title: Fetal cardiac intervention: improved results of fetal cardiac bypass in immature fetuses using the TinyPump device.
abstract: OBJECTIVE
  Fetal cardiac surgery is a potential innovative treatment for certain congenital heart defects that have significant mortality and morbidity in utero or after birth, but it has been limited by placental dysfunction after fetal cardiac bypass. We have used the TinyPump device for fetal cardiac bypass in sheep fetuses at 90 to 110 days gestation.
  
  
  METHODS
  Ten mixed-breed pregnant ewes were used over a period of 6 months, and 10 fetuses were placed on bypass for 30 minutes. Five fetuses with a mean gestational age of 104 ± 4.5 days and mean weight of 1.4 ± 0.4 kg were placed on bypass using the TinyPump device, and 5 fetuses with a mean gestational age of 119 ± 4.5 days and mean weight of 3.4 ± 0.4 kg were placed on bypass using the roller head pump. The fetuses were monitored for up to 3 hours after bypass or until earlier demise.
  
  
  RESULTS
  Progressive respiratory and metabolic acidosis developed in all fetuses. The TinyPump group had a lower gestational age and weight compared with the roller head pump group. However, the rate of postbypass deterioration in the TinyPump group, as measured with blood gases, was noted to be significantly slower compared with the roller head pump group.
  
  
  CONCLUSIONS
  We demonstrate the feasibility of the TinyPump device for fetal cardiac bypass in a fetal sheep model. The TinyPump group showed improved results compared with the roller head group despite more immature fetuses. The TinyPump device seems to be a promising device for future studies of fetal cardiac bypass in immature fetal sheep and in primates.
authors.affiliation: Division of Pediatric Cardiac Surgery, Lucile Packard Children's Hospital, Stanford University School of Medicine, Stanford, Calif 94305, USA. vinodas@yahoo.com
authors.forename: Vinod A
authors.initials: VA
authors.lastname: Sebastian
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ferro
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kagawa
authors.forename: Teimour
authors.initials: T
authors.lastname: Nasirov
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Maeda
authors.forename: William T
authors.initials: WT
authors.lastname: Ferrier
authors.forename: Setsuo
authors.initials: S
authors.lastname: Takatani
authors.forename: R Kirk
authors.initials: RK
authors.lastname: Riemer
authors.forename: Frank L
authors.initials: FL
authors.lastname: Hanley
authors.forename: V Mohan
authors.initials: VM
authors.lastname: Reddy
mesh_terms: D000818:Animals; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D005260:Female; D005318:Fetal Heart / Q000601:surgery*; D006353:Heart-Assist Devices; D011247:Pregnancy; D011256:Pregnancy Outcome; D012756:Sheep