Electrogastrography as a diagnostic tool for delayed gastric emptying in functional dyspepsia and irritable bowel syndrome

Several pathophysiological mechanisms have been proposed in functional gastrointestinal (GI) disorders, e.g. altered GI motility and sensitivity. The aim of this study was to investigate gastric electrical activity (GEA) in patients with functional dyspepsia (FD) or irritable bowel syndrome (IBS) compared with healthy controls (HC), and to assess if abdominal symptoms and delayed gastric emptying are associated with alterations in GEA, as determined by electrogastrography (EGG). Forty patients with FD, IBS or both were compared with 22 HC. EGG was performed before and after a standard meal. Frequencies and amplitudes pre- and post-prandially were analysed. Furthermore, gastric emptying and symptom scores were assessed. Eight of 40 patients (20%; three FD, three IBS, two FD and IBS) had delayed gastric emptying. Disturbed gastric emptying and lack of a postprandial increase in the EGG amplitude were significantly correlated (r = 0.8; P < 0.005). No differences between controls and patients were observed in the distribution of EGG frequencies. Treatment with the prokinetically active macrolide erythromycin improved gastric emptying, GEA and symptoms (n = 4). The data suggest that EGG could be useful as a diagnostic tool in patients with FD and IBS to identify a subgroup of patients with delayed gastric emptying.     

Electrogastrography for psychophysiological research: Practical considerations,analysis pipeline,and normative data in a large sample

Electrogastrography (EGG) is the noninvasive electrophysiological technique used to record gastric electrical activity by means of cutaneous electrodes placed on the abdomen. EGG has been so far mostly used in clinical studies in gastroenterology, but it represents an attractive method to study brain-viscera interactions in psychophysiology. Compared to the literature on electrocardiography for instance, where practical recommendations and normative data are abundant, the literature on EGG in humans remains scarce. The aim of this article is threefold. First, we review the existing literature on the physiological basis of the EGG, pathways of brain-stomach interactions, and experimental findings in the cognitive neuroscience and psychophysiology literature. We then describe practical issues faced when recording the EGG in young healthy participants, from data acquisition to data analysis, and propose a semi-automated analysis pipeline together with associated MATLAB code. The analysis pipeline aims at identifying a regular rhythm that can be safely attributed to the stomach, through multiple steps. Finally, we apply these recording and analysis procedures in a large sample (N = 117) of healthy young adult male and female participants in a moderate (<5 hr) to prolonged (>10 hr) fasting state to establish the normative distribution of several EGG parameters. Our results are overall congruent with the clinical gastroenterology literature, but suggest using an electrode coverage extending to lower abdominal locations than current clinical guidelines. Our results indicate a marginal difference in EGG peak frequency between male and female participants, and that the gastric rhythm becomes more irregular after prolonged fasting.     

胃电起搏治疗胃动力障碍疗效观察

目的: 通过观察胃动力障碍患者胃电起搏治疗前后症状及胃电节律变化情况,以评估胃电起搏治疗的疗效。方法: 对13例胃动力障碍患者行胃电起搏治疗,治疗前后进行症状评估及胃电图测定。结果: 13例胃动力障碍患者有明显的餐前餐后胃电节律紊乱,经胃电起搏治疗后症状有显著改善,总有效率为90.05%;治疗前后餐前正常慢波节律分别为(41.9±16.9)%和(46.9±21.6)%(P>0.05),治疗前后餐后正常慢波节律百分比分别为(57.5±28.6)%和(78.7±16.6)%(P<0.05)。结论: 胃电起搏治疗短期内能改善胃动力障碍患者的症状和胃电节律紊乱。     

小儿慢性胃炎体表胃电图检测

目的　通过体表胃电图描记了解小儿慢性胃炎胃肌电活动规律。方法　对 30例小儿慢性胃炎和 2 0例正常健康儿童进行餐前、餐后体表胃电图描记。结果　观察组较对照组餐后正常慢波百分比显著下降 [(60 3 %± 1 5 8% )vs(71 6 %±1 2 0 % ) ,P <0 0 5) ] ,餐前、餐后正常慢波百分比≥ 65 %所占比例下降无统计学意义 (63 .6 %vs70 .0 % ,P >0 0 5 ;50 .0 %vs70 .0 % ,P >0 0 5) ,餐后节律过缓 (<2 4/min)比例升高 ,但无统计学意义 [(1 8.4 %± 7.2 % )vs(8.5 %± 5 .3 % ) ,P >0 0 5) ] ;实验组胃电图波形奇异、不规则复合波多见。结论　小儿慢性胃炎存在胃电节律改变 ,表现为餐后正常慢波百分比显著下降。胃电图可应用于小儿慢性胃炎的初筛检查     

Multichannel electrogastrography under a magnifying glass – an in-depth study on reproducibility of fed state electrogastrograms

Abstract  We checked on reproducibility of parameters of a multichannel electrogastrogram in adults after intake of typical, applied in electrogastrography, test meals. Recordings of multichannel electrogastrograms were accomplished in four blocks comprising 18 subjects (nine healthy volunteers and nine patients with functional GI disorders) each. Every subject had two examinations taken 1-2 days apart, and a third one was accomplished at least 2 weeks before or after the two other sessions. The registration involved a 30-min fasted and a 2-h postprandial period after one of the meal stimuli tested within a given block: 400 mL water, 400 g yoghurt (378 kcal), a scrambled eggs sandwich (370 kcal), a pancake (355 kcal). From among the parameters reflecting the propagation of the gastric slow waves, the average percentage of slow wave coupling (APSWC) exhibited a good (coefficient of variation for paired examinations CV_p ≤ 10%) to moderate (10< CV_p ≤30%) reproducibility. On the other hand, the reproducibility of the maximum dominant frequency difference and the spatial dominant power difference was found to be unsatisfactory. The reproducibility of the multichannel electrogastrographic parameters did not differ between healthy volunteers and patients with functional GI disorders. Gender or the kind of a test meal did not affect the reproducibility of the electrogastrographic parameters either. The medium-term reproducibility was not any worse than the short-term one. From among the parameters of a multichannel electrogastrogram intended to quantify the propagation of slow waves, only the APSWC offers a reproducibility potentially good enough for clinical applications.     

腹腔镜与开腹胆囊切除术后胃肠动力恢复临床研究

目的:探讨腹腔镜胆囊切除与开腹胆囊切除术后胃肠动力恢复情况。方法:通过测定血浆胃动素、血清胃泌素、胃电图振幅、频率及术后腹压、肠鸣音恢复时间、肛门排气时间等几项指标联合观察了15例腹腔镜胆囊切除患者及15例开腹胆囊切除患者。结果:腹腔镜胆囊切除术组患者手术后胃动素、胃泌素、腹腔压力、胃电图振幅及慢波比率恢复要快于开腹胆囊切除术组。腹腔镜胆囊切除术组术后肠鸣音恢复时间及肛门排气时间也明显短于开腹胆囊切除术组。结论:腹腔压力的尽快恢复有益于胃肠动力的恢复,腹腔镜胆囊切除术后患者胃肠动力恢复较开腹胆囊切除术后快。     

肝硬化患者空腹胃动力障碍的临床研究

目的 :探讨肝硬化患者胃动力障碍发生率及其与肝功能的关系。方法 :运用体表胃电图观察 58例肝硬化患者和 2 2例健康人空腹胃肌电活动情况 ,观察指标包括平均振幅 ( AP)、平均过零频率 ( FZ)、中心频率 ( FC)、主频 ( FP)以及频谱形态。结果 :肝硬化患者胃电节律紊乱率明显高于健康组 ,其中 FZ分别为 38%和 50 % ;FP分别为 57%和 50 % ;Child- Pugh A组胃窦电节律紊乱率在 FP、FZ分别为 4 0 %和 2 0 % ;Child- Pugh B组分别为 61%和 32 % ;而 Child- Pugh C组则 10 0 %有胃窦节律异常。结论 :肝硬化患者电节律紊乱率较正常人明显升高 ,肝功能对胃电节律有影响     

新生儿胃电图与孕后年龄相关性的分析

目的 胃电图是应用表面电极进行经皮记录下的胃肌电活动情况。由于其具有非侵入性及与胃蠕动的相关性，而激起人们对胃电活动的兴趣，它对新生儿意义非同寻常。而新生儿胃电图资料不多且结果不一。本文欲探讨健康新生儿胃电活动与孕后年龄(胎龄 日龄)的相关性。方法 对23名健康早产儿住院期间每周记录1次胃电活动，19名足月儿分别进行1次胃电活动记录，共计61次。记录时间为餐前、餐后至少60分钟以及用餐时间。应用计算机化的胃电图参数进行分析，相关参数包括主频率(DF)，主频率在正常范围内的百分值(2～4CPM％)，主频率变异系数(DFIC)，餐后与餐前主频率能量比值(PR)。结果 我们未发现EGG参数值与孕后年龄的相关性。餐后2-4CPM％较餐前值显著下降(P=0．032)，餐后DF(P=0．26)，主频率能量(P=0．12)较餐前呈下降趋势，但是餐后DFIC较餐前有增加趋势。结论 在我们的研究中，通过胃电图我们没有发现胃电活动与孕后新生儿年龄的相关性。与其他资料结果相反，我们发现餐后DF，及主频率能量下降。即使胎龄小于35周的早产儿亦能产生胃电活动图形。总之，新生儿胃电图结果还存在许多矛盾之处，有待进一步探讨。     

Inhibitory effects of stress on postprandial gastric myoelectrical activity and vagal tone in healthy subjects

The aim was to investigate gastric myoelectrical activity (GMA) and vagal activity in response to stress. The study was performed in 10 healthy subjects in three sessions (control, relaxation and stress). The control session was composed of 30-min recordings before and 30-min recordings after a test meal. The protocol of two other sessions was similar except that the fasting recording was extended to 60 min and the subjects were continuously watching a horror movie (stress) or guided meditation tape (relaxation) after the 30-min baseline. GMA was recorded using electrogastrography and heart rate variability (HRV) was derived from the electrocardiogram. Meal resulted in a postprandial increase in the dominant frequency (2.91 cpm vs 3.17 cpm, P < 0.007), dominant power (30.0 dB vs 32.5 dB, P < 0.05), and percentage of normal slow waves (79.8%vs 87.4%, P = 0.09). Similar responses were found in the relaxation session. Stress inhibited all these normal postprandial response and reduced the regularity of gastric slow waves (82.0%vs 66.0%, P < 0.01). In addition, spectral analysis of the HRV demonstrated an inhibition of postprandial vagal activity and an increase of postprandial sympathetic activity with stress. Stress has an inhibitory effect on postprandial GMA and this may involve both vagal and sympathetic pathway.     

Influence of naloxone on gastric emptying of solid meals, myoelectrical gastric activity and blood hormone levels in young healthy volunteers

There is considerable evidence that opioid mechanisms are involved in the mediation of pyloric motor responses that in turn regulate gastric emptying. The purpose of this randomized, placebo-controlled crossover study was to investigate the effect of naloxone on gastric emptying of a solid meal, gastric myoelectrical activity and the postprandial release of gastrointestinal peptides and neuropeptides in 20 healthy volunteers. Naloxone was administered as an intravenous bolus, followed by continuous infusion according to an intravenous dosing nomogram. Gastric emptying time was evaluated by scintigraphy and gastric myoelectrical activity was evaluated by cutaneous electrogastrography. Naloxone did not significantly alter gastric half-emptying time and postprandial dominant gastric electrical frequency compared with placebo. It also did not significantly change the plasma levels of several peptide hormones with the exception of neuropeptide Y, which was significantly increased (P = 0.001). In conclusion, in doses that influence human intestinal motility, naloxone had no effect on gastric motility and release of several peptide hormones in healthy male volunteers. The importance of the isolated increased neuropeptide Y plasma level needs further investigation.