Right ventricular myocardial performance index (Tei) in premature infants.

OBJECTIVE: The objective of this study was to evaluate the right ventricular myocardial performance index) based on echocardiography in very low birth weight premature neonates, close to hospital discharge. METHODS: This was a prospective cross-sectional study that included premature neonates with birth weight <1,500 g and gestational age <37 weeks at the Intermediate Neonatal Unit of Bonsucesso Federal Hospital from July 2005 to July 2006. The infants underwent two-dimensional color Doppler echocardiography, being the right ventricular myocardial performance index evaluated close to hospital discharge. We compared the neonatal and echocardiographic variables in neonates with and without bronchopulmonary dysplasia. RESULTS: A total of 81 exams were analyzed. The mean birth (standard deviation) weight and gestational age were 1,140 (235) g and 30 (2.2) weeks, respectively. The incidence of bronchopulmonary dysplasia was 32%. The mean right ventricle myocardial performance index (standard deviation) of the sample was 0.13 (0.06). We found a significant difference in aortic diameter [non-bronchopulmonary dysplasia 0.79 (0.07) vs. bronchopulmonary dysplasia 0.87 (0.11) cm, p=0.003], left ventricle in diastole [non-bronchopulmonary dysplasia 1.4 (0.19) vs. bronchopulmonary dysplasia 1.59 (0.21) cm, p=0.0006], ventricular septal thickness [non-bronchopulmonary dysplasia 0.23 (0.03) vs. bronchopulmonary dysplasia 0.26 (0.05) cm, p=0.032], and "a" measurement [(= sum of the isovolumetric contraction time, ejection time, and isovolumetric relaxation time) when calculating the myocardial performance index (p=0.01)]. CONCLUSION: Higher "a" interval in neonates with bronchopulmonary dysplasia suggests right ventricle diastolic dysfunction. We conclude that the right ventricle myocardial performance index is an important indicator both of ventricular function and for serial follow-up testing of very low birth weight premature neonates, especially those with bronchopulmonary dysplasia.

The clinical value of lung ultrasound in premature infants with bronchopulmonary dysplasia.

OBJECTIVE: This study aimed to explore the risk factors of bronchopulmonary dysplasia in premature infants and the clinical application value of lung ultrasound in the diagnosis of bronchopulmonary dysplasia. METHODS: A total of 80 premature infants with a gestational age of <32 weeks or a birth weight of <1,500 g who were treated in our hospital from January to August 2021 were randomly divided into a bronchopulmonary dysplasia group (n=12) and a non-bronchopulmonary dysplasia group (n=62). The clinical data, lung ultrasound, and X-ray image characteristics of the two groups were compared. RESULTS: Among the 74 preterm infants, 12 preterm infants were diagnosed with bronchopulmonary dysplasia, and 62 preterm infants were determined not to have bronchopulmonary dysplasia. There were significant differences in sex, severe asphyxia, invasive mechanical ventilation, premature membrane ruptures, and intrauterine infection between the two groups (p<0.05). Lung ultrasound showed abnormal pleural lines and alveolar-interstitial syndrome in all 12 patients with bronchopulmonary dysplasia and vesicle inflatable signs in 3 patients. Before clinical diagnosis, the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of lung ultrasound in the diagnosis of bronchopulmonary dysplasia were 98.65, 100, 98.39, 92.31, and 100%, respectively. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of X-rays in the diagnosis of bronchopulmonary dysplasia were 85.14, 75.00, 87.10, 52.94, and 94.74%, respectively. CONCLUSION: The diagnostic efficiency of lung ultrasound for premature bronchopulmonary dysplasia is better than that of X-rays. The application of lung ultrasound can screen patients with bronchopulmonary dysplasia early for timely intervention.

Tracheomegaly among Extremely Preterm Infants on Prolonged Mechanical Ventilation.

By using phantom radiographs, the accuracy of tracheal measurements was established. Preterm infants (≤29 weeks) were enrolled in short (<7 days) and prolonged ventilation (≥28 days) groups. Both groups had 3 weight categories, namely, <1000 g, 1000-1999 g, and >2000 g. Tracheal sizes were measured on serial chest radiographs (CXR). We noted tracheomegaly in association with prolonged ventilation at ≥1000 g.

Covariation of Neonatal Intensive Care Unit-Level Patent Ductus Arteriosus Management and In-Neonatal Intensive Care Unit Outcomes Following Preterm Birth.

OBJECTIVE: To test the hypothesis that neonatal intensive care unit (NICU)-specific changes in patent ductus arteriosus (PDA) management are associated with changes in local outcomes in preterm infants. STUDY DESIGN: This retrospective repeated-measures study of aggregated data included infants born 400-1499 g admitted within 2 days of delivery to NICUs participating in the California Perinatal Quality Care Collaborative. The period 2008-2015 was divided into four 2-year epochs. For each epoch and NICU, we calculated proportions of infants receiving cyclooxygenase inhibitor (COXI) or PDA ligation and determined NICU-specific changes in these therapies between consecutive epochs. Generalized estimating equations were used to examine adjusted relationships between NICU-specific changes in PDA management and contemporaneous changes in local outcomes. RESULTS: We included 642 observations of interepoch change at 119 hospitals summarizing 32 094 infants. NICU-specific changes in COXI use and ligation showed significant dose-response associations with contemporaneous changes in adjusted local outcomes. Each percentage point decrease in NICU-specific proportion treated with either COXI or ligation was associated with a 0.21 percentage point contemporaneous increase in adjusted local in-hospital mortality (95% CI 0.06, 0.33; P = .005) among infants born 400-749 g. In contrast, decreasing NICU-specific ligation rate among infants 1000-1499 g was associated with decreasing adjusted local bronchopulmonary dysplasia (P = .009) and death or bronchopulmonary dysplasia (P = .01). CONCLUSIONS: NICU-specific outcomes of preterm birth co-vary with local PDA management. Treatment for PDA closure may benefit some infants born 400-749 g. Decreasing NICU-specific rates of COXI use or ligation were not associated with increases in local adjusted rates of examined adverse outcomes in larger preterm infants.

Reliability of Echocardiographic Indicators of Pulmonary Vascular Disease in Preterm Infants at Risk for Bronchopulmonary Dysplasia.

OBJECTIVES: To determine the assessment and inter-rater reliability of echocardiographic evaluations of pulmonary vascular disease (PVD) in preterm infants at risk for bronchopulmonary dysplasia. STUDY DESIGN: We prospectively studied echocardiograms from preterm infants (birthweights 500-1250 g) at 7 days of age and 36 weeks postmenstrual age (PMA). Echocardiograms were assessed by both a cardiologist on clinical service and a single research cardiologist. Interpretations were reviewed for inclusion of determinants of PVD and assessed for inter-rater reliability using the Prevalence Adjusted Bias Adjusted Kappa Score (PABAK). RESULTS: One hundred eighty and 188 matching research and clinical echocardiogram reports were available for the 7-day and 36-week PMA studies. At least one of the specific qualitative measures of PVD was missing from 54% of the clinical reports. PVD was diagnosed at 7 days in 31% and 20% of research and clinical interpretations, respectively (PABAK score of 0.54). At 36 weeks, PH was diagnosed in 15.6% and 17.8% of research and clinical interpretations, respectively (PABAK score of 0.80). CONCLUSIONS: Although all qualitative variables of PVD are not consistently provided in echocardiogram reports, the inter-rater reliability of cardiologists evaluating measures of PVD revealed strong agreement, especially at 36 weeks PMA. We speculate that establishment of a protocol for echocardiographic evaluation may improve the identification of PVD in preterm infants.

Intra and interobserver reliability of the interpretation of high-resolution computed tomography on the lungs of premature infants.

CONTEXT AND OBJECTIVE: High-resolution computed tomography (HRCT) of the lungs is more sensitive than radiographs for evaluating pulmonary disease, but little has been described about HRCT interpretation during the neonatal period or shortly afterwards. The aim here was to evaluate the reliability of the interpretation of HRCT among very low birth weight premature infants (VLBWPI; < 1500 g). DESIGN AND SETTING: Cross-sectional study on intra and interobserver reliability of HRCT on VLBWPI. METHODS: 86 VLBWPI underwent HRCT. Two pediatric radiologists analyzed the HRCT images. The reliability was measured by the proportion of agreement, kappa coefficient (KC) and positive and negative agreement indices. RESULTS: For radiologist A, the intraobserver reliability KC was 0.79 (confidence interval, CI: 0.54-1.00) for normal/abnormal examinations; for each abnormality on CT, KC ranged from 0.05 to 1.00. For radiologist B, the intraobserver reliability KC was 0.79 (CI: 0.54-1.00) for normal/abnormal examinations; for each abnormality on CT, KC ranged from 0.37 to 0.83. The interobserver agreement was 88% for normal/abnormal examinations and KC was 0.71 (CI: 0.5- 0.93); for most abnormal findings, KC ranged from 0.51-0.67. CONCLUSION: For normal/abnormal examinations, the intra and interobserver agreements were substantial. For most of the imaging findings, the intraobserver agreement ranged from moderate to substantial. Our data demonstrate that in clinical practice, there is no reason for more than one tomographic image evaluator, provided that this person is well trained in VLBWPI HRCT interpretation. Analysis by different observers should be reserved for research and for difficult cases in clinical contexts.

A new scoring system for computed tomography of the chest for assessing the clinical status of bronchopulmonary dysplasia.

OBJECTIVE: To develop a new scoring system for computed tomography (CT) of the chest for assessing the clinical status of patients with bronchopulmonary dysplasia (BPD) in comparison with a modified Edwards roentgenographic scoring system. STUDY DESIGN: Preterm infants diagnosed with BPD (n = 42) were assessed prospectively by chest CT scan at the time of discharge. Three radiologists classified the CT findings into 1 of 3 categories--hyperexpansion, emphysema, or fibrous/interstitial abnormalities--and developed a new scoring system. We assessed interobserver reproducibility and investigated whether this classification system reflected the severity of BPD in these patients. RESULTS: The CT scores had acceptable reproducibility (coefficient of correlation [cc] = 0.721 to 0.839). The subgroup with a more severe form of BPD had a higher CT score. The CT score correlated with the clinical score at 36 weeks of postmenstrual age (cc = 0.367) and the duration of oxygen therapy (cc = 0.537). Patients who were discharged home on oxygen had higher CT scores than patients who were not. CONCLUSIONS: The new chest CT scoring system may have higher objectivity and accuracy in terms of predischarge assessment of clinical status as well as prediction of the prognosis of patients with BPD.

Late pulmonary tomography assessment in premature infants with bronchopulmonary dysplasia submitted to patent ductus arteriosus management.

OBJECTIVE: To assess through high-resolution computed tomography the pulmonary parenchyma of children prematurely born with both very low birth weight and patent ductus arteriosus submitted to medical or surgical treatment that developed bronchopulmonary dysplasia. METHODS: Between December 2006 and January 2007, 14 children prematurely born with a weight less than 1500 g with bronchopulmonary dysplasia (BPD) and patent ductus arteriosus (PDA) were submitted to high-resolution computed tomography (HRCT). All of them underwent surgical closure of the canal divided into two groups: A - medical (n=6) and B - surgical (n=8). The pool of patients comprised 9 baby boys and 5 girls who were 36.5+/-4.3 month-old. The HRCT were analyzed by two independent observers and quantified in each patient. The statistical analyses were assessed using the Mann-Whitney test, and p<0.05 was considered statistically significant. RESULTS: Three patients presented normal tomographies, being two of A group and one of B. In A, the most frequent finding was multifocal ground-glass opacity. In B, multifocal ground-glass opacity, atelectasis, and low attenuation areas with relatively decreased number and caliber of vessels were prevalent (62.5%). There was a statistically significant difference between both groups, with B having higher averages in the intubation times, use of oxygen, and admission. However, as to the number of injuries found on HRCT there was no statistically significant difference (p=0.0787). CONCLUSION: The lately use of HRCT have shown no significant difference between both medical and surgical treatment aiming at to occlude the PDA in pulmonary parenchyma injuries of premature with PDA that developed bronchopulmonary dysplasia.

Pulmonary fluorodeoxyglucose uptake in infants of very low birth weight with and without intrauterine inflammation.

OBJECTIVE: We compared early pulmonary (18)fluorodeoxyglucose ((18)FDG) uptake in infants who had very low birth weight with and without exposure to intrauterine inflammation by using positron emission tomography (PET). A secondary goal was to correlate (18)FDG uptake with later death or bronchopulmonary dysplasia. METHODS: Within 72 hours of birth, 22 singleton infants between 25 and 30 weeks of gestation had a thoracic PET scan after intravenous (18)FDG. Influx constants (K(i)) for (18)FDG were determined. Placental histology assessed exposure to intrauterine inflammation. RESULTS: Chorioamnionitis was found in 13 infants. Seven of these infants also had evidence of funisitis. No inflammation was detected in the remaining nine infants. Median (minimum, maximum) thoracic K(I) was 0.008 (0.006, 0.011) mL/min/mL in infants with funisitis, 0.006 (0.002, 0.008) in infants with chorioamnionitis only, and 0.006 (0.001, 0.015) in infants with no evidence of intrauterine inflammation (P=.16). No relation was found between K(i) and later death or bronchopulmonary dysplasia. Cord blood interleukin-6 was elevated in newborns with placental inflammation (P=.014). CONCLUSION: Early thoracic PET scanning for metabolically active inflammatory cells does not differ between infants with and without exposure to intrauterine inflammation. Evidence of early intrapulmonary sequestration of inflammatory cells in some infants without chorioamnionitis points to the complex etiology of postnatal inflammation.

Risk factors for bronchopulmonary dysplasia after extracorporeal membrane oxygenation.

OBJECTIVE: To determine risk factors for the development of bronchopulmonary dysplasia (BPD) after treatment with extracorporeal membrane oxygenation (ECMO). DESIGN: Retrospective case-control study. SETTING: Tertiary care level 3 neonatal intensive care unit. PARTICIPANTS: Seventy-three newborns treated with ECMO for severe respiratory failure during a 5-year period, who survived until day of life 28, and who did not have pulmonary hypoplasia as the initial cause for respiratory failure. INTERVENTIONS: None. MAIN OUTCOME MEASURE: The presence of BPD after treatment with ECMO, which was defined as oxygen and/or ventilatory requirements at day of life 28, with characteristic abnormalities seen on chest x-ray film. RESULTS: The age at ECMO initiation was significantly greater for patients with BPD compared with patients without BPD (mean +/- SD, 135 +/- 68 hours vs 50 +/- 37 hours; P < .001). There was an 11.5-fold increased risk for the development of BPD if ECMO was initiated at greater than 96 hours of age. The primary diagnosis of respiratory distress syndrome imparted a 5.2-fold increased risk for the development of BPD. Patients with BPD required ECMO significantly longer than patients without BPD (203 +/- 73 hours vs 122 +/- 51 hours; P < .001). CONCLUSION: These results demonstrate that delayed use of ECMO in treating neonatal respiratory failure is associated with an increased risk for the development of BPD and a longer duration of ECMO therapy.