A NONHUMAN PRIMATE MODEL FOR THE IN-UTERO CHRONIC CATHETERIZATION OF THE UMBILICAL VEIN

Short-term ultrasound-guided fetal umbilical cord catheterization in h umans has been reported. However, before chronic umbilical vein cathet erization is attempted in humans the technique must be tested in the n on-human primate model. If the fetus was to tolerate this procedure, c hronic fetal umbilical vein catheterization could be used for drug adm inistration, parenteral fetal nutrition or to monitor the changes of h ematologic parameters during and after open or endoscopic fetal surger y. In this study, 4 pregnant baboons were used to test the feasibility of ultrasound-guided umbilical vein catheterization. Although the umb ilical vein was successfully catheterized in all the animals, only 1 f etus survived the postoperative period. The 3 immediate fetal deaths w ere due to a fetal intraamniotic hemorrhage, while the most likely cau se of death of the 4th animal was infection. In the surviving fetus an d mother, blood was sampled once a day. Neither fetomaternal hemorrhag e nor thrombosis could be documented. We conclude that ultrasound-guid ed transplacental umbilical vein chronic catheterization is technicall y difficult but feasible in the baboon model. Further studies in this model are needed to improve the catheterization technique and to monit or the extent of time that the catheter may be tolerated within the um bilical vein.