Effects of Umbilical Arterial Catheterization on Intestinal Hemodynamics

ABSTRACT

PURPOSE: An umbilical arterial catheter (UAC) in the high position reduces the lumen of the aorta and may thereby impair blood supply to the intestine. Effects of UAC on intestinal blood flow were investigated. METHODS: With the measurement of the aortic diameter, pulsed Doppler ultrasonography was performed in 23 fasting newborns to measure blood flow velocities (peak systolic velocity, end-diastolic velocity, mean velocity, time velocity integral and resistive index) in the celiac trunk (CT) and the superior mesenteric artery (SMA) before and after removal of the UAC in the high position. RESULTS: UAC reduced the cross-sectional area of the aorta by 3.5-15.0% (mean 7.5%), with the percentage of reduction being inversely related to birth weight (r=-0.86, P<0.0001). Blood flow velocities in the CT and the SMA did not change significantly after removal of the UACl left in place for 7 days. There were also no differences in blood flow velocities pre- and postremoval of the UAC which stayed in place for 17.3 days and caused a mean aortic obstruction of 11.7%. However, a longer indwelling time of the UAC may lead to a higher velocity in the CT with UAC in place, as reflected by a correlation by multiple regression analysis (r=0.42, P=0.045). CONCLUSION: Although UAC remaining in place for up to 2 weeks in fasting newborns does not lead to direct alterations in blood supply to the intestine, the possibility of blood flow impairment to abdominal organs by prolonged use cannot be excluded.