Predicting the risk of respiratory distress in newborns with congenital pulmonary malformations

Outcome of fetal congenital pulmonary malformations: a systematic review and meta-analysis

OBJECTIVES

To report the outcome of fetuses with a prenatal diagnosis of congenital lung malformation (CLM) diagnosed on ultrasound by performing a comprehensive assessment of these outcomes through a systematic review and meta-analysis.

CONTENT

CLMs are a heterogeneous group of anomalies that involve the lung parenchyma and its bronchovascular structures. Their presentation and evolution are variable, from entirely asymptomatic lesions with sonographic regression in utero to hydropic fetuses requiring fetal therapy, intrauterine death or neonatal morbidity. A systematic review was conducted in Medline, Embase and Cochrane databases including studies on fetuses with CLM diagnosed prenatally in order to report the in-utero natural history of these lesions. Thirty-nine studies (2,638 fetuses) were included in the final review.

SUMMARY

Regression/reduction in size of the lung lesion during pregnancy was reported in 31 % of cases, while its increase in 8.5 % of cases. Intra-uterine death complicated 1.5 % of pregnancies with fetal CLM, while neonatal and perinatal death were 2.2 and 3 %, respectively. Neonatal morbidity occurred in 20.6 % of newborns with CLM; 46 % had surgery, mainly elective. In fetuses with CLM and hydrops, fetal/perinatal loss occurred in 42 %. Assessment of the role of fetal therapy in improving the outcomes of pregnancies complicated by CLM was hampered by the small number of included cases and heterogeneity of type of interventions.

OUTLOOK

Fetuses with CLM prenatally diagnosed have a generally favorable outcome. Conversely, there is a low quality of evidence on the actual role of fetal therapy in improving the outcome of fetuses presenting with these anomalies.

Congenital lung malformations

Congenital lung malformations (CLMs) are rare developmental anomalies of the lung, including congenital pulmonary airway malformations (CPAM), bronchopulmonary sequestration, congenital lobar overinflation, bronchogenic cyst and isolated congenital bronchial atresia. CLMs occur in 4 out of 10,000 live births. Postnatal presentation ranges from an asymptomatic infant to respiratory failure. CLMs are typically diagnosed with antenatal ultrasonography and confirmed by chest CT angiography in the first few months of life. Although surgical treatment is the gold standard for symptomatic CLMs, a consensus on asymptomatic cases has not been reached. Resection, either thoracoscopically or through thoracotomy, minimizes the risk of local morbidity, including recurrent infections and pneumothorax, and avoids the risk of malignancies that have been associated with CPAM, bronchopulmonary sequestration and bronchogenic cyst. However, some surgeons suggest expectant management as the incidence of adverse outcomes, including malignancy, remains unknown. In either case, a planned follow-up and a proper transition to adult care are needed. The biological mechanisms through which some CLMs may trigger malignant transformation are under investigation. KRAS has already been confirmed to be somatically mutated in CPAM and other genetic susceptibilities linked to tumour development have been explored. By summarizing current progress in CLM diagnosis, management and molecular understanding we hope to highlight open questions that require urgent attention.

Serial lung mass volume ratios as prognostic indicators of neonatal respiratory morbidity in fetal pulmonary malformations

BACKGROUND

Several studies have shown that the congenital pulmonary airway malformation volume ratio is a useful prognosticator of neonatal outcome in prenatally diagnosed lung lesions. However, there remains a lack of consensus on which congenital pulmonary airway malformation volume ratio values have the best predictive value because of operator dependence, inherent changes in lung lesion size throughout gestation, and the widespread use of maternal steroids.

OBJECTIVE

This study sought to determine the association between serial congenital pulmonary airway malformation volume ratio measurements and neonatal outcomes among fetuses with lung malformations.

STUDY DESIGN

This was a retrospective cohort study of fetuses with a prenatally diagnosed lung malformation managed at 2 major fetal centers from January 2010 to December 2021. Prenatal variables, including prospectively measured congenital pulmonary airway malformation volume ratio measurements (initial, maximum, and final), were analyzed. The results were correlated with 3 outcome measures, namely surgical resection before 30 days of life, a need for supplemental O2 at birth, and endotracheal intubation at birth. Statistical analyses were performed using receiver operating characteristic curve analyses, Welch 2 sample t tests, and multivariable logistic regressions (P<.05).

RESULTS

There were 123 fetuses with isolated lung lesions identified. Eight (6.5%) had hydrops. The mean initial congenital pulmonary airway malformation volume ratio was 0.67±0.61 cm2 at 22.9±3.9 weeks' gestation. The mean maximum congenital pulmonary airway malformation volume ratio was 1.08 ± 0.94 cm2 at 27.0 ± 4.0 weeks' gestation. The mean final congenital pulmonary airway malformation volume ratio was 0.58±0.60 cm2 at 33.2±4.1 weeks' gestation. At a mean gestational age at delivery of 38.3±2.6 weeks, 15 (12.2%) underwent neonatal lung resection for symptomatic disease. In a multivariable regression, all 3 congenital pulmonary airway malformation volume ratio measurements showed a significant correlation with neonatal lung resection (P<.001). Optimal congenital pulmonary airway malformation volume ratio cutoffs were established based on an initial congenital pulmonary airway malformation volume ratio of ≥0.8 cm2, maximum congenital pulmonary airway malformation volume ratio of ≥1.5 cm2, and a final congenital pulmonary airway malformation volume ratio of ≥1.3 cm2 with associated areas under the curve of 0.89, 0.97, and 0.93, respectively. The final congenital pulmonary airway malformation volume ratio had the highest specificity for predicting surgical lung resection in the early postnatal period.

CONCLUSION

Measuring congenital pulmonary airway malformation volume ratios throughout pregnancy in fetuses with pulmonary malformations has clinical value for prenatal counseling and planning care transition after delivery. Fetuses with a final congenital pulmonary airway malformation volume ratio of more than 1.3 cm2 are likely to require neonatal surgery and therefore should be delivered at tertiary care centers with a neonatal intensive care unit and pediatric surgical expertise.

Impact of prenatal estimation of the risk of respiratory distress in neonates with congenital pulmonary malformations on the choice of delivery site

BACKGROUND

The vast majority of prenatally diagnosed congenital pulmonary malformations (CPM) remain asymptomatic at birth. The maximal value of the CPM volume ratio (CVRmax) predicts the risk of neonatal respiratory distress (NRD), and should allow for better assessment of the level of expertise needed at the delivery site.

AIM

This study evaluated the level of maternity units currently chosen for the delivery of CPMs, and determined the impact of the choice of delivery site based on the CVRmax, with a threshold of 0.4 cm².

METHODS

Data were extracted from the French prospective MALFPULM cohort, with inclusion between March 2015 and June 2018.

RESULTS

The final study population consisted of 383 women. Deliveries in level 1 or 2 maternity units (n = 98, 25%) involved CPMs with lower CVRmax (p<0.001), causing fewer signs of prenatal compression (p = 0.025). Among the 62 children (16%) who presented with NRD, only seven (11%) were born in level 1 or 2 units (p = 0.0078). Choosing the maternity level according to the CVRmax would have increased the number of births in level 1 or 2 maternity hospitals by 70%. In these maternity units, the percentage of children with NRD would have increased from 8% in the actual distribution to 10% in the new strategy.

CONCLUSION

Our results showed an overuse of level 3 maternity hospitals for the delivery of newborns with a prenatal diagnosis of CPM. The use of CVRmax should enable a reduction in the use of expertise centers without an adverse impact on newborns.

Can we predict the need for postnatal surgery in patients with prenatal fetal lung masses detected by CVR value?

AIM

The purpose of this study is to evaluate whether CPAM-volume ratio (CVR) can predict postnatal management (follow up for resolution and surgical treatment) in fetuses with fetal lung masses in the prenatal period.

MATERIALS AND METHODS

44 patients who presented at our center with prenatally diagnosed CPAM (Congenital Pulmonary Airway Malformation) and BPS (Bronchopulmonary Sequestration) were analyzed. Obstetric history and outcomes, karyotype results, CVR, additional sonographic findings, characteristics of masses were recorded. CVR was calculated for all cases. İn the study we sought to identify a CVR threshold and did not use the thresholds classically used in the literature.

RESULTS

20 fetal BPS and 24 CPAM cases were analyzed. After excluding 5 patients, 46% of the patients were diagnosed with BPS and 54% with CPAM. İn this study the cut off < 0,53 for CVR is taken, it predicts the no need for postnatal surgery with a sensitivity of 85% and a specificity of 88%. When we take the > 0,76 cut-off value for patients who will require emergency surgery within the first 10 days, it predicts the need for surgery with 90% sensitivity and 89% specificity. In addition, it was determined that all patients with mediastinal shift were operated.

CONCLUSION

We believe that the CVR value and the presence of mediastinal shift should be evaluated in all cases of CPAM and BPS for prediction of the surgery. Proper counseling about the prognosis could be given to the family in cases with mediastinal shift and CVR value above 0,76.