1,720,967 research outputs found
Impact evaluation of two different general anesthesia protocols (TIVA with propofol vs isoflurane) on the total number of interventions to treat cardiovascular depression or arousal/movement episodes in dogs undergoing orthopedic surgery receiving an intrathecal anesthesia
Full text linkThe aim of this prospective, randomized clinical trial was to compare the total number of anesthetic interventions (TNAI) performed by the anesthetist to treat cardiovascular depression or arousal/movement episodes in dogs receiving intrathecal and general anesthesia (GA), maintained using propofol-based TIVA (group P) or isoflurane (group I). Mean arterial pressure (MAP) before (T0) and 12 min after intrathecal anesthesia (T1) and intraoperative vasoactive consumption were also compared. The TNAI to deepen the anesthetic plane or to treat hemodynamic depression in the pre-surgical and intra-surgical period was calculated in forty-two client-owned dogs randomly assigned to group P or I. Ten dogs for each group complied with the inclusion criteria and were analyzed. In pre-surgical period, the TNAI was higher in Group I [2 (0-5)] than Group P [0 (0-2)] (P=0.022), and ephedrine consumption was also higher in Group I [75 (0-200) μg/kg)] than Group P [(0 (0-50)] (P=0.016). MAP (mmHg) in Group P was 79 (66-95) at T0 and 65 (59-86) at T1 and 67.5 (50-73) and 57 (53-66) in Group I, respectively. At T0 and T1, MAP was higher in Group P (P=0.005 and P=0.006, respectively). No differences were found between the two groups in the intrasurgical period (P>0.05). This study shows that the GA protocol can have a relevant impact on the TNAI performed by the anesthetist in the pre-surgical period of anesthesia, to treat cardiovascular depression or arousal/movement episodes in dogs receiving intrathecal anesthesia
Correlation of the ratio of caudal vena cava diameter and aorta diameter with systolic pressure variation in anesthetized dogs
No full textOBJECTIVE To evaluate the correlation coefficient of the ratio between diameter of the caudal vena cava (CVC) and diameter of the aorta (Ao) in dogs as determined ultrasonographically with systolic pressure variation (SPV). ANIMALS 14 client-owned dogs (9 females and 5 males; mean ± SD age, 73 ± 40 months; mean body weight, 22 ± 7 kg) that underwent anesthesia for repair of skin wounds. PROCEDURES Anesthesia was induced. Controlled mechanical ventilation with a peak inspiratory pressure of 8 cm H2O was immediately started, and SPV was measured. During a brief period of suspension of ventilation, CVC-to-Ao ratio was measured on a transverse right-lateral intercostal ultrasonographic image obtained at the level of the porta hepatis. When the SPV was ≥ 4 mm Hg, at least 1 bolus (3 to 4 mL/kg) of Hartmann solution was administered IV during a 1-minute period. Bolus administration was stopped and the CVC-to-Ao ratio measured when SPV was < 4 mm Hg. Correlation coefficient analysis was perfo..
Can transit-time flow measurement improve graft patency and clinical outcome in patients undergoing coronary artery bypass grafting?
No full textA best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was if transit-time flow measurement (TTFM) can improve graft patency and clinical outcome in patients undergoing coronary surgery. Altogether 102 papers were found using the reported search, of which 10 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The papers considered for the analysis focus attention on three major topics: intraoperative graft verification with the aim of improving immediate graft patency; predictive power of early-and mid-term graft patency and clinical outcome. Among TTFM parameters, according to different authors, mean graft flow is set at 10 or 15 ml/min; pulsatility index is set at three or five; insufficiency ratio is set by 3 or 4%. We conclude that TTFM is a reliable method to verify intraoperative graft patency. There is some evidence that checking graft patency intraoperatively may improve mid-term outcomes
The incidence of spontaneous movements (myoclonus) in dogs undergoing total intravenous anaesthesia with propofol
No full textAbsolute and relative risk prediction in patients candidate to isolated aortic valve replacement: should we change our mind?
No full textObjective: The European System for Cardiac Operative Risk Evaluation (EuroSCORE) calculator performance in 30-day outcome prediction after isolated aortic valve replacement (AVR) was evaluated to assess its absolute reliability and usefulness as selection criteria to percutaneous aortic valve implantation (PAVI). Methods: We carried out a retrospective statistical analysis on 379 patients (group 0) consecutively submitted to isolated AVR in the past 10 years of surgical activity. We discriminated two periods of 5 years each, so we considered two subgroups of patients: group 1 (200 patients operated during 1999-2003); group 2 (179 patients operated during 2004-2008). We used receiver operating characteristics (ROC) curves for discriminatory power analysis. Model calibration was evaluated with the Hosmer-Lemeshow goodness-of-fit test and Pseudo R-2 analysis. Results: The overall expected mortality rate at the logistic calculator was 9.37% compared with an observed 10-year mortality of 5.2% (p = 0.006). Absolute risk prediction in group 1 fitted the observed outcome (p = 0.24) while expected mortality in group 2 was significantly higher than observed (p=0.005). Applying threshold values used as PAVI selection criteria (logistic EuroSCORE >20 or >15), against 29% and 24.3% expected mortality rate, respectively, we registered a significant difference in the observed values (11.4%, p = 0.022; 8.6%, p = 0.005, respectively). The Hosmer-Lemeshow test demonstrated a lack of model fit in the overall group (p = 0.019). ROC analysis revealed a sufficient discriminatory power for either total population (logistic area under curve (AUROC) 0.706; 95% confidence interval (CI): 0.604-0.809; p = 0.002) and group 1 (logistic AUROC 0.752; 95% CI: 0.643-0.860; p = 0.002). Group 2 showed a lack of risk stratification (logistic AUROC 0.613; 95% CI: 0.401-0.824; p = 0.348). Conclusions: EuroSCORE appears to be an invalid model in absolute and relative risk prediction for isolated AVR. On this basis, its use in selecting candidates to PAVI should be carefully weighted. Correct stratification and sufficient calibration of absolute risk estimate of high-risk patients are, therefore, mandatory in the aim of assigning those patients who show risk factors really responsible for the worst surgical outcome to new techniques. The goal should be reached by exploring the weight of each independent predictor of death in each single institution involved in PAVI procedures, evaluating local surgical results in terms of absolute risk and analysing those variables significantly affecting relative risk. (C) 2009 European Association for Cardio-Thoracic Surgery
Comparison of epidural versus intrathecal anaesthesia in dogs undergoing pelvic limb orthopaedic surgery
Full text linkOBJECTIVE:
To compare the procedural failure rate (PFR), intraoperative rescue analgesia (iRA) probability and postoperative duration of motor block after epidural and intrathecal anaesthesia in dogs undergoing pelvic limb orthopaedic surgery.
STUDY DESIGN:
Prospective, randomized clinical trial.
ANIMALS:
Ninety-two client-owned dogs.
METHODS:
Dogs were assigned randomly to receive either lumbosacral epidural anaesthesia (EA) (bupivacaine 0.5% and morphine 1%) or intrathecal anaesthesia with the same drugs in a hyperbaric solution (HIA). Inaccurate positioning of the needle, assessed by radiographic imaging, and lack of cerebral spinal fluid outflow were considered procedural failures (PFs) of EA and HIA, respectively. Fentanyl (1 μg kg(-1) IV) was provided for intraoperative rescue analgesia, when either the heart rate or the mean arterial pressure increased by 30% above the pre-stimulation value. Its use was recorded as a sign of intraoperative analgesic failure. The motor block resolution was evaluated postoperatively. Variables were compared using Fisher's exact test, the Mann-Whitney U test and the Kaplan-Meier 'survival' analysis as relevant.
RESULTS:
The PFRs in the EA and HIA groups were 15/47 (32%) and 3/45 (7%), respectively (p = 0.003). Differences in iRA were analysed in 26 and 30 subjects in the EA and HIA groups respectively, using Kaplan-Meier survival analysis. The iRA probability within the first 80 minutes of needle injection (NI) was higher in the EA group (p = 0.045). The incidence of dogs walking within 3 hours of NI was significantly higher in the HIA group (8/20, 40%) than in the EA group (0/17) (p = 0.004).
CONCLUSIONS AND CLINICAL RELEVANCE:
HIA was found to have lower PF, lower intraoperative analgesic failure and faster motor block resolution. In this study HIA was shown to provide some advantages over EA in dogs undergoing commonly performed pelvic limb orthopaedic surgery in a day-hospital regime
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
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