Prenatal risk stratification for isolated congenital diaphragmatic hernia: results of a Japanese multicenter study

Prenatal diagnostic and intervention considerations in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a life-threatening birth defect with significant morbidity and mortality. The prenatal management of a pregnancy with a fetus affected with CDH is complex and requires a multi-disciplinary team approach. An improved understanding of prenatal diagnosis and management is essential to developing strategies to optimize outcomes for these patients. In this review, we explore the current knowledge on diagnosis, severity stratification, prognostic prediction, and indications for fetal intervention in the fetus with CDH.

Development of mortality prediction models for infants with isolated, left-sided congenital diaphragmatic hernia before and after birth

BACKGROUND

Mortality prediction of congenital diaphragmatic hernia (CDH) is essential for developing treatment strategies, including fetal therapy. Several researchers have reported prognostic factors for this rare but life-threatening condition; however, the optimal combination of prognostic factors remains to be elucidated.

OBJECTIVES

This study aimed to develop the most discriminative prenatal and postnatal models to predict the mortality of infants with an isolated left-sided CDH.

METHODS

This multi-institutional retrospective cohort study included infants with CDH born at 15 tertiary hospitals of the Japanese CDH Study Group between 2011 and 2016. We developed multivariable logistic models with every possible combination of predictors and identified models with the highest cross-validated area under the receiver operating characteristic curve (AUC) for prenatal and postnatal predictions.

RESULTS

Among 302 eligible infants, 44 died before discharge. The prenatal mortality prediction model was based on the observed/expected lung area to head circumference ratio (O/E LHR), liver herniation, and stomach herniation (AUC, 0.830). The postnatal mortality prediction model was based on O/E LHR, liver herniation, and the lowest oxygenation index (AUC, 0.944).

CONCLUSION

Our models can facilitate the prenatal and postnatal mortality prediction of infants with isolated left-sided CDH.

The efficacy of the postnatal nasogastric tube position as a prognostic marker of left-sided isolated congenital diaphragmatic hernia

PURPOSE

The prenatal diagnosis of the stomach position in congenital diaphragmatic hernia (CDH) has been a reliable prognostic factor, but few studies have focused on the postnatal position. We therefore evaluated the significance of the nasogastric (NG) tube position just after birth.

METHODS

The Japanese CDH Study Group database enrolled 1037 CDH neonates over 15 years. In our multicenter retrospective study, 464 cases of left-sided isolated CDH with prenatal diagnoses were divided into two groups: NG tube below the diaphragm (BD; n = 190) or above the diaphragm (AD; n = 274). The primary outcome was the 90-day survival rate, and the secondary outcomes were mechanical ventilation duration, hospitalization duration, and recurrence rate.

RESULTS

The BD group had a significantly higher 90-day survival rate (98.4 vs. 89.4%, p < 0.001), shorter mechanical ventilation (11 vs. 19 days, p < 0.001), shorter hospitalization (38 vs. 59 days, p < 0.001), and lower recurrence rate (p = 0.002) than the AD group. A multivariate analysis showed that BD (adjusted odds ratio, 3.68; 95% confidence interval 1.02-13.30) was a favorable prognostic factor for the 90-day survival.

CONCLUSION

The assessment of the NG tube position revealed it to be a reliable prognostic factor of left-sided isolated CDH. Therefore, it should be included as a routine assessment.

Prenatal predictors of mortality in fetuses with congenital diaphragmatic hernia: a systematic review and meta-analysis

PURPOSE

This study aimed to evaluate prenatal predictors of mortality in fetuses with congenital diaphragmatic hernia (CDH).

METHODS

A systematic literature search was performed to identify relevant observational studies that evaluated the ability of lung-to-head ratio (LHR), observed-to-expected LHR (o/e-LHR), observed-to-expected total fetal lung volume (o/e-TFLV), lung-to-thorax transverse area ratio (L/T ratio), intrathoracic herniation of the liver and the stomach, and side of diaphragmatic hernia, using a threshold for the prediction of mortality in fetuses with CDH. Study quality was assessed using the QUADAS-2 tool. Hierarchical summary receiver operating characteristic curves were constructed.

RESULTS

A total of 50 articles were included in this meta-analysis. The QUADAS-2 tool identified a high risk of bias in more than one domain scored in all parameters. Among those parameters, the diagnostic odds ratio of mortality with o/e-LHR < 25%, o/e-TFLV < 25%, and L/T ratio < 0.08 were 11.98 [95% confidence interval (CI) 4.65-30.89], 11.14 (95% CI 5.19-23.89), and 10.28 (95% CI 3.38-31.31), respectively. The predictive values for mortality were similar between the presence of liver herniation and retrocardiac fetal stomach position.

CONCLUSIONS

This systematic review suggests that o/e-LHR, o/e-TFLV, and L/T ratio are equally good predictors of neonatal mortality in fetuses with isolated CDH.

Clinical outcomes and protocol for the management of isolated congenital diaphragmatic hernia based on our prenatal risk stratification system

BACKGROUND/PURPOSE

The aim of this study was to evaluate our prenatal risk stratification system for risk-adjusted management in fetuses with isolated congenital diaphragmatic hernia (CDH).

METHODS

Ninety-four infants prenatally diagnosed with isolated CDH treated between 1998 and 2017 at our institution were included in this retrospective single-center cohort study.

RESULTS

The patients were prenatally classified into four risk groups: Group A (n = 54), which consisted of infants with neither liver-up nor a contralateral lung-to-thorax transverse area (L/T) ratio <0.08. The infants in group A were divided into two subgroups: Group A-1 (n = 24) consisted of mild conditions; and Group A-2 (n = 30) consisted of severe conditions; Group B (n = 23), which consisted of infants with either liver-up or L/T ratio <0.08; and Group C (n = 17), which consisted of infants with both liver-up and L/T ratio <0.08. The rates of survival to discharge in Groups A-1, A-2, B, and C were 100.0%, 100.0%, 87.0%, and 58.8%, respectively. The rates of intact discharge were 91.7%, 90.0%, 52.1%, and 23.5%, respectively.

CONCLUSIONS

Our prenatal risk stratification system demonstrated a significant difference in the severity of postnatal status and clinical outcomes between the groups.

STUDY TYPE

Case Series, Retrospective Review.

LEVELS OF EVIDENCE

LEVEL IV.

Intestinal Perforation during the Stabilization Period in a Preterm Infant with Congenital Diaphragmatic Hernia

Background  Delayed surgery after stabilization of infants with congenital diaphragmatic hernia (CDH) is an accepted strategy. However, the evidence favoring delayed versus immediate surgical repair is limited. We present an extremely rare case of a very low-birth-weight infant with prenatally diagnosed left-sided CDH and unexpected transmural bowel perforations developing within the postnatal stabilization period.

Case Report  A neonate born at 31st week of gestation with a birth weight of 1,470 g with antenatally diagnosed left-sided CDH presented with bowel dilation leading to transmural bowel perforations on the 2nd day of life. Meconium pleuroperitonitis resulted in severe systemic inflammatory response syndrome, pulmonary hypertension, multiple organ failure, and death.

Conclusion  In neonates with CDH deteriorating under standard postnatal management, intestinal perforation, and early surgical intervention should be considered.

Is there a determining factor that predicts mortality in patients with congenital diaphragmatic hernia?

AIM

This study was designed to investigate the factors affecting the prognosis in neonates with congenital diaphragmatic hernia (CDH) who were treated in our clinic. These factors included prenatal lung-head ratio (LHR), prenatal stomach and liver presence in the thorax, blood gases in the first 24 h and the modified ventilation index (MVI).

MATERIAL AND METHODS

The study was carried out retrospectively in 30 neonates with prenatally diagnosed left CDH who were treated in our clinic between January 2007 and 2013. Data were collected, evaluated, and statistically analyzed for gender, birth weight, gestational age, prenatal LHR, prenatal presence of stomach and liver in the thorax, postnatal initial blood gases in the first 24 h and MVI.

RESULTS

The median LHR for non-survivors was 1.49 and for survivors 1.51. No statistically significant difference in LHR was detected between survivors and non-survivors. In 19 neonates, prenatal ultrasonography (USG) revealed intrathoracic stomach, and 9 of these infants died. Intrathoracic liver was seen in 15 neonates, and 9 of these died. A statistically significant difference was not found between survivors and non-survivors in the intrathoracic liver or intrathoracic stomach neonates. A comparison between the non-survivors and survivors showed a median pH value of 7.10 in non-survivors and 7.24 in survivors (p = 0.002). The median PaCO2 value was 69.4 mm Hg in non-survivors and 51.9 mm Hg in survivors (p = 0.01). There were statistically significant differences in pH and PaCO2 values. The median value of MVI was 33 in survivors and 100 in non-survivors. There was a statistically significant difference between overall non-survivors and survivors in the MVI value (p < 0.05).

CONCLUSIONS

Based on the findings, postnatal pH, and PaCO2 and MVI values are favorable prognostic factors in CDH in our selected group of patients.

Risk stratification for congenital diaphragmatic hernia by factors within 24 h after birth

OBJECTIVE

To establish a simple risk stratification system for patients with congenital diaphragmatic hernia (CDH) based on postnatal information within 24 h after birth.

STUDY DESIGN

A multi-institutional retrospective cohort study was conducted including 348 neonates who had isolated CDH born between 2006 and 2010. Based on the two most powerful variables for 90-day survival selected by multivariate analyses, a risk stratification system was established.

RESULTS

Multiple logistic regression analysis identified two adverse prognostic factors: an Apgar score at 1 min (Ap1) of 0-4 (odds ratio (OR) 3.3, P=0.004), and a best oxygenation index (OI) ⩾8.0 (OR 11.4, P<0.001). Based on a combinations of these two factors, patients were classified into three risk categories. The 90-day survival rates in categories 1-3 were 100, 88 and 52%, respectively (P<0.001).

CONCLUSION

Our simple risk stratification system based on Ap1 and best OI was capable of predicting mortality well.

Lung size and liver herniation predict need for extracorporeal membrane oxygenation but not pulmonary hypertension in isolated congenital diaphragmatic hernia: systematic review and meta-analysis

OBJECTIVES

To identify antenatal predictors of persistent pulmonary hypertension (PPH) and the need for extracorporeal membrane oxygenation (ECMO) in fetuses with congenital diaphragmatic hernia (CDH).

METHODS

We performed a systematic literature review on antenatal diagnostic tests in fetuses with isolated CDH. The primary outcomes assessed were PPH within 28 days of age and the need for ECMO. Quality of studies was assessed with the QUADAS-2 tool. Meta-analysis was performed when at least three studies reported on the same test. Sensitivity analysis was performed according to prenatal management of CDH (tracheal occlusion vs expectant management).

RESULTS

Thirty-eight studies met the inclusion criteria. Fifteen reported on the incidence of PPH only, 19 on the need for ECMO only and four reported on both outcomes. The general quality of the studies was moderate; most studies were retrospective (61%) and single-center series (92%). One study included only fetuses undergoing tracheal occlusion, 22 included only fetuses managed expectantly in utero and 15 included both populations. We could not identify antenatal predictors of PPH. The need for ECMO was predicted by parameters indicative of lung size: lung-to-head ratio (LHR) (relative risk (RR) for LHR < 1, 1.65 (95% CI, 1.27-2.14)) and observed/expected LHR (standardized mean difference (SMD), -0.70 (95% CI, -0.98 to -0.42)) measured by ultrasound and observed/expected total lung volume (SMD, -1.00 (95% CI, -1.52 to -0.48)) measured by magnetic resonance imaging. Liver herniation was also associated with an increased risk of need for ECMO (RR, 3.04 (95% CI, 2.23-4.14)). These results were confirmed by a sensitivity analysis of studies that included only expectantly managed cases. Data on vascular assessment for the prediction of PPH could not be pooled as most of the parameters were evaluated in a single series or in different series by the same principal investigator.

CONCLUSIONS

In fetuses with CDH, lung size and liver herniation predict the need for ECMO, however a predictor for PPH is still lacking. Further studies aimed at diagnosing impaired vascular development in utero should therefore be undertaken. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Predictive Value of MRI Findings for the Identification of a Hernia Sac in Fetuses With Congenital Diaphragmatic Hernia

OBJECTIVE

The purpose of this study was to identify MRI features of diaphragmatic hernia sac, as well as to assess the accuracy of diagnosing a sac prenatally.

MATERIALS AND METHODS

All fetal MRI examinations performed for intrapleural congenital diaphragmatic hernia (CDH) from 2004 to 2013 were retrospectively reviewed by two pediatric radiologists blinded to the hernia sac status (defined intraoperatively or at autopsy). Reviewers noted whether a sac was present on the basis of identification of the following four MRI findings: 1, meniscus of lung posterior or apical to the hernia contents; 2, encapsulated appearance of hernia contents, exerting less than expected mass effect on the heart and mediastinum; 3, presence of pleural fluid outlining a sac from above; and 4, presence of ascites outlining a sac from below. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each finding and for various combinations. Contingency tables, chi-square testing, and logistic regression were applied to calculate the probability of a sac.

RESULTS

Ninety patients were included: 21 with and 69 without a sac. The first three MRI findings correlated with the presence of a sac. Logistic regression yielded high predicted probability of a sac when one finding was identified (finding 1, 94.4%; finding 2, 96.2%). Adding a second and a third finding improved the probability to 99.7% and 99.9%, respectively. Sensitivity and specificity for the presence of a sac were 0.43 and 0.97, respectively. PPV and NPV were 83.8% and 80%, respectively.

CONCLUSION

On fetal MRI, presence of a hernia sac in CDH can be diagnosed with high specificity when indicative findings are present.

An association between pulmonary hypertension and impaired lung function in infants with congenital diaphragmatic hernia

RATIONALE

Infants with congenital diaphragmatic hernia (CDH) can develop pulmonary hypertension (PH) from decreased number and abnormal muscularization of pulmonary arteries. Normally pulmonary vascular growth and remodeling parallel airspace growth and alveolarization, which exhibits a wide morphologic variation in CDH.

AIM

To assess whether infants with CDH and PH have greater abnormalities in infant pulmonary function testing (IPFT) compared to those without PH.

METHODS

We reviewed results of IPFTs and echocardiograms performed on infants with CDH from 2004 to June 2011. Lung volumes, forced flows and tidal mechanics were standardized according to available reference values. Comparisons between infants with and without PH were performed using linear regression, adjusting for potential confounders.

MAIN RESULTS

Sixty-six infants were included; 18 had PH and 48 did not. Z-score values for functional residual capacity (FRC), residual volume (RV), FRC/total lung capacity (TLC), and RV/TLC were significantly higher in infants with CDH and PH compared to those without PH. Z-score values for forced flows including forced expiratory volume in the first 0.5 sec (FEV0.5) and FEV0.5/forced vital capacity were significantly lower in infants with CDH and PH compared to those without PH. For 29 infants studied on ≥2 occasions, the slopes of FRC, RV, and TLC versus length were significantly higher in those with persistent PH compared to those without.

CONCLUSIONS

Infants with CDH and persistent PH demonstrate greater airspace overdistension with growth compared to those without. Therapies that modify disrupted pulmonary vascular and alveolar formation could potentially improve future care of these patients.

The lung to thorax transverse area ratio has a linear correlation with the observed to expected lung area to head circumference ratio in fetuses with congenital diaphragmatic hernias

BACKGROUND/PURPOSE

The purpose of this study was to clarify the relationship between the lung to thorax transverse area ratio (L/T ratio) and the observed to expected lung area to head circumference ratio (O/E LHR), based on the results of a nationwide Japanese survey conducted in 2011, and to evaluate the compatibility of these prognostic predictors of fetal CDH.

METHODS

Two hundred and forty-two prenatally diagnosed isolated CDH patients born between 2006 and 2010 were included in the present analysis. A regression analysis was conducted to investigate the relationship between the L/T ratio and the O/E LHR based on 191 simultaneous measurements of these parameters in 120 patients.

RESULTS

The linear regression equation between the L/T ratio and the O/E LHR was: L/T ratio=0.0233+(0.00222×O/E LHR), (R=0.847, p<0.0001). According to this equation, 25% of the O/E LHR, the cut-off value used in the fetal intervention for CDH, was equivalent to an L/T ratio of 0.08, a commonly accepted cut-off value for identifying the most severe cases of fetal CDH.

CONCLUSIONS

As there is a positive correlation between the L/T ratio and the O/E LHR, these two parameters proved to be used interchangeably according to the linear regression equation.

Magnetic resonance fetal right lung volumetry and its efficacy in predicting postnatal short-term outcomes of congenital left-sided diaphragmatic hernia

AIM

We aimed to investigate whether the ratio of magnetic resonance imaging (MRI)-measured right lung volume (RLV) to ultrasonography-estimated bodyweight (RLV/BW) and observed-to-expected (o/e) RLV are of diagnostic value in predicting postnatal outcomes of left congenital diaphragmatic hernia (CDH).

MATERIAL AND METHODS

We included 32 CDH patients and 34 control subjects. Manually outlined fetal right lung areas on MRI were multiplied by the slice thickness and added to determine the entire volume. The association between RLV and RLV/BW with gestational age in the controls was examined using regression analysis. RLV/BW and o/e RLV were compared between surviving and non-surviving neonates with CDH.

RESULTS

The expected fetal RLV was derived using the formula RLV (mm(3)) = 1.717 × (gestational weeks)(2.82). In the controls, RLV/BW was nearly constant during the third trimester. The 27 survivors with CDH had a median RLV/BW of 10.7 and a median o/e RLV of 60.0, whereas the five non-surviving neonates had a median RLV/BW of 4.3 and a median o/e RLV of 22.6; the differences were statistically significant.

CONCLUSION

Assessment of fetal lungs by MRI volumetry is reliable for clinical use. RLV/BW and o/e RLV are potential predictors of postnatal outcomes of left CDH.

The current profile and outcome of congenital diaphragmatic hernia: a nationwide survey in Japan

BACKGROUND/PURPOSE

Few nationwide surveys have been reported regarding the perinatal status, clinical course and postnatal outcome of cases with congenital diaphragmatic hernia (CDH). The aim of this study was to review the current profile and the outcomes of a large cohort of CDH cases in Japan.

METHODS

A nationwide retrospective cohort study was conducted on neonates diagnosed to have CDH between January 2006 and December 2010. The questionnaires were sent to 159 representative regional institutions and 109 (68.6%) institutions responded to the preliminary survey which had 674 cases. Eleven institutions which had 60 CDH neonates did not respond to the second questionnaire, and 26 institutions had no cases. Finally, 614 CDH neonates from 72 institutions had been collected and were used in the detailed survey. The perinatal status, clinical course and the postnatal outcome were reviewed. Survival was defined as infants alive at hospital discharge, at the time of transfer or still in the hospital at the time of questionnaire, which was confirmed during the period from July 2011 to November 2011 by the investigators.

RESULTS

Four hundred sixty-three (75.4%) of 614 CDH neonates survived in this study. The overall survival rate of neonates with isolated CDH was 84.0%. A total of 444 (72.0%) patients were prenatally diagnosed, and had a survival rate of 70.8%. Four hundred thirty-three (70.9%) patients were treated with high-frequency oscillatory ventilation (HFOV) as the initial ventilation, 344 (56.0%) patients received inhaled nitric oxide (iNO) and 43 (7.0%) required extracorporeal membrane oxygenation (ECMO). The overall survival rates of the CDH neonates who had been treated using HFOV, iNO and ECMO were 74.3%, 68.3% and 37.2%, respectively.

CONCLUSIONS

This study demonstrated that the current status for CDH treatment in Japan and the overall survival rate were comparable to those of recent reports from other countries.

Recent advances in the management of congenital diaphragmatic hernia

PURPOSE OF REVIEW

Congenital diaphragmatic hernia (CDH) is a rare developmental defect resulting in variable degrees of lung and pulmonary vasculature hypoplasia. Whereas many high-volume centers have recently reported increased survival rates, this has not been the collective trend. One potential explanation for this is inconsistent perinatal care among centers.

RECENT FINDINGS

Significant efforts have been made to identify prenatally those fetuses that will be most severely affected. A number of radiologic features have shown promise for achieving this goal as well as identifying fetuses that may benefit from prenatal intervention. When CDH is antenatally diagnosed, early referral to a tertiary center is recommended. Centers that routinely use postnatal management protocols have demonstrated improved overall survival rates including increased survival in high-risk CDH patients.

SUMMARY

As a result of advancements in perinatal care, more severely affected newborns with CDH are now surviving. These patients may experience a number of associated morbidities which affect not only their health but overall quality of life. A multidisciplinary approach to the long-term care of these patients will allow early identification and management of these morbidities.