Electrogastrography in Healthy Children Evaluation of Normal Values, Influence of Age, Gender, and Obesity

Electrogastrography (EGG) is a reliabletechnique to record gastric electrical activity.However, the normal values of electrical activity inchildren and the effects of age, gender, and body massindex (BMI) are not well defined. To evaluate theseitems, EGG signal was picked up before and after a mealin 114 healthy children (age range: 6-12 years) by meansof a pair of cutaneous electrodes sonographically placed on the abdominal surface. The dominantfrequency was prevalently found in the 2.0-4.0 cpm range(P < 0.001). A significant difference was foundcomparing the pre- and postprandial instability coefficient of dominant frequency (P <0.05). The EGG power increased postprandially (powerratio = 3.6), and the power ratio was not correlated tothe approach of the wall of the gastric antrum to the abdominal surface (Spearman r = 0.0045,NS). In obese children, the postprandial pattern inresponse to a mixed test meal containing carbohydrate asthe major caloric source was similar to that recorded in normal-weight children. EGG parameters werenot affected by age and gender apart from a significantdifference in the postprandial instability coefficientobtained from the girls 9 years groupcompared to the girls <9 years andboys 9 years groups (P < 0.05). Inconclusion, in children 6-12 years old, EGG parametersare not affected by BMI in response to a mixed testmeal. Gastric electrical rhythm and rate, and gastric power are notinfluenced by age and gender, whereas the instabilitycoefficient seems to be influenced by these factors. Thenormal values of the EGG parameters evaluated in this study should be introduced in the analysisof gastric electrical activity for an effectiveinterpretation of the EGG signal from children withfunctional or organic diseases.     

Multichannel Electrogastrography (EGG) in Normal Subjects: A Multicenter Study

The aim of this study was to record gastric myoelectric activity using multichannel electrogastrography (EGG) and to determine if there are differences due to age, gender, body mass, and study location. In 61 normal subjects from four centers, fasting multichannel EGG was recorded for 1 h, followed by two 1-h postprandial recordings after a test meal. Variables assessed included dominant frequency (DF) and its power, percentage time in 2- to 4-cpm frequency, and percentage slow-wave coupling (%SWC). There were no significant differences in EGG parameters with respect to gender or age. Subjects with a BMI >25 had a decrease in the absolute DF power but a similar increase in the postprandial DF power. Subjects with a BMI >25 had a postprandial decrease in the %SWC compared to those with a BMI <25. There was a decrease in postprandial %SWC in European/Asian centers compared to American centers. In conclusion, multichannel EGG provides assessment of electrical slow-wave coupling in addition to determining dominant frequency, power, and percentage normal rhythm. This multicenter study of normal subjects shows similar multichannel EGG values among different genders and ages. Body mass and ethnicity may impact on some of the EGG values.     

Electrogastrography prior to and following total gastrectomy,subtotal gastrectomy,and gastric tube formation

On electrogastrography (EGG) spectral analysis, an activity of 3 cycles per minute (cpm) is supposed to be specific for the stomach. After total or subtotal gastrectomy, the original site of the stomach is occupied mainly by the intestine. We attempted to determine if intestinal activity could be recorded in this region with EGG. Epigastric recordings were performed in patients prior and following gastrointestinal or control surgeries. Spectral analysis, using the maximal entropy method and ensemble means was applied to data analysis from these recordings. Preoperatively, the majority of the power peaks were found around 3, 6, and 11 cpm. The postprandial-to-fasting power ratio of all of these power peaks increased significantly postprandially (P<0.05–0.01). Following total gastrectomy, the power peak around 3 cpm disappeared or was significantly diminished in amplitude (P<0.05). The postoperative-to-preoperative power ratio ranged from 0.03 to 0.10 (P<0.001–0.01). However, the power peak around 11 cpm did not significantly change prior to or following total gastrectomy, and the 11 cpm peak appeared relatively dominant. Simultaneous manometric studies in the Roux limb demonstrated a correlation between the power spectral frequency of EGG and manometry at 11 cpm. Therefore, the 11 cpm peak appeared to reflect jejunal or Roux limb electrical activity. The postoperative to preoperative power ratio for the 3 cpm also was significantly reduced following subtotal gastrectomy and gastric tube formation in patients in the postprandial state (P<0.05–0.001).     

Electrogastrographic characteristics in subjects with stomach remnant

Background and Aims: Slow wave (SW) is an essential component in mediating stomach motility. The purpose of the present study was to investigate the SW characteristics in subjects with stomach remnant. Methods: We consecutively enrolled 58 distal radical subtotal gastrectomy (RSG) patients (male/female: 44/14, age: 33–79 years) to receive an electrogastrographic (EGG) measurement. Their Helicobacter pylori status and dyspeptic score were simultaneously assessed. In addition, EGG data of 58 age‐ and sex‐matched healthy subjects were compared. Based on power spectral analysis, the following EGG parameters were derived: dominant frequency (DF)/power (DP), percentage of normal rhythm (2–4 cpm), power ratio (PR) referring the postprandial power change, etc. Results: Visual analysis occasionally found a short period of ～11 cpm myoelectricity‐like rhythm. Distal RSG patients had lower fasting (1.90 ± 0.69 vs 2.97 ± 0.58 cpm, P < 0.001) and postprandial (2.03 ± 0.72 vs 3.35 ± 0.27 cpm, P < 0.001) DF values, while their fasting (36.2 ± 22.3% vs 67.1 ± 23.4%, P < 0.001) and postprandial (33.4 ± 19.9% vs 82.2 ± 16.7%, P < 0.001) percentages of normal rhythms were diminished. In contrast, fasting DP, its meal response and PR (2.99 ± 2.40 vs 2.45 ± 2.63, NS) were comparable to those of controls. Neither gender, age, type of gastroenterostomy, Helicobacter pylori colonization, dyspeptic score nor elapsed time after surgery had an obvious influence on EGG parameters. Conclusions: Distal RSG patients may have decreased SW frequency and less meal ingestion changed EGG parameters in terms of SW frequency, normality and stability, whereas their EGG power remained unchanged irrespective of meal ingestion.     

Antral Myoelectric Activity,Gastric Emptying,and Dyspeptic Symptoms in Diabetics

Background: Electrogastrography (EGG) enables the cutaneous measurement of gastric electric activity. An association between electric abnormalities and gastrointestinal motility disorders has been shown. The primary objective of this study was to investigate whether diabetic gastroparesis could be predicted by EGG.

Methods: EGG was performed in 18 insulin-treated type-II diabetics (9 female, 9 male; median age, 64 years; range, 45-76 years) with chronic dyspepsia. After an overnight fast, during 1 h in the fasting and 1 h in the fed state after ingestion of a liquid-solid test meal (370 kcal; liquid phase labeled with 0.5 mCi ^99mTc-colloid) antral electric activity was captured by one pair of electrodes sonographically placed on the skin overlying the gastric antrum. Several EGG variables including dominant frequency (DF), percentages of DF in the normal range (24 cycles per minute (cpm)), bradygastria (<2cpm), and tachygastria (4-10 cpm), dominant frequency instability coefficient (DFIC), and postprandial to preprandial power ratio (PR) were calculated by fast Fourier transform. The data were correlated to results obtained in 20 age- and gender-matched healthy subjects (10 female, 10 male; median age, 68 years; range, 53-90 years). In addition, the data were compared with the percentages of retention of the radionuclide in the stomach at 60 min, and lag times measured by simultaneous scintigraphy.

Results: The EGG values obtained in diabetics did not differ significantly from those in healthy subjects and did not correlate with radioscintigraphy (p > 0.05). Moreover, the EGG values in diabetics with delayed gastric emptying (about 40%) did not differ from data in diabetics without gastroparesis. Furthermore, whereas dyspepsia correlated significantly with radioscintigraphy, no correlation with EGG could be found.

Conclusions: Electrogastrography seems to be unsuitable for assessment of motility disorders in type4 diabetics.     

Electrogastrography associated with symptomatic changes after prokinetic drug treatment for functional dyspepsia

AIM:To evaluate the effect of prokinetic drugs on electrogastrography(EGG) parameters according to symptomatic changes in patients with functional dyspepsia(FD).METHODS:Seventy-four patients with FD were prospectively enrolled in this study between December 2006 and December 2010.We surveyed the patients using a questionnaire on dyspeptic symptoms before and after an 8-wk course of prokinetic drug treatment.We also measured cutaneous pre-prandial and postprandial EGG recordings including percentage of gastric waves(normogastria,bradygastria,tachygastria),dominant frequency(DF),dominant power(DP),dominant frequency instability coefficient(DFIC),dominant power instability coefficient(DPIC),and the ratio of post-prandial to fasting in DP before and after the 8-wk course of prokinetic drug treatment.RESULTS:Fifty-two patients(70%) achieved symptomatic improvement after prokinetic drug treatment.Patients who had normal gastric slow waves showed symptom improvement group after treatment.Postprandial DF showed a downward trend in the symptom improvement group,especially in the itopride group.Post-prandial DP was increased regardless of symptom improvement,especially in the itopride group and mosapride group.Post-prandial DFIC and DPIC in the symptom improvement group were significantly increased after the treatment.The EGG power ratio was increased after treatment in the symptom improvement group(0.50 ± 0.70 vs 0.93 ± 1.77,P = 0.002),especially in the itopride and levosulpiride groups.CONCLUSION:Prokinetics could improve the symptoms of FD by regulating gastric myoelectrical activity,and EGG could be a useful tool in evaluating the effects of various prokinetics.     

Gastric Dysrhythmias and Delayed Gastric Emptying in Patients with Functional Dyspepsia

An association between dyspepsia, gastricmotility disorders, and myoelectrical abnormalities hasbeen noted. The objective of the present study was toinvestigate both antral myoelectrical activity and gastric emptying in patients with functionaldyspepsia (FD). Electrogastrography (EGG) was performedin 25 adult patients with FD, which had been evaluatedby score. After an overnight fast, for 1 hr in the pre- and postprandial state (370 kcalliquid-solid test meal) the following EGG parameterswere determined: dominant frequency [DF (cpm)], DF (%)in the normal range (2-4 cpm), bradygastria (<2 cpm), tachygastria (4-10 cpm), dominant frequencyinstability coefficient (DFIC), and postprandial tofasting power ratio (PR). The data were correlated toresults obtained in 20 age- and gender-matched controls. In addition, in 17 consecutive patients the EGGdata were compared to the gastric retention ofradionuclides after 60 min (liquid-solid phase labeledwith ^99mTc colloid). Patients with FDrevealed a preprandial increase in tachygastria compared to controls(P < 0.001). Of 17 FD, seven patients exhibiteddelayed gastric emptying (t60 retention >68%). Thesepatients showed significantly more pre- and postprandial tachygastrias than patients with normal gastricemptying (P < 0.05). The dyspeptic symptology and H.pylori status did not correlate with EGG andradioscintigraphy. Patients with FD frequently revealimpaired gastric emptying and increased tachygastria,which may have pathophysiological significance in someof these patients.     

Multichannel electrogastrography (EGG) in symptomatic patients: a single center study

OBJECTIVES: To determine the value of multichannel versus conventional single-channel electrogastrography (EGG) and of an additional postprandial hour recording in symptomatic patients. METHODS: Eighteen normal subjects and 47 patients with upper GI symptoms underwent multichannel EGG with four cutaneous recording electrodes placed on the antral axis. Fasting EGG was recorded for 1 h, followed by meal ingestion, followed by two 1-h postprandial EGG recordings. Variables assessed: (1) dominant frequency (DF) and its power; (2) percent time in normal (2-4) cpm frequency; (3) average percent of slow wave coupling (% SWC). RESULTS: Normal values for single-channel EGG were: (1) DF from 2.5-3.3, 2.7-3.5, and 2.6-3.5 cpm in the fasting, first, and second postprandial hours; (2) percentage of time in 2-4 cpm: >50%, >65%, and >65% in the fasting, first, and second postprandial hours. Normal values for percent SWC using multichannel EGG were >50%, >55%, >55% in the fasting, first, and second postprandial hours. In the symptomatic patients, an abnormal 2-h single-channel EGG was obtained in 16 of 47 (34%) patients. Adding an additional 1 h of postprandial recording identified another 4 abnormal patients (20/47 = 43%). With multichannel EGG, abnormal results were obtained in 24 of 47 patients (51%) with the 2-h study. An additional 1 h of postprandial recording identified another 4 patients as abnormal (28/47 = 60%). CONCLUSIONS: Multichannel EGG recording improved the detection of abnormal gastric myoelectric activity in symptomatic patients. This study also demonstrates prolonging the postprandial recording to 2 h increases the diagnostic yield for both single-channel and multichannel EGG.     

Gastric myoelectrical activity and gastric emptying in patients with functional dyspepsia

OBJECTIVES: The aims of this study were to investigate gastric myoelectrical activity and gastric emptying (GE) and their relationship in patients with functional dyspepsia. METHODS: The study was conducted in 15 healthy volunteers (six women, nine men, mean age: 42 yr) and 15 patients (13 women, two men, mean age: 43 yr) with functional dyspepsia. Gastric myoelectrical activity was recorded using cutaneous electrogastrography (EGG) for 30 min in the fasting state and for 120 min simultaneously with GE monitoring after an isotope-labeled solid meal. The anterior/posterior images of the stomach were taken using a technetium scanner immediately after eating, and then at 1, 2, and 4 h to determine the percentage of gastric retention. The dominant frequency of the EGG, the change of the postprandial EGG peak power (deltaP), and the percentage of normal 2-4 cycles/min (cpm) slow waves during each recording session were calculated and compared between the patients and healthy subjects. RESULTS: The patients had a significantly lower mean percentage of 2-4 cpm slow waves, both in the fed state and in the fasting state, than did healthy subjects. Compared to the EGG in the fasting state, a significant increase of the EGG dominant frequency in the fed state was observed in healthy subjects but not in the patients. The mean postprandial EGG power increase in the patients was substantially less than in the healthy subjects during the first postprandial hour but similar during the second postprandial hour. The mean percentage of gastric retention in patients is substantially higher than in the healthy subjects, both at 2 h after eating and at 4 h after eating. Of 15 patients, nine (60%) had delayed GE (gastric retention at 2 h >50%) and 10 (66%) had abnormal EGGs (percentage of 2-4 cpm <70% and/or deltaP < 0). Eight of these 10 patients (80%) with abnormal EGGs had delayed GE. CONCLUSIONS: A high proportion of adult patients (60%) with functional dyspepsia have abnormally slow GE and abnormalities in gastric myoelectrical activity.     

Gestational Maturation of Electrical Activity of the Stomach

Gestational maturation of gastrointestinalmotility is a key factor in readiness of the pretermneonates for enteral nutrition. Since gastric motilitymainly depends on the electrical activity of the smooth muscle cells, it was of interest to investigatethe developmental aspects of electrical activity of thestomach. The latter was recorded weekly throughcutaneous electrogastrography in 27 preterm infants (aged 29-34 weeks of gestation). Recordingswere done for 1 hr before and 1 hr after meal. Theelectrogastrographic variables measured were: percentageof normal gastric rhythm, i.e., 2-4 cpm; percentage of tachygastria (>4 cpm); the fed-to-fastingratio of the dominant electrogastrographic power; andthe instability coefficient of the dominant frequency.Data were compared with those measured in 10 full-term infants. Peaks of normal electricalactivity (2-4 cpm) were present in most of therecordings at all the gestational ages; however,percentages of both normal electrical rhythm andtachygastria in preterm infants were similar to thosemeasured in full-term infants (mean ± SD) (normalrhythm; fasting: 70.2 ± 3.8, fed: 72.2 ±5.0; tachygastria: fasting: 24.6 ± 4.0, fed: 19.1± 3.5) by 35 weeks of gestation (normal rhythm; fasting:67.5 ± 2.0, fed: 69.6 ± 4.4; tachygastria:fasting: 27.1 ± 4.0, fed: 25.6 ± 4.1). Thecoefficient of instability of the dominant frequency inpreterm infants was also similar to the value measuredin full-term infants by 35 weeks of gestation, whereasthe EGG power showed a significant increase in thepostprandial state at all the gestational ages. We conclude that a maturation pattern of theelectrical activity of the stomach can be detected bymeans of a noninvasive tool such as cutaneouselectrogastrography: a normal electrical rhythm can bedetected at very early gestational ages; however, thisactivity becomes dominant at around the 35 weeks ofgestational age. In preterm infants developmentalchanges of gastric electrical activity are a function of advancing postnatal age.     

Electrogastrography in Patients with Chagas' Disease

Electrogastrograghy (EGG) was performed in 33 patients with Chagas' disease and in 15 healthy volunteers—control group. The EGG was performed in two different periods: in fasting and postprandial. The EGG was submitted to a continuous spectral analysis. The following parameters were evaluated: % dominant frequency in spectral bands: normogastria (2–4 cpm), bradygastria (1–2 cpm), tachygastria (4–10 cpm) and duod/resp (10–15 cpm). EGG was considered normal if normogastria > 65% in both EGG periods. The chagasic group showed % normogastria significantly lower (basal, P < 0.01), % bradygastria (basal, P = 0.01) and % tachygastria (basal and postprandial, P =.001) significantly higher than the control group. EGG was normal in 14/15 (93%) in control group × 16/33 (53%) in chagasic group (P < 0.05). It was concluded that: 1) the prevalence of gastric dysrhythmias was higher in chagasic patients than in comparison to a control group 2) gastric dysrhythmias may be considered one of the abnormalities presented in the chagasic gastropathy.     

Inhibitory effects of cholecystokinin on postprandial gastric myoelectrical activity

While a number of studies have investigated the effects of cholecystokinin (CCK) on gastrointestinal motility, little is known on the effects of CCK on gastric myoelectrical activity, which regulates gastric motility. The aim of this study was to investigate the effects of intravenous infusion of CCK-8 on gastric myoelectrical activity in normal humans. Gastric myoelectrical activity was measured in 10 healthy subjects with a noninvasive electrogastrographic technique by placing abdominal electrodes on the epigastric area. Two study sessions were performed in each subject on two separate days with double-blinded infusion of either saline or CCK (24 pmol/kg/hr). The procedure for each session was as follows: (A) 30-min baseline fasting electrogastrogram (EGG); (B) start infusion, another 30-min EGG; (C) give meal, 60-min EGG; and (D) stop infusion, another 60-min EGG. The dominant frequency and peak power (amplitude) of the EGG, and the percentage of normal 2–4 cycles/min slow waves during each recording session were computed and compared between placebo and CCK. It was found that normal 3 cpm slow waves were recorded in all EGGs. Infusion of CCK had no effect on the frequency of the gastric slow wave and did not induce gastric dysrhythmias. It was also found that intravenous infusion of CCK significantly decreased the EGG peak power (amplitude) during the first hour after the meal (the infusion was given during this period) in comparison with placebo (P<0.05). This inhibitory effect on EGG peak power was sustained but not significant during the second postprandial hour (the infusion was not given during this period). It was concluded that intravenous infusion of CCK at a physiological concentration significantly decreased the postprandial EGG amplitude in normal humans, suggesting an inhibitory effect on postprandial gastric motility, but did not change the frequency and regularity of the gastric slow wave.     

Gastric involvement in systemic sclerosis: a prospective study

OBJECTIVES: This study aims to assess the prevalence of gastric electrical activity dysfunction with cutaneous electrogastrography (EGG), disturbances of gastric emptying function using radiopaque pellets, and gastric endoscopic abnormalities in patients with systemic sclerosis (SSc). We also investigate for an association between EGG and gastric-emptying data with clinical manifestations and esophageal motor disturbances. METHODS: Fasting and postprandial gastric electrical activity was studied in 22 consecutive patients with SSc (17 with and 5 without clinical gastric manifestations) and 22 age- and sex-matched healthy subjects. Gastric emptying of radiopaque pellets and gastroscopy were also performed in SSc patients. RESULTS: The prevalence of EGG disturbances was as high as 81.82% in SSc patients. SSc patients exhibited, compared with controls, higher median percentage of dominant frequency in bradygastria during the fasting period and lower median values for postprandial electrical power and postprandial to fasting ratio for electrical power. Gastric emptying of radiopaque pellets was delayed in 11 SSc patients, and gastroscopy demonstrated "watermelon stomach" in 3 SSc patients. No correlation was found between the severity of gastric impairment and clinical presentation, SSc duration and subsets, and esophageal manometric impairment. CONCLUSIONS: Our study underlines the high frequency of gastric dysfunction in SSc patients. It suggests the usefulness of EGG in SSc in noninvasively detecting disorders of gastric electrical activity at an early stage and symptomatic patients with gastroparesis (because there was a correlation between values of postprandial to fasting ratio for electrical power of < 1 on EGG and delayed gastric emptying). Gastric-emptying evaluation of radiopaque pellets may further be a helpful method to depict symptomatic SSc patients with gastroparesis. Finally, our series confirms that watermelon stomach diagnosis should be excluded in SSc patients presenting with gastrointestinal hemorrhage or with anemia related to iron deficiency.     

Real-time display of the stomach slow wave and its parameters in a newly designed electrogastrographic system

We designed a new three-channel electrogastrographic (EGG) system, which was easily operated on the Windows 95 platform and could automatically provide slow wave parameters. The purpose of the present study was to test its reliability and accuracy in clinical recording. The system included a signal acquisition device assembled on a printed circuit board. Recorded myoelectrical signals were filtered, amplified, digitized, and transmitted via this device into a notebook personal computer (PC). Based on the short-term Fourier transform the software could transfer the time domain of the signal into the frequency domain. Real-time displayed slow wave parameters, including dominant frequency/power, percent of normal frequency (2–4 cpm), instability coefficient in frequency/power, and power ratio, were automatically renewed every 64 s. Twenty healthy subjects (M/F, 12/8; age, 23–51 years) were enrolled to measure both fast and postprandial myoelectrical activities for each 30-min recording. Our results indicated that meal ingestion significantly increased dominant frequency (3.15 ± 0.20 vs 3.23 ± 0.23 cpm; P < 0.05) and power (26.1 ± 3.8 vs 28.4 ± 3.9 dB; P < 0.05). The power ratio of the meal effect was 2.02 ± 2.07. Other parameters, including instability coefficient and percent of normal frequency, remained similar despite food ingestion. This newly designed EGG system is acceptable for clinically measuring gastric myoelectrical activity; the real-time display of many EGG parameters is an advantage with this new system. Received: May 1, 2000 / Accepted: July 28, 2000     

Effect of hypo- and hyperthyroidism on gastric myoelectrical activity

Although hypo- and hyperthyroid patients have different symptoms in the gastrointestinal tract, the mechanism of thyroid action on the gut remains poorly understood. Thus the aim of this study was to investigate the effect of hypo- and hyperthyroidism on gastric myoelectrical activity, gastric emptying, dyspeptic symptoms. Twenty-two hyperthyroid (median age 45, 15 females) and 11 hypothyroid (median age 42, 10 females) patients were included into the study. Dyspepsia score, hypo- and hyperthyroid symptom scale, abdominal ultrasonography and upper gastrointestinal endoscopy were performed. Gastric myoelectrical activity was measured by electrogastrograpy (EGG) before and after therapy both preprandially and postprandially and compared with age, gender, and body-matched controls (12 for hypothyroid, 15 for hyperthyroid patients). Radionuclide gastric emptying studies were performed with a solid meal. Hypothyroid patients revealed a significant increase in preprandial tachygastria as compared with controls (12.3% vs 4.8%). The percentage of preprandial normal slow waves (2.4–3.7 cpm) was below 70% (dysmotility) in 7 of 11 hypothyroid patients versus 2 of 12 controls (P < 0.05). Hyperthyroid patients revealed a significantly higher preprandial (3.1 vs 2.8) and postprandial (3.4 vs 3) DF when compared with the controls (P < 0.05). A higher percentage of postprandial taschygastria (7.9 vs 0) was present in hyperthyroid patients than in the controls (P < 0.05). The decrease on postprandial EGG power (power ratio < 1) was observed in 7 patients the in hyperthyroid group and 1 in controls (P < 0.05). The percentage of postprandial normal slow waves was below 70% in 10 of 20 hyperthyroid patients vs 1 of 15 controls (P < 0.05). After therapy these differences disappeared in the euthyroid state. The hypo- and hyperthyroid symptom scale correlated to dyspepsia score. Dyspepsia score in hyperthyroidism correlated to power ratios in hyperthyroid patients. We detected some correlations between serum levels of fT3 or fT4 and some EGG parameters in hypo- and hyperthyroidism. Dyspepsia score and hypo- and hyperthyroid symptom scale were improved significantly after therapy in the euthyroid state. In conclusions, we showed gastric dysrhythmia by EGG in both hypo- and hyperthyroid patients. Dyspeptic symptoms correlated to the activity of thyroid disease. After therapy, these findings and dyspeptic symptoms improved in the euthyroid state. Abnormalities of power ratios may be responsible of dyspeptic symptoms in hyperthyroid patients. EGG may be a useful and noninvasive tool for detecting gastric disturbances during hypo- and hyperthyroidism.     

Impaired gastric myoelectricity in patients with chronic pancreatitis： Role of maldigestion

AIM: To investigate whether gastric myoelectrical activity was impaired in patients with chronic pancreatitis (CP) and to explore the role of pancreatic enzyme in regulating gastric myoelectrical activity. METHODS: Twenty CP patients and 20 controls participated in the study. Gastric myoelectrical activity was recorded by a homemade electrogastrography (EGG) device. Two experiments were carried out. In experiment one, EGG was recorded in both controls and CP patients. While in experiment two, either pancreatic enzymes or placebo was given together with test meals. Spectral analysis was used to generate various EGG parameters. RESULTS: The control subjects, but not the CP patients, showed typically increased postprandial dominant frequency. The postprandial dominant power (DP) increment (2.24±1.13 vs 5.35±0.96 dB, P= 0.04) and the percentage of normal 2-4 cpm slow waves (63.0±3.8% vs 77.4±3.1%, P<0.05) were lower in CP patients when compared with the control. In the 20 CP patients, the DP increment (4.76±1.02 vs 2.53±1.20 dB, P<0.05) and the postprandial percentage of normal 2-4 cpm (74.4±2.8% vs 64.8±5.7%, P<0.05) were significantly higher with pancreatic enzyme replacement than the placebo. CONCLUSION: CP patients have an abnormal postprandial stomach myoelectricity showing poor response in dominant frequency/power and regularity, whereas these abnormalities are corrected after pancreatic enzyme replacement. Maldigestion is likely to be the factor leading to abnormal postprandial gastric myoelectricity of CP patients.     

Electrogastrographic characteristics in patients of stomach cancer

Using a homemade electrogastrography (EGG) system, we studied the characteristics of myoelectrical rhythm in gastric cancer (GC) patients. Based on a short-term Fourier transform, recorded slow waves could be automatically analyzed to obtain the following parameters: dominant frequency/power, percent of normal rhythm (2.4–3.7 cpm), power ratio, etc. Fifty histologically confirmed GC patients (34 men, 16 women) were enrolled before surgical intervention to measure their fasting and postprandial EGG parameters for 30 min. The cancerous parameters of GC patients were then obtained postoperatively. In addition, 46 healthy subjects were enrolled for comparison. When compared to controls, GC patients had the following characteristics: absence of postprandial increase in dominant frequency (GC: 3.04 ± 0.47 vs 3.07 ± 0.44 cpm, NS; controls: 3.02 ± 0.31 vs 3.21 ± 0.25 cpm, P < 0.001), marked power response after meal (P < 0.05), and obvious power ratio (4.58 ± 7.38 vs 2.27 ± 2.05, P < 0.05). Multivariate analysis indicated that advanced GC was the factor responsible for the obvious dominant power enhancement after meal (P < 0.05). Other demographic, clinical, and cancerous factors did not influence EGG parameters. We conclude that apparent arrhythmia is not encountered in GC patients, although they mainly exhibit obvious postprandial power response. Advanced GC is likely responsible for this power enhancement on EGG recording.     

Identification of Gastric Contractions from Cutaneous Electrogastrogram

Objective : The objective of this study was to investigate whether gastric contractions in the fasting and fed state can be identifled from the cutaneous electrogastro-gram. Methods : Simultaneous measurements of gastric myoelectrical and manometric activities were made in 10 healthy female volunteers from 1:00 AM to 9:45 AM. For manometric recording, a catheter incorporating solid state transducers was used. Cutaneous electro-gastrography (EGG) was used for myoelectrical recording. All EGG data from 1:00 AM to 7:30 AM that occurred during motor quiescence, all EGG data that occurred during antral contractions, and 2-h EGG data after breakfast given at 7:30 AM were quantitatively analyzed and compared with each other. The EGG in three specific periods (fasting without antral contractions, fasting with contractions, and postprandial) was characterized by four parameters that include frequency, power, and stabilities of the frequency and power. Results: 1 ) the peak power of the postprandial EGG was, respectively, 12.5 dB (about 2-fold increase n i amplitude) and 6.8 dB (ahout 1-fold increase in amplitude) higher than that during motor quiescence (p < 0.05) and motor activity in the fasting state; 2) the dominant frequency of the postprandial EGG was, respectively, 6% and 13% higher than that during motor quiescence and motor activity (p < 0.05) in the fasting state; 3) the peak power of the fasting EGG was 48% more unstable during motor activity than motor quiescence (p < 0.05); 4) the stability of the EGG frequency was not significantly different during the three different periods. Conclusion : The EGG provides important and useful information for the assessment of gastric motility. An unstable EGG peak power is indicative of gastric contractions in the fasting state. An increase in EGG peak power and/or dominant frequency after a solid test meal suggests a normal postprandial gastric motility.     

2型糖尿病胃动力障碍的临床研究

[目的]应用胃电图(EGG)研究2型糖尿病(DM)胃动力的变化.[方法]选取2型DM患者60例,正常对照30例,对两组EGG的主频(FP)、振幅(AP)、胃动过缓百分率(B%)的变化与血糖的关系进行研究.[结果]DM组与正常对照组的空腹和餐后FP无统计学意义.两组餐后AP均显著高于空腹(P＜0.05),但两组比较无统计学意义.两组餐前和餐后B%比较,DM组均明显高于正常对照组(P＜0.05).DM空腹血糖(FBG)与餐前、餐后B%呈正相关,随着FBG的升高,B%呈相关升高(P＜0.01).[结论]DM患者存在明显EGG异常,表现为胃动过缓明显增多的胃电节律紊乱.DM患者FBG与餐前、餐后B%呈正相关.     

Ambulatory electrogastrography in patients with sclerodermia, delayed gastric emptying, dyspepsia, and irritable bowel syndrome. Is there any clinical relevance?

Background: Changes in electrogastrographic parameters are described in patients with irritable bowel syndrome, sclerodermia, dyspepsia, and delayed gastric emptying in static measurements. However, no information is available about changes in ambulatory measurements. The objective of this study was to find parameters that discriminate between these diseases using cutaneous 24-h-electrogastrography. Methods: Cutaneous 24-h electrogastrography (EGG) measurements were taken from 20 patients with dyspepsia, 10 patients with systemic sclerosis (sclerodermia, SSc), 7 patients with irritable bowel syndrome (IBS), 7 patients with delayed gastric emptying, and 10 healthy volunteers. Measurements were made using a DIGITRAPPER EGG (Synectics Medical Inc., Stockholm, Sweden) and the accompanying computerized data analysis package (ElectroGastroGram Version 6.30, Gastrosoft Inc., Synectics Medical Inc., Stockholm, Sweden). Frequency and power were compared pre- and postprandially, as well as during the entire day of measurement. Results: The 24-h measurements in healthy volunteers revealed 45.00%+/-12.12% normal values (2.4-3.7 cpm), 30.10%+/-7.15% bradygastric values (<2.4 cpm), and 24.20%+/-7.76% tachygastric values (>3.7 cpm). There was no significant change in frequency between rest and motion, but there was a significant increase in power (P<0.05). There was significantly more bradygastria in patients with dyspepsia periprandially as well as after 24 h (P<0.01) than in healthy volunteers. The mean power of patients with dyspepsia was significantly higher than that of patients with IBS (P<0.05). Conclusion: Cutaneous 24-h-EGG may be used as an additional means of differentiating between dyspepsia and IBS.