Abstract
BACKGROUND AND AIMS: Functional nausea is an idiopathic gastrointestinal disorder that is common in children, carries a substantial health-care cost, and lacks objective diagnostic testing, relying primarily on symptomatology with an otherwise normal diagnostic workup. We hypothesize that high-resolution electrogastrogram (HR-EGG) spatiotemporal gastric slow wave parameters, reflective of known mechanisms of gastric uncoupling, are sensitive to nausea severity and can distinguish children with severe functional nausea when asymptomatic, from healthy pediatric controls. METHODS: We compared nonrandomized fasted HR-EGG recordings from control subjects (N = 10; 11-17 years; 3 M/7F) with recordings from functional nausea patients (N = 10; 12-18 years; 1M/9F) with inactive nausea at time of testing but had experienced nausea in the preceding 2 weeks. We used a second-order blind identification algorithm to minimize signal artifacts, identify gastric sources, and calculate spatiotemporal gastric slow wave frequency and propagation dynamics. RESULTS: Frequency dynamics showed significant differences between controls and patients in dominant frequency (2.7 ± 0.5 cycles per minute vs 2.2 ± 0.5 cycles per minute; P < .01), percentage of signal distribution in the normogastric range (59 ± 11.8% vs 46.5 ± 11%; P < .001), and bradygastric power percentage (20 ± 10.5% vs 28.1 ± 9.5%; P < .01). Propagation dynamics observed in patients were more complex and disordered, with significant differences in mean propagation direction (control: 223° ± 23°; patient: 20° ± 79°; P < .05), and propagation speed (P < .01). CONCLUSION: We demonstrate that spatiotemporal analysis of HR-EGG propagation profiles differentiates pediatric functional nausea patients from controls. Given the high incidence of anxiety in children with functional nausea, future investigations should explore the influence of state and trait anxiety on HR-EGG parameters via the gut-brain axis.