Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Multiple rib fractures cause significant pain and potential for chest wall instability. Despite an emerging trend of surgical management of flail chest injuries, there are no studies examining the effect of rib fracture fixation on respiratory function.', 'Using a novel full thorax human cadaveric breathing model, we sought to explore the effect of flail chest injury and subsequent rib fracture fixation on respiratory outcomes.', 'We used five fresh human cadavers to generate negative breathing models in the left thorax to mimic physiologic respiration. Inspiratory volumes and peak flows were measured using a flow meter for all three chest wall states: intact chest, left-sided flail chest (segmental fractures of ribs 3 - 7), and post-fracture open reduction and internal fixation (ORIF) of the chest wall with a pre-contoured rib specific plate fixation system.', 'A wide variation in the mean inspiratory volumes and peak flows were measured between specimens; however, the effect of a flail chest wall and the subsequent internal fixation of the unstable rib fractures was consistent across all samples. Compared to the intact chest wall, the inspiratory volume decreased by 40 ± 19% in the flail chest model (P = 0.04). Open reduction and internal fixation of the flail chest returned the inspiratory volume to 130 ± 71% of the intact chest volumes (P = 0.68). A similar 35 ± 19% decrease in peak flows was seen in the flail chest (P = 0.007) and this returned to 125 ± 71% of the intact chest following ORIF (P = 0.62).
Does rib Fracture Fixation restore Inspiratory Volume and Peak Flow in a Full Thorax Human Cadaveric Breathing Model?

Diastolic runoff in the abdominal aorta, with subsequent circulatory mesenteric insufficiency, has been postulated as a cause of necrotizing enterocolitis in term infants with congenital heart disease. With this study we sought to determine whether Doppler-flow characteristics in the abdominal aorta can predict which infants are at specific risk, independent of gestational age and type of congenital heart disease.', 'We conducted a case-control study of term infants with congenital heart disease and proven necrotizing enterocolitis (n = 18) compared with gestational age-matched and diagnosis-matched control subjects (n = 20). Abdominal aortic Doppler velocities, time intervals, and reversals were analyzed. Groups were compared, and independent risk factors for necrotizing enterocolitis were determined.', 'The groups were similar with regard to weight, pulse pressure, use of prostaglandins or inotropes, presence of a patent ductus arteriosus, and systolic function. However, 47% of the case subjects with necrotizing enterocolitis had persistent retrograde diastolic flow in the abdominal aorta compared with 15% of the control subjects. When adjusting for multiple risk factors, persistent diastolic flow reversal remained the only factor significantly associated with necrotizing enterocolitis.
Is persistent diastolic flow reversal in abdominal aortic Doppler-flow profiles associated with an increased risk of necrotizing enterocolitis in term infants with congenital heart disease?

Infarct heterogeneity has been shown to be independently associated with adverse outcomes in previous smaller studies. However, it is unknown whether infarct characterization is an independent predictor of all-cause mortality in patients with advanced ischemic cardiomyopathy, after adjusting for clinical risk factors, severity of ischemic mitral regurgitation, incomplete revascularization, and device therapy.', 'A total of 362 patients with ischemic cardiomyopathy (left ventricular dysfunction with >70% stenosis in ≥1 epicardial coronary artery) underwent delayed hyperenhancement-magnetic resonance imaging and coronary angiography between 2002 and 2006. Total myocardial scar and peri-infarct (PI) area were measured using various threshold techniques. Multivariate survival analysis (primary end point of all-cause mortality) was conducted. One hundred fifty-seven deaths occurred during a mean 5.4-year follow-up (mean left ventricular ejection fraction, 23±9%; mean end-systolic volume index, 113±48 mL; mean total myocardial scar %, 25.5±16.0%; mean PI%, 5.7±2.9%). PI% (β=2.07; P<0.001) was an independent predictor of survival, independent of age, end-systolic volume, sex, mitral regurgitation, diabetes mellitus, dyslipidemia, coronary artery disease severity, implantable cardioverter defibrillator, and incomplete revascularization. PI% using 2 to 3 SD technique yielded the highest incremental prognostic power (χ(2) score 149).

Is infarct characterization and quantification by delayed enhancement cardiac magnetic resonance imaging a powerful independent and incremental predictor of mortality in patients with advanced ischemic cardiomyopathy?