Partial amniotic carbon dioxide insufflation (PACI) during minimally invasive fetoscopic interventions on fetuses with spina bifida aperta.

BACKGROUND: Percutaneous partial amniotic carbon dioxide insufflation (PACI) is one of the most important means for improving visualization during minimally invasive fetoscopic surgery of fetal spina bifida. The purpose of the present study was to analyze maternal and fetal safety aspects of PACI in a recent patient cohort and to present management improvements.

METHODS: PACI under general materno-fetal anesthesia was performed during 65 interventions for fetoscopic patch coverage of fetal spina bifida aperta between 21 + 0 and 29 + 1 weeks of gestation. Filtered carbon dioxide was insufflated into the amniotic cavity via three percutaneously introduced trocars. Maternal ventilatory and hemodynamic parameters during PACI as well as insufflation pressures, BMI, parity, and placental position were recorded and statistically analyzed in order to detect potential risk groups.

RESULTS: Maternal respiration parameters during PACI showed a typical variation over time, which was similar in patients with BMI ≤ 25 or BMI > 25. The necessary insufflation pressures were significantly higher in nulliparae than multiparae. There was no statistically significant relationship between insufflation pressure and maternal BMI, or between the expired maternal carbon dioxide concentration (etCO2 ) and the placental position. PACI was safe for all mothers and fetuses. Postnatal demise in one neonate, one fetus, and two infants occurred unrelated to PACI and resulted from trisomy 13, infection, and severe Chiari II malformations, respectively.

CONCLUSION: PACI seems safe in order to improve visualization of intraamniotic contents during minimally invasive fetoscopic surgery. Nevertheless, continued assessments of its benefits and risks are important.