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
    ISSN: 1432-1238
    Keywords: Critical illness ; Hemodynamics ; Circulation ; Vasoactive substances ; Endothelin ; Catecholamines ; Atrial natriuretic peptide ; Outcome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Objective Regulation of circulatory homeostasis is based on several factors including various circulating vasoactive substances. Whether these regulators differ between survivors and non-survivors was investigated in critically ill patients. Design Prospective study. Setting Clinical investigation on a surgical intensive care unit of an university hospital. Patients 60 consecutive patients suffering from trauma (n=21) or postoperative complications (n=39) were studied prospectively. The patients were divided into survivors (n=27) and non-survivors (n=33). Therapy was adjusted to the standards of modern intensive care management by physicians who were not involved in the study. Measurements and results Endothelin-1, atrial natriuretic peptide (ANP), vasopressin, renin, and catecholamine (epinephrine, norepinephrine) plasma levels were measured from arterial blood samples using radioimmunoassay (RIA) or high-pressure liquid chromatography (HPLC) technique on the day of admission to ICU and during the following 5 days. Various hemodynamic parameters were also monitored during that period. The non-survivors showed elevated pulmonary artery pressure (PAP: 34.1±5.4 mmHg) and pulmonary capillary wedge pressure (PCWP: 20.3±7.3 mmHg) already at the beginning of the study. Cardiac index (CI) did not differ among the groups, whereas right ventricular ejection fraction (RVEF) decreased in the non-survivors. PaO2/FIO2 decreased only in the non-survivors, whereas VO2 increased in the survivors (from 246±48 to 331±43 ml/min). Plasma levels of renin (from 206±40 to 595±81 pg/ml) and vasopressin (from 5.78±0.82 to 7.97±0.69 pg/ml) increased significantly in the non-survivors. Epinephrine and norepinephrine plasma concentrations were elevated in the non-survivors already at baseline and tremendously increased in these patients during the following days. ANP plasma levels significantly increased also only in the non-survivors (from 188±63 to 339±55 pg/ml) (p〈0.05). Endothelin-1 decreased in the survivors, whereas it significantly increased in the non-survivors (from 3.62±0.68 to 9.37±0.94 pg/ml) during the study period (p〈0.05). Analyses of co-variance revealed overall no significant correlation between circulating vasoactive substances and hemodynamics. Conclusions Systemic and regional regulators of the circulation were markedly changed by critical illness. In survivors, these regulators almost normalized within the study period of 5 days, whereas in non-survivors these alterations were even aggravated. It can only be speculated whether these regulator systems were influenced by activation of various mediator systems or whether they themselves influenced the negative outcome in the non-survivors.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Psychopharmacology 43 (1975), S. 229-232 
    ISSN: 1432-2072
    Keywords: LSD ; Discriminable Properties of Drugs ; Serotonin Receptors ; Rats
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Rats were initially trained to discriminate LSD from saline in two-lever operant chambers by reinforcing responses only on one lever following intraperitoneal injections of 80 Μg/ kg of LSD and only on the other lever following saline injections. Choice responding during extinction periods (no water reinforcement for either response) indicated a high level of discriminability (95% correct) following either LSD or saline. A dose-response curve for LSD, obtained by tests for lever choice after injections of 10, 20, 30, 40, 50, and 60 Μg/kg, indicated that 10 Μg/kg produced only 30% responding on the LSD lever. This percentage was increased (to 83%) by reinforcing responding on the LSD lever following injections of 10 Μg/kg. Subsequent tests indicated that doses of 5.0 and 2.5 Μg/kg produced a majority of responses on the LSD lever. Since at these low doses LSD has few measurable biochemical or behavioral effects, we hypothesize that the discriminable cue of LSD is related to direct stimulation of central serotonergic receptors.
    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...