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41.
OBJECTIVE: Occasionally, clinicians are presented with a complicated preterm pregnancy where fetal pulmonary maturity testing might be used to help guide management decisions. However, should delivery be allowed if the lecithin to sphingomyelin ratio (L/S ratio) is not quite mature? The incidence of newborn complications after delivery with L/S ratio values of 1.8 and 1.9 is unknown. The purpose of this study was to evaluate the neonatal morbidity and mortality in patients that delivered with these borderline immature results. STUDY DESIGN: All patients who underwent fetal pulmonary maturity testing were prospectively recorded in log books. An L/S ratio of > or = 2.0 was considered mature. Patients with an L/S ratio of 1.8 or 1.9 were considered "borderline immature." These borderline immature cases were evaluated for the gestational age at amniocentesis, the gestational age at delivery, and neonatal outcome. RESULTS: During the 9-year study period, L/S ratio testing was performed on 2038 patients. Of these, 162 preterm patients (7.9%) had an L/S ratio of 1.8 or 1.9 A total of 63 of these 162 patients delivered < 72 hours after the amniocentesis and met study criteria. The pregnancies ranged from 27 to 36 weeks' gestation. There was a 13% incidence (95% confidence interval (CI) of 4% to 30%) of major neonatal morbidity and a 3% incidence (95% CI of 0% to 17%) of neonatal mortality in the 30 pregnancies with an L/S ratio of 1.8. The incidence of major neonatal morbidity was only 3% (95% CI of 0% to 15%) in the 33 patients with an L/S ratio of 1.9, with no cases of mortality (95% CI of 0% to 9%). CONCLUSION: Based on 95% CIs, the data of this study reveal that the maximum risk for major morbidity is < or = 15%, with a mortality risk of < 10% in a preterm newborn delivered with a 1.9 L/S ratio value. The maximum risk is 30% for major morbidity and 17% for mortality in preterm newborns delivered with a 1.8 L/S ratio. This information may help in the decision-making process of whether to deliver or to observe when faced with a borderline immature L/S ratio result in a complicated preterm pregnancy. 相似文献
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Burkhart HM Ashburn DA Konstantinov IE De Oliveira NC De Oliviera NC Benson L Williams WG Van Arsdell GS 《The Journal of thoracic and cardiovascular surgery》2005,130(1):61-65
BACKGROUND: We sought to determine whether evolving techniques of aortic arch reconstruction used during the Norwood procedure decreased the incidence of postoperative aortic arch obstruction. METHODS: Our technique for aortic arch reconstruction in patients undergoing the Norwood procedure has evolved from using an allograft patch (classic group, n = 26) to primary connection of the pulmonary artery and arch (autologous group, n = 20). More recently, we have used a novel technique involving coarctation excision, an extended end-to-end anastomosis on the back of the arch, and a counterincision on the anterior descending aorta to sew in an allograft patch for total arch reconstruction (interdigitating group, n = 33). Cardiac catheterizations performed before stage II palliation were reviewed for aortic diameters at multiple levels in 79 infants (median age, 4.2 months). Aortic arch obstruction was defined as a ratio between the diameters of the arch anastomosis and the descending aorta (coarctation index) of less than 0.7. RESULTS: Overall, 15 (19%) children had aortic arch obstruction. All 15 required aortic intervention (balloon angioplasty, n = 12; surgical patch angioplasty, n = 2; both, n = 1). Aortic arch obstruction rates for the classic, autologous, and interdigitating groups were 46% (n = 12), 15% (n = 3), and 0%, respectively ( P > .001). CONCLUSION: Reconstruction of the aortic arch with excision of ductal and coarctation tissue is associated with lower aortic arch obstruction rates in patients undergoing the Norwood procedure. Arch reconstruction with a novel interdigitating technique decreases the incidence of aortic arch obstruction. 相似文献
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Instrumental and test-retest reliability of saccadic measures 总被引:2,自引:0,他引:2
Little is known about the reliabilities of the various measures of saccade control that can be derived from pro- and anti-saccade tasks. This paper presents correlational results of 2 different studies comprising altogether 446 psychiatrically and neurologically healthy participants in the range of 6-88 years. Saccades were elicited under different stimulation conditions and during task blocks of 100 or 200 trials. Odd-even and split-half correlations determined for study 1 (N = 327, age 9-88 years) were found to be good to excellent (.60 < or = r < or = .97) for most measures and generalisable over the entire life-span. The 19-month test-retest correlations obtained in study 2 (N = 117, age 6-18 years) ranged between .43 and .66 after controlling for age, and suggest moderate stability of individual differences over time during childhood and adolescence. Hence, these parameters are very useful for concurrent validity studies at every age, but less so for predictive validity studies with children and adolescents. 相似文献
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Lorenz J Hauck M Paur RC Nakamura Y Zimmermann R Bromm B Engel AK 《Brain, behavior, and immunity》2005,19(4):283-295
We investigated the effects of expectation on intensity ratings and somatosensory evoked magnetic fields and electrical potentials following painful infrared laser stimuli in six healthy subjects. The stimulus series contained trials preceded by different auditory cues which either contained valid, invalid or no information about the upcoming laser intensity. High and low intensities occurred equally probable across cue types. High intensity stimuli induced greater pain than low intensity across all cue types. Furthermore, laser intensity significantly interacted with cue validity: high intensity stimuli were perceived less painful and low intensity stimuli more painful following invalid compared to valid cues. The amplitude of the evoked magnetic field localized within the contralateral secondary somatosensory cortex (SII) at about 165 ms after laser stimuli varied also both with stimulus intensity and cue validity. The evoked electric potential peaked at about 300 ms after laser stimuli and yielded a single dipole source within a region encompassing the caudal anterior cingulate cortex and posterior cingulate cortex. Its amplitude also varied with stimulus intensity, but failed to show any cue validity effects. This result suggests a priming of early cortical nociceptive sensitivity by cues signaling pain severity. A possible contribution of the SII cortex to the manifestation of nocebo/placebo cognitions is discussed. 相似文献
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