Polyhydramnios Secondary to Esophageal Atresia – Cervical Cerclage and Serial Amnioreduction to Prolong Gestational Age in Select Cases (2024)

ABSTRACT

Esophageal atresia (OA) with or without tracheoesophageal fistula affects approximately 1 in 4000 births and commonly presents with polyhydramnios. This appears to be the first report regarding the utility of cervical cerclage with serial amnioreduction to prolong the gestational age of a neonate with OA, thereby improving outcomes for reconstructive surgery.

KEYWORDS: Amnioreduction, cervical cerclage, esophageal atresia, polyhydramnios

INTRODUCTION

Esophageal atresia (OA) with or without tracheoesophageal fistula (TOF) affects approximately 1 in 4000 births. Polyhydramnios has been observed in approximately 95% of neonates with pure OA and 35% of neonates with distal TOF. It is associated with preterm labor among other complications. This case study reviews the utility of cervical cerclage with serial amnioreduction to prolong the gestational age (GA) of a neonate with OA by 8 weeks and 1.37 kg weight increment. This translated into good neonatal outcomes after successful reconstructive surgery. This seems to be the first such effort.

CASE REPORT

A well 35-year-old primiparous female presented with ultrasound findings of polyhydramnios at GA of 29 weeks. Her pregnancy was booked early and noninvasive prenatal testing was low risk. Her fetal anomaly scan at GA 20 weeks was reported normal; however, at GA 29 weeks, transabdominal ultrasound detected polyhydramnios and an absent fetal stomach bubble raising suspicion for OA. The estimated fetal weight then was 1196 g and cervical length was shortened to 1.78 cm. The mother was asymptomatic aside from abdominal fullness with no other symptoms of threatened pregnancy. Amniocentesis was performed and DNA extraction results had no clinical significance. The consulting obstetrician recommended cervical cerclage with amnioreduction to prolong gestation. The mother was counseled regarding associated risks and underwent an operation uneventfully. Intraoperatively, cervical length was 1 cm, confirming initial ultrasound findings. The mother subsequently underwent serial ultrasonography and a total of four amnioreductions at two weekly intervals with fluid removal of 2L–2.5 L each time [Table 1]. The case was discussed with a multidisciplinary board and consensus was made for term delivery with pediatric surgery and neonatal team on standby. She underwent elective cesarean section and cerclage removal at GA 37 weeks and 3 days.

The neonate was born at 2.66 kg with an Apgar score of 9 and 9 at the 1^st and 5^th min, respectively. A nasogastric tube was unable to advance beyond the T2 vertebral level and an X-ray showed distal bowel gas, indicative of Type C TOF [Figure 1]. A Replogle tube was inserted for upper pouch suction and the neonate was transferred to the intensive care unit (ICU). VACTERL screening detected a large patent ductus arteriosus, and moderate fenestrated atrial septal defect but no other fetal abnormalities.

On day 2 of life, the neonate underwent primary repair of the Type C TOF. Bronchoscopy with size-8 Parsons laryngoscope discovered a large fistula opening at the carina [Figure 2], mild tracheomalacia and no laryngeal cleft. On thoracotomy, the distal TOF was identified, ligated, and the tracheal defect closed. The initial gap between the upper pouch and distal TOF was 4 cm. Careful mobilization of the above structures was performed and primary single anastomosis was done. Postoperatively, the neonate was monitored in ICU and an esophagogram 6 days later showed a patent anastomosis with no leak. The patient was discharged well on day 17 of life after establishing oral feeds.

DISCUSSION

Antenatal diagnosis and timely treatment for polyhydramnios are crucial to optimize outcomes for neonates with OA. About 77.8% of neonates with OA present with polyhydramnios on antenatal ultrasound. This is occasionally associated with a small or absent stomach bubble (22.2% and 25.9%, respectively).[1] Polyhydramnios can result from maternal diabetes, infection, and fetal anomalies among others.[2] Fetal gut atresia, specifically OA, has been linked to polyhydramnios due to impaired fetal swallowing and fluid absorption affecting the regulation of amniotic fluid volume. If severe, polyhydramnios can lead to premature rupture of membranes, abnormal fetal lie, and increased rates of prematurity and perinatal mortality.[2]

On presentation, the mother although asymptomatic was at high risk for preterm delivery. Based on the consulting obstetrician’s clinical judgment and counseling with parents, a decision was made for a two-step operation; cervical cerclage and amnioreduction. In view of a fetal anomaly of OA, the aim was to optimize fetal growth and lung maturity for definitive surgery as prematurity is associated with increased cardiovascular and respiratory risks while very low birth weight is associated with higher postoperative complication rates as well as making surgery technically difficult.

In the literature, there is no consensus for the ideal timing of cerclage and it is usually performed between 12 and 28 weeks. Meta-analysis has not revealed a significant reduction of preterm birth for cerclage done after 24 weeks.[3] In addition, risks of cervical cerclage include infection, rupture of membranes, surgical site lacerations, and anesthesia-related complications. However, given the high risk of neonatal morbidity if born premature, after careful consideration of risks and benefits, the team together with the parents, decided to proceed with cerclage to optimize the likelihood of prolonging GA.

Amnioreduction is classically performed for symptomatic severe polyhydramnios with amniotic fluid index ≥35 cm or single deepest pocket ≥16 cm and has shown benefits in providing maternal symptomatic relief.[2] Some studies have also demonstrated benefits in prolonging gestation.[4] Associated complications include preterm rupture of membranes, preterm delivery, placenta abruption, and chorioamnionitis; however, these risks are low in singleton pregnancies.

Amniocentesis should be considered as neonates with OA are associated with VACTERL, CHARGE, DiGeorge syndrome, and trisomies 13, 18, and 21 among others. The diagnosis of the above syndromes should be considered when counseling parents for invasive procedures given a guarded prognosis.

A 2019 case series by Zhang et al. documented eight patients who underwent amnioreduction as an adjunct to cervical cerclage for cervical incompetence with benefits in prolonging GA.[5] With fetal OA, polyhydramnios will likely to recur hence close monitoring with repeated amnioreductions may prove beneficial. In our experience, both interventions were integral in prolonging gestation, thereby optimizing conditions for successful reconstructive surgery.

CONCLUSIONS

Antenatal management of OA is not often discussed as antenatal diagnosis is difficult. However, in selected cases of neonates with OA presenting with polyhydramnios and threatened preterm delivery, cervical cerclage with repeated amnioreduction may be a safe and efficacious treatment in prolonging GA, improving outcomes for postnatal reconstructive surgery. More research should be done to establish efficacy.

Acknowledgement

The contribution of the following individuals is sincerely appreciated. Dr June Tan Vic Khi and Dr Anju Bhatia were responsible for assisting fetal procedures, collecting antenatal data and the antenatal follow up. They provided valuable data points for the above write up and are gratefully acknowledged.

REFERENCES