Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Der Anaesthesist 46 (1997), S. S120 
    ISSN: 1432-055X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Zusammenfassung Akuter Schmerz kann schädliche Wirkungen auf beinahe jedes Organsystem im Körper ausüben. Störungen des respiratorischen, kardiovaskulären und neuroendokrinen Systems sind unmittelbar erkennbar. Nicht sofort erkennbar sind Veränderungen in der Genexpression von Neuropeptiden, Zytokinen, Wachstumsfaktoren, u.a. Diese können zu Störungen führen, die später einsetzen und länger andauern. Interaktionen zwischen dem Immun- und Nervensystem tragen gleichermaßen zur Entstehung wie auch zur Kontrolle des Entzündungsschmerzes bei. Ein Gewebstrauma triggert eine Kaskade an lokalen Vorgängen, die in einer erhöhten Sensibilität und Schmerzhaftigkeit resultieren. Etwa zur gleichen Zeit werden Mechanismen aktiviert, die dieser Entwicklung entgegenwirken. Sie führen durch zentrale wie auch lokale Wirkungen von endogenen Opioidpeptiden zu einer zunehmenden Inhibition des Entzündungsschmerzes. Der Übergang von akutem in chronischen Schmerz hängt möglicherweise einerseits von Störungen dieser intrinsischen Kontrollmechanismen, andererseits von dem rechtzeitigen Einsetzen wirkungsvoller Therapiemaßnahmen ab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-055X
    Keywords: Schlüsselwörter Lokalanästhetika: Bupivacain ; Toxizität: Lokalanästhetika ; Key words Anaesthetics ; local ; Bupivacaine ; Cerebroventricular perfusion ; Toxicity: local anaesthetics ; CNS effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract Objectives: The cardiotoxic properties of bupivacain have been well documented under in-vitro, as well as under in-vivio conditions. A further mechanism of cardiovascular impairment by bupivacaine via the central nervous system gained investigational interest in animal studies. The aim of our study was to demonstrate the effect of a ventriculocisternal perfusion of bupivacain on systemic hemodynamic variabels and their reversability by wash-out with mock-CSF. Methods: After obtaining animal investional commitee consent, nine anaesthetized and relaxated pigs were prepared for a ventriculocisternal perfusion (VCP). Hemodynamic data were obtained by invasive blood pressure measurements in the high and low pressure system as well as cardiac output (thermodilution technique), intracranial pressure and electrocardiogram. Systemic vascular resistance and stroke volume were calculated using standard formulas. A second group of three animals were exposed to an intravenous infusion of the same dose of bupivacain over the same period of time to rule out direct cardiac effects. After instrumentation baseline data were obtained (KO 1) under VCP with mock-CSF for 30 minutes. The mock-CSF was replaced by 0,05% bupivacaine in mock-CSF and VCP was continued with 3 ml · h–1 for 20 minutes. After adminstration of 500 µg bupivacaine data were collected (BU). The bupivacaine solution was replaced by mock-CSF and after twenty minutes hemodynamic measurement were repeated (KO2). Results: The intravenous adminstration of 500µg bupivacaine had no effect on all measured variables. VCP of the same dose resulted in significant increase in heart rate, systolic, diastolic and mean arterial blood pressures. Left and right heart filling pressures as well as systemic vascular resistance were not affected while the stroke volume decreased. After continuation of VCP with mock-CSF hemodynamic changes were reversed. Discussion: Our results demonstrate that bupivacaine initiates an indirect cardiovascular stimulating effect of a VCP with 500 µg of bupivacaine via the central nervous system. The intravenous administration of the same dose had no effect. The centrally mediated cardiovascular effect of bupivacaine was reversed by wash-out with mock-CSF. The cardiovascular stimulation observed in this animal experiment may be of clinical relevance as a potential sign of toxic effects of bupivacaine on the CNS.
    Notes: Zusammenfassung Die in vitro nachweisbaren kardiotoxischen Eigenschaften des Bupivacains sind weitgehend bekannt, eine weitere, über das Zentralnervensystem vermittelte Beeinflussung des Herzkreislaufsystems wird dagegen diskutiert. Ziel dieser Studie war es, die Auswirkungen der zentral vemittelten Bupivacainwirkung auf systemische Kreislaufparameter und deren Reversibilität durch Auswaschung mit künstlichem Liquor (m-CSF) tierexperimentell zu untersuchen. Methodik: Dazu wurden nach Genehmigung durch die Tierschutzkommission 9 anästhesierte Jungschweine für eine ventrikulozisternale Perfusion (VCP) mit insgesamt 500 µg Bupivacain in m-CSF präpariert. Die Messungen umfaßten neben invasiv registrierten Blutdrücken im kleinen und großen Kreislauf Herzzeitvolumen, intrakraniellen Druck und Elektrokardiogramm. Der periphere Widerstand und das Schlagvolumen wurden berechnet. Zusätzlich wurde drei Tieren einer Kontrollgruppe Bupivacain 500 µg zum Ausschluß einer direkt kardialen Wirkung intravenös appliziert. Nach einer Stabilisierungsphase im Anschluß an die Präparation wurden Ausgangswerte unter einer VCP mit m-CSF erhoben (KO 1). Danach wurde die VCP über 20 min mit Bupivacain in m-CSF fortgeführt und eine weitere Messung angeschlossen (BU). Die dritte Messung erfolgte nach VCP nur mit m-CSF über 20 min (KO 2). Ergebnisse: Die ventrikulo-zisternale Perfusion von 500 µg Bupivacain führte zu einem Anstieg des systolischen, diastolischen und mittleren arteriellen Bludrucks, der Herzfrequenz und des Herzzeitvolumens. Die rechts- und linksventrikulären Füllungsdrücke sowie der periphere Widerstand blieben unbeeinflußt. Das Schlagvolumen nahm signifikant ab. Mit der Auswaschung (KO 2) waren alle Kreislaufeffekte vollständig reversibel. Bei der intravenösen Infusion der gleichen Bupivacainmenge traten keine Änderungen in den gemessenen Variablen auf. Schlußfolgerungen: Nach unseren Ergebnissen führte die VCP mit 500 µg Bupivacain im Gegensatz zur intravenösen Infusion zu einer signifikanten, zentral vermittelten Kreislaufstimulation, die unter Fortführung der VCP mit m-CSF durch eine Verdünnung oder Auswaschung innerhalb von 20 min vollständig reversibel ist. Den beobachteten Kreislaufeffekten könnte für die frühzeitige Erkennung einer unerwünschten Reaktion auf Bupivacain für die klinische Routine Bedeutung zukommen.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-055X
    Keywords: Schlüsselwörter Hypotension ; Monitoring ; Elektroenzephalogramm ; Früh akustisch evozierte Potentiale (FAEP) ; Key words Hypotension ; Monitoring ; Electroencephalogram ; Brain-stem auditory evoked potentials (BAEP)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract For surgical removal of a malignant choroid melanoma, it is necessary to reduce systolic blood pressure to around 50–60 mmHg in order to prevent choroidal haemorrhages. However, blood pressure reduction is associated with the risk of cerebral ischaemia. We report a patient with a malignant choroid melanoma in whom waves I and II of the brainstem auditory evoked potentials (BAEP) disappeared during surgery under controlled arterial hypotension and hypothermia (31.1° C). The waves could be recorded again immediately after the mean arterial pressure was increased from 48 to 77 mmHg. The oesophageal temperature had dropped by 0.3° C at this time. The 2-channel electroencephalogram (EEG) showed no irregularities during this time period. A bilateral, reversible, apparently blood-pressure-dependent loss of waves I and II during arterial hypotension despite a normal EEG has to our knowledge not been previously described in the literature. The isolated loss of waves I and II with maintenance of waves III, IV, and V is unusual. The literature contains reports of acoustic neurinoma patients in whom only wave V could be recorded. This is regarded as an indication of continued impulse conduction despite the loss of waves I to IV. Others have observed a patient with temporary and reversible loss of BAEP wave I due to vasospasm of the internal auditory artery that apparently occurred during or shortly after manipulation of the internal auditory meatus. Assuming anatomic peculiarities in the blood supply to the generators of the BAEP waves, a stenosis of the basilar artery could be considered as the cause of the bilateral reversible loss of waves I and II. Another potential source could be the induced hypothermia, but this does not seem very likely because the patient's temperature was 0.3° C lower at the return of the waves than at their loss.
    Notes: Zusammenfassung Wir berichten über einen Patienten mit einem malignen Melanom der Aderhaut, bei dem es intraoperativ unter kontrollierter Hypotension und Hypothermie (31,3° C) zum Verlust der Wellen I und II der frühen akustisch evozierten Potentiale (FAEP) kam. Nach Anhebung des mittleren arteriellen Drucks von 48 auf 77 mmHg waren die FAEP-Wellen sofort wieder ableitbar, obwohl die ösophageale Temperatur um 0,3° C abgefallen war. Das ebenfalls abgeleitete 2-Kanal-Elektroenzephalogramm (EEG) zeigte im betreffenden Zeitraum keine Auffälligkeiten. Ein beidseitiger reversibler, offensichtlich blutdruckabhängiger Ausfall der Wellen I und II während Hypotension bei gleichzeitig unauffälligem EEG ist unseres Wissens bisher in der Literatur nicht beschrieben. Der isolierte Verlust der Wellen I und II bei erhaltenen Wellen III, IV und V ist ungewöhnlich. In der Literatur sind aber Patienten mit Akustikusneurinom beschrieben, bei denen nur die Welle V abgeleitet werden konnte. Ebenso ist ein Fall mit temporärem Verlust von FAEP-Welle I beschrieben. Als Ursache wird eine lokale Minderperfusion wegen Vasospasmus während Manipulationen in Strukturen des Meatus akustikus internus diskutiert. Ausgehend von anatomisch-physiologischen Besonderheiten der Blutversorgung der Generatoren der FAEP-Wellen kann eine Stenose der Arteria basilaris als Ursache für den beidseitigen reversiblen Ausfall der Wellen I und II diskutiert werden. Der Erhalt der Wellen III bis V könnte für eine retrograde Füllung der A. basilaris aus dem Stromgebiet des Circulus Willisii sprechen. Wir interpretieren den beidseitigen Ausfall der Wellen I und II als Folge der Minderperfusion des betreffenden Hirngewebes. Die gleichzeitig bestehende Hypothermie scheidet als Ursache für den temporären Verlust der Wellen I und II aus, weil die Temperatur des Patienten beim Wiederauftreten der Wellen I und II 0,3° C niedriger war als bei ihrem Verlust.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Description / Table of Contents: Contents Analytical expressions of the eddy current dispersion of the complex permeability for ferromagnetic bodies obeying the Rayleigh law and with shapes mentioned in the title are derived for low and moderate magnetic fields. They are valid in the whole frequency range. For low frequencies formulas for the real and the imaginary part of the permeability are presented, which permit the estimation of the error involved in the calculation of the power losses in the case of a simple superposition of eddy current and hysteresis losses.
    Notes: Übersicht Es werden analytische Ausdrücke der wirbelstrombedingten Dispersion der komplexen Permeabilität für ferromagnetische, dem Rayleighgesetz gehorchende Körper mit der in der Überschrift genannten Geometrie im Falle schwacher bis mäßig starker Magnetfelder abgeleitet, die für den gesamten Frequenzbereich gültig sind. Für niedrige Frequenzen werden Formeln für Real- und Imaginärteil der Permeabilität angegeben, die eine Abschätzung des Fehlers bei der Berechnung der Verlustleistung durch einfache Superposition von Wirbelstrom- und Hystereseverlusten gestatten.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Intensive care medicine 21 (1995), S. 235-237 
    ISSN: 1432-1238
    Keywords: Hypokalemia ; Potassium shift ; Catecholamine release ; Head trauma ; Beta-2-stimulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A sudden decrease of serum potassium below 2.5 mmol/l carries the risk of dangerous arrhythmias and requires immediate replacement therapy [6]. We refer to a patient with a brain stem compression after head injury, who developed a profound hypokalemia (K+=1.2 mmol/l) with life-threatening arrhythmias, probably due to a catecholamine induced intracellular potassium shift (beta-2-stimulation). Only by aggressive potassium replacement up to 80 mmol/h (610 mmol/16h) could potassium levels be increased and cardiac arrhythmias terminated. Although replacement therapy was stopped when the serum K+-level increased to 2.4 mmol/l, 3.5 h later the patient became hyperkalemic (8.1 mmol/l). This was probably due to a secondary shift of potassium from intra-to extracellular space. In patients with severe head trauma and the potential risk of excessive catecholamine release special attention must be paid to changes in potassium balance.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 15 (1993), S. 301-307 
    ISSN: 1432-0789
    Keywords: Mesofauna ; Amino sugar ; Soil micro-flora ; Beech forest ; Moder ; Lime
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary In December 1988, litter bags (mesh size: 45 and 1000 μm) were exposed in the organic layer of unlimed and limed moder soil under beech forest in the Solling area of Germany. Bags were retrieved on three sampling dates (May, September, and November 1989) and amounts (g m-2) of glucosamine and galactosamine were determined. Horizon-specific differences generally explained by far the largest part of the treatment variance. In the substrate sampled in December 1988 from the unlimed area glucosamine increased by a factor of 11.8 from the L 1 layer to the H layer and galactosamine by a factor of 15.9. With the exception of the F2 layer, the hexosamine amounts found in the limed substrate sampled in December 1988 were higher in all horizons than in the corresponding horizons sampled from the unlimed area. Exclusion of mesofauna from the 45-μm litter bags generally reduced the level of amino sugars at both sites. The difference between the two mesh sizes was most pronounced in the lowermost horizons (F2 and H) and quite small in the upper horizons. The exclusion of mesofauna significantly increased the glucosamine: galactosamine ratio in the two L layers of the unlimed soil on all sampling dates. Seasonal fluctuations suggested that the actual amino sugar content of the organic layer was essentially the function of two components, the first reflecting long-term accumulation of microbial metabo-lites, and the second reflecting short term fluctuations in the microbial colonization of various C sources together with spatial and temporal differences in the ability of the microflora to produce and to decompose hexosamines. The results of this study show that the mesofauna in the beech forest soils investigated significantly affected both the amino sugar components measured, and thus stimulated the accumulation of one of the most important N pools in forest soils.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical pharmacology 19 (1981), S. 65-71 
    ISSN: 1432-1041
    Keywords: atenolol ; haemodialysis ; renal failure ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of atenolol were determined following acute intravenous and chronic oral administration to 20 subjects with a glomerular filtration rate (GFR) between 5 and 113 ml/min. Plasma levels in a further 5 patients on haemodialysis were measured after intravenous treatment. The mean half life of elimination increased from 5.9 h in patients with normal renal function to 42.1 h in preuraemic patients (GFR 〈10 ml/min) following a single i. v. dose. The half life of elimination following chronic oral administration was not significantly different. Mean peak plasma concentrations increased from 540 ng/ml in patients with normal renal function to 1493 ng/ml in preuraemic patients following chronic oral treatment with 100 mg/day. The mean half life of elimination during a single haemodialysis treatment was 4.3 h. In patients with a GFR 〉30 ml/min the normal daily dose of atenolol should be employed, in patients with a GFR between 10 and 30 ml/min the dose should be reduced by half, and in patients with a GFR 〈10 ml/min a reduction by three quarters of the normal dose is recommended.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0942-0940
    Keywords: Chronic subdural haematoma ; surgery ; craniotomy ; clinical results ; computerized tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a retrospective study 143 chronic subdural haematomas in 120 patients were analysed. 64% of patients were 60 years or older. All haematomas were operated on by slightly enlarged burr-hole craniotomy and closed system drainage for three days postoperatively. A history of trauma was present in 63%. Most frequent symptoms in the older patients were mental changes and impaired consciousness. Postoperative mortality (within one month after surgery) was 4%. After a follow-up period of up to 2.5 years after surgery, 69% were neurologically normal, 20% had only minor complaints or slight deficits. Postoperative CT scans showed a gradual re-expansion of the compressed brain during the 2–3 weeks following haematoma removal.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0378-4363
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Archives of Biochemistry and Biophysics 122 (1967), S. 591-593 
    ISSN: 0003-9861
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...