RESUMEN
OBJECTIVES: To evaluate peak systolic velocity (PSV) in the umbilical artery (UA) among patients with single umbilical artery (SUA) as compared with patients with three vessel cords. METHODS: A prospective case-control study was performed. UA blood flow velocimetry was obtained from fetuses with SUA and from a control group with three vessel cord. PSV and pulsatility index (PI) were measured. Patients' characteristics were compared for statistical differences and a linear regression model was constructed for the different groups. RESULTS: UA Doppler velocimetry measurements were obtained from 29 patients with SUA and from 29 controls matched for gestational age. The differences between UA PI with and without SUA were significant (F = 3.471; p = 0.0379) showing a lower PI in the SUA group. However, no significant statistical difference was found in PSV between these two groups (F = 0.149; p = 0.86). CONCLUSIONS: While the impedance in the UA of patients with a SUA was lower compared with patients with a normal umbilical cord, the PSV did not differ.
Asunto(s)
Arteria Umbilical Única/fisiopatología , Adulto , Velocidad del Flujo Sanguíneo , Estudios de Casos y Controles , Femenino , Peso Fetal , Humanos , Recién Nacido , Embarazo , Ultrasonografía Doppler , Ultrasonografía Prenatal , Arterias Umbilicales/fisiología , Arterias Umbilicales/fisiopatología , Adulto JovenRESUMEN
PURPOSE: To evaluate blood flow Doppler velocimetry during the first and second stages of active labor. METHODS: A prospective observational study was performed. Patients at term (37-42 weeks gestation), with normal fetal heart rate tracing patterns (categorized as category I) were examined during the first and second stages of labor. The sonographic parameters that were measured included the blood flow resistance of the maternal uterine artery (UtA) and umbilical artery (UA). Wilcoxon-matched pair test was used for the comparison of flows between the first and the second stages of labor. RESULTS: UtA and UA Doppler velocimetry measurements were obtained from 31 parturients. The left (LT) and right (RT) UtA pulsatility index (PI) was lower in the second stage of labor as compared with the first stage. However, only the LT side reached a statistically significant difference (0.88 ± 0.32 and 0.73 ± 0.18; P = 0.005). Compared with the first stage of labor, UA PI was significantly higher during the second stage of labor (0.72 ± 0.17 vs. 0.84 ± 0.33; respectively, P = 0.05). CONCLUSION: Significant blood flow resistance changes in maternal as well as in fetal blood vessels occur during the second stage as compared with the first stage of active labor.
