1,720,961 research outputs found
Observational study on the use of remifentanil in general anesthesia. Drug utilisation research.
No full textAIM: The use of remifentanil in routine clinical practice during the induction and maintenance of general anesthesia as well as the quality of awakening after anesthesia and post-operative pain management have been assessed.
METHODS: A total of 123 Italian anesthetists were involved; data of 1 295 patients (ASA I-IV) undergoing surgical interventions (range duration of intervention 30-240 min), in which remifentanil was used according to internal anesthesiologic procedures, have been collected. The most common modality of anesthesia induction is to use a syringe pump to start remifentanil administration. The remifentanil dosage mainly used to start the infusion was 0.2 mg/kg/min (29.2% of patients), as well as at the beginning of maintenance of anesthesia (35.1%).
RESULTS: During maintenance of anesthesia, 36% of surgical interventions did not need changes of remifentanil infusion rate, whereas in the rest of the intervention 1 to 4 changes were done. The induction of anesthesia is predominantly intravenous with concomitant use of propofol and TPS, whereas the agents most frequently used during maintenance were sevoflurane (49.8%), nitrous oxide (43.7%) and propofol (35.2%). Awakening was mainly judged rapid in 93% of interventions; the postoperative pain at awakening was judged nil in 61% of cases and severe in 1.5%. The administration of analgesic treatment mainly started prior to the end of intervention (70% cases).
CONCLUSION: This Drug Utilisation Research study demonstrated that the use of remifentanil according to its peculiar pharmacological profile, such as potent opioid with rapid onset and offset of action, the synergistic effect with propofol and the right management of post-operative pain are widely consolidated in Italian clinical practice
Cisatracurium versus vecuronium: a comparative, double blind, randomized, multicenter study in adult patients under propofol/fentanyl/N2O anesthesia.
No full textThe aim of this study was to compare the time course characteristics of cisatracurium (C) and vecuronium (V) induced neuromuscular block (NMB) following multiple doses, allowing spontaneous complete recovery (SCRT) and evaluating the influence of age.
Methods. Following institutional approval and signed informed consent, 177 adult ASA 1-2 patients were included in a randomized, double-blind, multicenter study under N20/02/fentanyl/propofol anesthesia. Muscle relaxation was induced with 0.15 mg/kg C or 0.l mg/kg V and was maintained with 0.03 mg/kg of C or 0.02 mg/kg of V injected at T1 25% recovery. Intubating conditions were assessed at 2 min after the initial dose. Time course of NMB was monitored using accelerography (Tofguard) of the adductor pollicis with train-of-four (TOF). Data were analyzed with parametric (Anova) and non parametric statistics (χ2, Kruskal Wallis).
Results. Both drugs offered good/excellent intubating conditions: duration of action of NMB (mean values ± SD, minutes) were: dur25 first dose: V 38.20±13.2 vs C 51.5±11.3 (Por< 65 no differences were noted in the intervals studied following C, while all were longer following V. The duration of block of C was longer than V; the SCRT after the final dose of C was shorter than V albeit not significant. There was a clinically significant increase in duration of block and recovery time in elderly patients for V but not for C.
Conclusion. C and V allow predictable NMB duration and spontaneous recovery even if administered in multiple repeated doses; but in elderly patients duration of block and recovery time is longer following Vecuroniu
Remifentanil vs fentanyl with a target controlled propofol infusion in patients undergoing craniotomy for supratentorial lesions.
No full textPerioperative handling of patients on antiplatelet therapy with need for surgery.
No full textThe widespread use of metal stents and drug-eluting stents has shown the extent to which patients with unstable coronary perfusion depend on antiplatelet drugs, and how their risk of late thrombosis depends on the long-term use of agents such as clopidogrel. It has also been shown that the risk of surgical bleeding, if antiplatelet drugs are continued, is lower than that of coronary thrombosis if they are withdrawn. Thus, except for low-risk settings, the practice of withdrawing antiplatelet drugs 5-10 days prior to surgical procedures should be changed. The following suggestions are meant to provide a guideline in this respect. Most of the current surgical procedures may be performed while on low-dose aspirin treatment. Except when bleeding may occur in closed spaces (e.g. intracranial surgery, spinal surgery in the medullary canal, surgery of the posterior chamber of the eye) or where excessive blood loss is expected, where only clopidogrel should be discontinued; in all other cases the surgical procedures should be carried out in the presence of dual antiplatelet agents (if prescribed). Aspirin may be discontinued only in subjects at low risk of thrombosis, and at high risk of intraoperative bleeding. Operations associated with an expected excessive blood loss should be postponed unless vital. When prescribed for acute coronary syndrome or during stent re-endothelialization, clopidogrel should not be discontinued before a noncardiac procedure. For elective procedures, surgery should be postponed until the end of the indication for clopidogrel. After the operation, clopidogrel should be resumed within the 12-24 h. Cardiac procedures should be postponed for at least 4 days after clopidogrel withdrawal. The thrombotic risk of preoperative withdrawal of antiplatelet drugs overwhelms the benefit of regional or neuraxial blockade. Antiplatelet treatment replacement by heparin or low-molecular weight heparin does not provide protection against the risk of coronary artery or stent thrombosis. Haemostasis requires that at least 20% of circulating platelets have a normal function. As the effects of antiplatelet agents are not reversible by other drugs, fresh platelets are the only manner to rapidly restore normal haemostasis. Aprotinin decreases postoperative bleeding and transfusion rates in patients undergoing CABG and on clopidogrel during the days preceding surgery
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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