A pilot study of ultrasound evaluation of gastric emptying in patients with end-stage renal failure: a comparison with healthy controls.

This prospective study was designed to evaluate gastric volume and content in patients with renal failure and healthy controls after an overnight fast, immediately after a light meal and at 6 h after the meal. Thirty subjects in each group were recruited. At each scanning session, gastric antral cross-sectional area was measured in the supine recumbent and right lateral decubitus positions, and a qualitative assessment of gastric contents was made using the Perlas three-point grading system. Six hours after the meal, the mean (SD) antral cross-sectional area in the supine position was 471 (195) mm2 in patients with renal failure and 319 (106) mm2 in healthy controls (p = 0.028), whereas in the right lateral position it was 756 (320) and 521 (180) mm2 , respectively (p = 0.21). In terms of the qualitative assessments of gastric contents, all subjects had an empty stomach after an overnight fast. Five patients with renal failure and no controls had Perlas grade 2 images, indicating significant gastric contents, 6 h after a meal (p = 0.026). This study supports the use of bedside gastric ultrasound as a point-of-care test for patients with known risk factors for delayed gastric emptying.