Reducing the Deleterious Effects of Intrauterine CO2during Fetoscopic Surgery

Partial amniotic carbon dioxide insufflation (PACI) facilitates fetoscopic interventions in complicated monochorionic twin pregnancies

“…In contrast, during amniotic insufflation studies in sheep, carbon dioxide has resulted in fetal acidosis [2,4,5]. In our opinion, these studies bear little relevance for human fetal surgery because of the marked differences in placental anatomy between sheep and humans.…”

Minimally invasive fetoscopic interventions: an overview in 2010

“…2). Both technical and safety aspects of amniotic gas insufflation have been examined in sheep and humans, with conflicting safety results [15,[17][18][19][20][21][22][23]. Some investigators observed that in this species, carbon dioxide insufflation may result in fetal acidosis and demise.…”

Impact of partial amniotic carbon dioxide insufflation (PACI) on middle cerebral artery blood flow in mid‐gestation human fetuses undergoing fetoscopic surgery for spina bifida aperta

“…The Doppler-velocity-time-integrals in the middle cerebral artery before and within 2 min following deflation of the amniotic cavity were almost identical (Figure1), suggesting that fetal hypercarbia is unlikely. This observation may result because not much carbon dioxide is absorbed by the fetal skin and/or placenta during surgery and/or that the fetal concentration of carbon dioxide can be lowered effectively by maternal ventilatory adjustments 8 . Unfortunately, normal middle cerebral artery flow integrals may not prove sufficient oxygen delivery to the fetal brain because the cardiovascular and biophysical responses of a preterm fetus to induced hypoxemia may be less pronounced than those of older fetuses 9,10 .…”