A valid, accurate, oYce based non-radioactive test for gastric emptying of solids

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 [C]Spirulina platensis breath test for accurate results relative to scintigraphy. Subjects—Thirty healthy volunteers. Methods—We measured gastric emptying of egg containing [C]S platensis and Tc sulphur colloid by breath 13CO2 and scintigraphy over six hours. A generalised linear regression model was used to predict t1/2 and tLAG by scintigraphy from breath 13CO2 data. The model was cross validated and normative data calculated for a prepacked [C]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 t1/2 and tLAG values similar to scintigraphy (tLAG 43 (SD 12) min; t1/2 100 (20) min). Standard deviations of diVerences in t1/2 and tLAG between scintigraphy and the “reduced model” were both 10 minutes. Gastric t1/2 for the prepacked [ C]meal was 91 (15) min (10–90% range: 74–118). Conclusion—The [C]S platensis breath test and a simple formula using breath 13CO2 at baseline, 90, and 180 minutes measured gastric emptying t1/2 for solids with results that were comparable with scintigraphy. (Gut 2000;46:768–773)