Cost-effective fetal lung volumetry for assessment of congenital diaphragmatic hernia.

OBJECTIVES: (1) To investigate the reproducibility of total fetal lung volume (TFLV) measurements using a free 3D modeling software (3DSlicer); (2) To correlate these measurements with lung-to-head ratio (LHR) or TFLV measured using PACS and; (3) To determine the role of 3DSlicer in predicting perinatal outcomes in cases with congenital diaphragmatic hernia (CDH) who had fetal tracheal occlusion (FETO). METHODS: Retrospective cohort study between 2012 and 2017 at Texas Children's Hospital (2011-2017), including all patients who underwent FETO for CDH. LHR was measured by ultrasound and TFLV was measured by MRI at the time of referral and 6 weeks after FETO using 3DSlicer and PACS. We evaluated intra- and inter-rater reliability of TFLV measurement using 3DSlicer, infant survival to 1 year, need for ECMO and pulmonary hypertension. RESULTS: The intra- and inter-rater reliability of TFLV measured with 3DSlicer was excellent before and after FETO (Intra-class correlation coefficient: 0.98-0.99 and 0.94-0.99, respectively). There was a good correlation between TFLV measured with PACS and with 3DSlicer before and after FETO (r = 0.78 and r = 0.99, respectively). Similarly, there was a good correlation between TFLV measurements using PACS or 3DSlicer and LHR after FETO (r = 0.86 and r = 0.88, respectively). Infants who survived to 1 year had a significantly higher TFLV evaluated with 3DSlicer before FETO compared to non-surviving infants (OR = 1.16[1.1-1.3], p = 0.03) as well as a significantly higher TFLV evaluated by 3DSlicer after FETO (OR = 1.2[1-1.4], p = 0.04). CONCLUSION: Lung volume measurements using free 3DSlicer in infants with severe CDH who underwent FETO are reproducible and reliable, and have comparable predictive capability for survival as those measured using conventional software.

Health Care Disparity and Pregnancy-Related Mortality in the United States, 2005-2014.

OBJECTIVE: To quantitate the contribution of various demographic factors to the U.S. maternal mortality ratio. METHODS: This was a retrospective observational study. We analyzed data from the Centers for Disease Control and Prevention (CDC) National Center for Health Statistics database and the Detailed Mortality Underlying Cause of Death database (CDC WONDER) from 2005 to 2014 that contains mortality and population counts for all U.S. counties. Bivariate correlations between the maternal mortality ratio and all maternal demographic, lifestyle, health, and medical service utilization characteristics were calculated. We performed a maximum likelihood factor analysis with varimax rotation retaining variables that were significant (P<.05) in the univariate analysis to deal with multicollinearity among the existing variables. RESULTS: The United States has experienced an increase in maternal mortality ratio since 2005 with rates increasing from 15 per 100,00 live births in 2005 to 21-22 per 100,000 live births in 2013 and 2014. (P<.001) This increase in mortality was most pronounced in non-Hispanic black women, with ratios rising from 39 to 49 per 100,000 live births. A significant correlation between state mortality ranking and the percentage of non-Hispanic black women in the delivery population was demonstrated. Cesarean deliveries, unintended births, unmarried status, percentage of deliveries to non-Hispanic black women, and four or fewer prenatal visits were significantly (P<.05) associated with the increased maternal mortality ratio. CONCLUSION: The current U.S. maternal mortality ratio is heavily influenced by a higher rate of death among non-Hispanic black or unmarried patients with unplanned pregnancies. Racial disparities in health care availability and access or utilization by underserved populations are important issues faced by states seeking to decrease maternal mortality.

The Case for a National Maternal Mortality Review Committee.

The United States has the highest maternal mortality ratio of any high-resource country; the 2014 ratio of 22 per 100,000 live births is in fact four to five times higher than that of the best-performing nations, and recent data suggest that this ratio may be increasing. The causes of this disparity are unknown and may be related to social, economic, cultural, or medical issues or a combination of factors. Repeated counts of categories of maternal death are of little assistance in determining the actual cause of death or in identifying preventive measures. Furthermore, when based on administrative data, such tallies may themselves be inaccurate. We propose the creation of a national maternal mortality review committee, modeled after those in other high-resource nations, to assist in addressing the problem of maternal mortality in the United States.

Trends in the delivery route of twin pregnancies in the United States, 2006-2013.

OBJECTIVES: To determine the trends of cesarean delivery rate among twin pregnancies from 2006 to 2013. STUDY DESIGN: This is a population-based, cross-sectional analysis of twin live births from United State birth data files of the National Center for Health Statistics for calendar years 2006 through 2013. We stratified the population based on the gestational age groups, maternal race/ethnicity, advanced maternal age (AMA) which was defined by age more than 35 years and within the standard birth weight groups (group 1: birth weight 500-1499g, group 2: birth weight 1500-2499g and group 3: birth weight >2500g). We also analyzed the effect of different risk factors for cesarean delivery in twins. RESULTS: There were 1,079,102 infants born of twin gestations in the U.S. from 2006 to 2013, representing a small but significant increase in the proportion of twin births among all births (3.2% in 2006 versus 3.4% in 2013). The rate of cesarean delivery in twin live births peaked at 75.3% in 2009, and was significantly lower (74.8%) in 2013. The rate of the twin live birth with the breech presentation increased steadily from 26.3% in 2006 to 29.1% in 2013. For the fetus of the twin pregnancy presented as breech, the cesarean delivery rate peaked at 92.2% in 2010, falling slightly but significantly in the ensuing 3 years. The results demonstrated that the decrease in cesarean delivery rate was due to fewer cesareans in non-Hispanic white patients; all other ethnic subgroups showed increasing rates of cesarean delivery throughout the study. Gestational diabetes, gestational hypertension, previous cesarean delivery and breech presentation were all significant risk factors for cesarean delivery during the entire study period. Induction of labor and premature rupture of the membranes were associated with lower rates of cesarean delivery in twins. CONCLUSION: The recent decrease in the cesarean delivery rate in twin gestation appears to be largely attributable to a decline in cesarean among pregnancies complicated by breech presentation in non-Hispanic white women, and may reflect a health care disparity that deserves further research.

Health Care Disparity and State-Specific Pregnancy-Related Mortality in the United States, 2005-2014.

OBJECTIVE: To investigate factors associated with differential state maternal mortality ratios and to quantitate the contribution of various demographic factors to such variation. METHODS: In a population-level analysis study, we analyzed data from the Centers for Disease Control and Prevention National Center for Health Statistics database and the Detailed Mortality Underlying Cause of Death database (CDC WONDER) that contains mortality and population counts for all U.S. counties. Bivariate correlations between maternal mortality ratio and all maternal demographic, lifestyle, health, and medical service utilization characteristics were calculated. We performed a maximum likelihood factor analysis with varimax rotation retaining variables that were significant (P<.05) in the univariate analysis to deal with multicollinearity among the existing variables. RESULTS: The United States has experienced a continued increase in maternal mortality ratio since 2007 with rates of 21-22 per 100,000 live births in 2013 and 2014. This increase in mortality was most dramatic in non-Hispanic black women. There was a significant correlation between state mortality ranking and the percentage of non-Hispanic black women in the delivery population. Cesarean deliveries, unintended births, unmarried status, percentage of non-Hispanic black deliveries, and four or less prenatal visits were significantly (P<.05) associated with increased maternal mortality ratio. CONCLUSION: Interstate differences in maternal mortality ratios largely reflect a different proportion of non-Hispanic black or unmarried patients with unplanned pregnancies. Racial disparities in health care availability, access, or utilization by underserved populations are an important issue faced by states in seeking to decrease maternal mortality.

Birth Rates Among Hispanics and Non-Hispanics and their Representation in Contemporary Obstetric Clinical Trials.

Objective Our study aims were to establish whether subjects enrolled in current obstetric clinical trials proportionately reflects the contemporary representation of Hispanic ethnicities and their birth rates in the United States. Methods Using comprehensive source data over a defined interval (January 2011-September 2015) on birth rates by ethnicity from the Centers for Disease Control and Prevention (CDC), we evaluated the proportional rate by ethnicity, then analyzed the observed to expected relative ratio of enrolled subjects. Results Hispanic women comprise a significant contribution to births in the United States (23% of all births). Systematic analysis of 90 published obstetric clinical trials showed a correlation between inclusion of Hispanic gravidae and the corresponding state's birth rates (r = 0.501, p < 0.001). While the mean was strongly correlated, individual clinical trials may have relatively over-enrolled (n = 31, or 34%) or under-enrolled (n = 33, or 37%) relative to their regional population. In 48% of obstetric clinical trials the Hispanic proportion of the study population was not reported. Conclusion Hispanic gravidae represent a significant number of contemporary U.S. births, and are generally adequately represented as obstetric subjects in clinical trials. However, this is trial-dependent, with significant trial-specific under- and over-enrollment of Hispanic subjects relative to the regional birth population.

Improving the Prediction of Neonatal Outcomes in Isolated Left-Sided Congenital Diaphragmatic Hernia by Direct and Indirect Sonographic Assessment of Liver Herniation.

OBJECTIVES: Liver herniation can be assessed sonographically by either a direct (liver-to-thoracic area ratio) or an indirect (stomach position) method. Our objective was to evaluate the utility of those methods to assess liver herniation for the prediction of neonatal outcomes in patients with isolated left-sided congenital diaphragmatic hernia (CDH). METHODS: We conducted a retrospective cohort study of all patients with CDH who had prenatal assessment and were delivered at Texas Children's Hospital between January 2004 and April 2014. The predictive value of sonographic parameters for mortality and the need for extracorporeal membrane oxygenation was evaluated by univariate, multivariate, and factor analysis and by receiver operating characteristics curves. RESULTS: A total of 77 fetuses with isolated left-sided CDH were analyzed. The lung-to-head ratio, liver-to-thorax ratio, and stomach position (according to the classifications of Kitano et al [Ultrasound Obstet Gynecol 2011; 37:277-282] and Cordier et al [J Matern Fetal Neonatal Med 2015; 28:190-195]) were significantly associated with both neonatal outcomes (P < .03). Significant correlations were observed between all of these sonographic parameters. A combination of the liver-to-thorax ratio and stomach position (Kitano) or stomach position (Cordier) with the lung-to-head ratio increased the area under the receiver operating characteristic curve of the lung-to-head ratio for mortality prediction (0.86 [95% confidence interval, 0.74-0.98], 0.83 [0.72-0.95], and 0.83 [0.74-0.92], respectively). CONCLUSIONS: Sonographic measurements of liver herniation (liver-to-thorax ratio and stomach position) are predictive of neonatal outcomes in isolated left-sided congenital diaphragmatic hernia. Our study shows that the combination of those sonographic measurements of liver herniation and lung size improves the accuracy of predicting mortality in those fetuses.

Reducing obstetric litigation through alterations in practice patterns.

OBJECTIVE: To estimate the extent to which obstetric malpractice claims might be reduced by adherence to a limited number of specific practice patterns. METHODS: We examined all 189 closed perinatal claims between 2000 and 2005 from a single, large, professional liability insurer. Each case was subjected to three separate analyses: 1) whether the adverse outcome was caused by substandard care, 2) what changes in practice likely would have avoided the adverse outcome, regardless of standard-of-care considerations, and 3) to what extent did substandard documentation lead to payment in cases in which there was no objective evidence of substandard care. RESULTS: Seventy percent of claims involving obstetric practice (accounting for 79% of all costs) involved substandard care. Payments in 85% of cases involving non-vaginal birth after cesarean (VBAC) fetal monitoring, 16% of maternal injury cases, 80% of cases involving VBAC, and 54% of shoulder dystocia cases were avoidable had four specific practice and documentation patterns been followed. CONCLUSION: Most money currently paid in conjunction with obstetric malpractice cases is a result of actual substandard care resulting in preventable injury. Well more than half of hospital litigation costs might be avoided if physician practice included: 1) delivery in a facility with 24-hour in-house obstetric coverage; 2) adherence to published high-risk medication protocols; 3) a more conservative approach to VBAC; and 4) use of a comprehensive, standardized procedure note in cases of shoulder dystocia. LEVEL OF EVIDENCE: III.