OC03.04: Brain oxygen saturation during umbilical cord cannulation in a fetal lamb model of artificial placenta system

To evaluate the variations in brain regional oxygen saturation during umbilical cord cannulation in lamb fetuses transferred to an artificial placenta (AP) system. Experimental study including a consecutive sample of 9 lamb fetuses at 95-125 gestational days (term 145 days), undergoing umbilical cord cannulation and transfer to an AP system. Brain regional oxygen saturation (rSO2) was measured by near-infrared spectroscopy (NIRS) before (native placenta), during and after (AP) umbilical cord cannulation. Delta-values were calculated for the three stages. Surgical time, pH and lactate after cannulation, and complications (blood loss, vasospasm, decannulation, bubbles and vessel injury) were also recorded. A total of 3 (33.3%) male and 6 (66.7%) female fetuses of 117 ± 5.8 days gestational age were successfully cannulated. Occlusion time (between first vein occlusion until connection of the first artery) was 230 ± 65.4 seconds, and total cannulation time was 385.6 ± 132 seconds. rSO2 was 33.8 ± 16.5%, 22.8 ± 12.9% and 40.1 ± 14.5%, before, during and after cannulation respectively. Brain rSO2 was higher in the AP system compared to native placenta (p < 0.001). Complications occurred in 4 animals, being blood loss the most frequent (44.4%). In subjects who experienced blood loss, there was a drop in saturation of 3.2 ± 7.1% after AP connection compared to an increase of 14 ± 11.6% in subjects without (p = 0.04). In fetal lamb model, umbilical cord cannulation was associated with preserved brain perfusion regardless of cannulation time. A transient decrease of rSO2 during cannulation was followed by a slight increase after connection to the AP system. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.