939 resultados para Laryngeal mask


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Humans perceive the content (gist) of a scene very rapidly within about 40 ms [Castelhano and Henderson, 2008 Journal of Experimental Psychology Human Perception and Performance 43(3) 660-675]. It has also been demonstrated that colours contribute to the perception of the gist of a scene if the colours are diagnostic for the distinction of scenes (Oliva and Schyns, 2000 Cognitive Psychology 41 176-210). We presented 320 coloured photographs of 2 diagnostic (mountains and coasts) and 2 nondiagnostic colour scenes (cities and rooms), 80 per category, in a masking paradigm. The mask consisted of randomly distributed colour patches. SOA was varied between 20 and 80 ms, in steps of 20 ms and subjects had to indicate the gist of the scene (4AFC). A control condition without masking was also included. In line with previous results we have found that the gist of nondiagnostic coloured scenes is extracted within 40 ms. However, if colour comes into play, the extraction of the scene gist is prolonged by about 20 ms. A possible reason for this outcome might be that nondiagnostic colour scenes are identified by their luminance components which are processed faster than the colour information, which in turn mediates the identification of diagnostic colour scenes

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Airway management for successful ventilation by laypersons and inexperienced healthcare providers is difficult to achieve. Bag-valve mask (BVM) ventilation requires extensive training and is performed poorly. Supraglottic airway devices (SADs) have been successfully introduced to clinical resuscitation practice as an alternative. We evaluated recently introduced (i-gel™ and LMA-Supreme™) and established SADs (LMA-Unique™, LMA-ProSeal™) and BVM used by laypeople in training sessions on manikins.

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The real utilisation scenario of non-invasive ventilation (NIV) in Swiss ICUs has never been reported. Using a survey methodology, we developed a questionnaire sent to the directors of the 79 adult ICUs to identify the perceived pattern of NIV utilisation. We obtained a response rate of 62%. The overall utilisation rate for NIV was 26% of all mechanical ventilations, but we found significant differences in the utilisation rates among different linguistic areas, ranging from 20% in the German part to 48% in the French part (p <0.01). NIV was mainly indicated for the acute exacerbations of COPD (AeCOPD), acute cardiogenic pulmonary edema (ACPE) and acute respiratory failure (ARF) in selected do-not-intubate patients. In ACPE, CPAP was much less used than bi-level ventilation and was still applied in AeCOPD. The first line interface was a facial mask (81%) and the preferred type of ventilator was an ICU machine with an NIV module (69%). The perceived use of NIV is generally high in Switzerland, but regional variations are remarkable. The indications of NIV use are in accordance with international guidelines. A high percentage of units consider selected do-not-intubate conditions as an important additional indication.

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This paper examines accounting and financial reporting as ceremonial rituals. Its specific focus is upon changes in annual reporting rituals of financial services firms during periods of market crisis. Our preliminary findings suggest that several of the firms in our study may have made changes in their reporting rituals to construct alternative realities in an attempt to mask conflict, preserve stability, foster unity, and reinforce new social norms, core values, and corporate identities.

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This paper explores the politics of community making at the India-Bangladesh border by examining the public and private narratives of history and belonging in a Bangladeshi enclave-a sovereign piece of Bangladesh completely territorially surrounded by India. Drawing on framings of political society, this paper argues that understanding populations at the margins of South Asia and beyond requires attention to two processes: first, to the ways that para-legal activities are part and parcel of daily life; and second, to the strategies through which these groups construct themselves as moral communities deserving of inclusion within the state. Border communities often articulate narratives of dispossession, exceptionality, and marginalization to researchers and other visitors-narratives that are often unproblematically reproduced in academic treatments of the border. However, such articulations mask both the complicated histories and quotidian realities of border life. This paper views these articulations as political projects in and of themselves. By reading the more hidden histories of life in this border enclave, this article reconstructs the notion of borders as experienced by enclave residents themselves. It shows the ways that the politics of the India-Bangladesh border are constitutive of (and constituted by) a range of fractures and internal boundaries within the enclave. These boundaries are as central to forging community-to articulating who belongs and why-as are more public narratives that frame enclave residents as victims of confused territorial configurations. (C) 2012 Elsevier Ltd. All rights reserved.

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The vocal imitation of pitch by singing requires one to plan laryngeal movements on the basis of anticipated target pitch events. This process may rely on auditory imagery, which has been shown to activate motor planning areas. As such, we hypothesized that poor-pitch singing, although not typically associated with deficient pitch perception, may be associated with deficient auditory imagery. Participants vocally imitated simple pitch sequences by singing, discriminated pitch pairs on the basis of pitch height, and completed an auditory imagery self-report questionnaire (the Bucknell Auditory Imagery Scale). The percentage of trials participants sung in tune correlated significantly with self-reports of vividness for auditory imagery, although not with the ability to control auditory imagery. Pitch discrimination was not predicted by auditory imagery scores. The results thus support a link between auditory imagery and vocal imitation.

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The protozoan parasite Plasmodium is transmitted by female Anopheles mosquitoes and undergoes obligatory development within a parasitophorous vacuole in hepatocytes before it is released into the bloodstream. The transition to the blood stage was previously shown to involve the packaging of exoerythrocytic merozoites into membrane-surrounded vesicles, called merosomes, which are delivered directly into liver sinusoids. However, it was unclear whether the membrane of these merosomes was derived from the parasite membrane, the parasitophorous vacuole membrane or the host cell membrane. This knowledge is required to determine how phagocytes will be directed against merosomes. Here, we fluorescently label the candidate membranes and use live cell imaging to show that the merosome membrane derives from the host cell membrane. We also demonstrate that proteins in the host cell membrane are lost during merozoite liberation from the parasitophorous vacuole. Immediately after the breakdown of the parasitophorous vacuole membrane, the host cell mitochondria begin to degenerate and protein biosynthesis arrests. The intact host cell plasma membrane surrounding merosomes allows Plasmodium to mask itself from the host immune system and bypass the numerous Kupffer cells on its way into the bloodstream. This represents an effective strategy for evading host defenses before establishing a blood stage infection.

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A goat was scheduled for experimental surgery under general anesthesia. The first attempt of performing endotracheal intubation failed and provoked laryngeal spasm. After repeated succesful intubation of inhalation anesthesia was delivered in high concentrations of sevoflurane. Suddenly hypertension and tachycardia were observed, followed by foamy airway secretion and then severe airway hemorrhage. The authors hypothesize that laryngeal spasm provoked respiratory distress and pulmonary edema. The delivered high concentrations of sevoflurane probably enhanced a hyperadrenergic response, predisposing to the development of airway hemorrhage.

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After an uneventful general anesthesia, in a horse negative pressure pulmonary edema developed due to acute upper airway obstruction during the anesthetic recovery phase after colic surgery. No pathologic alteration of respiration was observed until the horse stood up and began suffocating. The horse had recovered with the nasogastric tube in situ. This, together with the postmortem diagnosis of laryngeal hemiplegia resulted in impairment of airflow through the larynx and development of pulmonary edema. Our objective is to alert clinicians about the possible hazard of recovery with an in-situ nasogastric tube.

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The development of pulmonary edema is divided in cardiogenic and non-cardiogenic. Cardiogenic edema pathogenically is caused by elevated hydrostatic pressure in the pulmonary capillaries due to left sided congestive heart failure. Non-cardiogenic pulmonary edema is categorized depending on the underlying pathogenesis in low-alveolar pressure, elevated permeability or neurogenic edema. Some important examples of causes are upper airway obstruction like in laryngeal paralysis or strangulation for low alveolar pressure, leptospirosis and ARDS for elevated permeability, and epilepsy, brain trauma and electrocution for neurogenic edema. The differentiation between cardiogenic versus non-cardiogenic genesis is not always straightforward, but most relevant, because treatment markedly differs between the two. Of further importance is the identification of the specific underlying cause in non-cardiogenic edema, not only for therapeutic but particularly for prognostic reasons. Depending on the cause the prognosis ranges from very poor to good chance of complete recovery.

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OBJECTIVE: To review the efficacy of pharmacological prevention of serious reactions to iodinated contrast media. DESIGN: Systematic review. DATA SOURCES: Systematic search (multiple databases, bibliographies, all languages, to October 2005) for randomised comparisons of pretreatment with placebo or no treatment (control) in patients receiving iodinated contrast media. Review methods Trial quality was assessed by all investigators. Information on trial design, population, interventions, and outcomes was abstracted by one investigator and cross checked by the others. Data were combined by using Peto odds ratios with 95% confidence intervals. RESULTS: Nine trials (1975-96, 10 011 adults) tested H1 antihistamines, corticosteroids, and an H1-H2 combination. No trial included exclusively patients with a history of allergic reactions. Many outcomes were not allergy related, and only a few were potentially life threatening. No reports on death, cardiopulmonary resuscitation, irreversible neurological deficit, or prolonged hospital stays were found. In two trials, 3/778 (0.4%) patients who received oral methylprednisolone 2x32 mg or intravenous prednisolone 250 mg had laryngeal oedema compared with 11/769 (1.4%) controls (odds ratio 0.31, 95% confidence interval 0.11 to 0.88). In two trials, 7/3093 (0.2%) patients who received oral methylprednisolone 2x32 mg had a composite outcome (including shock, bronchospasm, and laryngospasm) compared with 20/2178 (0.9%) controls (odds ratio 0.28, 0.13 to 0.60). In one trial, 1/196 (0.5%) patients who received intravenous clemastine 0.03 mg/kg and cimetidine 2-5 mg/kg had angio-oedema compared with 8/194 (4.1%) controls (odds ratio 0.20, 0.05 to 0.76). CONCLUSIONS: Life threatening anaphylactic reactions due to iodinated contrast media are rare. In unselected patients, the usefulness of premedication is doubtful, as a large number of patients need to receive premedication to prevent one potentially serious reaction. Data supporting the use of premedication in patients with a history of allergic reactions are lacking. Physicians who are dealing with these patients should not rely on the efficacy of premedication.

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BACKGROUND: The arterial pharmacokinetics of ketamine and norketamine enantiomers after racemic ketamine or S-ketamine i.v. administration were evaluated in seven gelding ponies in a crossover study (2-month interval). METHODS: Anaesthesia was induced with isoflurane in oxygen via a face-mask and then maintained at each pony's individual MAC. Racemic ketamine (2.2 mg kg(-1)) or S-ketamine (1.1 mg kg(-1)) was injected in the right jugular vein. Blood samples were collected from the right carotid artery before and at 1, 2, 4, 8, 16, 32, 64, and 128 min after ketamine administration. Ketamine and norketamine enantiomer plasma concentrations were determined by capillary electrophoresis. Individual R-ketamine and S-ketamine concentration vs time curves were analysed by non-linear least square regression two-compartment model analysis using PCNonlin. Plasma disposition curves for R-norketamine and S-norketamine were described by estimating AUC, C(max), and T(max). Pulse rate (PR), respiratory rate (R(f)), tidal volume (V(T)), minute volume ventilation (V(E)), end-tidal partial pressure of carbon dioxide (PE'(CO(2))), and mean arterial blood pressure (MAP) were also evaluated. RESULTS: The pharmacokinetic parameters of S- and R-ketamine administered in the racemic mixture or S-ketamine administered separately did not differ significantly. Statistically significant higher AUC and C(max) were found for S-norketamine compared with R-norketamine in the racemic group. Overall, R(f), V(E), PE'(CO(2)), and MAP were significantly higher in the racemic group, whereas PR was higher in the S-ketamine group. CONCLUSIONS: Norketamine enantiomers showed different pharmacokinetic profiles after single i.v. administration of racemic ketamine in ponies anaesthetised with isoflurane in oxygen (1 MAC). Cardiopulmonary variables require further investigation.

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The objective of this study was to investigate clinical signs indicating hereditary diseases like equine sarcoid, osteochondrosis (OC) and the idiopathic laryngeal hemiplegia (ILH), and to demonstrate relationships between environment, feeding habits and conformation ("exterieur" evaluation) of the horses. For this purpose, we analyzed veterinary examinations of 403 stallions at the approvals since 1994 examined 493 three-year-old Swiss Warmblood horses, which were shown at the Swiss-Field-Tests in 2005.With the help of the owners a questionnaire on health, environment and feeding habits of the animals was completed. At the same time, the horses were assessed and graded for their "exterieur" (type, conformation, gaits) by judges of the Swiss Sporthorse breeding association. In 11.5% of horses sarcoids were found, 8.7% showed one and 2.8% several tumors.The prevalence of sarcoids in offspring of sires with known sarcoids was not significantly higher than in descendants from stallions without a known history of sarcoids. We found distended joints as a possible symptom of OC in 11.4% of the horses, 3.9% (n = 19) in both tarsal joints.We did not find a relationship between enlarged joints in the offspring and the presence of OC in the sires. Abnormal respiratory noise at work, as a possible sign for ILH, was heard only in 1.2% (n = 6). It is important to note that while we found a high number of sarcoid affected horses compared to other studies, presence of enlarged joints was not very frequent and very few horses showed abnormal respiratory noise. Additionally, we found no correlation between "exterieur" marks and the horse's general health.

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OBJECTIVE: The aim of this study was to evaluate soft tissue image quality of a mobile cone-beam computed tomography (CBCT) scanner with an integrated flat-panel detector. STUDY DESIGN: Eight fresh human cadavers were used in this study. For evaluation of soft tissue visualization, CBCT data sets and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) data sets were acquired. Evaluation was performed with the help of 10 defined cervical anatomical structures. RESULTS: The statistical analysis of the scoring results of 3 examiners revealed the CBCT images to be of inferior quality regarding the visualization of most of the predefined structures. Visualization without a significant difference was found regarding the demarcation of the vertebral bodies and the pyramidal cartilages, the arteriosclerosis of the carotids (compared with CT), and the laryngeal skeleton (compared with MRI). Regarding arteriosclerosis of the carotids compared with MRI, CBCT proved to be superior. CONCLUSIONS: The integration of a flat-panel detector improves soft tissue visualization using a mobile CBCT scanner.

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BACKGROUND: Oxidative killing is the primary defense against surgical pathogens; risk of infection is inversely related to tissue oxygenation. Subcutaneous tissue oxygenation in obese patients is significantly less than in lean patients during general anesthesia. However, it remains unknown whether reduced intraoperative tissue oxygenation in obese patients results from obesity per se or from a combination of anesthesia and surgery. In a pilot study, we tested the hypothesis that tissue oxygenation is reduced in spontaneously breathing, unanesthetized obese volunteers. METHODS: Seven lean volunteers with a body mass index (BMI) of 22 +/- 2 kg/m(2) were compared to seven volunteers with a BMI of 46 +/- 4 kg/m(2). Volunteers were subjected to the following oxygen challenges: (1) room air; (2) 2 l/min oxygen via nasal prongs, (3) 6 l/min oxygen through a rebreathing face mask; (4) oxygen as needed to achieve an arterial oxygen pressure (arterial pO(2)) of 200 mmHg; and (5) oxygen as needed to achieve an arterial pO(2) of 300 mmHg. The oxygen challenges were randomized. Arterial pO(2) was measured with a continuous intraarterial blood gas analyzer (Paratrend 7); deltoid subcutaneous tissue oxygenation was measured with a polarographic microoxygen sensor (Licox). RESULTS: Subcutaneous tissue oxygenation was similar in lean and obese volunteers: (1) room air, 52 +/- 10 vs 58 +/- 8 mmHg; (2) 2 l/min, 77 +/- 25 vs 79 +/- 24 mmHg; (3) 6 l/min, 125 +/- 43 vs 121 +/- 25 mmHg; (4) arterial pO(2) = 200 mmHg, 115 +/- 42 vs 144 +/- 23 mmHg; (5) arterial pO(2) = 300 mmHg, 145 +/- 41 vs 154 +/- 32 mmHg. CONCLUSION: In this pilot study, we could not identify significant differences in deltoid subcutaneous tissue oxygen pressure between lean and morbidly obese volunteers.