Repeatability of Gastric Volume Measurements and Intragastric Content Using Ultrasound in Preterm Infants

Perrella, Sharon L.*; Hepworth, Anna R.*; Simmer, Karen N.; Hartmann, Peter E.*; Geddes, Donna T.*

Journal of Pediatric Gastroenterology & Nutrition: August 2014 - Volume 59 - Issue 2 - p 254–263
doi: 10.1097/MPG.0000000000000397
Original Articles: Gastroenterology

Objectives: The aim of the present study was to determine whether serial gastric volumes and intragastric curding are repeatable within individual preterm infants when given sequential feeds of the same volume and composition. Infant and feeding characteristics that may influence differences in measured gastric volumes, echogenicity, and intragastric curding were also explored.

Methods: Ultrasound images were used to calculate gastric volumes and to rate echogenicity and intragastric curding for 20 infants. A total of 29 paired feeds of the same volume and composition were monitored prefeed and postfeed and at 30-minute intervals thereafter. Statistical comparisons of paired gastric volume measurements and agreement between echogenicity and curding ratings were made for each time point. Analyses of factors that influence discrepancies between volume measurements and between curding ratings were performed.

Results: Paired gastric volume measurements were repeatable (intraclass correlation coefficient [ICC] = 0.971, 0.938 < ICC < 0.987). Most (75%) discrepancies were <2 mL and increased over time, although volume differences were small. Overall moderate levels of consistency were observed for ratings of echogenicity (κ = 0.44), and curd presence (κ ≤ 0.65), density (κ = 0.41), and volume (κ = 0.47). Gastric emptying during feed delivery is influenced with infant positioning, fortification of breast milk, and feeding frequency.

Conclusions: For preterm infants serial gastric volumes are repeatable and ratings of intragastric echogenicity and curding are moderately consistent when fed milk of the same volume and composition. Ultrasound has the potential to further explore factors that influence gastric emptying in the preterm infant.

*School of Chemistry and Biochemistry

Centre for Neonatal Research and Education, School of Paediatrics and Child Health, University of Western Australia, Crawley, WA, Australia.

Address correspondence and reprint requests to Sharon L. Perrella, MSc, M310, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia (e-mail: perres01@student.uwa.edu.au).

Received 8 December, 2013

Accepted 1 April, 2014

D.T.G. receives an unrestricted research grant from Medela AG.

The authors report no conflicts of interest.

© 2014 by European Society for Pediatric Gastroenterology, Hepatology, and Nutrition and North American Society for Pediatric Gastroenterology,