Continuous amnioinfusion via a subcutaneously implanted port system with PPROM and anhydramnios < 28+0 weeks of gestation: an international prospective randomized trial

Mid-trimester PPROM occurs in 1% of pregnancies leading to a high neonatal mortality and morbidity rate, causing extreme preterm birth combined with the “fetal inflammatory response syndrome” (FIRS), thus inducing lung hypoplasia.

Purpose: The evaluation of continuous amnioinfusion therapy joining a 7 day lasting antibiotic treatment with PPROM and oligo-/anhydramnios (SDP = single deepest pocket < 2 cm) between 22+0 until 27+6 weeks of gestation compared to the antibiotic therapy appropriate to national guidelines is the objective of this prospective randomized trial.

Material and methods: 48 patients will participate in this study, divided into an intervention or control goup, each containing 24 women. Entry criteria: Singleton pregnancies, classic PPROM and proven oligo/- anhydramnios between 22+0 to 27+6 weeks of gestation. Exclusion criteria: fetal chromosomal aberrations, malformations, high PPROM, AIS, premature labour. The comparison of both groups regarding the PPROM-delivery-latency in days and appearance of FIRS will be the primary endpoint of this investigaton. The ultrasound-based subcutaneous implantation of the port system is conducted in local anaethesia. A hypotonic amniotic fluid-like solution (100 ml/h) is used for permanent amnioinifusion (J Perinat Med 2013;41:657 – 63).

Results: An earlier retrospective analysis showed a significant prolongation of the PPROM-delivery-interval for 49 days and a better neonatal outcome without lung hypoplasia or contractures, applying continuous amnioinfusion with 2.4 litres/day (“flush-out”).

Conclusion: Flushing-out bacteria and inflammatory products out of the amniotic cavity could extend pregnancy, prevent lung hypoplasia and improve neonatal outcome clearly. This assumption is to be verified in this study. Patient recruitment shall be completed by the end of 2017.

Several physicians from 5 countries have been instructed in the method of port implantation at the Center of Fetal Surgery, University Clinic of Obstetrics and Prenatal Medicine, Martin-Luther- University Halle-Wittenberg.

Sponsoring: Center of Fetal Surgery, University Hospital Halle (Saale) and Russian Science Foundation, Grant- Nr. 15 – 15 – 00137.