Impaired gastric slow waves induced by spatial disorientation and effect of domperidone

OBJECTIVES: Our aims were to investigate the dominant frequency and regular ity of gastric myoelectrical activity during motion sickness induced with t he advanced spatial disorientation demonstrator (ASDD) and to evaluate the effect of domperidone on gastric myoelectrical activity and gastrointestina l symptoms during motion sickness. METHODS: Thirteen healthy volunteers participated in this study. This study was executed using the ASDD, which could duplicate several spatial disorie ntation phenomena in a safe, controlled environment. Each subject participa ted in two sessions and received oral administration of 10 mg domperidone b efore the study in one of the sessions. In each session, three 15-min EGG r ecordings were made before, during, and after rotation. The symptoms were s cored by Graybiel's scale of motion sickness before and after rotation. All EGG data were subjected to computerized spectral analysis to obtain the pe rcentage of normal 2-4 cycles/min (cpm) slow waves, percentage of tachygast ria, EGG dominant frequency and power, and instability coefficient of the d ominant frequency. RESULTS: We have found that the percentage of normal gastric slow wave was decreased (control session: 86.2 +/- 4.0% vs 70.0 +/- 5.4%, p < 0.01; dompe ridone session: 82.7 +/- 4.6% vs 69.8 +/- 5.6%, p < 0.03) and the percentag e of tachygastria was increased (control session: 8.7 +/- 3.2% vs 17.8 +/- 5.6%, p < 0.01; domperidone session: 9.2 +/- 3.3% vs 18.1 +/- 3.5%, p < 0.0 1) after rotation in both sessions. The minute-by-minute variation of the g astric slow wave frequency was significantly increased during rotation in b oth sessions (control: 0.74 +/- 0.16 vs 1.35 +/- 0.19, p < 0.01; domperidon e: 0.90 +/- 0.20 vs 1.47 +/- 0.17, p < 0.01). Domperidone did not prevent d ysrhythmia or the symptoms of motion sickness. CONCLUSIONS: The percentage of normal gastric slow waves is decreased and t he percentage of tachygastria is increased with spatial disorientation. Dom peridone does not prevent gastric dysrhythmia or the symptoms of motion sic kness induced with spatial disorientation. (C) 1999 by Am. Cell. of Gastroe nterology.