Prather, Charlene M.

The aim of this study was to assess the relationship between altered axial forces and gastric emptying of solids by experimentally inhibiting or stimulating gastric axial forces by intraduodenal lipid or intravenous erythromycin, respectively. In 15 healthy volunteers, we simultaneously measured gastric emptying of solids by scintigraphy, gastroduodenal motility by manometry, and forces along the longitudinal axis of the distal stomach by an axial force transducer. When 25% of the radiolabel had emptied from the stomach, subjects (n = 5 in each group) received normal saline (controls), intraduodenal lipid, or intravenous erythromycin. The test period consisted of the infusion period (10 min) and the subsequent 30 min. Lipid significantly reduced and erythromycin increased axial forces compared with control (lipid: median 0.6 N [0-1.4 interquartile range (IQR)]; erythromycin: median 18.2 N (16.5-20.5 IQR); control: median 4.7 N (3.9-5.2 IQR); P < 0.01). Similarly, antral phasic pressure activities were different relative to control. Gastric axial forces correlated significantly with gastric emptying (Spearman rank correlation = 0.86; P < 0.01). These data are consistent with the hypothesis that axial forces affect gastric emptying of solids and suggest that measurement of axial forces provides an assessment of overall gastric propulsion during the emptying of solids.

Our aim was to measure axial forces in the stomach and to evaluate their relation to circumferential contractions of the gastric walls and the emptying of gastric content. We used a combination of simultaneous radioscintigraphy, gastroduodenal manometry, and an axial force transducer with an inflatable 2-ml balloon fluoroscopically placed in the antrum. In vitro studies demonstrated that the axial force transducer records only antegrade forces along the longitudinal axis of this probe in an intensity-dependent manner. In vivo studies were performed in five healthy subjects for at least 3 h after ingestion of radiolabeled meals. When administered separately, the emptying of liquids or solids from the stomach is associated with generation of antral axial forces and coincident phasic pressure activity; however, almost 20% (average) of gastric axial forces during emptying of liquids or solids are unassociated with proximal or distal antral pressure activity ("isolated" forces). High amplitude antral axial forces and pressures occur during both lag and postlag emptying phases. During emptying of liquids, there is a trend for axial forces to be coincident more often with proximal than with distal antral pressure activity and vice versa for the emptying of solids (P = 0.015). These data suggest that when placed in the antrum, the transducer can semiquantitatively record axial forces during gastric emptying. By combining these observations with the data from in vitro studies, it appears that axial forces predominantly result from traction on the balloon by the longitudinal vector resulting from circumferential gastric contractions. The combination of radioscintigraphy and measurement of antral axial forces is a promising method to evaluate mechanical forces involved in the emptying of the human stomach.

SummaryBackgroundFunctional dyspepsia (FD), a common functional gastrointestinal disorder, is defined by the Rome III criteria as symptoms of epigastric pain or discomfort (prevalence in FD of 89–90%), postprandial fullness (75–88%), and early satiety (50–82%) within the last 3 months with symptom onset at least 6 months earlier. Patients cannot have any evidence of structural disease to explain symptoms and predominant symptoms of gastroesophageal reflux are exclusionary. Symptoms of FD are non‐specific and the pathophysiology is diverse, which explains in part why a universally effective treatment for FD remains elusive.AimTo present current management options for the treatment of FD (therapeutic gain/response rate noted when available).ResultsThe utility of Helicobacter pylori eradication for the treatment of FD is modest (6–14% therapeutic gain), while the therapeutic efficacy of proton pump inhibitors (PPI) (7–10% therapeutic gain), histamine‐type‐2‐receptor antagonists (8–35% therapeutic gain), prokinetic agents (18–45%), tricyclic antidepressants (TCA) (response rates of 64–70%), serotonin reuptake inhibitors (no better than placebo) is limited and hampered by inadequate data. This review discusses dietary interventions and analyses studies involving complementary and alternative medications, and psychological therapies.ConclusionsA reasonable treatment approach based on current evidence is to initiate therapy with a daily PPI in H. pylori‐negative FD patients. If symptoms persist, a therapeutic trial with a tricyclic antidepressant may be initiated. If symptoms continue, the clinician can possibly initiate therapy with an anti‐nociceptive agent, a prokinetic agent, or some form of complementary and alternative medications, although evidence from prospective studies to support this approach is limited.