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Inflation Pressure (inflation + pressure)
Selected AbstractsNurses' knowledge of error in blood pressure measurement techniqueINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 3 2002BHScArticle first published online: 27 MAY 200, DipAppSci(NsgEdn), Robin S Armstrong RN Errors in measuring blood pressure may have significant impact on the investigation and treatment of patients. Errors arise from faults in measurement technique or the equipment used. In Australia, blood pressure measurement technique is taught to nurses during their undergraduate education and may not be reviewed again. This observational, descriptive study surveyed clinical nurses at a metropolitan teaching hospital at shift hand-over time. Participation was voluntary and anonymous by 78 nurses who answered a questionnaire to determine the need and focus for updating blood pressure measurement technique. Sixty-one per cent of participants conformed to currently accepted practice in identifying systolic blood pressure, and 71% diastolic blood pressure; 54% correctly interpreted a description of blood pressure sounds containing an auscultatory gap. Correct answers for assessment of faulty equipment were given by 58%, assessing cuff size by 57%, arm position for seated measurement by 14%, determination of inflation pressure by 29% and deflation rate 62%. Incidence of terminal digit preference was 32%. These findings indicate that knowledge of participants was inadequate to perform blood pressure measurement in a standardized manner, and prevent introduced error. [source] Analyse Expérimentale et Numérique du Comportement de Membranes Thermoplastiques en ABS et en HIPS dans le Procédé de ThermoformageTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2005Fouad Erchiqui Abstract Dans cet article nous nous intéresserons, d'une part à la caractérisation biaxiale, en soufflage libre du comportement des membranes thermoplastiques circulaires en ABS et en HIPS et, d'autre part à la simulation numérique de la mise en forme d'une pièce creuse en ABS et en HIPS. Les modèles de comportement hyperélastique de Mooney-Rivlin et d'Ogden sont considérés. Dans un premier temps nous utilisons la méthode des différences finies à pas variables pour la résolution du problème d'équilibre de la membrane et un algorithme modifié de Levenberg-Marquardt pour minimiser la différence entre la pression calculée et celle mesurée. Ceci permet l'identification des constantes matérielles incorporées dans les modèles utilisés. Pour la modélisation numérique par la méthode dynamique des éléments finis, nous considérons une formulation lagrangienne, l'hypothèse de la théorie des membranes et une charge en pression, découlant de la loi des gaz parfaits, pour étudier l'influence des lois de comportements sur la distribution finale des épaisseurs et des contraintes dans une pièce thermoformée en ABS et en HIPS. In this work, we are interested, on the one hand in the characterization of circular polymeric ABS and HIPS membrane under biaxial deformation using the bubble inflation technique, on the other hand in modelling and numerical simulation of the thermoforming of ABS and HIPS materials using the dynamic finite element method. Hyperelastic models (Mooney-Rivlin, Ogden) are considered. First, the governing equations for the inflation of a flat circular membrane are solved using a variable-step-size-finite difference method and a modified Levenberg-Marquardt algorithm to minimize the difference between the calculated and measured inflation pressure. This will determine the material constants embedded within the models used. For numerical simulation, the lagrangian formulation together with the assumption of the membrane theory is used. Moreover, the influence of the hyperalastic model on the thickness and on the stress distribution in the thermoforming sheet are analysed for ABS and HIPS materials. [source] Nociceptin/orphanin FQ inhibits capsaicin-induced guinea-pig airway contraction through an inward-rectifier potassium channelBRITISH JOURNAL OF PHARMACOLOGY, Issue 3 2002Yanlin Jia Nociceptin/orphanin FQ (N/OFQ), an endogenous opioid-like orphan receptor (NOP receptor, previously termed ORL1 receptor) agonist, has been found to inhibit capsaicin-induced bronchoconstriction in isolated guinea-pig lungs and in vivo. The underlying mechanisms are not clear. In the present studies, we tested the effect of N/OFQ on VR1 channel function in isolated guinea-pig nodose ganglia cells. Capsaicin increased intracellular Ca2+ concentration in these cells through activation of vanilloid receptors. Capsaicin-induced Ca2+ responses were attenuated by pretreatment of nodose neurons with N/OFQ (1 ,M). N/OFQ inhibitory effect on the Ca2+ response in nodose ganglia cells was antagonized by tertiapin (0.5 ,M), an inhibitor of inward-rectifier K+ channels, but not by verapamil, a voltage gated Ca2+ channel blocker, indicating that an inward-rectifier K+ channel is involved in N/OFQ inhibitory effect. In isolated guinea-pig bronchus, N/OFQ (1 ,M) inhibited capsaicin-induced airway contraction. Tertiapin (0.5 ,M) abolished the N/OFQ inhibition of capsaicin-induced bronchial contraction. Capsaicin (10 ,g) increased pulmonary inflation pressure in the isolated perfused guinea-pig lungs. This response was significantly attenuated by pretreatment with N/OFQ (1 ,M). Tertiapin also abolished the N/OFQ inhibitory effect on capsaicin-induced bronchoconstriction in perfused lungs. Capsaicin increased the release of substance P and neurokinin A from isolated lungs. N/OFQ (1 ,M) blocked the capsaicin-induced tachykinin release. These results indicate that N/OFQ-induced hyperpolarization of tachykinin containing airway sensory nerves, through an inward-rectifier K+ channel activation, accounts for the inhibition of capsaicin-evoked broncoconstriction. British Journal of Pharmacology (2002) 135, 764,770; doi:10.1038/sj.bjp.0704515 [source] Clinical assessment of a new real time 3D quantitative coronary angiography system: Evaluation in stented vessel segmentsCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2006Rainer Gradaus MD Abstract Background: Foreshortening is a recognized problem that is present in angiography and results from views that are not perpendicular to coronary lesions. This limits visual coronary analysis as well as 2D quantitative coronary angiography systems (QCA). The CardiOp-B System® is a 3D image acquisition and processing software system designed as an add-on to conventional X-ray angiography system. CardiOp-B's features include real time and off line analysis with comprehensive 3D reconstruction integrating all of the available information of two 2D vessel angiographies into one 3D image. It was the aim of the study to analyze the accuracy of this new 3D QCA system. Methods: 3D QCA was performed in 50 patients (age 64 ± 10.9; 84% male; LV-EF 63 ± 16%) measuring 61 stents during high-pressure inflation (diameter: 2.25,4 mm; length: 8,32 mm). The obtained values (proximal and distal stent diameter, stent length) were correlated with the predefined size of the stents at the used inflation pressure. Results: The linear correlation for the proximal stent diameter was Stentprox= 0.03 + 0.93 × real stent size (r2 = 0.85). The linear correlation for the distal stent diameter was Stentdistal= ,0.03 + 0.89 × real stent size (r2 = 0.81). The linear correlation for the stent length was Stentlength= ,0.61 + 1.02 × real stent length (r2 = 0.98). Conclusions: The CardiOp-B System® is a new 3D QCA system with a high linear correlation between the real vessel size and the obtained vessel dimension. It provides real time or off line accurate and comprehensive diagnostic information to the interventional cardiologist without changing the basic coronary angiography procedure. © 2006 Wiley-Liss, Inc. [source] Immediate and late clinical and angiographic outcomes after GFX coronary stenting: Is high-pressure balloon dilatation necessary?CLINICAL CARDIOLOGY, Issue 8 2000Ph.D., Seong-Wook Park M.D. Abstract Background: The GFX stent is a balloon-expandable stent made of sinusoidal element of stainless steel. The adjunct high-pressure balloon dilatations were usually recommended in routine stenting procedure. Hypothesis: The aim of this study was to evaluate the immediate and long-term clinical and angiographic outcomes and to investigate the necessity of high-pressure balloon dilatation during GFX stenting. Methods: In all, 172 consecutive patients underwent single 12 or 18 mm GFX stent implantation in 188 native coronary lesions. Two types of stenting technique were used: (1) stent size of a final stent-to-artery ratio of 1:1 (inflation pressure > 10 atm, high-pressure group), and (2) stent size of 0.5 mm bigger than reference vessel (inflation pressure , 10 atm, low-pressure group). The adjunct high-pressure balloon dilatations were performed only in cases of suboptimal results. Results: The adjunct high-pressure balloon dilatation was required in 11 of 83 lesions (13%) in the high-pressure group and in 7 of 105 lesions (7%) in the low-pressure group (p = 0.203). Procedural success rate was 100%. There were no significant differences of in-hospital and long-term clinical events between the two groups. The overall angiographic restenosis rate was 17.7%; 18.4% in the high-pressure group and 17.1% in the low-pressure group (p = 0.991). Conclusions: The GFX stent is a safe and effective device with a high procedural success rate and favorable late clinical outcome for treatment of native coronary artery disease. Further randomized trials may be needed to compare stenting techniques in GFX stent implantation. [source] Airway closure in anesthetized infants and children: influence of inspiratory pressures and volumesACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2002A. Thorsteinsson Background: Cyclic opening and closing of lung units during tidal breathing may be an important cause of iatrogenic lung injury. We hypothesized that airway closure is uncommon in children with healthy lungs when inspiratory pressures are kept low, but paradoxically may occur when inspiratory pressures are increased. Methods: Elastic equilibrium volume (EEV) and closing capacity (CC) were measured with a tracer gas (SF6) technique in 11 anesthetized, muscle-relaxed, endotracheally intubated and artificially ventilated healthy children, aged 0.6,13 years. Airway closing was studied in a randomized order at two inflation pressures, +20 or +30 cmH2O, and CC and CC/EEV were calculated from the plots obtained when the lungs were exsufflated to ,20 cmH2O. (CC/EEV >1 indicates that airway closure might occur during tidal breathing). Furthermore, a measure of uneven ventilation, multiple breath alveolar mixing efficiency (MBAME), was obtained. Results: Airway closure within the tidal volume (CC/EEV >1) was observed in four and eight children (not significant, NS) after 20 and 30 cmH2O inflation, respectively. However, CC30/EEV was >CC20/EEV in all children (P,0.001). The MBAME was 75±7% (normal) and did not correlate with CC/EEV. Conclusion: Airway closure within tidal volumes may occur in artificially ventilated healthy children during ventilation with low inspiratory pressure. However, the risk of airway closure and thus opening within the tidal volume increases when the inspiratory pressures are increased. [source] CAN TUNISIA MOVE TO INFLATION TARGETING?THE DEVELOPING ECONOMIES, Issue 1 2007Adel BOUGHRARA E47; E52; E58 Inflation targeting has become an alternative monetary strategy that has been followed by many industrial and emerging countries. This study considers whether the adoption of inflation targeting would be relevant for Tunisia. More specifically, this paper aims at checking whether the necessary conditions for the successful implementation of such a strategy are fulfilled or not. It is found that fiscal dominance does not constitute the main hindrance to the adoption of inflation targeting. Other impediments have been identified, especially a weak financial system in general, the unsound and fragile banking system in particular, and the glaring lack of knowledge about the monetary transmission mechanism. Furthermore, it has been pointed out that if Tunisian monetary authorities continue to carry out the present exchange rate regime, namely, the constant real exchange rate rule, an inflation targeting regime will not be sufficient to properly contain the inflation pressures caused by demand shocks. [source] | ||||||||||