Fig 1.
Illustration of the analysis and typically reported time points in gastric emptying.
Lag Time (Tlag; time to maximal 13CO2 excretion), and half time (T1/2; the time it takes 50% of the 13C dose to be excreted) DOB: Delta Over Baseline (percentage of 13CO2 recovered). cPDR: cumulative Percentage Dose Recovered.
Table 1.
Patient characteristics and questionnaire evaluation.
Fig 2.
Exhaled breath analysis for assessment of gastric emptying in 32 patients.
The median (IQR) changes over baseline of 13C enrichment (Delta over baseline, DOB) in exhaled air after ingestion of the test meal are shown along with the cumulative percentage dose recovered (cPDR). The vertical dashed lines (patients on PPV: long dashed vertical line at 183 minutes; spontaneously breathing patients: short dashed vertical line at 201 minutes) indicate the median time to recovery of 50% cumulative dose. It was considerably longer than the half time of normal controls (solid vertical line at 107 minutes).[31]
Table 2.
Gastrointestinal and colonic transit.
Fig 3.
Oro-cecal transit assessed by exhaled breath analysis in 33 patients.
The median (IQR) changes over baseline of isotopic enrichment in exhaled breath generated by the 13C enriched test meal are shown. Median oro-cecal transit time was similar in spontaneously breathing (370 minutes; no positive pressure ventilation; no PPV)) and mechanically ventilated (378 minutes; with positive pressure ventilation; with PPV) patients and considerably longer than in healthy controls (solid vertical line at 295 minutes).[25]
Fig 4.
Representative radiograph of the abdomen.
This is a representative radiograph of a not acutely ill, 38 year old patient with Duchenne muscular dystrophy. Radiopaque markers and extensive meteorism are seen in the colon. Rods and screws (one of them displaced) for spinal stabilization and a PEG tube are visible.
Table 3.
Spearman correlation analysis.