Pulmonary Effects of Prolonged Oligohydramnios following Mid-Trimester Rupture of the Membranes – Antenatal and Postnatal Management

Abstract

Mid-trimester, preterm prelabour rupture of the membranes (PPROM) with prolonged oligohydramnios remains a challenge for both obstetricians and neonatologists. Although survival rates have improved, morbidity remains common particularly due to pulmonary insufficiency and pulmonary hypertension. The aetiology of abnormal lung development is unknown but may depend critically on pulmonary vascular development. Antenatal evaluation of at-risk foetuses by three-dimensional ultrasound and MRI is possible but the techniques need to be further assessed. Antenatal corticosteroids given in cases of PPROM reduce the incidence of neonatal death, respiratory distress syndrome, intraventricular haemorrhage and necrotising enterocolitis without increasing maternal or neonatal infection. The true risk-benefit ratio of antibiotics, tocolysis and strategies to normalise amniotic fluid volume remains less clear. There is no consensus regarding the optimal ventilation strategy to support infants with pulmonary insufficiency following PPROM, and further work is required to determine whether and which pulmonary vasodilators improve long-term outcome in these infants.

Neonatal Survival After Prolonged Preterm Premature Rupture of Membranes Before 24 Weeks of Gestation

“…[11][12][13][14] This feared complication occurs in an estimated 10-20% of neonates after preterm PROM. Pulmonary hypoplasia consists of dysplastic lung parenchyma and altered pulmonary vasculature.…”

Thrown off balance: the effect of antenatal inflammation on the developing lung and immune system

“…44 Moreover, the importance of amniotic fluid/fetal lung fluid for human fetal lung development has been well described. 45,46 Despite these developmental advantages of large animals over rodents, rodent models offer the possibility to use transgenic approaches to study candidate genes in the pathogenesis of IA inflammation/infection. 35,[47][48][49] Therefore, both animal models are useful to study the effects of intraamniotic infection/inflammation on lung development.…”

Antenatal diagnosis and management of life-limiting conditions

“…The aetiologies of such a problem can be varied: for example, very preterm membrane rupture can cause leakage of the amniotic fluid, leading to prolonged oligohydramnios or anhydramnios. 55 The other common cause is obstructive or dysplastic renal tract pathology, preventing either adequate drainage or production of fetal urine, thereby contributing to oligohydramnios. Lower urinary tract obstruction due to posterior urethral valves or urethral agenesis is often evident on the first trimester scan, manifesting as a dilated bladder.…”