Abstract

BACKGROUND Current breath tests for measurement of gastric emptying of solids are expensive, possibly inaccurate, and require cumbersome calculations.

AIMS We wished to validate a simplified solid gastric emptying test using a [¹³C]Spirulina platensisbreath test for accurate results relative to scintigraphy.

SUBJECTS Thirty healthy volunteers.

METHODS We measured gastric emptying of egg containing [¹³C]S platensis and^99mTc sulphur colloid by breath¹³CO₂ and scintigraphy over six hours. A generalised linear regression model was used to predict t_1/2 and t_LAG by scintigraphy from breath¹³CO₂ data. The model was cross validated and normative data calculated for a prepacked [¹³C]meal.

RESULTS Regression models using all breath data over six hours, for the first three hours, and for samples at 75, 90, and 180 minutes (“reduced model”) predicted t_1/2 and t_LAG values similar to scintigraphy (t_LAG 43 (SD 12) min; t_1/2 100 (20) min). Standard deviations of differences in t_1/2 and t_LAG between scintigraphy and the “reduced model” were both 10 minutes. Gastric t_1/2 for the prepacked [¹³C]meal was 91 (15) min (10–90% range: 74–118).

CONCLUSION The [¹³C]S platensis breath test and a simple formula using breath ¹³CO₂ at baseline, 90, and 180 minutes measured gastric emptying t_1/2 for solids with results that were comparable with scintigraphy.