60 research outputs found
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Reducing the duration of untreated psychosis and its impact in the U.S.: the STEP-ED study
Background: Early intervention services for psychotic disorders optimally interlock strategies to deliver: (i) Early Detection (ED) to shorten the time between onset of psychotic symptoms and effective treatment (i.e. Duration of Untreated Psychosis, DUP); and (ii) comprehensive intervention during the subsequent 2 to 5 years. In the latter category, are teams (‘First-episode Services’ or FES) that integrate several empirically supported treatments and adapt their delivery to younger patients and caregivers. There is an urgent need to hasten access to established FES in the U.S. Despite improved outcomes for those in treatment, these FES routinely engage patients a year or more after psychosis onset. The Scandinavian TIPS study was able to effectively reduce DUP in a defined geographic catchment. The guiding questions for this study are: can a U.S. adaptation of the TIPS approach to ED substantially reduce DUP and improve outcomes beyond existing FES? Methods/Design The primary aim is to determine whether ED can reduce DUP in the US, as compared to usual detection. ED will be implemented by one FES (STEP) based in southern Connecticut, and usual detection efforts will continue at a comparable FES (PREPR) serving the greater Boston metropolitan area. The secondary aim is to determine whether DUP reduction can improve presentation, engagement and early outcomes in FES care. A quasi-experimental design will compare the impact of ED on DUP at STEP compared to PREPR over 3 successive campaign years. The campaign will deploy 3 components that seek to transform pathways to care in 8 towns surrounding STEP. Social marketing approaches will inform a public education campaign to enable rapid and effective help-seeking behavior. Professional outreach and detailing to a wide variety of care providers, including those in the healthcare, educational and judicial sectors, will facilitate rapid redirection of appropriate patients to STEP. Finally, performance improvement measures within STEP will hasten engagement upon referral. Discussion STEP-ED will test an ED campaign adapted to heterogeneous U.S. pathways to care while also improving our understanding of these pathways and their impact on early outcomes. Trial registration ClinicalTrials.gov: NCT02069925. Registered 20 February 2014
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients.
OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs.
DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification.
PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries.
MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes.
RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure.
CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome
Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries
BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p
Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study
BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P < 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P < 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223
Crack identification in beams using Hilbert transform, kurtosis and mode shape rotation deviation curve
An inverse problem of diagnosing cracks using empirical mode decomposition (EMD) and Hilbert transform (HT) is proposed based on theoretically obtained vibration data of classically supported structural beam elements. The procedure to obtain natural frequencies, mode shapes and dynamic response to excitation force of pristine and damaged beams is provided. Three different damage indices are used for detecting the crack, identifying the crack height and locating the damage. It is shown that intrinsic mode functions (IMFs), instantaneous frequency time (IF) and amplitude time (A) distributions extracted from dynamically acquired response signals are able to provide information about the existence and severity of crack. This study is the first in terms of (1) employing temporal and spatial signals along with HT, (2) presenting kurtosis usage for beams with different boundary conditions and (3) deriving the deviation curves for identifying the defects in structural beam elements. The proposed procedure and damage metrics are shown to be capable of detecting cracks as small as 4-5% of beam height, and are vigorous and noise robust. An inverse problem of diagnosing cracks using empirical mode decomposition (EMD) and Hilbert transform (HT) is proposed based on theoretically obtained vibration data of classically supported structural beam elements. The procedure to obtain natural frequencies, mode shapes and dynamic response to excitation force of pristine and damaged beams is provided. Three different damage indices are used for detecting the crack, identifying the crack height and locating the damage. It is shown that intrinsic mode functions (IMFs), instantaneous frequency time (IF) and amplitude time (A) distributions extracted from dynamically acquired response signals are able to provide information about the existence and severity of crack. This study is the first in terms of (1) employing temporal and spatial signals along with HT, (2) presenting kurtosis usage for beams with different boundary conditions and (3) deriving the deviation curves for identifying the defects in structural beam elements. The proposed procedure and damage metrics are shown to be capable of detecting cracks as small as 4–5% of beam height, and are vigorous and noise robust.</p
The seismic behaviour of RC exterior shear walls used for strengthening of intact and damaged frames
Several strengthening techniques such as steel plate bonding, external post-tensioning, steel bracing, or addition of new structural elements have been widely used to improve the seismic behaviour of structures, which suffer from earthquakes. Especially, adding infill walls and shear walls to the structures are preferred because of the added increase in lateral strength and stiffness. Nevertheless, applications of these techniques have some difficulties in terms of labour, cost, usage, and comfort for occupants. Due to these difficulties, the exterior shear wall, instead of an infill wall, is applied to strengthen structures, especially for public buildings like schools, hospitals, etc. In this study, the seismic behaviours of the exterior shear walls used to strengthen intact and damaged frames were investigated experimentally. For this purpose, reinforced concrete shear walls were positioned in parallel to the exterior sides of the damaged and the intact three-dimensional frames. Both frames were tested under cyclic loads. After the investigation, the hysteresis curve, strength envelope, stiffness degradation, and the energy dissipation capacity were obtained to reveal the seismic behaviour of the strengthening exterior shear walls. In addition to these, the differences in behaviours of the shear walls applied to damaged and intact frames were identified
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