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
    Notfall + Rettungsmedizin 1 (1998), S. 5-12 
    ISSN: 1436-0578
    Keywords: Schlüsselwörter Ethik ; Rettungsdienst ; Notfallmedizin ; Futility ; Prävention ; Key words Ethics ; Emergency medical services ; Emergency medicine ; Futility ; Prevention
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract Health care in emergencies is a social good and a hallmark of a humane society, the ethical foundations of which have to form the basis of all decisions regarding medical emergencies. The ethics of emergency medical care are part of general medical ethics. Their principles are outlined and put into perspective with regard to dilemmas characteristic of emergency care. Due to dwindling resources, the efficiency of emergency medical care is being increasingly scrutinized. Possibilities of rationalizing care without compromising its quality are being discussed, such as renouncing futile therapy and implementing measures of prevention. If emergency medical services are to accomplish their mission, however, observing standards of medical practice, legal provisions, and the given framework of society, they must not surrender to pure cost containment.
    Notes: Zusammenfassung Gesundheitsfürsorge in Notfällen ist ein soziales Gut und Ausdruck der Humanität einer Gesellschaft. Ihr ethisches Grundwerteverständnis muß allen notfallmedizinischen Entscheidungen zugrundeliegen. Rettungsdienstliche Ethik ist Teil einer allgemeinen medizinischen Ethik, deren Grundlagen umrissen und deren Entscheidungs- und Handlungsanweisungen anhand rettungsdienstlicher Dilemmata geprüft werden. Da der Rettungsdienst aufgrund sich verknappender Ressourcen zunehmend unter wirtschaftlichen Rechtfertigungsdruck gerät, werden als Möglichkeiten zur Rationalisierung ohne Qualitätseinbuße die Abgrenzung nichtiger Maßnahmen („futile therapy”) und die Prävention diskutiert. Soll der Rettungsdienst die ihm gestellten Aufgaben unter Beachtung medizinischer Richtlinien, juristischer Vorgaben und gesellschaftlicher Rahmenbedingungen erfüllen, kann er sich nicht zum Büttel marktwirtschaftlichen Controllings machen.
    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 Klinische Studien ; Klassifikation ; Notfallmedizin ; Planung ; Durchführung ; Key words Clinical trials ; Classification ; Emergency medicine ; Design ; Conduct
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract Clinical studies are usually conceived of as controlled randomized trials, as retrospective patient statistics or as single case reports. However, such a classification is too narrow and overlooks many other forms of study designs. This review, therefore, offers a more encompassing and practical classification of clinical studies for the field of emergency medicine. Randomized controlled trials fulfill scientific criteria at the highest level (gold standard): comparison, repeatability, objective measurement. At the same time, randomized trials also have to comply with demanding ethical criteria and must be justifiable in the individual patient. Therefore, comparable uncertainty with regard to the superiority of the treatment options under investigation is a sine qua non. In addition to randomized trials, six other groups of clinical trials have the potential to solve scientific questions in emergency medicine: observational studies, decision analysis, meta analysis, public health care studies, case reports and descriptive summary statistics and studies on ethical problems. This variability in trial designs calls for a clinically oriented methodologist; the concept and institutionalization of theoretical surgery has been a response to this demand. All study types in this review are illustrated by examples in emergency medicine. Literature for advanced reading in particular trial methodologies can be found in the reference list. A checklist summarizes all elements for designing and conducting randomized trials in emergency medicine. All clinical trials striving for a high standard of quality – whether randomized or not – depend on the following prerequisites: professional organization, time effort, a supportive social environment and a scientific culture.
    Notes: Zusammenfassung Bei klinischen Studien wird in erster Linie an kontrollierte randomisierte Studien, an retrospektive Serienberichte und an Einzelfallberichte gedacht. Diese Klassifikation ist aber viel zu eng und übersieht die vielen Möglichkeiten und Notwendigkeiten von andersartigen Studienplänen und -durchführungen. Prospektive kontrollierte randomisierte Studien sind experimentelle Studien an Patienten mit dem höchsten Anspruch an Wissenschaftlichkeit (Goldstandard), aber nur unter strengsten ethischen Prämissen: therapeutische Vertretbarkeit im Hinblick auf den jeweiligen Patienten und deshalb vergleichbare Ungewißheit für die Überlegenheit eines Verfahrens am einzelnen Patienten. Daneben gibt es sechs weitere Gruppen von Studienarten, die für die Lösung notfallmedizinischer Probleme benötigt werden, und diese Gruppen haben eine Serie von speziellen Ausprägungen. Dies macht den anwendungsorientierten klinischen Methodiker so notwendig, die Entwicklung der Theoretischen Chirurgie findet darin ihre Erklärung. Für jede Studienart werden in dieser Übersicht Beipiele aus der Notfallmedizin und Literaturstellen angegeben, wo das methodische Rüstzeug für die speziellen Studienausprägungen zu finden ist. Eine Checkliste für die Planung einer randomisierten kontrollierten Studie schließt die Arbeit ab, zusammen mit dem Beispiel der Mainz-Marburg Studie zum perioperativen Risiko. Alle klinischen Studien mit Qualität, nicht nur die kontrollierten randomisierten Studien, verlangen eine professionelle Organisation, Zeit sowie ein soziales Umfeld und eine Studienkultur, die solche wissenschaftlichen Leistungen gedeihen lassen.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-2013
    Keywords: Capillary diameter ; Oxygen tension ; Reduction of perfusion pressure ; Intravital microscopy ; Recoil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract When perfusion pressure is reduced, red blood cell flow in the capillaries of skeletal muscle ceases at a positive pressure difference across the vascular bed, while arterioles dilate and venules are not constricted. This flow cessation (i.e., cessation of red blood cell flow) and luminal diameter changes in capillaries following femoral arterial pressure reduction were investigated in the rabbit tenuissimus muscle in situ (n=42) using intravital video microscopy. Arterial pressure was reduced by occlusion of the aorta distal to the renal arteries. During the experiments, leg and muscle were placed in a sealed box. The muscle was exposed to low PO2 by leading a gas mixture deprived of O2 through the box. Locally at the muscle surface, i.e., under the microscope objective, PO2 was varied by varying the PO2 in the superfusion solution. In all experiments, the remainder of the muscle was kept at low (〈 20 mm Hg) PO2. The incidence of flow cessation was virtually zero at low local (〈 20 mm Hg) PO2 and became almost 100% at local values above 70 mm Hg. Initial equivalent capillary diameters were 3.1–5.8 μm (median 4.0 μm) and did not correlate with local O2 tension. During aorta occlusion, capillary diameters significantly (P 〈 0.0001) decreased by a median value of 8% at all local PO2 values; in 14 out of 54 capillaries local diameter became less than 2.8 μm. The extent of diameter reduction did not correlate with PO2. In the 14 capillaries in which the diameter became less than 2.8 μm flow cessation occurred in only four cases. The minimal diameter reached was always at the site of an endothelial nucleus. The capillary diameter reductions are probably due to passive recoil. In the 48 capillaries in which flow ceased, only in four cases did a red blood cell stop at the site of the nucleus. We conclude that capillary diameter reductions (local and generalized) lead to a considerable increase in capillary resistance which contributes to the occurrence of flow cessation but cannot solely explain it.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-2013
    Keywords: Acridine red ; Dextrans ; Fluorescence ; Intravital microscopy ; Microcirculation ; Platelets ; Rheology ; Rabbit mesentery
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Dextrans bind to the surface of platelets, red blood cells and endothelium. We investigated whether a low doses (30 mg/kg IV) of 40-kDa (Dx40), neutral, 500-kDa (Dx500) or sulphated, 500-kDa (Dx500S) dextrans influence platelet distribution in rabbit mesenteric arterioles and venules (diameter 17–33 μm). Intravital fluorescence videomicroscopy was used to visualize platelets labelled in vivo with acridine red. Their concentration distribution determined within a thin optical section about the median vessel plane was expressed relative to the mean concentration in that vessel. In arterioles, Dx500 and Dx500S increased the relative platelet concentration in the centre [radial position (R): 0.0–0.47 R] from 0.60 to 1.07 (P〈0.001) and 1.20 (P〈0.003), and reduced it near the wall (0.8–0.9 R) from 1.59 to 0.93 (P〈0.02) and 0.95 (P〈0.03) respectively. In venules a similar, but non-significant, effect was observed. Dx40 did not change platelet distribution in arterioles, but decreased their concentration in venules in the centre from 1.08 to 0.71 (P〈0.03) and increased it at the wall from 0.89 to 1.27 (P〈0.04). The deformability of red blood cells was unchanged, but their aggregation tendency increased approximately twofold after Dx500 and Dx500S injection, while Dx40 had no influence. Leucocyte margination in venules did not affect platelet distribution. Dextran injection did not change microvascular flow velocity or plasma viscosity, suggesting that the observed changes in arteriolar platelet distribution were caused by binding of dextran to the surface of platelets and/or red blood cells.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-2013
    Keywords: Intravital microscopy ; Resistance regulation ; Tenuissimus muscle ; Skeletal muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Changes in vasomotion parameters and their consequences for local arteriolar resistance were studied in transverse arterioles and their first order side branches in the tenuissimus muscle of 10 young urethane anesthetized rabbits during stepwise reduction of arterial pressure, using intravital microscopy. To assess the influence of vasomotion on mean local arteriolar resistance, the effective vascular diameter, as a measure of mean flow carrying capacity, was calculated. The contribution of vasomotion to the mean local resistance is limited in transverse arterioles, but important in first order side branches, dominating the flow fluctuations in the downstream capillaries. During pressure reduction, an over-all increase in vasomotion cycle length and amplitude was found in both transverse arterioles and first order side branches, concomitant with an increase in effective arteriolar diameter and a decrease in local blood flow and reduced velocity, as a measure of wall shear rate. Flow autoregulation was observed in 70% of the arterioles. The changes in cycle length and amplitude showed only limited correlations with local blood flow, reduced velocity, arterial pressure and effective arteriolar diameter. This indicates that it is unlikely that only one of these variables is responsible for the changes in the vasomotion parameters.
    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...