Gastrointestinal Physiology Before and After Duodenal Switch with Comparisons to Unoperated Lean Controls: Novel Use of the SmartPill Wireless Motility Capsule

Purpose Bariatric surgery alters gastrointestinal anatomy. In this exploratory study, the SmartPill (R) wireless motility capsule (WMC) was used to study changes in gastrointestinal physiology following biliopancreatic diversion with duodenal switch (BPD/DS). Material and Methods Twenty-eight BPD/DS patients (35 +/- 11 years, 50% females, body mass index [BMI] 56 +/- 5) were to be examined preoperatively and postoperatively. In addition to transit time, appetite control and gastrointestinal symptoms were studied by patient-scored questionnaires (visual analogue scale and Gastrointestinal Symptom Rating Scale (GSRS)). Data was compared to 41 lean unoperated controls. Results About 1.8 years postoperatively, 18 patients (BMI 35.8 +/- 8.3) returned for a second WMC test. As expected, small bowel transit time was reduced, from 3.9 +/- 1.6 h to 2.8 +/- 2.0, p = 0.02, and at both these time points, it was shorter than in lean controls (5.4 +/- 1.9 h, p = 0.001). Postoperatively, a trend towards reduced colon and whole gut transit times was seen in BPD/DS-patients, thus approaching those of lean controls. Surprisingly, BPD/DS patients scored higher satiety than controls preoperatively as well as increased hunger and desire to eat postoperatively. Compared to lean, BPD/DS patients reported a higher total GSRS score at both time points (1.2 +/- 0.2 vs 1.7 +/- 0.6 and 2.3 +/- 0.5, p < 0.001). Postoperatively, the scores for diarrhea and indigestion increased. Conclusions The novel use of the SmartPill system in BPD/DS patients gave the expected readouts. Although small bowel transit time was further shortened after BPD/DS, whole gut transit time did not differ from controls. Typical gastrointestinal symptoms were reported postoperatively.

Automated summary

The study utilized the SmartPill system to investigate changes in gastrointestinal physiology following biliopancreatic diversion with duodenal switch. Postoperatively, while small bowel transit time decreased, whole gut transit time did not differ from controls. Typical gastrointestinal symptoms were reported postoperatively.