Sonja Brennan1,1, David Watson2,2, Michal Schneider3, Donna Rudd4, Yogavijayan Kandasamy5,5,5. 1. Ultrasound Department, Townsville University Hospital, Douglas, Townsville, Australia. 2. Division of Tropical Health and Medicine, James Cook University, Townsville, Australia. 3. Maternal Fetal Medicine Unit and Department of Obstetrics and Gynaecology, Townsville University Hospital, Townsville, Australia. 4. Department of Medical Imaging & Radiation Sciences, Monash University, Melbourne, Australia. 5. Department of Neonatology, Townsville University Hospital, Townsville, Australia.
Abstract
INTRODUCTION: The study objectives were to develop standard charts for fetal renal artery blood flow to define normal ranges and to assess the reliability of the measurements. METHODS: This prospective, longitudinal study reviewed 72 low-risk singleton pregnancies who had serial ultrasound examinations. Pulse wave Doppler was used to obtain the resistivity and pulsatility indices of the fetal renal arteries. Standard charts of the fetal renal arteries were created using mixed effects modelling and the intra- and interobserver reliability for the renal blood flow measurements was analysed. RESULTS: Standard charts of the normal ranges of the renal artery resistive index (RI) and pulsatility index (PI) of the fetal renal arteries were created. The 3rd, 5th, 10th, 50th, 90th, 95th and 97th centiles were calculated. The intraclass correlation coefficient was acceptable for intraobserver reliability (RI = 0.66, PI = 0.88) and poor for interobserver reliability (RI = 0.11, PI = -0.56). CONCLUSIONS: These novel charts demonstrate the change of the fetal renal artery blood flow during pregnancy. These may be used in clinical practice to detect variations from these normal ranges and be useful in future studies of kidney function projection.
INTRODUCTION: The study objectives were to develop standard charts for fetal renal artery blood flow to define normal ranges and to assess the reliability of the measurements. METHODS: This prospective, longitudinal study reviewed 72 low-risk singleton pregnancies who had serial ultrasound examinations. Pulse wave Doppler was used to obtain the resistivity and pulsatility indices of the fetal renal arteries. Standard charts of the fetal renal arteries were created using mixed effects modelling and the intra- and interobserver reliability for the renal blood flow measurements was analysed. RESULTS: Standard charts of the normal ranges of the renal artery resistive index (RI) and pulsatility index (PI) of the fetal renal arteries were created. The 3rd, 5th, 10th, 50th, 90th, 95th and 97th centiles were calculated. The intraclass correlation coefficient was acceptable for intraobserver reliability (RI = 0.66, PI = 0.88) and poor for interobserver reliability (RI = 0.11, PI = -0.56). CONCLUSIONS: These novel charts demonstrate the change of the fetal renal artery blood flow during pregnancy. These may be used in clinical practice to detect variations from these normal ranges and be useful in future studies of kidney function projection.
Authors: Camilla O Figueira; Fernanda G Surita; Márcia S J Dertkigil; Simiran L Pereira; João R Bennini; Sirlei S Morais; José G Cecatti Journal: Int J Gynaecol Obstet Date: 2015-07-07 Impact factor: 3.561