861 resultados para Intraoperative Awareness


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The adequacy of anesthesia has been studied since the introduction of balanced general anesthesia. Commercial monitors based on electroencephalographic (EEG) signal analysis have been available for monitoring the hypnotic component of anesthesia from the beginning of the 1990s. Monitors measuring the depth of anesthesia assess the cortical function of the brain, and have gained acceptance during surgical anesthesia with most of the anesthetic agents used. However, due to frequent artifacts, they are considered unsuitable for monitoring consciousness in intensive care patients. The assessment of analgesia is one of the cornerstones of general anesthesia. Prolonged surgical stress may lead to increased morbidity and delayed postoperative recovery. However, no validated monitoring method is currently available for evaluating analgesia during general anesthesia. Awareness during anesthesia is caused by an inadequate level of hypnosis. This rare but severe complication of general anesthesia may lead to marked emotional stress and possibly posttraumatic stress disorder. In the present series of studies, the incidence of awareness and recall during outpatient anesthesia was evaluated and compared with that of in inpatient anesthesia. A total of 1500 outpatients and 2343 inpatients underwent a structured interview. Clear intraoperative recollections were rare the incidence being 0.07% in outpatients and 0.13% in inpatients. No significant differences emerged between outpatients and inpatients. However, significantly smaller doses of sevoflurane were administered to outpatients with awareness than those without recollections (p<0.05). EEG artifacts in 16 brain-dead organ donors were evaluated during organ harvest surgery in a prospective, open, nonselective study. The source of the frontotemporal biosignals in brain-dead subjects was studied, and the resistance of bispectral index (BIS) and Entropy to the signal artifacts was compared. The hypothesis was that in brain-dead subjects, most of the biosignals recorded from the forehead would consist of artifacts. The original EEG was recorded and State Entropy (SE), Response Entropy (RE), and BIS were calculated and monitored during solid organ harvest. SE differed from zero (inactive EEG) in 28%, RE in 29%, and BIS in 68% of the total recording time (p<0.0001 for all). The median values during the operation were SE 0.0, RE 0.0, and BIS 3.0. In four of the 16 organ donors, EEG was not inactive, and unphysiologically distributed, nonreactive rhythmic theta activity was present in the original EEG signal. After the results from subjects with persistent residual EEG activity were excluded, SE, RE, and BIS differed from zero in 17%, 18%, and 62% of the recorded time, respectively (p<0.0001 for all). Due to various artifacts, the highest readings in all indices were recorded without neuromuscular blockade. The main sources of artifacts were electrocauterization, electromyography (EMG), 50-Hz artifact, handling of the donor, ballistocardiography, and electrocardiography. In a prospective, randomized study of 26 patients, the ability of Surgical Stress Index (SSI) to differentiate patients with two clinically different analgesic levels during shoulder surgery was evaluated. SSI values were lower in patients with an interscalene brachial plexus block than in patients without an additional plexus block. In all patients, anesthesia was maintained with desflurane, the concentration of which was targeted to maintain SE at 50. Increased blood pressure or heart rate (HR), movement, and coughing were considered signs of intraoperative nociception and treated with alfentanil. Photoplethysmographic waveforms were collected from the contralateral arm to the operated side, and SSI was calculated offline. Two minutes after skin incision, SSI was not increased in the brachial plexus block group and was lower (38 ± 13) than in the control group (58 ± 13, p<0.005). Among the controls, one minute prior to alfentanil administration, SSI value was higher than during periods of adequate antinociception, 59 ± 11 vs. 39 ± 12 (p<0.01). The total cumulative need for alfentanil was higher in controls (2.7 ± 1.2 mg) than in the brachial plexus block group (1.6 ± 0.5 mg, p=0.008). Tetanic stimulation to the ulnar region of the hand increased SSI significantly only among patients with a brachial plexus block not covering the site of stimulation. Prognostic value of EEG-derived indices was evaluated and compared with Transcranial Doppler Ultrasonography (TCD), serum neuron-specific enolase (NSE) and S-100B after cardiac arrest. Thirty patients resuscitated from out-of-hospital arrest and treated with induced mild hypothermia for 24 h were included. Original EEG signal was recorded, and burst suppression ratio (BSR), RE, SE, and wavelet subband entropy (WSE) were calculated. Neurological outcome during the six-month period after arrest was assessed with the Glasgow-Pittsburgh Cerebral Performance Categories (CPC). Twenty patients had a CPC of 1-2, one patient had a CPC of 3, and nine patients died (CPC 5). BSR, RE, and SE differed between good (CPC 1-2) and poor (CPC 3-5) outcome groups (p=0.011, p=0.011, p=0.008, respectively) during the first 24 h after arrest. WSE was borderline higher in the good outcome group between 24 and 48 h after arrest (p=0.050). All patients with status epilepticus died, and their WSE values were lower (p=0.022). S-100B was lower in the good outcome group upon arrival at the intensive care unit (p=0.010). After hypothermia treatment, NSE and S-100B values were lower (p=0.002 for both) in the good outcome group. The pulsatile index was also lower in the good outcome group (p=0.004). In conclusion, the incidence of awareness in outpatient anesthesia did not differ from that in inpatient anesthesia. Outpatients are not at increased risk for intraoperative awareness relative to inpatients undergoing general anesthesia. SE, RE, and BIS showed non-zero values that normally indicate cortical neuronal function, but were in these subjects mostly due to artifacts after clinical brain death diagnosis. Entropy was more resistant to artifacts than BIS. During general anesthesia and surgery, SSI values were lower in patients with interscalene brachial plexus block covering the sites of nociceptive stimuli. In detecting nociceptive stimuli, SSI performed better than HR, blood pressure, or RE. BSR, RE, and SE differed between the good and poor neurological outcome groups during the first 24 h after cardiac arrest, and they may be an aid in differentiating patients with good neurological outcomes from those with poor outcomes after out-of-hospital cardiac arrest.

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JUSTIFICATIVA E OBJETIVOS: A constante de equilíbrio entre o plasma e o sítio efetor (ke0) é utilizada pelos modelos farmacocinéticos para prever a concentração do fármaco em seu local de ação (Ce). Seria interessante que a Ce de propofol fosse semelhante na perda e na recuperação da consciência. O objetivo deste estudo foi avaliar o desempenho clínico de duas diferentes ke0 (rápida = 1,21 min-1 e lenta = 0,26 min-1) com relação à Ce durante a perda e a recuperação da consciência, usando o modelo farmacocinético de Marsh. MÉTODO: Participaram deste estudo 20 voluntários adultos sadios do sexo masculino. em todos os voluntários, administrou-se propofol em regime de infusão alvo-controlada, modelo farmacocinético de Marsh ke0 rápida e, em outra oportunidade, usou-se o mesmo modelo farmacocinético com a ke0 lenta. Inicialmente, o propofol foi infundido em concentração-alvo plasmática de 3,0µg.mL-1. A perda de consciência e a recuperação de consciência basearam-se na resposta ao estímulo verbal. A Ce foi anotada no momento da perda e da recuperação da consciência. RESULTADOS: Na perda e na recuperação da consciência a Ce pela ke0 rápida foi diferente (3,64 ± 0,78 e 1,47 ± 0,29µg.mL-1, respectivamente, p < 0,0001), enquanto com a ke0 lenta a Ce foi semelhante (2,20 ± 0,70 e 2,13 ± 0,43µg.mL-1, respectivamente, p = 0,5425). CONCLUSÕES: do ponto de vista clínico, a ke0 lenta (0,26 min-1) incorporada ao modelo farmacocinético de Marsh apresentou melhor desempenho que a ke0 rápida (1,21 min-1), uma vez que a concentração de propofol prevista em seu local de ação na perda e recuperação da consciência foi semelhante.

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Our social life is characterised by norms that manifest as attitudinal and behavioural uniformities among people. With greater awareness about our social context, we can interact more efficiently. Any theory or account of human interaction that fails to include social concepts could be suggested to lack a critical element. This paper identifies social concepts that need to be supported by future context-aware systems. It discusses the limitations of existing context-aware and Multi-Agent Systems (MAS) to support social psychology theories related to the identification and membership of social groups. We argue thatsocial norms are among the core modeling concepts that future context-aware systems need to capture with the view to support and enhance social interactions. The social concepts identified in this paper could be used to simulate agent interactions imbued with social norms or use ICT to facilitate, assist or enhance social interactions. They also could be used in virtual communities modeling where the awareness of a community as well as the process of joining and exiting a community are important.

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Theories that inform pedagogical practices have positioned young children as innocent, pre-political and egocentric. This paper draws from an action research study that investigates the impact of “transformative storytelling”, where stories purposefully crafted to counter metanarratives, revealed the impact of human greed with one class of children aged five to six years of age. Derrida’s notion of “cinders” provided a concept for investigating the traces or imprints the language of story left behind, amidst the children’s comments and actions, enabling the possibilities of the history of these “cinders” (that is what informed these comments and actions) to be noticed. Readings of some of the children’s responses suggest that children aged five and six years can engage in political discourse through the provocation of “transformative storytelling”, and that their engagement demonstrated the consideration of others through critical awareness and intersubjectivity. These early readings raise questions regarding curriculum content and pedagogical practices in early years education and the validity of ongoing educational goals that incorporate critical awareness and intersubjectivity to equip students with communitarian strategies to counter the individualistic outlook of neoliberalist societies.

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Over the last few years more stringent environmental laws (e.g. the German “Energie¬ein-sparverordnung ENEV” - Energy Performance of Buildings Directive) and soaring energy prices has increased the need for the real estate industry to react and participate in overall energy reduction through efficient house construction and design, as well as upgrading the existing housing stock to be more energy efficient. Therefore the Property Economics Group at Queensland University of Technology in Australia and Nuertingen-Geislingen University in Germany are carrying out research in relation to sustainable housing construction and public awareness of “green” residential property. Part of this research is to gain an understanding of the level of knowledge and importance of these issues to the house buyer and to determine the importance of sustainable housing to the general public. The paper compares data from two different empirical studies; one of studies analyzes the situation in New Zealand, the other is focused on Germany.

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Background: Incidence and mortality from skin cancers including melanoma are highest among men 50 years or older. Thorough skin self-examination may be beneficial to improve skin cancers outcomes.--------- Objectives: To develop and conduct a randomized-controlled trial of a video-based intervention to improve skin self-examination behavior among men 50 years or older.--------- Methods: Pilot work ascertained appropriate targeting of the 12-minute intervention video towards men 50 years or older. Overall, 968 men were recruited and 929 completed baseline telephone assessment. Baseline analysis assessed randomization balance and demographic, skin cancer risk and attitudinal factors associated with conducting a whole-body skin self-examination or receiving a whole-body clinical skin examination by a doctor during the past 12 months.--------- Results: Randomization resulted in well-balanced intervention and control groups. Overall 13% of men reported conducting a thorough skin self-examination using a mirror or the help of another person to check difficult to see areas, while 39% reported having received a whole-body skin examination by a doctor within the past 12 months. Confidence in finding time for and receiving advice or instructions by a doctor to perform a skin self-examination were among the factors associated with thorough skin self-examination at baseline.---------- Conclusions: Men 50 years or older can successfully be recruited to a video-based intervention trial with the aim reduce their burden through skin cancer. Randomization by computer generated randomization list resulted in good balance between control and intervention group and baseline analysis determined factors associated with skin cancer early detection behavior at baseline.

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This paper issues a challenge to the notion of domain-general teaching and learning, positing that different subject areas require distinct approaches to developing student knowledge and understanding. The aim has been to observe and compare awareness and explication of disciplinarity in four senior secondary school subjects: Biology, History, Music and Physics. Specifically, we were interested in: (1) teachers’ concepts of what it means to ‘know the discipline’, to ‘think like a disciplinary expert’ and to ‘teach and learn the discipline’; and (2) how teachers draw these concepts together to build student knowledge in the classroom. The research informs educational practice and policy, in particular curricular initiatives involving interdisciplinary curricula.

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Purpose – The purpose of this paper is to examine the buyer awareness and acceptance of environmental and energy efficiency measures in the New Zealand residential property markets. This study aims to provide a greater understanding of consumer behaviour in the residential property market in relation to green housing issues ---------- Design/methodology/approach – The paper is based on an extensive survey of Christchurch real estate offices and was designed to gather data on the factors that were considered important by buyers in the residential property market. The survey was designed to allow these factors to be analysed on a socio-economic basis and to compare buyer behaviour based on property values. ---------- Findings – The results show that regardless of income levels, buyers still consider that the most important factor in the house purchase decision is the location of the property and price. Although the awareness of green housing issues and energy efficiency in housing is growing in the residential property market, it is only a major consideration for young and older buyers in the high income brackets and is only of some importance for all other buyer sectors of the residential property market. Many of the voluntary measures introduced by Governments to improve the energy efficiency of residential housing are still not considered important by buyers, indicating that a more mandatory approach may have to be undertaken to improve energy efficiency in the established housing market, as these measures are not valued by the buyer. ---------- Originality/value – The paper confirms the variations in real estate buyer behaviour across the full range of residential property markets and the acceptance and awareness of green housing issues and measures. These results would be applicable to most established and transparent residential property markets.

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When the colonisers first came to Australia there was an urgent desire to map, name and settle. This desire, in part, stemmed from a fear of the unknown. Once these tasks were completed it was thought that a sense of identity and belonging would automatically come. In Anglo-Australian geography the map of Australia was always perceived in relationship to the larger map of Europe and Britain. The quicker Australia could be mapped the quicker its connection with the ‘civilised’ world could be established. Official maps could be taken up in official history books and a detailed monumental history could begin. Australians would feel secure in where they were placed in the world. However, this was not the case and anxieties about identity and belonging remained. One of the biggest hurdles was the fear of the open spaces and not knowing how to move across the land. Attempts to transpose colonisers’ use of space onto the Australian landscape did not work and led to confusion. Using authors who are often perceived as writers of national fictions (Henry Lawson, Barbara Baynton, Patrick White, David Malouf and Peter Carey) I will reveal how writing about space becomes a way to create a sense of belonging. It is through spatial knowledge and its application that we begin to gain a sense of closeness and identity. I will also look at how one of the greatest fears for the colonisers was the Aboriginal spatial command of the country. Aborigines already had a strongly developed awareness of spatial belonging and their stories reveal this authority (seen in the work of Lorna Little, Mick McLean) Colonisers attempted to discredit this knowledge but the stories and the land continue to recognise its legitimacy. From its beginning Australian spaces have been spaces of hybridity and the more the colonisers attempted to force predetermined structures onto these spaces the more hybrid they became.