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International audience; Several factors can contribute to the difficulty of aligning the sensors of tracking detectors, including a large number of modules, multiple types of detector technologies, and non-linear strip patterns on the sensors. The latter two of these three factors apply to the CLAS12 CVT, which is a hybrid detector consisting of planar silicon sensors with non-parallel strips, and cylindrical micromegas sensors with longitudinal and arc-shaped strips located within a 5 T superconducting solenoid. To align this detector, we used the Kalman Alignment Algorithm, which accounts for correlations between the alignment parameters without requiring the time-consuming inversion of large matrices. This is the first time that this algorithm has been adapted for use with hybrid technologies, non-parallel strips, and curved sensors. We present the results for the first alignment of the CLAS12 CVT using straight tracks from cosmic rays and from a target with the magnetic field turned off. After running this procedure, we achieved alignment at the level of l. 967 10μm, and the widths of the residual spectra were greatly reduced. These results attest to the flexibility of this algorithm and its applicability to future use in the CLAS12 CVT and other hybrid or curved trackers, such as those proposed for the future Electron-Ion Collider.

Thrombocytopenia or an abnormal coagulation profile is not rare in hospitalised patients who have symptoms consistent with acute pulmonary embolism (PE). Theoretically, coagulopathy is more likely to occur in patients with pneumonia than acute PE. This study aimed to assess whether the presence of coagulopathy could be used to exclude acute PE in patients with symptoms and signs consistent with acute PE. In this study, a significant coagulopathy was defined as a platelet count100×10(9)/l, an international normalised ratio1.5, or activated partial thromboplastin time50 seconds. Patients treated with systemic anticoagulants prior to computed tomography pulmonary angiography were excluded. Of the 986 consecutive patients who required computed tomography pulmonary angiography to exclude acute PE over a four-month period in five hospitals in Western Australia, acute PE was confirmed in 149 patients (15.1%). The incidence of coagulopathy was not significantly different between those with and without acute PE (4 vs 7%, respectively; P=0.161) and between those with and without pneumonia (8 vs 7%, respectively; P=0.505). Positive and negative likelihood ratios of coagulopathy in differentiating acute PE or pneumonia were both unsatisfactory. As a continuous predictor, platelet counts, international normalised ratio, activated partial thromboplastin time and plasma fibrinogen concentrations were also not useful in differentiating between acute PE and other pulmonary pathologies (areas under the receiver operating characteristic curve were all close to 0.5). In conclusion, the presence of significant acquired coagulopathy cannot be used to suggest pneumonia or exclude symptomatic acute PE when the prevalence or pre-test probability of acute PE is not low.

The use of limited transthoracic echocardiography (TTE) has been restricted in patients after cardiac surgery due to reported poor image quality. The authors hypothesized that the hemodynamic state could be evaluated in a high proportion of patients at repeated intervals after cardiac surgery.Prospective observational study.Tertiary university hospital.The study comprised 51 patients aged 18 years or older presenting for cardiac surgery.Patients underwent TTE before surgery and at 3 time points after cardiac surgery. Images were assessed offline using an image quality scoring system by 2 expert observers. Hemodynamic state was assessed using the iHeartScan protocol, and the primary endpoint was the proportion of limited TTE studies in which the hemodynamic state was interpretable at each of the 3 postoperative time points.Hemodynamic state interpretability varied over time and was highest before surgery (90%) and lowest on the first postoperative day (49%) (p0.01). This variation in interpretability over time was reflected in all 3 transthoracic windows, ranging from 43% to 80% before surgery and from 2% to 35% on the first postoperative day (p0.01). Image quality scores were highest with the apical window, ranging from 53% to 77% across time points, and lowest with the subcostal window, ranging from 4% to 70% across time points (p0.01).Hemodynamic state can be determined with TTE in a high proportion of cardiac surgery patients after extubation and removal of surgical drains.

Cardiopulmonary bypass is associated with significant morbidities, and the ideal temperature management during cardiopulmonary bypass remains uncertain. This review assessed the benefits and risks of maintaining normothermia during cardiopulmonary bypass in adult cardiac surgery. A total of 6,731 patients from 44 randomized controlled trials in 14 countries, comparing normothermic (> 34°C) and hypothermic (≤34°C) cardiopulmonary bypass in cardiac surgery (>18 years of age), were identified from MEDLINE (1966 to August 10, 2009), EMBASE (1988 to August 10, 2009), and Cochrane controlled trials register and subject to meta-analysis. Two investigators examined all studies and extracted the data independently. Mortality after normothermic and hypothermic bypass was not significantly different (1.4% vs. 1.9% respectively, relative risk [RR] 1.38, 95% confidence interval [CI] 0.94-2.04, I(2) = 0%, P = 0.10). Hypothermic bypass was, however, associated with an increased risk of allogeneic red blood cells (RR 1.19, 95% CI 1.07-1.34, I(2) = 0%, P = 0.002), fresh frozen plasma (RR 1.54, 95% CI 1.06-2.24, I(2) = 7.7%, P = 0.02), and platelet transfusion (RR 2.53, 95% CI 1.26-5.06, I(2) = 44%, P = 0.009). The risk of stroke, cognitive decline, atrial fibrillation, use of inotropic support or intra-aortic balloon pump, myocardial infarction, all-cause infections, and acute kidney injury after cardiac surgery was not significantly different between the two groups. The differences in the bypass time and targeted perfusion temperature were not significantly related to the risk of mortality and stroke. The current evidence suggests that maintaining normothermia during cardiopulmonary bypass in adult cardiac surgery is as safe as that of hypothermic surgery, and associated with a reduced risk of allogeneic blood transfusion.

Background—Cardiopulmonary bypass and cardiac surgery are associated with a significant systemic inflammatory response that may increase postoperative complications. This meta-analysis assessed whether the benefits and risks of corticosteroid use were dose dependent in adult cardiac surgery.Methods and Results—Randomized controlled trials of the use of corticosteroid prophylaxis in adult cardiac surgery (>18 years of age) requiring cardiopulmonary bypass were selected from MEDLINE (1966 to August 1, 2008), EMBASE (1988 to August 1, 2008), and the Cochrane controlled trials register without any language restrictions. A total of 3323 patients from 50 randomized controlled trials were identified and subject to meta-analysis. Corticosteroid prophylaxis reduced the risk of atrial fibrillation (25.1% versus 35.1%; number needed to treat, 10; relative risk, 0.74; 95% confidence interval [CI], 0.63 to 0.86;PPP=0.03) compared with placebo. The use of corticosteroid was not associated with an increased risk of all-cause infection (relative risk, 0.93; 95% CI, 0.61 to 1.41;P=0.73), but hyperglycemia requiring insulin infusion after corticosteroid prophylaxis was common (28.2%; relative risk, 1.49; 95% CI, 1.11 to 2.01;PConclusions—Evidence suggests that low-dose corticosteroid is as effective as high-dose corticosteroid in reducing the risk of atrial fibrillation and duration of mechanical ventilation but with fewer potential side effects in adult cardiac surgery.

Background The ideal thromboprophylaxis in patients at risk of bleeding is uncertain. This retrospective cohort study assessed the risk factors for complications after using retrievable inferior vena cava (IVC) filters for primary or secondary thromboembolism prophylaxis in patients after major trauma. Methods Using data from radiology, trauma and death registries, the incidence of and risk factors for subsequent deep venous thrombosis (DVT), venous thromboembolism (VTE), and mechanical complications related to retrievable IVC filters in patients, admitted between 2007 and 2012, were assessed in a single trauma centre. Results Of the 2940 major trauma patients admitted during the study period, a retrievable IVC filter was used in 223 patients (7.6%). Thirty-six patients (16%) developed DVT or VTE subsequent to placement of IVC filters (median 20 days, interquartile range 9-33), including 27 with lower limb (DVT), 8 upper limb DVT, and 4 pulmonary embolism. A high Injury Severity Score, tibial/fibular fractures, and a delay in initiating pharmacological thromboprophylaxis after insertion of the filters (14 vs 7 days, P=0.001) were significant risk factors. Thirty patients were lost to follow-up (13%) and their filters were not retrieved. Mechanical complications - including filters adherent to the wall of IVC (4.9%), IVC thrombus (4.0%), and displaced or tilted filters (2.2%) - were common when the filters were left in situ for >50 days. Conclusions A delay in initiating pharmacological thromboprophylaxis or filter removal were associated with an increased risk of subsequent DVT, VTE, and mechanical complications of retrievable IVC filters in patients after major trauma.

Background The ideal thromboprophylaxis in patients at risk of bleeding is uncertain. This retrospective cohort study assessed the risk factors for complications after using retrievable inferior vena cava (IVC) filters for primary or secondary thromboembolism prophylaxis in patients after major trauma. Methods Using data from radiology, trauma and death registries, the incidence of and risk factors for subsequent deep venous thrombosis (DVT), venous thromboembolism (VTE), and mechanical complications related to retrievable IVC filters in patients, admitted between 2007 and 2012, were assessed in a single trauma centre. Results Of the 2940 major trauma patients admitted during the study period, a retrievable IVC filter was used in 223 patients (7.6%). Thirty-six patients (16%) developed DVT or VTE subsequent to placement of IVC filters (median 20 days, interquartile range 9-33), including 27 with lower limb (DVT), 8 upper limb DVT, and 4 pulmonary embolism. A high Injury Severity Score, tibial/fibular fractures, and a delay in initiating pharmacological thromboprophylaxis after insertion of the filters (14 vs 7 days, P=0.001) were significant risk factors. Thirty patients were lost to follow-up (13%) and their filters were not retrieved. Mechanical complications - including filters adherent to the wall of IVC (4.9%), IVC thrombus (4.0%), and displaced or tilted filters (2.2%) - were common when the filters were left in situ for >50 days. Conclusions A delay in initiating pharmacological thromboprophylaxis or filter removal were associated with an increased risk of subsequent DVT, VTE, and mechanical complications of retrievable IVC filters in patients after major trauma.

Background— Optimal thromboprophylaxis for patients at risk of bleeding remains uncertain. This meta-analysis assessed whether intermittent pneumatic compression (IPC) of the lower limbs was effective in reducing venous thromboembolism and whether combining pharmacological thromboprophylaxis with IPC would enhance its effectiveness. Methods and Results— Two reviewers searched MEDLINE, EMBASE, and the Cochrane controlled trial register (1966—February 2013) for randomized, controlled trials and assessed the outcomes and quality of the trials independently. Trials comparing IPC with pharmacological thromboprophylaxis, thromboembolic deterrent stockings, no prophylaxis, and a combination of IPC and pharmacological thromboprophylaxis were considered. Trials that used IPC P I 2 =34%) and pulmonary embolism (1.2% versus 2.8%; absolute risk reduction, 1.6%; 95% CI, 0.9–2.3; relative risk, 0.48; 95% CI, 0.33–0.69; P I 2 =0%). IPC was also more effective than thromboembolic deterrent stockings in reducing deep vein thrombosis and appeared to be as effective as pharmacological thromboprophylaxis but with a reduced risk of bleeding (relative risk, 0.41; 95% CI, 0.25–0.65; P I 2 =0%). Adding pharmacological thromboprophylaxis to IPC further reduced the risk of deep vein thrombosis (relative risk, 0.54; 95% CI, 0.32–0.91; P =0.02; I 2 =0%) compared with IPC alone. Conclusions— IPC was effective in reducing venous thromboembolism, and combining pharmacological thromboprophylaxis with IPC was more effective than using IPC alone.

Background. The role of corticosteroids in severe sepsis and pneumonia remains controversial. This study described the use of L'Abbe and pooled calibration plots to assess the relationship between severity of illness and effectiveness of corticosteroids for severe sepsis. Methods. Randomized controlled trials (RCTs) comparing corticosteroids and placebo from Cochrane Controlled Trial Register, MEDLINE, and EMBASE databases were retrieved. The observed and predicted mortality rates of the placebo groups were used as a measure of the severity of illness of the patients in L'Abbe and calibration plots. Results. A total of 1089 patients from 10 RCTs fulfilled the inclusion criteria and were subject to further analysis. L'Abbe and calibration plots did not suggest significant interactions between the effectiveness of corticosteroids and severity of illness. The pooled calibration plot suggested that the mortality rates of the placebo groups from three studies were higher than predicted. After excluding these studies in the meta-analysis, there was a reduction in the point estimate of benefit of corticosteroids on mortality [odds ratio (OR) 0.97, 95% confidence interval (CI): 0.71-1.33, P=0.87 by a fixed-effect model, P=0.59 by a random-effects model vs OR 0.85, 95 CI: 0.66-1.10%]. Conclusions. The pooled calibration plot suggested that there were excessive deaths in the placebo groups of some RCTs that could explain the apparent benefit of corticosteroids on mortality of patients with severe sepsis. L'Abbe and pooled calibration plots might be useful as adjuncts to assess interactions between severity of illness and effectiveness of an intervention

Major histocompatibility complex (MHC) antigen expression on cells is a prerequisite for immune interaction with activated T-cells. This study examined the ability of sera from patients with systemic lupus erythematosus (SLE) to modulate MHC expression on vascular endothelial cells. SLE sera were able to selectively upregulate MHC class I antigen expression on cultured human umbilical venous endothelial (HUVE) cells, without concomitant induction of MHC class II antigen. The stimulation index (SI) for MHC class I expression produced by SLE sera (1.21 +/- 0.23) was significantly higher than those for normal controls (1.01 +/- 0.10) (P0.0001) and non-SLE patients (1.12 +/- 0.14) (P0.05). Additionally, active SLE patients had higher mean SI than inactive patients (P0.001). Preincubation of SLE sera with Protein A-Sepharose beads conjugated with antibodies against tumor necrosis factor-alpha and interferon-alpha was able to significantly reduce their ability to upregulate class I MHC expression by HUVE cells, indicating that these cytokines were responsible for the modulatory effect. This could be an important mechanism for the immune-mediated vascular injury seen in SLE.

To assess the effects of using dexmedetomidine as a sedative and analgesic agent on length of intensive care unit (ICU) stay, duration of mechanical ventilation, risk of bradycardia, and hypotension in critically ill adult patients.Two researchers searched MEDLINE, EMBASE, and the Cochrane controlled trial register independently for randomized controlled trials comparing dexmedetomidine with a placebo or an alternative sedative agent, without any language restrictions.A total of 2,419 critically ill patients from 24 trials were subject to meta-analysis. Dexmedetomidine was associated with a significant reduction in length of ICU stay [weighted mean difference -0.48 days, 95% confidence interval (CI) -0.18 to -0.78 days, P = 0.002], but not duration of mechanical ventilation, when compared with an alternative sedative agent. There was, however, significant heterogeneity in these two outcomes between the pooled studies. Dexmedetomidine was associated with increased risk of bradycardia requiring interventions in studies that used both a loading dose and maintenance doses0.7 microg kg(-1) h(-1) [relative risk (RR) 7.30, 95% CI 1.73-30.81, P = 0.007]. Risks of hypotension requiring interventions (RR 1.43, 95% CI 0.78-2.6, P = 0.25), delirium (RR 0.79, 95% CI 0.56-1.11, P = 0.18), self-extubation, myocardial infarction, hyperglycemia, atrial fibrillation, and mortality were not significantly different between dexmedetomidine and traditional sedative and analgesic agents.Significant heterogeneity existed between the pooled studies. The limited evidence suggested that dexmedetomidine might reduce length of ICU stay in some critically ill patients, but the risk of bradycardia was significantly higher when both a loading dose and high maintenance doses (0.7 microg kg(-1) h(-1)) were used.