Retrospective evaluation of neonates with fatal congenital lung malformation: A single center 15-year forensic autopsy experience

Congenital lung malformation (CLM) is a leading cause of infant mortality. Clinical methods for diagnosing CLM mainly rely on computed tomography, magnetic resonance imaging, ultrasonography, and Doppler. However, forensic identification of the cause of death in neonates is challenging. Unequivocal classification criteria for CLM are missing as its forensic identification is ambiguous. Therefore, we aimed to analyze neonatal death cases at our center to assist in identifying those with congenital lung malformation. This retrospective study identified and classified the causes of deaths of neonates autopsied between January 2008 and April 2023. All cases born alive and died within 28 days with a clear time of death were selected, and forensic experts reviewed their records. The manner, cause of death, and other characteristics were noted and discussed. This retrospective study reveals a steady increase in autopsy cases from 2008 to 2015, attributed to improved parental consent, heightened awareness of autopsy importance, and enhanced medical resources. However, a subsequent decline post-2015 is observed, potentially influenced by advancements in medical technology and prenatal examination protocols. The top causes of neonatal mortality include respiratory diseases, asphyxia, congenital dysplasia, and fetal distress. Congenital lung malformations, particularly bronchopulmonary malformations, constitute a significant portion of congenital anomalies. This study underscores the importance of standardized autopsies and histopathological examinations in diagnosing and understanding CLM. Future research should focus on expanding case collections and elucidating the genetic basis of CLM to improve forensic management and outcomes.

Critical functional lung volumes in neonatal intensive care: evidence and clinical applications

Respiratory disease is common in premature and sick newborn infants and can often necessitate the initiation of intensive care. Newborn infants often suffer from conditions that are associated with decreased lung volumes that occur as a result of abnormal or incomplete lung development. Such conditions are prematurity and respiratory distress syndrome, preterm premature rupture of membranes and the ensuing pulmonary hypoplasia and congenital lung anomalies such as congenital diaphragmatic hernia. These diseases have a structural component manifesting with lower lung volumes and a functional component that can present with increased oxygen and ventilatory requirements. The corresponding decreased functional lung volume is possibly responsible for some unfavourable pulmonary outcomes. Some infants are unable to wean off invasive respiratory support and, in extreme cases, unable to sustain independent breathing that can lead to long-term invasive ventilation or subsequent death. The aim of this review is to summarise the available evidence behind the concept of a critical functional lung volume in neonatal intensive care and describe the clinical implications that arise from decreased functional lung volumes in the main high-risk populations of newborn infants. IMPACT: Newborn infants suffer from diseases such as respiratory distress syndrome, pulmonary hypoplasia and congenital diaphragmatic hernia that are associated with a decrease in the total lung volume and impaired lung function. Critically decreased functional lung volumes during neonatal care are associated with failure to wean off invasive respiratory support, increased mortality and possibly longer-term respiratory complications.

Prediction tools in congenital diaphragmatic hernia

Because congenital diaphragmatic hernia (CDH) is characterized by a spectrum of severity, risk stratification is an essential component of care. In both the prenatal and postnatal periods, accurate prediction of outcomes may inform clinical decision-making, care planning, and resource allocation. This review examines the history and utility of the most well-established risk prediction tools currently available, and provides recommendations for their optimal use in the management of CDH patients.

Prenatally diagnosed case of tricuspid valve dysplasia: A case report with review of the literature

We present a case of fetal tricuspid valve dysplasia (TVD) and pulmonary atresia, diagnosed during a routine obstetric ultrasound scan. Serial fetal echocardiographic evaluations revealed progressively augmented prodigious thickening of the tricuspid valvular and subvalvular structures, which eventually extensively obliterated the right ventricle cavity. Thickened dysplastic valve displayed a "cotton-wool" appearance. Unusual configurations of three vessels in the three-vessel view were also observed on a consecutive gray scale and color Doppler scans. During pregnancy, the fetus exhibited satisfactory growth parameters, and complications of progressive hemodynamic compromise associated with TVD and pulmonary atresia such as grievous hydrops or arrhythmia did not develop till 39 weeks of gravidity.

Evolution and Functional Differentiation of the Diaphragm Muscle of Mammals

Symmorphosis is a concept of economy of biological design, whereby structural properties are matched to functional demands. According to symmorphosis, biological structures are never over designed to exceed functional demands. Based on this concept, the evolution of the diaphragm muscle (DIAm) in mammals is a tale of two structures, a membrane that separates and partitions the primitive coelomic cavity into separate abdominal and thoracic cavities and a muscle that serves as a pump to generate intra-abdominal (Pab ) and intrathoracic (Pth ) pressures. The DIAm partition evolved in reptiles from folds of the pleural and peritoneal membranes that was driven by the biological advantage of separating organs in the larger coelomic cavity into separate thoracic and abdominal cavities, especially with the evolution of aspiration breathing. The DIAm pump evolved from the advantage afforded by more effective generation of both a negative Pth for ventilation of the lungs and a positive Pab for venous return of blood to the heart and expulsive behaviors such as airway clearance, defecation, micturition, and child birth. © 2019 American Physiological Society. Compr Physiol 9:715-766, 2019.

Reproducibility of Lung-to-Head Ratio Ultrasound Measurements in Congenital Diaphragmatic Hernia

OBJECTIVES

This study investigated the reproducibility of standardization of lung-to-head ratio measurements in congenital diaphragmatic hernia (CDH) at our center among sonographers after we standardized the method.

METHODS

We reviewed ultrasound images of 12 fetuses with CDH at Mayo Clinic from 2010 to 2016. Nine operators (1 maternal-fetal medicine specialist with experience in measuring the lung-to-head ratio and 8 sonographers), who were blinded to previous findings, reviewed 33 selected images from 12 fetuses with left CDH. The method for lung-to-head ratio measurement was standardized before starting the measurements. The lung-to-head ratio was assessed by different methods to obtain the lung areas: anteroposterior, longest, and area tracing. We evaluated the correlation between operators using the intraclass correlation coefficient (ICC). We also compared agreement between the sonographers and a physician with experience in measuring the lung-to-head ratio using a Bland-Altman analysis.

RESULTS

The methods with the best interoperator reproducibility were the standardized anteroposterior lung-to-head ratio (ICC, 0.69) and the standardized lung-to-head ratio tracing (ICC, 0.65) compared to the longest lung-to-head ratio (ICC, 0.56). The standardized lung-to-head ratio tracing had the best agreement among sonographers and the physician (bias, 0.11; limits of agreement, -0.27 to +0.49) than the anteroposterior lung-to-head ratio (bias, 0.35; limits of agreement, -0.13 to + 0.83) and the longest lung-to-head ratio (bias, 0.27; limits of agreement, -0.35 to +0.89).

CONCLUSIONS

We demonstrated that the lung-to-head ratio tracing method has high interoperator reproducibility and the best agreement among the operators at our center. Further multicenter studies are necessary to confirm our results.

Spleen Behind the Heart Complicates Lung-to-Head Ratio Measurement in Left-Sided Congenital Diaphragmatic Hernia

In fetuses with left-sided congenital diaphragmatic hernia, intrathoracic herniation of the spleen is a common occurrence. The herniated spleen can reside posterior to the left atrium of the heart in the right hemithorax and is increasingly differentiated from the lung with the use of newer sonographic equipment. Estimation of the neonatal prognosis relies on accurate measurement of fetal lung size, particularly with commonly used measurements such as the lung-to-head ratio. Here we describe how herniation of the spleen behind the heart can complicate measurement of the lung-to-head ratio on sonography and lead to overestimation, with implications for perinatal prognostication and management.

A clinical prediction rule for the severity of congenital diaphragmatic hernias in newborns

BACKGROUND

Congenital diaphragmatic hernia (CDH) is a condition with a highly variable outcome. Some infants have a relatively mild disease process, whereas others have significant pulmonary hypoplasia and hypertension. Identifying high-risk infants postnatally may allow for targeted therapy.

METHODS

Data were obtained on 2202 infants from the Congenital Diaphragmatic Hernia Study Group database from January 2007 to October 2011. Using binary baseline predictors generated from birth weight, 5-minute Apgar score, congenital heart anomalies, and chromosome anomalies, as well as echocardiographic evidence of pulmonary hypertension, a clinical prediction rule was developed on a randomly selected subset of the data by using a backward selection algorithm. An integer-based clinical prediction rule was created. The performance of the model was validated by using the remaining data in terms of calibration and discrimination.

RESULTS

The final model included the following predictors: very low birth weight, absent or low 5-minute Apgar score, presence of chromosomal or major cardiac anomaly, and suprasystemic pulmonary hypertension. This model discriminated between a population at high risk of death (∼50%) intermediate risk (∼20%), or low risk (<10%). The model performed well, with a C statistic of 0.806 in the derivation set and 0.769 in the validation set and good calibration (Hosmer-Lemeshow test, P = .2).

CONCLUSIONS

A simple, generalizable scoring system was developed for CDH that can be calculated rapidly at the bedside. Using this model, intermediate- and high-risk infants could be selected for transfer to high-volume centers while infants at highest risk could be considered for advanced medical therapies.

MRI-based ratio of fetal lung volume to fetal body volume as a new prognostic marker in congenital diaphragmatic hernia

OBJECTIVE

The objective of our study was to evaluate the prognostic accuracy of the MRI-based ratio of fetal lung volume (FLV) to fetal body volume (FBV) for predicting survival and the need for extracorporeal membrane oxygenation (ECMO) therapy in fetuses with congenital diaphragmatic hernia (CDH).

MATERIALS AND METHODS

MRI was performed in 96 fetuses (34 females and 62 males; mean gestational age, 33 ± 5 [SD] weeks; range, 23-39 weeks) with CDH and 44 healthy control subjects. FLV and FBV were measured for each fetus by one of three investigators, and we calculated the FLV/FBV ratio. Additionally, a subgroup analysis of growth-restricted fetuses was performed. Logistic regression analysis was used to model the dependence of survival and ECMO requirement on the FLV/FBV ratio. Prognostic accuracy was evaluated by applying the area under the curve (AUC).

RESULTS

Seventy-eight of the 96 (81%) fetuses survived and 35 (36%) neonates needed ECMO therapy. The FLV/FBV ratio was significantly higher in fetuses who survived (p < 0.0001; AUC = 0.829). Neonates who received ECMO therapy showed a significantly lower prenatal FLV/FBV ratio (p = 0.0001; AUC = 0.811) than neonates who did not need ECMO therapy. A subgroup analysis (n = 13) showed a trend toward a higher FLV/FBV ratio of survivors in comparison with nonsurvivors (p = 0.065; AUC = 0.875).

CONCLUSION

In our study, the MRI-based FLV/FBV ratio was able to predict neonatal survival and ECMO requirement in children with CDH with high accuracy. Unlike other prognostic parameters, FLV/FBV ratio is independent of a reference to a control group and may enhance prognostic accuracy particularly in growth-restricted neonatal patients.

Fetal lung volume and quantification of liver herniation by magnetic resonance imaging in isolated congenital diaphragmatic hernia

OBJECTIVE

To determine associations between fetal lung and liver herniation volumes measured by magnetic resonance imaging (MRI) and mortality/need for extracorporeal membrane oxygenation (ECMO) in cases of isolated congenital diaphragmatic hernia (CDH). A secondary objective was to compare prenatal MRI parameters with two-dimensional ultrasound lung measurements.

METHODS

A retrospective review of medical records of all fetuses with isolated CDH evaluated between January 2004 and July 2012 was performed. The following MRI parameters were measured at 20-32 weeks: observed/expected total fetal lung volume (o/e-TLV), predicted pulmonary volume (PPV), percentage of liver herniated into the fetal thorax (%LH) and the liver/thoracic volume ratio (LiTR). These were compared with the ultrasound-determined lung-to-head ratio (LHR) and the observed/expected LHR (o/e-LHR) in the same cohort. The predictive value of MRI and ultrasound parameters for mortality and the need for ECMO was evaluated by univariate, multivariate and factor analysis and by receiver-operating characteristics curves.

RESULTS

Eighty fetuses with isolated CDH were evaluated. Overall mortality was 18/80 (22.5%). Two newborns died a few hours after birth. ECMO was performed in 29/78 (37.2%) newborns, with a survival rate of 48.3% (14/29). The side of the diaphragmatic defect was not associated with mortality (P = 0.99) or the need for ECMO (P = 0.48). Good correlation was observed among o/e-TLV, PPV, LHR and o/e-LHR as well as between %LH and LiTR (r = 0.89; P < 0.01); however, fetal lung measurements and measures of liver herniation were not correlated (all P > 0.05). All parameters were statistically associated with mortality or the need for ECMO. The best combination of measurements to predict mortality was o/e-TLV and %LH, with 83% accuracy.

CONCLUSION

Mortality and the need for ECMO in neonates with isolated CDH can be best predicted using a combination of MRI o/e-TLV and %LH.

Early fetoscopic tracheal occlusion for extremely severe pulmonary hypoplasia in isolated congenital diaphragmatic hernia: preliminary results

OBJECTIVE

To evaluate the effect of early fetoscopic tracheal occlusion (FETO) (22-24 weeks' gestation) on pulmonary response and neonatal survival in cases of extremely severe isolated congenital diaphragmatic hernia (CDH).

METHODS

This was a multicenter study involving fetuses with extremely severe CDH (lung-to-head ratio < 0.70, liver herniation into the thoracic cavity and no other detectable anomalies). Between August 2010 and December 2011, eight fetuses underwent early FETO. Data were compared with nine fetuses that underwent standard FETO and 10 without fetoscopic procedure from January 2006 to July 2010. FETO was performed under maternal epidural anesthesia, supplemented with fetal intramuscular anesthesia. Fetal lung size and vascularity were evaluated by ultrasound before and every 2 weeks after FETO. Postnatal therapy was equivalent for both treated fetuses and controls. Primary outcome was infant survival to 180 days and secondary outcome was fetal pulmonary response.

RESULTS

Maternal and fetal demographic characteristics and obstetric complications were similar in the three groups (P > 0.05). Infant survival rate was significantly higher in the early FETO group (62.5%) compared with the standard group (11.1%) and with controls (0%) (P < 0.01). Early FETO resulted in a significant improvement in fetal lung size and pulmonary vascularity when compared with standard FETO (P < 0.01).

CONCLUSIONS

Early FETO may improve infant survival by further increases of lung size and pulmonary vascularity in cases with extremely severe pulmonary hypoplasia in isolated CDH. This study supports formal testing of the hypothesis with a randomized controlled trial.

Three-dimensional ultrasonographic assessment of fetal total lung volume as a prognostic factor in primary pleural effusion

OBJECTIVES

The purpose of this study was to predict perinatal outcomes using fetal total lung volumes assessed by 3-dimensional ultrasonography (3DUS) in primary pleural effusion.

METHODS

Between July 2005 and July 2010, total lung volumes were prospectively estimated in fetuses with primary pleural effusion by 3DUS using virtual organ computer-aided analysis software. The first and last US examinations were considered in the analysis. The observed/expected total lung volumes were calculated. Main outcomes were perinatal death (up to 28 days of life) and respiratory morbidity (orotracheal intubation with mechanical respiratory support >48 hours).

RESULTS

Twelve of 19 fetuses (63.2%) survived. Among the survivors, 7 (58.3%) had severe respiratory morbidity. The observed/expected total lung volume at the last US examination before birth was significantly associated with perinatal death (P < .01) and respiratory morbidity (P < .01) as well as fetal hydrops (P < .01) and bilateral effusion (P = .01).

CONCLUSIONS

Fetal total lung volumes may be useful for the prediction of perinatal outcomes in primary pleural effusion.

Fetal pulmonary response after fetoscopic tracheal occlusion for severe isolated congenital diaphragmatic hernia

OBJECTIVE

To estimate the response in lung growth and vascularity after fetal endoscopic tracheal occlusion for severe congenital diaphragmatic hernia in the prediction of neonatal survival.

METHODS

Between January 2006 and December 2010, fetal lung parameters (observed-to-expected lung-to-head ratio; observed-to-expected lung volume; and contralateral lung vascularization index) were evaluated before fetal tracheal occlusion and were evaluated longitudinally every 2 weeks in 72 fetuses with severe isolated congenital diaphragmatic hernia. Thirty-five fetuses underwent fetal endoscopic tracheal occlusion and 37 cases did not.

RESULTS

Survival rate was significantly higher in the fetal endoscopic tracheal occlusion group (54.3%) than in the no fetal endoscopic tracheal occlusion group (5.4%, P<.01). Fetal endoscopic tracheal occlusion resulted in a significant improvement in fetal lung size and pulmonary vascularity when compared with fetuses that did not go to the fetal intervention (increase of the observed-to-expected lung-to-head ratio, observed-to-expected total lung volume, and contralateral pulmonary vascularization index 56.2% compared with 0.3%, 37.9% compared with 0.1%, and 98.6% compared with 0.0%, respectively; P<.01). Receiver operating characteristic curves indicated that the observed-to-expected total fetal lung volume was the single best predictor of neonatal survival before fetal endoscopic tracheal occlusion (cutoff 0.23, area under the curve [AUC] 0.88, relative risk 5.3, 95% confidence interval [CI] 1.4-19.7). However, the contralateral lung vascularization index at 4 weeks after fetal endoscopic tracheal occlusion was more accurate in the prediction of neonatal outcome (cutoff 24.0%, AUC 0.98, relative risk 9.9, 95% CI 1.5-66.9) with the combination of observed-to-expected lung volumes and contralateral lung vascularization index at 4 weeks being the best predictor of outcome (AUC 0.98, relative risk 16.6, 95% CI 2.5-112.3).

CONCLUSION

Fetal endoscopic tracheal occlusion improves survival rate by increasing the lung size and pulmonary vascularity in fetuses with severe congenital diaphragmatic hernia. The pulmonary response after fetal endoscopic tracheal occlusion can be used to predict neonatal survival.

Prediction and probability of neonatal outcome in isolated congenital diaphragmatic hernia using multiple ultrasound parameters

OBJECTIVES

To evaluate the accuracy and probabilities of different fetal ultrasound parameters to predict neonatal outcome in isolated congenital diaphragmatic hernia (CDH).

METHODS

Between January 2004 and December 2010, we evaluated prospectively 108 fetuses with isolated CDH (82 left-sided and 26 right-sided). The following parameters were evaluated: gestational age at diagnosis, side of the diaphragmatic defect, presence of polyhydramnios, presence of liver herniated into the fetal thorax (liver-up), lung-to-head ratio (LHR) and observed/expected LHR (o/e-LHR), observed/expected contralateral and total fetal lung volume (o/e-ContFLV and o/e-TotFLV) ratios, ultrasonographic fetal lung volume/fetal weight ratio (US-FLW), observed/expected contralateral and main pulmonary artery diameter (o/e-ContPA and o/e-MPA) ratios and the contralateral vascularization index (Cont-VI). The outcomes were neonatal death and severe postnatal pulmonary arterial hypertension (PAH).

RESULTS

Neonatal mortality was 64.8% (70/108). Severe PAH was diagnosed in 68 (63.0%) cases, of which 63 died neonatally (92.6%) (P < 0.001). Gestational age at diagnosis, side of the defect and polyhydramnios were not associated with poor outcome (P > 0.05). LHR, o/e-LHR, liver-up, o/e-ContFLV, o/e-TotFLV, US-FLW, o/e-ContPA, o/e-MPA and Cont-VI were associated with both neonatal death and severe postnatal PAH (P < 0.001). Receiver-operating characteristics curves indicated that measuring total lung volumes (o/e-TotFLV and US-FLW) was more accurate than was considering only the contralateral lung sizes (LHR, o/e-LHR and o/e-ContFLV; P < 0.05), and Cont-VI was the most accurate ultrasound parameter to predict neonatal death and severe PAH (P < 0.001).

CONCLUSIONS

Evaluating total lung volumes is more accurate than is measuring only the contralateral lung size. Evaluating pulmonary vascularization (Cont-VI) is the most accurate predictor of neonatal outcome. Estimating the probability of survival and severe PAH allows classification of cases according to prognosis.

A randomized controlled trial of fetal endoscopic tracheal occlusion versus postnatal management of severe isolated congenital diaphragmatic hernia

OBJECTIVE

Severe pulmonary hypoplasia and pulmonary arterial hypertension are associated with reduced survival in congenital diaphragmatic hernia (CDH). We aimed to determine whether fetal endoscopic tracheal occlusion (FETO) improves survival in cases of severe isolated CDH.

METHODS

Between May 2008 and July 2010, patients whose fetuses had severe isolated CDH (lung-to-head ratio < 1.0, liver herniation into the thoracic cavity and no other detectable anomalies) were assigned randomly to FETO or to no fetal intervention (controls). FETO was performed under maternal epidural anesthesia supplemented with fetal intramuscular anesthesia. Tracheal balloon placement was achieved with ultrasound guidance and fetoscopy between 26 and 30 weeks of gestation. All cases that underwent FETO were delivered by the EXIT procedure. Postnatal therapy was the same for both treated fetuses and controls. The primary outcome was survival to 6 months of age. Other maternal and neonatal outcomes were also evaluated.

RESULTS

Twenty patients were enrolled randomly to FETO and 21 patients to standard postnatal management. The mean gestational age at randomization was similar in both groups (P = 0.83). Delivery occurred at 35.6 ± 2.4 weeks in the FETO group and at 37.4 ± 1.9 weeks in the controls (P < 0.01). In the intention-to-treat analysis, 10/20 (50.0%) infants in the FETO group survived, while 1/21 (4.8%) controls survived (relative risk (RR), 10.5 (95% CI, 1.5-74.7), P < 0.01). In the received-treatment analysis, 10/19 (52.6%) infants in the FETO group and 1/19 (5.3%) controls survived (RR, 10.0 (95% CI, 1.4-70.6) P < 0.01).

CONCLUSION

FETO improves neonatal survival in cases with isolated severe CDH.

Current advances in prenatal imaging of congenital diaphragmatic [corrected] hernia

Congenital diaphragmatic hernia, despite advances in therapy, remains a complex condition with significant morbidity and mortality. The etiology of the disorder is still incompletely understood, though the pulmonary hypoplasia and pulmonary hypertension that develop secondarily must be overcome to improve survival. Prenatal US and fetal MRI have helped in the development of a greater understanding of this disease. Also with these modalities, measurement techniques have been developed in an attempt to provide prognosticators for the development of pulmonary hypoplasia and pulmonary hypertension. There is a broad range of approaches for performing these measurements, and variability among imaging centers is noted. Despite inconsistent approaches, these techniques have become the foundation for counseling and prenatal and postnatal therapy. It is hoped that with further research with prenatal US and fetal MRI and the development of innovative medical and surgical therapies that the morbidity and mortality of children with congenital diaphragmatic hernias can be significantly reduced.

Correlation between US and MRI for prenatal lung volumetry in diaphragmatic hernia, and use of Doppler to identify the ipsilateral lung cap

BACKGROUND

Pulmonary hypoplasia is a common cause of neonatal death.

OBJECTIVE

To describe the correlation between relative fetal lung volume (RFLV) and lung-to-head ratio (LHR) in fetuses with unilateral diaphragmatic hernia. Additionally, to describe identification of the ipsilateral lung cap by power Doppler.

MATERIALS AND METHODS

Single-institution study of consecutive fetuses with diaphragmatic hernia. LHR (by US) and RFLV (by MRI) were correlated in fetuses with and without an ipsilateral lung cap seen at MRI. In four, color/power Doppler was used to follow the pulmonary artery of the ipsilateral lung to identify the compressed cap.

RESULTS

The study included 48 fetuses of 20-38 weeks' gestational age (mean, 26 weeks). Mean LHR was 1.52 (range, 0.6-3) in fetuses with a lung cap and 1.15 (range, 0.6-2.58) in fetuses without (P = 0.043). Mean RFLV was 47.4% (range, 18-80%) in fetuses with and 32.9% (range, 14-57%) in fetuses without a lung cap (P = 0.005). RFLV and LHR correlated (r = 0.41, P = 0.01 in those with a cap; r = 0.50, P = 0.05 in those without). Power Doppler identified the ipsilateral lung cap and pulsed Doppler confirmed pulmonary vascularization in four of four fetuses.

CONCLUSION

LHR underestimates lung volume in fetuses with an ipsilateral lung cap. Power Doppler may be useful for identifying the cap.

Three-dimensional ultrasound fetal lung volumes and infant respiratory outcome: a prospective observational study

OBJECTIVE

To determine if fetal lung volumes (FLVs), determined by three-dimensional rotational ultrasound and virtual organ computer-aided analysis software (vocal), correlated with neonatal respiratory outcomes in surviving infants who had a high risk [fetuses with congenital diaphragmatic hernia (CDH)], lower risk [fetuses with anterior wall defects (AWDs)] and no risk (controls) of abnormal antenatal lung growth.

DESIGN

Prospective observational study.

SETTING

Tertiary fetal medicine and neonatal intensive care units.

POPULATION

Sixty fetuses (25 with CDH, 25 with AWDs and ten controls).

METHODS

FLVs were measured and expressed as the percentage of the observed compared with the expected for gestational age.

MAIN OUTCOME MEASURES

Neonatal respiratory outcome was determined by the duration of supplemental oxygen, mechanical ventilation and dependencies, and assessment of lung volume using a gas dilution technique to measure functional residual capacity (FRC).

RESULTS

The infants with CDH had lower FLV results than both the infants with AWDs (P=0.05) and the controls (P<0.05). The infants with CDH had longer durations of mechanical ventilation (P<0.001) and supplementary oxygen (P<0.001) dependence, compared with infants with AWDs. The infants with CDH had a lower median FRC than both the infants with AWDs (P<0.001) and the controls (P<0.001). FLV results correlated significantly with the durations of dependency on ventilation (r= -0.744, P<0.01) and oxygen (r= -0.788, P<0.001), and with FRC results (r=0.429, P=0.001).

CONCLUSIONS

These results suggest that FLVs obtained using three-dimensional rotational ultrasound might be useful in predicting neonatal respiratory outcome in surviving infants who had varying risks of abnormal lung growth. Larger and more comprehensive studies are needed to clarify the role that lung volume measurements have in assessing lung function and growth.

Effect of prenatal tetrandrine administration on transforming growth factor-beta1 level in the lung of nitrofen-induced congenital diaphragmatic hernia rat model

PURPOSE

Tetrandrine (Tet) is a bisbenzylisoquinoline alkaloid isolated from the root of Stephania tetrandra, which has been used in traditional Chinese medicine to treat patients with silicosis, asthma, and pulmonary hypertension, and others and can be used as a pulmonary therapeutic agent. We hypothesized that it can also improve the lung growth in congenital diaphragmatic hernia (CDH) for its multiple biological effects. There are increasing evidences that suggest transforming growth factor beta1(TGF-beta1) plays a crucial role in fetal lung growth and morphogenesis. The aim of this study was to evaluate the effect of prenatal administration of Tet and to investigate its possible mechanism on the expression of TGF-beta1 in the lung of nitrofen-induced CDH rat model.

METHODS

A CDH model was induced in pregnant Sprague-Dawley rats by administration of nitrofen on day 9.5 of gestation (Ed9.5 term, day 22). Tetrandrine (30 mg/kg) was given through gavage (once a day, for 3 days) on Ed11.5. Accordingly, there were 3 groups as follows: control (n = 9), CDH (n = 9), and CDH + Tet (n = 9). All the fetuses were delivered by cesarean delivery on Ed16.5, 18.5, and 21.5, respectively, to check if diaphragmatic hernia existed on each fetus, then the lung tissue weight (LW) and body weight (BW) of each fetus were recorded. Histologic evaluations and TGF-beta1 immunohistochemistry staining in the lung sample were performed for image analysis.

RESULTS

Diaphragmatic hernia was observed in 95 of the 112 rat fetuses in CDH and CDH + Tet groups on Ed18.5 and Ed21.5 (84.8%), the incidence between the 2 groups had no statistical significance (P = .642). Lung weight/body weight in the CDH group and the CDH + Tet group were lower than that in the control group (P < .01), and LW/BW in the CDH group was lower than that in the CDH + Tet group (P < .05). Observed under the light microscope and electron microscope, marked hypoplasia of the lungs in fetuses among the CDH groups was observed, in contrast to improvement of the lungs in CDH + Tet fetuses. Statistical differences in morphological parameters (percentage of alveoli area, counting bronchus) were found even on Ed16.5 when diaphragm had not closed (P < .01). The number of type II pneumocytes and lamellar bodies in each group had no significant difference (P > .05). The immunoreactivity of TGF-beta1 in CDH group and CDH + Tet group were markedly stronger than that in the control group (P < .01). In addition, TGF-beta1 expression in the CDH group was stronger than that in the CDH + Tet group (P < .01).

CONCLUSION

Nitrofen can interfere with lung development early in the fetal rat development before and separate from diaphragm development, and increased expression of TGF-beta1 in the lung of CDH rat model may suppress lung growth and development. Prenatal treatment with Tet can improve the growth of the lung of the nitrofen-induced CDH fetuses and its mechanism seems to be involved in downregulating the expression of TGF-beta1. It is a likely new approach to treat CDH and its coexistent lung hypoplasia by maternal Tet administration.

Changing perspectives on the perinatal management of isolated congenital diaphragmatic hernia in Europe

Congenital diaphragmatic hernia (CDH) should be diagnosed in the prenatal period and prompt referral to a tertiary referral center for imaging, genetic testing, and multidisciplinary counseling. Individual prediction of prognosis is based on the absence of additional anomalies, lung size, and liver herniation. In severe cases, a prenatal endotracheal balloon procedure is currently being offered at specialized centers. Fetal intervention is now also offered to milder cases within a trial, hypothesizing that this may reduce the occurrence of bronchopulmonary dysplasia in survivors. Postnatal management has been standardized by European high-volume centers for the purpose of this and other trials.

Prenatal tetrandrine treatment can reverse the abnormal conditions in the lung of newborn with congenital diaphragmatic hernia

Pulmonary hypoplasia and persistent pulmonary hypertension are the most important reasons for the high morbidity and mortality of congenital diaphragmatic hernia (CDH). Despite surgical advances and advances in neonatal intensive care, the mortality still remains high. Then the research on how to improve prenatal fetal lung growth has become a focus. Some researches involved in fetal surgery, tracheal occlusion, prenatal use of corticosteroids etc., have been carried out in CDH animal models and humans. But the results either showed no benefit for the outcome of CDH or were unproved. Tetrandrine is a bisbenzylisoquinoline alkaloid isolated from the root of Stephania tetrandra. It has been used in traditional Chinese medicine for several decades to treat patients with silicosis, asthma and pulmonary hypertension etc. Some researches showed that prenatal tetrandrine administration can improve the lung development in CDH rat models. We hypothesize that prenatal treatment with tetrandrine can reverse the abnormal condition in the lung of newborn with CDH, and thus decrease the mortality.