Value of inferior vena cava diameter and inferior vena cava collapse index in the evaluation of peripartum volume: A prospective cohort study

Abstract

ObjectiveThe maternal intravascular volume status assessed during and after gestation is valuable but challenging due to the influence of the substantial adaptive cardiovascular changes during pregnancy. The present study aimed to investigate the changes in the size of inferior vena cava (IVC) diameter and collapse index (IVC-CI) during perinatal delivery and whether it is affected by the change in intravascular volume during delivery. Study designA total of 31 full-term, singleton, and cephalic delivery women delivered by vagina with an estimated blood loss of >500 mL measured longitudinally between September 2019 and September 2020 in the Department of Obstetrics and Gynecology of The Third Hospital in China. The end-expiratory (IVCe) and end-inspiratory (IVCi) diameters of the inferior vena cava were measured at the first, second, and third stages of labor (T1, T2, and T3, respectively) and postpartum haemorrhage ≥500 mL (T4 and after rapid rehydration 500 mL (T5). The collapse index of IVC was calculated, and blood pressure and heart rate were measured. ResultsIVCe and IVC-CI changed significantly in a volume-dependent manner during the perinatal period (T1–T5; P < 0.05). IVCe narrowed significantly with volume reduction (after postpartum hemorrhage) and widened significantly with volume increase (after volume resuscitation). IVC-CI increases significantly with decreased capacity and decreases significantly with increased capacity. ConclusionThe width and collapse index of IVC reflect the circulatory volume changes during the parturient’s perinatal period with postpartum hemorrhage.