Improved use of the [C-13]octanoic acid breath test as intra-individual parameter to study the effect of a prokinetic drug on gastric emptying in preterm infants with oral feeding intolerance

The [C-13]octanoic acid breath test was used for the measurement of differe nces in gastric emptying in preterm infants for the evaluation of pharmacol ogical therapy. In order to perform a good intra-individual comparison of t he gastric emptying in preterm infants under non-standardisable test condit ions, we adjusted t(1/2) for variations in non-recovered label (=label rete ntion) and introduced an "effective half (CO2)-C-13 breath excretion time" t(1/2eff)=t(1/2)/m expressed as min per percentage of the cumulative dose r ecovered. In a pilot study, we investigated the action of the gastrointesti nal prokinetic drug cisapride on gastric emptying in seven premature infant s, of whom four suffered from gastric stasis and three had constipation. Th e postnatal age and weight at the start of treatment ranged from 15 to 64 d ays and from 815 to 1635 g, respectively. All infants received the standard formula for premature infants (Nenatal, Nutricia). Cisapride was administe red orally 0.2 mg/kg, four times daily. The changes in gastrointestinal mot ility were studied using the total bowel transit time of carmine red. After 7 days of treatment in all children, the gastric emptying coefficient and the half (CO2)-C-13 breath excretion time adjusted for label retention were improved (n=7, the gastric emptying coefficient range before treatment was 1.69-3.34 (mean 2.59+/-0.80) and after treatment it was 2.79-3.76 (mean 3. 28+/-0.30); the half (CO2)-C-13 breath excretion time adjusted for label re tention range before treatment was 3.0-14.7 min/% dose (mean 7.0+/-5.0) and after treatment 2.6-4.0 min/% dose (mean 3.1+/-0.6). The total bowel trans it time was only slightly improved in two patients (n=7, mean total bowel t ransit time before: 23.7 h compared to mean total bowel transit time after 7 days of treatment: 35.5 h). Side effects during cisapride treatment were not seen. We conclude that in premature infants cisapride is effective in s hortening gastric emptying time and reducing gastric stasis; the therapeuti c role in constipation has to be further investigated. (C) 2001 Elsevier Sc ience B.V. All rights reserved.