Prenatal diagnosis of congenital diaphragmatic hernia and pulmonary hypoplasia and therapeutic strategy

Lung to thorax transverse area ratio as a predictor of neurodevelopmental outcomes in fetuses with congenital diaphragmatic hernia

INTRODUCTION

Infants with congenital diaphragmatic hernia (CDH) are at risk of neurodevelopmental disabilities. This study aimed to investigate the association between lung to thorax transverse area ratio (LTR) and neurodevelopmental outcomes at 3 years of age in fetuses with CDH.

METHODS

We performed a retrospective study of infants with prenatally diagnosed isolated left-sided CDH born in Kyushu University Hospital between 2008 and 2016. We examined the association between prenatal ultrasound findings including LTR and development quotient (DQ) at 36 to 42 months of chronological age.

RESULTS

We identified 34 live-born fetuses with isolated left-sided CDH, of which 30 survived and four died before discharge. The median LTR in the survivors was higher than in the non-survivors (p < 0.01). Among the survivors, 26 had available data on LTR (median 0.12, range 0.08-0.18) and overall DQ at 3 years of age (93, 61-112). Their median gestational age and birth weight were 37.6 (range 34.4-39.1) weeks and 2716 (2.256-3494) grams, respectively. There was no significant difference in overall DQ scores between the two groups divided according to the median LTR values (p = 0.62). LTR values were not associated with overall DQ scores after adjusting for gestational age (p = 0.39). In addition, no association was observed between LTR values and any subscale DQ scores.

CONCLUSION

In fetuses with isolated left-sided CDH, prenatal LTR predicts the mortality but not neurodevelopmental outcomes at 3 years of age.

Efficacy of the circulatory management of an antenatally diagnosed congenital diaphragmatic hernia: outcomes of the proposed strategy

OBJECT

The purpose of this study is to evaluate the outcome of our therapeutic strategy for antenatally diagnosed congenital diaphragmatic hernia (ADCDH).

METHODS

We treated 61 cases of ADCDH according to our strategy. Prostaglandin E1 was required to be maintained the patency of the ductus arteriosus (PDA) in 39 cases (Group I) while it was not administered in 22 cases (Group II). Left ventricular end-diastolic dimension (LVDD) and Tei index were measured with echocardiography on days 0, 2, and 7 after birth. Radical surgery was performed on all cases by day 2.

RESULTS

On day 0, Group I showed smaller LVDD and Tei index than those in Group II. Between day 0 and day 2, these parameters increased significantly in Group I, but not in Group II. On day 7, no significant difference in these parameters was observed between the two groups. Five patients died of cardiac and respiratory failure, resulting in a survival rate of 92 %.

CONCLUSION

Our therapeutic strategy improves the clinical outcome of ADCDH. This can be attributed to two factors: earlier surgery resulting in improved LV function. The latter attenuates pulmonary hypertension and maintains PDA with a consequent decrease in right ventricular afterload to compensate for the low cardiac output resulting from PDA.

Relationship between L/T ratio and LHR in the prenatal assessment of pulmonary hypoplasia in congenital diaphragmatic hernia

The lung to thorax transverse area ratio (L/T ratio) and the lung area to head circumference ratio (LHR) have been widely used for the assessment of pulmonary hypoplasia in fetal congenital diaphragmatic hernia (CDH). The aim of this study was to evaluate the relationship between the L/T ratio and the LHR, and to clarify the characteristics of these two indicators as prognostic predictors by means of retrospective concurrent measurements from the same subjects with prenatally diagnosed fetal CDH. The medical records of 55 fetuses who had undergone a prenatal evaluation of isolated CDH from 1988 to 2006 were studied. The L/T ratio and the LHR were determined as the early values (earliest measurement performed earlier than 33 weeks of gestation) and as the late values (latest measurement performed later than 34 weeks of gestation) and analyzed, as well as the clinical data. Of the 55 infants, 13 died resulting in a 76.4% survival rate. A correlation expressed in the linear equation [(LHR) = 14.4 x (L/T ratio) - 0.11] was recognized between the early L/T ratio and the early LHR. All cases with an early L/T ratio of less than 0.08, or with an early LHR less than 1.2, died. Of the 13 cases, 5 with an early L/T ratio not lower than 0.08, but less than 0.13, died. Of the 17 cases, 4 with an early LHR not lower than 1.2, but less than 2.0, died. All cases with an early L/T ratio not lower than 0.13, or with an early LHR not lower than 2.0, survived. In 24 cases, the late values, which were measured at an interval of more than 4 weeks, were compared with the early values. Although the L/T ratio was consistent, the LHR increased in the late value compared to the early value. A good linear correlation was recognized between the L/T ratio and the LHR in the early phase of gestation, and the cutoff point of the prognostic prediction was determined in both indicators. In contrast to the L/T ratio, a definite cutoff point throughout the gestation may not be available in the LHR, because there is a natural increase of the LHR in the late phase of gestation.

Correlation between lung scintigraphy and long-term outcome in survivors of congenital diaphragmatic hernia

Lung scintigraphy has been used to evaluate the degree of pulmonary hypoplasia in infants with congenital diaphragmatic hernia (CDH). However, the relationship between lung scintigraphy and long-term outcome of CDH remains unclear. The aim of this study is to determine whether lung scintigraphy correlates with long-term pulmonary morbidity and nutritional status in survivors of CDH. Consecutive 31 survivors of CDH were enrolled in this study. The initial scan was performed at 1-2 months when the patients were ready for discharge and the follow-up scan was performed following an approximately 1-year interval. The regional ventilation and perfusion were evaluated using (133)Xe-inhalation and intravenous (99m)Tc-MAA injection, respectively. The ventilation and perfusion of the ipsilateral lung was expressed as a percentage of that of the contralateral lung. Physical growth at 1 and 2 years, and pulmonary morbidity were reviewed from medical records. The ventilation and perfusion of the ipsilateral lung at the follow-up scan increased significantly from those at the initial scan. Ten patients had pulmonary morbidity. The ventilation and perfusion of the ipsilateral lung was significantly lower in the patients with pulmonary morbidity compared to the patients without pulmonary morbidity. The initial ventilation and perfusion of the ipsilateral lung were strongly correlated with body weight at 1 and 2 years (ventilation: R = 0.503, P < 0.01; perfusion: R = 0.760, P < 0.0001). These results suggest that lung scintigraphy is useful to predict long-term pulmonary morbidity and poor nutritional status in survivors of CDH.

Hemodynamic evaluation of a prenatal thoracoamniotic shunt for fetal pleural effusion

AIMS

To evaluate the efficacy of a thoracoamniotic shunt for the treatment of pleural effusion (PE) in the view of hemodynamics.

METHODS

The preload index (PLI) in the inferior vena cava (IVC), the maximal flow velocity of the descending aorta (VAomax), skin edema on the thorax and the ratio of lung to the thorax transverse area (L/T) as measured by ultrasound were evaluated before and after thoracoamniotic shunt placement for 5 fetuses with PE.

RESULTS

The PLI and skin edema on the thorax decreased significantly after shunt placement compared to before shunt placement (PLI before: 0.488 +/- 0.036, after: 0.348 +/- 0.043, P < 0.05; edema before: 15.3 +/- 2.06 mm, after: 9.00 +/- 0.63 mm, P < 0.05). Furthermore, the L/T increased significantly after shunt placement compared to before (before: 0.220 +/- 0.013, after: 0.260 +/- 0.011, P < 0.01). No significant difference in VAomax was seen between before and after shunt placement (before: 101.5 +/ -6.39 cm/s, after: 10.7.6 +/ -5.41 cm/s, P = 0.16).

CONCLUSIONS

The shunt for PE improved PLI especially in the fetal hemodynamics significantly.

Long-term follow-up of patients with high-risk congenital diaphragmatic hernia

BACKGROUND/PURPOSE

Recent advances including prenatal diagnosis, high-frequency oscillatory ventilation, and nitric oxide inhalation therapy have gradually improved the survival of high-risk congenital diaphragmatic hernia. However, the factors affecting the long-term outcome of these patients have not been well established.

METHODS

Thirty-three children with ages 4.1 +/- 2.5 years underwent clinical examination including growth measurements, echocardiography, ventilation, and perfusion scintigraphy.

RESULTS

No late death was observed. Common complications were frequent respiratory tract infection (13 patients) and bowel obstruction (5 patients underwent surgery). Although frequent respiratory tract infection decreased with increasing age, patients with frequent respiratory tract infection had a decreased uptake of lung ventilation and perfusion scintigraphy on the affected side and had a decreased height for age and weight for height. No significant difference in lung ventilation and perfusion scintigraphy was observed between patients treated with and without extracorporeal membrane oxygenation, those requiring oxygen more than 1 month, and between those with and without prenatal diagnosis. Patients with a patch repair had decreased uptake on lung perfusion scintigraphy. Although frequent respiratory tract infection may be owing to hypoplasia of the ipsilateral lung, it may impair recovery of the hypoplastic lung.

CONCLUSION

These results indicate that monitoring for respiratory tract infection in addition to nutritional assessment should be required in the follow-up of patients with congenital diaphragmatic hernia at high risk.

A proposal of new therapeutic strategy for antenatally diagnosed congenital diaphragmatic hernia

PURPOSE

The prognosis of antenatally diagnosed congenital diaphragmatic hernia (ADCDH) is still very poor despite of innovation of various therapeutics. The authors reviewed their new therapeutic strategy of ADCDH from a viewpoint of cardiologic function.

METHODS

The cardiac function in 19 cases of ADCDH was reviewed. The patients, at the age of 0 days, were divided into 2 groups, PG (+) and PG (-), according to the requirement of prostaglandin E1 (PGE1) to attenuate pulmonary hypertension. The left ventricular (LV) end-diastolic dimension (LV diastolic diameter index [LVDI]) and bilateral pulmonary arterial diameters (total pulmonary artery index [TPAI]) were measured on days 0 and 2.

RESULT

Only 1 patient died of cardiac or respiratory failure, and the survivors' postoperative course was uneventful. Eleven patients needed inhalation of nitric oxide (NO), and in 9 of those, PGE1 was administered. The LVDI and TPAI of day 0 in PG (+) were significantly smaller than those in PG (-) and the controls. The LVDI increased from postnatal day 0 to day 2 in both PG (+) and PG (-). Although the LV was too small to output enough volume, the right ventricle successfully compensated for the low output through the ductus arteriosus, kept patent by NO and PGE1.

CONCLUSION

For ADCDH with sever pulmonary hypertension, keeping patent ductus arteriosus with NO and PGE1 plays a critical role in obtaining excellent clinical outcome. Thus, the authors proposed a new therapeutic strategy for ADCDH based on a circulatory management.

Outcome predictors for infants with cystic lung disease

BACKGROUND/PURPOSE

This study aimed at identifying characteristic features indicating congenital cystic adenomatoid malformation of the lung (CCAM) and evaluating the outcome predictors to identify prenatally subgroups of fetuses with significantly different probabilities of mortality or severe respiratory difficulty.

METHODS

Twenty-eight neonates who had undergone antenatal evaluation for cystic lung disease (CLD) were reviewed retrospectively. The patients were divided into 3 groups according to the severity of their clinical course; mild (n = 7), moderate (n = 13), and severe (n = 8). Ultrasonographic findings in the fetus and their pulmonary lesion were evaluated. The normal lung to thorax transverse area ratio (L/T) was measured by ultrasonography.

RESULTS

High echogenicity of the lesion throughout pregnancy and polyhydramnios were frequently seen in CCAM. All of the patients with other CLD showed isoechogenicity at the end of pregnancy. All patients in the severe group had both polyhydramnios and fetal hydrops. L/T was increased in mild and moderate groups, whereas no patient in the severe group had an increase in L/T at the final measurement. Each value of final L/T in the severe group was less than 0.25.

CONCLUSIONS

The subgroup of fetuses with an increased probability of mortality or severe respiratory difficulty could be predicted from the combination of polyhydramnios, fetal hydrops, and a final L/T value of less than 0.25.

Prenatal surgery for congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) has a mortality rate of up to 77% despite optimal pre- and postnatal care. Fetuses with liver herniation, a low lung-to-head ratio, and an early diagnosis before 24 weeks have a particularly poor prognosis. In utero open repair of these fetuses does not improve patient survival. The PLUG (Plug the Lung Until it Grows) technique was reported to be able to reverse pulmonary hypoplasia in CDH. A foam plug or a titanium clip is used and the trachea can be unplugged using Ex Utero Intrapartum Tracheoplasty (EXIT) at birth. Since hysterotomy causes premature labour, a video-fetoscopic intrauterine technique of tracheal occlusion called Fetendo-PLUG was developed. Compared to those who receive standard postnatal care or fetal tracheal occlusion via open hysterotomy, patients who undergo Fetendo-PLUG are reported to have a higher survival rate of 75% and fewer fetal and maternal complications. A recent refinement is to use a detachable balloon for intratracheal occlusion through a single 5 mm port under real-time ultrasound guidance. Without the need for neck dissection, injury to the recurrent laryngeal nerves and trachea and vocal cord paresis can be minimized. The result of this form of treatment for CDH is promising, but further refinement of fetal instrumentation and development of effective tocolytic drugs are still required.

Inhaled nitric oxide with early surgery improves the outcome of antenatally diagnosed congenital diaphragmatic hernia

BACKGROUND/PURPOSE

The outcome of antenatally diagnosed congenital diaphragmatic hernia (CDH) has remained poor despite aggressive therapeutic strategies. Since 1996, the authors have used a new approach including early surgery and inhaled nitric oxide (iNO). The aim of this study is to determine whether early surgery in combination with iNO improves the clinical outcome of antenatally diagnosed CDH.

METHODS

From 1988, 40 consecutive neonates with antenatally diagnosed CDH were admitted to the authors' hospital. Ten cases of fatal chromosomal anomalies or major cardiac anomalies were excluded from this study. From 1988 through 1995 (period 1: n = 13), delayed surgery was used in high-risk CDH. From 1996 through 2000 (period 2: n = 17), early surgery in combination with iNO was used. The severity of lung hypoplasia was evaluated using the fetal lung/thorax transverse area ratio (L/T). High-frequency oscillatory ventilation (HFOV) was used routinely during the study periods, and extracorporeal membrane oxygenation (ECMO) was used on basis of conventional entry criteria. The authors compared the clinical outcome, use of ECMO, and the L/T between the 2 periods retrospectively.

RESULTS

Patients in the 2 periods were comparable in terms of birth weight, gestational age, and the L/T. The mean age at surgery was 3.1 +/- 4.9 days in period 1, and 0.8 +/- 1.1 days in period 2. Fewer infants in period 2 compared with period 1 were treated with ECMO (period 1, 62% v period 2, 6%; P <.01). There was significant difference in the survival rate between the 2 periods (period 1, 38% v period 2, 94%; P <.01).

CONCLUSION

Our data suggest that early surgery and iNO improves the outcome and reduces the requirement of ECMO in the treatment of antenatally diagnosed CDH.

Airway anomalies in patients with congenital diaphragmatic hernia

PURPOSE

Congenital diaphragmatic hernias (CDH) sometimes are associated with airway anomalies such as congenital stenosis, abnormal branching of the bronchi, and pulmonary hypoplasia. The incidence of these associated airway anomalies has not been reported previously.

METHODS

Bronchoscopy was performed in all neonates with CDH from 1987 to 1999. In addition to anatomic anomalies, bronchial hypoplasia was defined as narrowing and shortening of the bronchi at bronchoscopy.

RESULTS

Anatomic anomalies were identified in 7 of 39 patients with CDH: 1 had congenital tracheal stenosis with pulmonary artery sling, 1 had a defect of the right upper lobe bronchus, 2 had a tracheal bronchus, and 3 had a trifurcated trachea. Bronchial hypoplasia on the affected side was identified in 15 patients and was seen in all patients with anatomic anomalies of the tracheobronchial tree except the 2 with tracheal bronchus. After excluding 5 patients with severe associated anomalies, 6 of 14 patients with an abnormal tracheobronchial tree died, whereas 1 of 20 patients without airway abnormalities died.

CONCLUSIONS

Anatomic anomalies of the tracheobronchial tree and bronchial hypoplasia on the affected side were identified in 17.9% and 38.4% of patients with CDH, respectively. CDH patients who exhibited these abnormalities showed a poor outcome.

Congenital diaphragmatic hernia: a meta-analysis of mortality factors

PURPOSE

The aim of this study was to review all available studies reported in the English-language literature from 1975 through 1998, and by meta-analysis assess the importance of prenatal diagnosis, associated malformations, side of hernia, timing of surgery, and study population on mortality rates in patients with congenital diaphragmatic hernia (CDH).

METHODS

One-hundred-two studies were identified, and 51 studies (2,980 patients) fulfilled the prespecified inclusion criteria. Studies were grouped according to study population into: (I) fetuses diagnosed prenatally; (II) neonates admitted to a treatment center; and (III) population-based studies.

RESULTS

Pooled total mortality rate was significantly higher in category I than in category III (75.6% v 58.2%, P < .001). Pooled hidden postnatal mortality rate (deaths before admittance to a treatment center) in population-based studies was 34.9%. Prenatally diagnosed patients in both category II and III had significantly higher mortality rates than those diagnosed postnatally. Mortality rates were significantly higher among CDH infants with associated major malformations compared with isolated CDH in all 3 categories. An increased mortality rate in right-sided CDH was found in category II and III.

CONCLUSIONS

Prenatal diagnosis of CDH, presence of associated major malformations, and the study population have a major influence on mortality rate. The very high mortality rate in studies of fetuses with a prenatal diagnosis of CDH should be taken into account in prenatal counselling.