Antenatal umbilical coiling index and Doppler flow characteristics

Autor: Frank A. Chervenak, Mladen Predanic, Sriram C. Perni
Rok vydání: 2006
Předmět:
Zdroj: Ultrasound in Obstetrics and Gynecology. 28:699-703
ISSN: 1469-0705
0960-7692
DOI: 10.1002/uog.2745
Popis: Objective To evaluate whether a relationship exists between the antenatal umbilical coiling index (UCI) and umbilical cord Doppler flow characteristics. Methods During the fetal anatomical survey in 200 consecutive pregnant patients at 18–23 weeks' gestation, we recorded umbilical coiling patterns and blood flow characteristics. The antenatal UCI, calculated as a reciprocal value of the distance between a pair of umbilical cord coils, was compared with Doppler parameters including umbilical vein blood flow volume (in mL/min/kg), and mean resistance index (RI) and peak systolic velocity (PSV in cm/s) averaged from both umbilical arteries. Results A total of 154 patients met the inclusion criteria of singleton pregnancy and having adequate sonographic umbilical cord images, Doppler flow indices, and all demographic, antenatal and labor data. The mean antenatal UCI was 0.40, with 10th and 90th centiles of 0.20 and 0.60, respectively. The mean ± SD umbilical artery RI and PSV and umbilical vein blood flow volume were 0.74 ± 0.07, 25.1 ± 6.4 cm/s, and 264 ± 106 mL/min/kg, respectively. All Doppler variables correlated significantly with antenatal UCI, with lower RI and higher PSV and umbilical vein blood flow volume values being associated with higher antenatal UCI (P = 0.016, P < 0.001, and P = 0.032, respectively). However, when stratified by antenatal UCI into hyper- (above 90th centile), normo- (10th–90th centile), and hypocoiled (below 10th centile) umbilical cord groups, a significant difference was observed for PSV only (P = 0.016). Conclusion It appears that umbilical cord coiling modulates noticeably blood flow through the umbilical cord. We speculate that more prominent umbilical coiling (higher antenatal UCI values) has a protective effect on blood flow in terms of decreased arterial resistance and higher blood flow velocities, as well as increased venous blood flow. However, due to lack of significant differences between Doppler characteristics when stratified by antenatal UCI into hypo-, normo-, and hypercoiled groups, the clinical implications of this observation are uncertain. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Databáze: OpenAIRE
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