Sonographic evaluation of maternal blood loss after childbirth using postpartum inferior vena cava diameter among parturients in Kano Metropolis, Nigeria

Abstract

Postpartum hemorrhage has been a major cause of maternal morbidity and mortality globally every year. Sonographic measurement of inferior vena cava diameter is a cheap, safe, non-invasive method and an indicator of blood loss after childbirth. The study was aimed to establish normal range values of postpartum inferior vena cava (IVC) among parturients in Kano metropolis, Nigeria. A prospective and longitudinal study from September, 2021 to September, 2022 was adopted and a minimum sample size of 210 measurements of IVC intraluminal diameter was calculated for the study using G Power sample size software. The sample comprised of two sets measurements obtained from 105 parturients before delivery and after delivery. The maternal heart rate and systolic blood pressure were measured. Blood samples from all subjects were collected. The data was analyzed using IBM Statistical Software. The range value of IVC diameter on inspiration of the subjects before childbirth was 13.2 mm – 20.3 mm, after childbirth was 9.1 mm – 16.7 mm. The IVC diameter range on expiration before childbirth was 17.3 mm – 24.8 mm, after childbirth was 12.6 mm – 21.4 mm. The Packed Cell Volume (PCV) range of the subjects before childbirth was 35% – 40%, after childbirth was 18% – 33%. The heart rate before childbirth was 64 bpm – 100 bpm, after childbirth was 70 bpm – 100 bpm. The systolic blood pressure before childbirth was 110 mmHg – 120 mmHg, after childbirth was 90 mmHg – 120 mmHg. The shock index before childbirth was 0.5 – 0.9 and after childbirth was 0.6 – 0.9. A statistical significant (p<0.001) difference in IVC was observed. Furthermore, a statistical significant (p<0.001) difference was obtained in PCV, maternal heart rate, systolic blood pressure and shock index. There was a statistical significant strong positive correlation between IVC and PCV during inspiration and expiration before and after childbirth.