Meta-Analysis of the Outcome After Postcardiotomy Venoarterial Extracorporeal Membrane Oxygenation in Adult Patients

ObjectiveThis study was planned to pool existing data on outcome and to evaluate the efficacy of postcardiotomy venoarterial extracorporeal membrane oxygenation (VA-ECMO) in adult patients.DesignSystematic review of the literature and meta-analysis.SettingMulti-institutional study.ParticipantsAdult patients with acute heart failure immediately after cardiac surgery.InterventionsVA-ECMO after cardiac surgery. Studies evaluating only heart transplant patients were excluded from this analysis.Measurements and Main ResultsA literature search was performed to identify studies published since 2000. Thirty-one studies reported on 2,986 patients (mean age, 58.1 years) who required postcardiotomy VA-ECMO. The weaning rate from VA-ECMO was 59.5% and hospital survival was 36.1% (95% CI 31.5-40.8). The pooled rate of reoperation for bleeding was 42.9%, major neurological event 11.3%, lower limb ischemia 10.8%, deep sternal wound infection/mediastinitis 14.7%, and renal replacement therapy 47.1%. The pooled mean number of transfused red blood cell units was 17.7 (95% CI 13.3-22.1). The mean stay in the intensive care unit was 13.3 days (95% CI 10.2-16.4). Survivors were significantly younger (mean, 55.7 v 63.6 years, p = 0.015) and their blood lactate level before starting VA-ECMO was lower (mean, 7.7 v 10.7 mmol/L, p = 0.028) than patients who died. One-year survival rate was 30.9% (95% CI 24.3-37.5).ConclusionsPooled data showed that VA-ECMO may salvage one-third of patients unresponsive to any other resuscitative treatment after adult cardiac surgery.</div

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

Prognostic Impact of Prolonged Cross-Clamp Time in Coronary Artery Bypass Grafting

BACKGROUND:The prognostic impact of cross-clamp time (XCT) in patients undergoing isolated coronary artery bypass grafting (CABG) has not been thoroughly investigated.MATERIAL AND METHODS:2957 patients who underwent on-pump isolated CABG from the prospective multicentre E-CABG study were the subjects of this analysis.RESULTS:The mean XCT in this series was 58±25minutes Cross-clamp time was >60 minutes in 1134 patients (38.3%), >75minutes in 619 patients (20.9%) and >90minutes in 296 patients (10.0%). Multivariate analysis showed that XCT was an independent predictor of 30-day mortality (p75minutes (2.9% vs. 1.7%, p=0.002, OR 3.479, 95%CI 1.609-7.520). Analysis of 428 propensity score matched pairs showed that XCT >75minutes was associated with significantly increased risk of early mortality, prolonged use of inotropes, postoperative use of intra-aortic balloon pump, use of extracorporeal membrane oxygenation, atrial fibrillation, prolonged stay in the intensive care unit and of composite major adverse events.CONCLUSIONS:Isolated CABG is currently performed with prolonged XCT in a significant number of patients and this seems to be a determinant of poor early outcome.</p

Measurement of the cross-section for b-jets produced in association with a Z boson at root s=7 TeV with the ATLAS detector ATLAS Collaboration

A measurement is presented of the inclusive cross-section for b-jet production in association with a Z boson in pp collisions at a centre-of-mass energy of root s = 7 TeV. The analysis uses the data sample collected by the ATLAS experiment in 2010, corresponding to an integrated luminosity of approximately 36 pb(-1). The event selection requires a Z boson decaying into high P-T electrons or muons, and at least one b-jet, identified by its displaced vertex, with transverse momentum p(T) > 25 GeV and rapidity vertical bar y vertical bar < 2.1. After subtraction of background processes, the yield is extracted from the vertex mass distribution of the candidate b-jets. The ratio of this cross-section to the inclusive Z cross-section (the average number of b-jets per Z event) is also measured. Both results are found to be in good agreement with perturbative QCD predictions at next-to-leading order

Measurement of charged-particle event shape variables in inclusive root(s)=7 TeV proton-proton interactions with the ATLAS detector

The measurement of charged-particle event shape variables is presented in inclusive inelastic pp collisions at a center-of-mass energy of 7 TeV using the ATLAS detector at the LHC. The observables studied are the transverse thrust, thrust minor, and transverse sphericity, each defined using the final-state charged particles' momentum components perpendicular to the beam direction. Events with at least six charged particles are selected by a minimum-bias trigger. In addition to the differential distributions, the evolution of each event shape variable as a function of the leading charged-particle transverse momentum, charged-particle multiplicity, and summed transverse momentum is presented. Predictions from several Monte Carlo models show significant deviations from data

Search for the standard model Higgs boson in the diphoton decay channel with 4.9fb -1 of pp collision data at √s=7TeV with atlas

A search for the standard model Higgs boson is performed in the diphoton decay channel. The data used correspond to an integrated luminosity of 4.9  fb-1 collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of √s=7  TeV. In the diphoton mass range 110–150 GeV, the largest excess with respect to the background-only hypothesis is observed at 126.5 GeV, with a local significance of 2.8 standard deviations. Taking the look-elsewhere effect into account in the range 110–150 GeV, this significance becomes 1.5 standard deviations. The standard model Higgs boson is excluded at 95% confidence level in the mass ranges of 113–115 GeV and 134.5–136 GeV

Search for the standard model Higgs boson in the diphoton decay channel with 4.9fb -1 of pp collision data at √s=7TeV with atlas

A search for the standard model Higgs boson is performed in the diphoton decay channel. The data used correspond to an integrated luminosity of 4.9  fb-1 collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of √s=7  TeV. In the diphoton mass range 110–150 GeV, the largest excess with respect to the background-only hypothesis is observed at 126.5 GeV, with a local significance of 2.8 standard deviations. Taking the look-elsewhere effect into account in the range 110–150 GeV, this significance becomes 1.5 standard deviations. The standard model Higgs boson is excluded at 95% confidence level in the mass ranges of 113–115 GeV and 134.5–136 GeV

Epiaortic Ultrasound to Prevent Stroke in Coronary Artery Bypass Grafting

Background. Epiaortic ultrasonography (EAU) is a valid imaging method to detect atherosclerotic changes of the ascending aorta and to guide surgical strategies for the prevention of cerebral embolism in patients undergoing isolated coronary artery bypass grafting (CABG). However, its use is not widespread.Methods. The impact of EAU on the outcome after isolated CABG was investigated in patients from the European Multicenter Study on Coronary Artery Bypass Grafting (E-CABG) registry. A systematic review and meta-analysis of the literature was performed to substantiate the findings of this observational study.Results. EAU was performed intraoperatively in 673 of 7241 patients (9.3%) from the E-CABG registry. In the overall series, the rates of stroke without and with aortic manipulation were 0.3% and 1.3%, respectively (P = .003). In 660 propensity score-matched pairs, EAU was associated with significantly lower risk of stroke (0.6% vs 2.6%, P = .007). A literature search yielded 5 studies fulfilling the inclusion criteria. These studies, along with the present one, included 11,496 patients, of whom 3026 (25.7%) underwent intraoperative EAU. Their rate of postoperative stroke was significantly lower than in patients not investigated with EAU (pooled rate, 0.6% vs 1.9%; risk ratio, 0.40; 95% confidence interval, 0.24-0.66; I-2 = 0%). On the basis of these pooled rates, the number needed to treat to prevent 1 stroke is 76.9.Conclusions. Avoiding aortic manipulation is associated with the lowest risk of stroke in patients undergoing CABG. When manipulation of the ascending aorta is planned, EAU is effective in guiding the surgical strategy to reduce the risk for embolic stroke in these patients