Oral Presentation Society of Obstetric Medicine of Australia and New Zealand and Australasian Diabetes in Pregnancy Society Joint Scientific Meeting 2017

Repeatability of USCOM®-measured cardiac output and systemic vascular resistance in normotensive non-pregnant and pregnant women (#25)

Jack G Mangos 1 , Rachel Preece 2 , Katie Harris 3 , Franziska Pettit 1 2 , Mark A Brown 1 2
  1. St. George and Sutherland Clinical School, University of New South Wales, Kogarah, NSW, Australia
  2. Department of Renal Medicine, St. George Hospital , Kogarah, NSW, Australia
  3. Centre for Big Data Research in Health, University of New South Wales, Kensington, NSW, Australia

Objectives: To investigate the repeatability of ultrasonic cardiac output monitor (USCOM) measurements of cardiac output and systemic vascular resistance in non-pregnant and normotensive pregnant women.

Study design: Cardiac output and systemic vascular resistance were measured, using the USCOM, five times successively within 5 minutes in non-pregnant (n = 34) and normotensive pregnant (n = 32) women of any gestation with uniform technique by a single operator. The data were analysed using multi-level modeling and intra-class correlations.  

Results: There was no statistically significant variation in either cardiac output or systemic vascular resistance with repeated measurement in non-pregnant or normotensive pregnant women. Intra-class correlations for cardiac output and systemic vascular resistance measurements were 0.921 (95% CI 0.887-0.947) and 0.934 (95% CI 0.905 – 0.956) respectively.

Conclusions: No extra information is added by making more than one USCOM measurement on the same woman under the same conditions in normotensive pregnant and non-pregnant women. The USCOM demonstrates excellent repeatability in this population. This finding should provide reassurance that single measurements using this system are of value in research and clinical practice.