Effects Of Therapeutic Approach On The Neonatal Evolution Of Very Low Birth Weight Infants With Patent Ductus Arteriosus

Objective To analyze the effects of treatment approach on the outcomes of newborns (birth weight [BW] < 1,000 g) with patent ductus arteriosus (PDA), from the Brazilian Neonatal Research Network (BNRN) on: death, bronchopulmonary dysplasia (BPD), severe intraventricular hemorrhage (IVH III/IV), retinopathy of prematurity requiring surgical (ROPsur), necrotizing enterocolitis requiring surgery (NECsur), and death/BPD.Methods This was a multicentric, cohort study, retrospective data collection, including newborns (BW < 1000 g) with gestational age (GA) < 33 weeks and echocardiographic diagnosis of PDA, from 16 neonatal units of the BNRN from January 1, 2010 to Dec 31, 2011. Newborns who died or were transferred until the third day of life, and those with presence of congenital malformation or infection were excluded. Groups: G1 - conservative approach (without treatment), G2 - pharmacologic (indomethacin or ibuprofen), G3 - surgical ligation (independent of previous treatment). Factors analyzed: antenatal corticosteroid, cesarean section, BW, GA, 5 min. Apgar score < 4, male gender, Score for Neonatal Acute Physiology Perinatal Extension (SNAPPE II), respiratory distress syndrome (RDS), late sepsis (LS), mechanical ventilation (MV), surfactant (< 2 h of life), and time of MV. Outcomes: death, O2 dependence at 36 weeks (BPD36wks), IVH III/IV, ROPsur, NECsur, and death/BPD36wks. Statistics: Student's t-test, chi-squared test, or Fisher's exact test; Odds ratio (95% CI); logistic binary regression and backward stepwise multiple regression. Software: MedCalc (Medical Calculator) software, version 12.1.4.0. p-values < 0.05 were considered statistically significantResults 1,097 newborns were selected and 494 newborns were included: G1 - 187 (37.8%), G2 - 205 (41.5%), and G3 - 102 (20.6%). The highest mortality was observed in G1 (51.3%) and the lowest in G3 (14.7%). The highest frequencies of BPD36wks (70.6%) and ROPsur were observed in G3 (23.5%). The lowest occurrence of death/BPD36wks occurred in G2 (58.0%). Pharmacological (OR 0.29; 95% CI: 0.14-0.62) and conservative (OR 0.34; 95% CI: 0.14-0.79) treatments were protective for the outcome death/BPD36wks. Conclusion The conservative approach of PDA was associated to high mortality, the surgical approach to the occurrence of BPD36wks and ROPsur, and the pharmacological treatment was protective for the outcome death/BPD36wks.906616623Clyman, R.I., Mechanisms regulating the ductus arteriosus (2006) Biol Neonate., 89, pp. 330-335Benitz, W.E., Treatment of persistent patent ductus arteriosus in preterm infants: Time to accept the null hypothesis? (2010) J Perinatol., 30, pp. 241-252Redline, R.W., Wilson-Costello, D., Hack, M., Placental and other perinatal risk factors for chronic lung disease in very low birth weight infants (2002) Pediatr Res., 52, pp. 713-719Evans, N., Kluckow, M., Early ductal shunting and intraventricular haemorrhage in ventilated preterm infants (1996) Arch Dis Child Fetal Neonatal Ed., 75, pp. 183-F186Noerr, B., Current controversies in the understanding of necrotizing enterocolitis Part 1 (2003) Adv Neonatal Care., 3, pp. 107-120Koch, J., Hensley, G., Roy, L., Brown, S., Ramaciotti, C., Rosenfeld, C.R., Prevalence of spontaneous closure of the ductus arteriosus in neonates at a birth weight of 1000 grams or less (2006) Pediatrics., 117, pp. 1113-1121Afiune, J.Y., Singer, J.M., Leone, C.R., Evolução ecocardiográfica de recém-nascidos com persistência do canal arterial (2005) J Pediatr (Rio J)., 81, pp. 454-460Sosenko, I.R., Fajardo, M.F., Claure, N., Bancalari, E., Timing of patent ductus arteriosus treatment and respiratory outcome in premature infants: A double-blind randomized controlled trial (2012) J Pediatr., 160, pp. 929-935. , e1Laughon, M.M., Simmons, M.A., Bose, C.L., Patency of the ductus arteriosus in the premature infant: Is it pathologic? Should it be treated? (2004) Curr Opin Pediatr., 16, pp. 146-151Clyman, R.I., Chorne, N., Patent ductus arteriosus: Evidence for and against treatment (2007) J Pediatr., 150, pp. 216-219Bose, C.L., Laughon, M., Treatment to prevent patency of the ductus arteriosus: Beneficial or harmful? (2006) J Pediatr., 148, pp. 713-714Clyman, R.I., Couto, J., Murphy, G.M., Patent ductus arteriosus: Are current neonatal treatment options better or worse than no treatment at all? (2012) Semin Perinatol., 36, pp. 123-129Alexander, G.R., Himes, J.H., Kaufman, R.B., Mor, J., Kogan, M., A United States national reference for fetal growth (1996) Obstet Gynecol., 87, pp. 163-168Jhaveri, N., Moon-Grady, A., Clyman, R.I., Early surgical ligation versus a conservative approach for management of patent ductus arteriosus that fails to close after indomethacin treatment (2010) J Pediatr., 157. , 381-7, 387.e1Clyman, R., Cassady, G., Kirklin, J.K., Collins, M., Philips, J.B., III, The role of patent ductus arteriosus ligation in bronchopulmonary dysplasia: Reexamining a randomized controlled trial (2009) J Pediatr., 154, pp. 873-876Mirea, L., Sankaran, K., Seshia, M., Ohlsson, A., Allen, A.C., Aziz, K., Treatment of patent ductus arteriosus and neonatal mortality/morbidities: Adjustment for treatment selection bias (2012) J Pediatr., 161, pp. 689-694. , e1Youn, Y., Lee, J.Y., Lee, J.H., Kim, S.Y., Sung, I.K., Lee, J.Y., Impact of patient selection on outcomes of PDA in very low birth weight infants (2013) Early Hum Dev., 89, pp. 175-17

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

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