, 5, 10 and 20 min after aortic declamping. Peak myocardial BNP release after aortic declamping was significantly higher than baseline values before aortic crossclamping. Both peak and cumulative BNP release during reperfusion correlated significantly with the severity of ischaemia, as assessed by myocardial lactate production. In 3 patients with perioperative myocardial ischaemia, cumulative and peak myocardial BNP release after aortic unclamping was markedly higher than in the remaining 16 uneventful patients. Myocardial ANP release during reperfusion was not significantly different from baseline values before aortic crossclamping. In conclusion, our data demonstrate a significantly enhanced myocardial BNP release early during reperfusion of the human heart after global ischaemia associated with cardioplegic cardiac arrest.

Adult↗
PubMed1997

Inhalation injury treated with extracorporeal CO2 elimination.

A 38-year-old male was admitted to the intensive care unit with a full-thickness burn involving 30 per cent of his total body surface area (TBSA) and severe inhalation injury. Respiratory failure developed within 54 h and CO2 could not be eliminated, even by very invasive mechanical ventilation. Because of the patient's age and the minor extent of the burned TBSA, we started extracorporeal CO2 elimination (ECCO2-R) and continued ECCO2-R for 30 days, when the patient was weaned from ECC. The clinical course during ECCO2-R was complicated by major bleeding from a thoracotomy tube, from the site of tangential excision and by four septic episodes. Lung biopsy was performed twice on day 29 (during ECCO2-R) and day 58 (after ECCO2-R) after admission and revealed bronchiolitis obliterans without tendency to recovery. The patient died of sepsis with multiorgan failure on day 81 after trauma.

Adult↗
PubMed1996

Percutaneous venoarterial extracorporeal membrane oxygenation for emergency mechanical circulatory support.

In this retrospective study we report our initial experience with percutaneous venoarterial extracorporeal membrane oxygenation in the emergency treatment of intractable cardiogenic shock or pulseless electrical activity. Between January 1994 and July 1995, percutaneous venoarterial extracorporeal membrane oxygenation was attempted in seven patients (pulseless electrical activity, five patients; cardiogenic shock, two patients). In two of the seven patients, efforts at arterial cannulation resulted in cannula perforation at the level of the iliac artery. In the remaining five patients, percutaneous venoarterial extracorporeal membrane oxygenation could be established and was maintained for 3-84 h. Major bleeding remained a common complication during extracorporeal membrane oxygenation despite the use of heparin-coated bypass circuits and was responsible for death during extracorporeal membrane oxygenation in one patient. The remaining four patients could be weaned from mechanical circulatory support within 24 h, two after surgical interventions (resection of right atrial tumor, heart transplantation), one after thrombolytic therapy. In one patient, cardiac function recovered spontaneously after 6 h on venoarterial extracorporeal membrane oxygenation. Three patients were discharged from hospital, two of them made a full recovery, one sustained severe hypoxic brain injury. A few patients with intractable cardiogenic shock or pulseless electrical activity can be resuscitated with the help of emergency percutaneous venoarterial extracorporeal membrane oxygenation. Emergency venoarterial extracorporeal membrane oxygenation is associated with a high rate of complications and its use should therefore be limited to selected patients with a rapidly correctable underlying cardiopulmonary pathology (anatomic, metabolic or hypothermic) who do not respond to conventional advanced cardiac life support.

Emergencies↗
PubMed1995

[Intraoperative calorimetry in aortic bifurcation reconstruction].

Oxygen uptake (VO2) and carbon dioxide elimination (VCO2) can be measured with an indirect calorimeter, this method is well established in routine monitoring of ICU patients to evaluate metabolic state as a reflection of stress. In various experimental studies it was demonstrated that anaesthetics can influence whole-body metabolism. The purpose of this study was to examine whether indirect calorimetry can be used intraoperatively during routine anaesthesia and whether presumable changes in metabolism can be detected immediately. Abdominal aortic cross-clamping changes circulation, nutritional supply of the lower extremities and thus VO2 and VCO2. We therefore used this operation for our study. METHOD. Eleven patients, mean age 64 years, undergoing reconstruction of the aortic bifurcation, were studied. After premedication with piritramid and atropine, total intravenous anaesthesia (TIVA) was performed with fentanyl and midazolam after an induction with thiopental. Patients were ventilated with a Servo-Ventilator 900 D and a constant FiO2 of 0.5, without N2O. Routine monitoring consisted of ECG, pulsoximetry, CVP and continuous AP. VO2 and VCO2 were measured with a Deltatrac (Datex), and data were registered every minute. For statistical evaluation we used a Wilcoxon-Ranksum test for matched pairs, p < 0.05 was considered significant. Data from specific time (5 min after intubation, 5 min before clamping; 5, 10 and 15 min after clamping, before declamping and 5 and 10 min after declamping and at the end of surgery) were calculated. In addition to absolute values, we compared the measured VO2 and VCO2 to baseline (5 min before clamping = MP2). RESULTS. Mean operating time was 139 min +/- 37; aortic cross-clamping time for the first extremity was 38 min and 55 min for the second. As expected, there was a significant decrease in VO2 (90% of baseline) and VCO2 (75% of baseline) during aortic cross-clamping. After declamping VO2 again rose to 110% of baseline, or to 103% for the second limb. VCO2 increased to only 90% and 82%, respectively. At the end of surgery VO2 reached baseline, whereas VCO2 remains at 83%. The respiratory quotient VCO2: VO2 was markedly reduced from 0.95 +/- 0.156 to 0.73 +/- 0.06 during surgery. The Deltatrac showed every change in VO2 without delay; changes in VCO2 seem to occur somewhat retarded. DISCUSSION. Aortic cross-clamping leads to a marked decrease in VO2 and VCO2 reflecting the temporary reduction in whole-body metabolism. Declamping results in a compensatory rise, especially in VO2. VCO2 seems to increase less after declamping, perhaps due to the CO2 pool of the organism or to a change in metabolism from carbohydrate to mainly fat oxidation. The results of this study demonstrate that indirect calorimetry can easily be performed during anaesthesia and surgery. Preconditions are a non-rebreathing system without airleak, constant FiO2 < 0.6 and no use of nitrous oxide.

Aged↗
PubMed1995

Reperfusion after cardioplegic cardiac arrest--effects on intracoronary leucocyte elastase release and oxygen free radical mediated lipid peroxidation.

In experimental animal models reperfusion of ischaemic myocardium causes sequestration of leucocytes within the coronary circulation. Leucocytes contribute to postischaemic myocardial injury by releasing proteolytic enzymes and by generating oxygen free radicals. The aim of this study was to investigate whether leucocytes also contribute to myocardial injury following ischaemia and reperfusion associated with cardioplegic cardiac arrest. Therefore, we studied the release of the proteolytic enzyme elastase and oxygen free radical initiated myocardial lipid peroxidation in coronary sinus blood during reperfusion after cardioplegic cardiac arrest. The elastase-alpha-1-proteinase inhibitor complex and malondialdehyde (a byproduct of myocardial lipid peroxidation) were measured in arterial, central venous and coronary sinus blood samples in 19 patients undergoing elective coronary artery bypass grafting before aortic crossclamping and 1, 5, 10 and 20 m in after aortic declamping. Malondialdehyde concentrations did not increase significantly during the study period, whereas elastase concentrations showed a significant increase during cardiopulmonary bypass in arterial, central venous as well as coronary sinus blood. Neither elastase nor malondialdehyde concentrations in coronary sinus blood differed significantly from arterial or central venous blood at any time point measured. Our data demonstrated increased elastase concentrations during cardiopulmonary bypass, but we did not find enhance intracoronary elastase release or myocardial during cardiopulmonary bypass, but we did not find enhanced intracoronary elastase release or myocardial lipid peroxidation. Our data suggest that patients are sufficiently protected from leucocyte mediated ischaemia reperfusion injury during uncomplicated coronary artery bypass grafting with cardioplegic arrest.

Adult↗
PubMed1995

Coronary sinus endothelin-1 concentrations after cardioplegic cardiac arrest.

BACKGROUND: Data from animal experiments demonstrate that endothelin-1 is released into the coronary circulation during myocardial ischaemia and reperfusion, indicating that endothelin-1 may contribute to the pathophysiology of ischaemia and reperfusion. The aim of this study was to investigate the release of endothelin-1 into the coronary circulation during reperfusion of the human heart after hypothermic cardioplegic cardiac arrest. METHODS: Endothelin-1 was measured in arterial, central venous and coronary sinus blood in 19 patients undergoing elective uncomplicated coronary artery bypass grafting before aortic crossclamping and 1, 5, 10 and 20 min after aortic declamping. RESULTS: Endothelin-1 concentrations showed a slight non-significant increase over baseline values 1, 5, 10 and 20 min after aortic declamping. Endothelin-1 concentrations were not significantly higher in coronary sinus blood than in arterial blood at any time point measured, indicating no net release of endothelin-1 by the heart. CONCLUSIONS: Our results did not demonstrate endothelin-1 release into the coronary circulation after myocardial ischemia and reperfusion associated with hypothermic cardioplegic cardiac arrest.

Adult↗
PubMed1994

Prognostic markers in patients with severe accidental hypothermia and cardiocirculatory arrest.

The aim of this retrospective study was to investigate whether plasma potassium, pH and activated clotting time (ACT), obtained from a central venous blood sample immediately after admission to hospital, could predict outcome in patients with severe accidental hypothermia and cardiocirculatory arrest. Twenty-two patients rewarmed with cardiopulmonary bypass were studied retrospectively (12 patients after avalanche accidents, seven patients after cold water submersion and three patients after prolonged exposure to cold). In 12 patients stable spontaneous circulation could not be restored. In 10 patients stable spontaneous circulation could be restored. Two of these 10 patients survived long-term. Plasma potassium, central venous pH and ACT were clinically useful prognostic markers in hypothermic arrest victims after avalanche accidents: a plasma potassium value exceeding 9 mmol/l, a pH equal to or less than 6.50 or an ACT exceeding 400 s was seen in patients in whom spontaneous circulation could not be restored. Plasma potassium, central venous pH and ACT were of only limited prognostic value in hypothermic arrest victims following cold water submersion or prolonged exposure to cold. In hypothermic arrest victims after cold water submersion a central venous pH as low as 6.51 on admission did not exclude long-term survival. Moderate and severe hyperkalemia in arrest victims after prolonged exposure to cold need not necessarily indicate postmortem autolysis. A decision to continue or terminate resuscitation cannot be based on laboratory parameters. Nevertheless, our data suggest that plasma potassium, central venous pH and ACT on admission can be used to identify hypothermic arrest victims in whom death preceded cooling. If several hypothermic arrest victims are admitted simultaneously after avalanche accidents, these 3 parameters can help not to waste limited cardiopulmonary bypass facilities for patients with no hope of survival.

Adolescent↗
PubMed1994

Glycogen phosphorylase isoenzyme BB mass release after coronary artery bypass grafting.

Glycogen phosphorylase isoenzyme BB mass release was studied in 20 patients undergoing coronary artery bypass grafting. In 16 patients with uneventful coronary artery bypass grafting, glycogen phosphorylase isoenzyme BB mass concentrations showed a significant, transient increase in the post cross-clamping period and decreased to baseline values within 20 hours (peak concentrations ranged from 12.7 micrograms/l to 47.5 micrograms/l, median 40 micrograms/l). One patient did not fulfil criteria for perioperative myocardial infarction, but clinical data indicated myocardial injury after aortic unclamping. In this patient only glycogen phosphorylase isoenzyme BB mass concentration and not creatine kinase isoenzyme MB catalytic concentration was increased, compared with uneventful patients. In 2 patients with emergency coronary artery bypass grafting for evolving myocardial infarction, glycogen phosphorylase isoenzyme BB mass concentrations, but not creatine kinase isoenzyme MB catalytic concentrations, correlated with clinical evidence of myocardial ischaemia. Our data indicate that glycogen phosphorylase isoenzyme BB mass concentration is a very sensitive laboratory marker of perioperative myocardial injury in patients undergoing coronary artery bypass grafting.

Aged↗