Myoelectrical Activity In Patients Research Articles

Effect of liquid and solid test meals on symptoms and gastric myoelectrical activity in patients with gastroparesis and functional dyspepsia.

Patients with gastroparesis (GP) and functional dyspepsia (FD) have similar symptoms, but the pathophysiology of postprandial symptoms remains uncertain. To compare symptoms and gastric myoelectrical activity (GMA) after liquid and solid test meals in patients with GP and FD. Patients enrolled in the Gastroparesis Clinical Research Consortium Registry were studied. Clinical characteristics were measured with standard questionnaires. GP was determined by 4-h solid-phase gastric scintigraphy. GMA was measured using electrogastrography before and after ingestion of a water load or nutrient bar on separate days. Symptoms were measured on visual analog scales. GMA responses to the water load for individual patients were also determined. 284 patients with GP and 113 with FD were identified who ingested both test meals. Patients with GP and FD had similar maximal tolerated volumes of water [mean (SD) 378 (218) ml vs. 402 (226) ml, p=0.23] and reported similar intensity of fullness, nausea, bloating, and abdominal discomfort after the test meals. Twenty-six percent and 19% of the patients with GP and FD, respectively, ingested subthreshold (<238ml) volumes of water (p=0.15). Gastric dysrhythmias were recorded in 66% of the GP and 65% of the FD patients after the water load. Symptoms and GMA were similar in both groups after ingestion of the nutrient bar. The similarity in GMA responses and symptoms after ingestion of solid or liquid test meals suggests GP and FD are closely related gastric neuromuscular disorders.

Clinical features and gastric myoelectrical activity in patients with idiopathic and post‐surgical rapid gastric emptying who present with unexplained chronic nausea

The cause of chronic nausea can be difficult to diagnose. Idiopathic rapid gastric emptying (iRGE) can cause nausea, but limited literature exists on clinical and pathophysiological features. In contrast, dumping syndrome or post-surgical rapid gastric emptying (psRGE) is well-known and may present with early phase vasomotor symptoms, diarrhea, and late phase reactive hypoglycemia. Our aim is to compare clinical and gastric motility characteristics in patients with iRGE and psRGE and unexplained chronic nausea. A retrospective study was conducted on patients with unexplained chronic nausea and RGE (<30% retention of a standard isotope-labeled solid meal at 1-h). Gastric myoelectrical activity (GMA) was recorded during water load satiety tests (WLST) using validated electrogastrogram (EGG) recording methods. Thirty iRGE and sixteen psRGE patients with unexplained chronic nausea were identified; average 1-hour meal retention was 18.6% and 16.2%, respectively. Nausea, bloating, early satiety, and bowel function were similar in the two groups; fewer iRGE patients had abdominal pain and none had vasomotor symptoms. Normal 3cpm GMA was recorded in 44% of iRGE vs 29% of psRGE, tachygastria in 13% vs 43%, bradygastria in 25% vs 14%, and mixed in 19% vs 14% (p values >0.05). Abnormal WLST volume (<300ml) was found in 69% of iRGE and 43% of psRGE (p=0.36). (a) iRGE and psRGE patients may present with unexplained chronic nausea rather than classic vasomotor symptoms and diarrhea. (b) iRGE and psRGE patients had similar gastric dysrhythmias and accommodation dysfunction, which may contribute to RGE.

Obstructive Gastroparesis: Patient Selection and Effect of Laparoscopic Pyloroplasty

BackgroundFunctional obstructive gastroparesis is an understudied subtype of gastroparesis with normal 3 cycle per minute gastric myoelectrical activity that responds to botulinum toxin A injection and balloon dilation of the pylorus. AimsTo determine the effect of pyloroplasty on symptoms, weight, gastric emptying, and gastric myoelectrical activity in patients with gastroparesis and normal 3 cycle per minute gastric myoelectrical activity. MethodsTen patients (average age 36 years with gastroparesis and normal 3 cycle per minute gastric myoelectrical activity) who had at least two successful endoscopic pyloric therapies and then underwent pyloroplasty were identified. Electrogastrography with water load satiety test was performed to determine gastric myoelectrical activity. Gastric emptying was measured with 4-h scintigraphy. Key ResultsSix months after pyloroplasty, nine of ten patients reported improved symptoms and weight increased an average of 6.4 lb (p = 0.04). The average percentage of meal retained at 4 h decreased from 47% before to 16% after pyloroplasty (p < 0.01) and normalized in six patients. After pyloroplasty, the percent distribution of gastric myoelectrical activity power in the 3 cycle per minute range decreased at each measured interval compared with pre-pyloroplasty (p < 0.01). Conclusions(1) Pyloroplasty in these patients with obstructive gastroparesis improved gastric emptying and decreased 3 cycle per minute gastric myoelectrical activity, consistent with relief of functional gastric outlet obstruction. (2) Pyloric neuromuscular dysfunction is a key factor in delayed emptying in patients with functional obstructive gastroparesis.

A pilot study on disturbed gastric myoelectric activity in obstructed defecation syndrome

BackgroundElectrogastrography (EGG) is a noninvasive technique for recording gastric myoelectric activity. The aim of this study was to measure and record gastric myoelectric activity in patients with obstructed defecation syndrome (ODS) and to compare their results with those of normal individuals. MethodsForty-two patients (22 male) with ODS and a mean age of 41.02 y were enrolled in this prospective study after thorough clinical and physiologic assessment. Eleven normal subjects (six female) with a mean age of 39.2 ± 8.4 y were assigned to the control group. Both patients and controls were subjected to surface EGG in fasting and postprandial states. Data were recorded and analyzed via a computer system to reveal the EGG pattern in both groups. ResultsAbnormalities in the EGG were found in 24 (57.1%) of the 42 patients with ODS. EGG in ODS patients showed alterations in the fasting state in the form of a significant decrease of the normal gastric slow wave (P = 0.03) and a nonsignificant increase in gastric dysrhythmias. The EGG alterations of ODS patients were significantly improved in the postprandial state as the normal gastric slow waves significantly (P = 0.006) increased and the gastric bradycardia declined significantly (P = 0.02). No significant differences were observed in the power distribution between the ODS patients and the healthy controls. ConclusionsPatients with ODS showed an altered EGG pattern compared with that of healthy control subjects. The alterations in ODS patients were more clearly observed during the fasting state and improved significantly after eating.

Disorder of Gastric Myoelectric Activity in Patients with Cerebral Infarction:Electrogastrographic Assessment

In this study, gastric myoelectric activity in patients with acute cerebral infarction was investigated using electrogastrography. The patients were divided into four groups; those with mild brainstem infarction(group A, n=13, men:8, women:5, 75±2 years old), severe brainstem infarction(group B, n=6, men:4, women:2, 79±4 years old), mild non-brainstem infarction(group C, n=14, men:7, women:7, 76±3 years old), and severe non-brainstem infarction(group D, n=9, men:3, women:6, 87±2 years old). In group B, the% ratio of normogastria(2.4-3.6 cycles per minute)was significantly lower in the fasting period. The dominant power(DP)significantly increased after the meal in group C, but did not in group A, compared to before the meal. The DP increased in all patients in group C after the meal, whereas it increased in only five of ten patients in group A. The possibility of gastric dysfunction should be considered in patients with brainstem infarction.

Effect of kinesio taping in myoelectric activity in patients with shoulder impingement

Introduction: The complex shoulder joint is equipped with the greater joint mobility of the body, however, is commonly injured in repetitive, sport or occupational activities. Shoulder Impact Syndrome (SIS) is one of the most common injuries affecting the shoulder, thus causing limitations in its functionality. Several strategies have been used by physiotherapy for prevention and rehabilitation of SIS, one of them is the Kinesio Taping (KT). However, even with its abundant use there is still no clear evidence of its benefits. Objective: The aim of the study was to examine the effect of KT on myoelectric activity and the level of pain in patients with SIS. Method: Seven women with SIS participated, which performed the flexion and shoulder abduction up to 90° with and without KT. During the gestures, the pain level and surface electromyography data of the upper trapezoid, middle deltoid and anterior serratus were acquired. The treatment of the electromyography data was performed in the BIOMEC-SAS software and presented as percentage values of the maximum voluntary contraction. To compare the myoelectric activity and pain levels, it was performed, respectively, one way ANOVA and the Wilcoxon test (α &lt;0.05). Results: Pain reductions were observed and myoelectric activity of upper trapezius (46.0±34.4% MVIC to 35.6 ± 19.5% MVIC) and middle deltoid (39.0±11.5% MVIC to 35.2±12.5% MVIC) in motion abduction use of KT. No changes were observed in the signs during flexion movement. Conclusion: Finally, the KT generated a reduction in the level of pain and myoelectric activity of the middle deltoid and upper trapezius in the movement of abduction in patients with SIS.

A Retrospective Analysis of Clinical and Gastric Myoelectric Activity in Patients Receiving Gastric Electrical Stimulation for Refractory Gastroparesis

A Retrospective Analysis of Clinical and Gastric Myoelectric Activity in Patients Receiving Gastric Electrical Stimulation for Refractory Gastroparesis

Gastric myoelectrical activity in patients with inflammatory bowel disease.

Aim: Inflammatory bowel disease is characterized by the presence of gastrointestinal motility disturbances; however alterations in the gastric myoelectrical activity have not been characterized. In this study we have recorded the gastric myoelectrical activity in patients with ulcerative colitis (UC) and Crohn's disease (CD) during their clinical remission. Materials and Methods: Gastric activity was assessed using electrogastrography (EGG) in patients with UC (n = 60), CD (n = 40) and healthy controls (n = 40). In each case, their response to water load test, as well as the dominant frequency (DF), dominant power (DP) and the power ratio (PR) of the electrical activity were recorded. Results: In healthy controls, the resting DF was 2.57 ± 1.05 cycles per minute (cpm), which decreased after water ingestion (2.34 ± 0.99 cpm; P = 0.001). Compared to healthy controls, patients with UC had low resting DF (bradygastria) (2.57 ± 1.05 vs. 1.86 ± 1.28 cpm; P = 0.01). The change in DF after water ingestion was insignificant in patients with UC and CD. Post-water ingestion, healthy controls exhibited an increase in the DP as compared to the resting state, (7.1 [2.93, 102.56] vs. 15.94 [3.92, 133.41] µV2; P = 0.02). Patients with UC (1.26 [0.14, 9.83] vs. 3.27 [0.61, 42.12] µV2) and CD (2.54 [0.44, 47.06] vs. 15.8 [0.1, 126.68] µV2) also showed a significant increase in the DP post-water ingestion. Conclusions: Patients with ulcerative colitis have altered resting gastric myoelectrical activity during the remission phase of the disease.

Influence of percutaneous local therapy for hepatocellular carcinoma on gastric function

To investigate the influence of percutaneous local therapy on gastric myoelectrical activity in patients with hepatocellular carcinomas. Forty-four patients with hepatocellular carcinoma (HCC) [27 males and 17 females, ranging in age from 49 to 81 years old (69.7 ± 8.01 years)] who were admitted for percutaneous local therapy were enrolled in this study. We examined clinical abdominal symptoms using the Gastrointestinal Symptom Rating Scale (GSRS) before and 3 d after percutaneous local therapy. We also measured cutaneous fasting and postprandial electrogastrography (EGG) recordings before and 3 d after percutaneous local therapy. We found that the percentage of normogastria in the fasting period was lower in the Child B group than in the Child A group (66.8% ± 8.6% vs 84.0% ± 3.8%). After percutaneous local therapy for HCC, the percentages of normogastria in the fasting period were significantly decreased (81.6% ± 3.5% vs 75.2% ± 4.5%). None of the postprandial EGG parameters changed significantly after percutaneous local therapy for HCC. Percutaneous local therapy for HCC reduced the power ratio (PR). In particular, the PR of tachygastria was significantly decreased after therapy (P < 0.01). However, no significant differences were found in the postprandial EGG parameters. Likewise, no significant differences were found in the calculated GSRS scores obtained from the questionnaire before and after therapy. Gastric slow-wave dysrhythmias were induced by percutaneous local therapy in HCC patients, even though the GSRS scores obtained from the questionnaire did not change significantly.

Shoulder and forearm oxygenation and myoelectric activity in patients with work-related muscle pain and healthy subjects

We tested hypotheses of (a) reduced oxygen usage, oxygen recovery, blood flow and oxygen consumption; and (b) increased muscle activity for patients diagnosed with work-related muscle pain (WRMP) in comparison to healthy controls. Oxygenation was measured with near infrared spectroscopy (NIRS), and muscle activity with EMG for the extensor carpi radialis (ECR) and trapezius descendens (TD) muscles. Eighteen patients with diffuse neck-shoulder-arm pain and 17 controls (matched in age and sex) were equipped with NIRS and EMG probes. After determining an individual's maximum voluntary contraction (MVC) force, short-term (20 s) isometric contractions for the ECR and TD of 10, 30, 50 and 70 % MVC generated ∆StO₂ and StO₂% recovery (Rslope) from NIRS, and RMS%max from EMG signals. In addition, upper arm venous (VO) and arterial (AO) occlusions generated slopes of total hemoglobin (HbTslope) and deoxyhemoglobin (HHbslope) for the resting ECR as surrogates of blood flow and oxygen consumption, respectively. Mixed model analyses, t tests, and Mann-Whitney test were used to assess differences between groups. There was no significant difference in MVC between groups for either muscle. Also, ∆StO₂%, Rslope for either muscle, and ECR-HbTslope were not different between groups, thus our hypotheses of reduced oxygen use, recovery, and blood flow for patients were not confirmed. However, patients had a significantly lower ECR-HHbslope confirming our hypothesis of reduced consumption. Further, there was no difference in RMS%max during contractions meaning that the hypothesis of increased activity for patients was not confirmed. When taking into account the number of NIRS variables studied, differences we found between our patient group and healthy controls (i.e., in forearm oxygen consumption and shoulder oxygen saturation level) may be considered modest. Overall our findings may have been impacted by the fact that our patients and controls were similar in muscle strength, which is in contrast to previous studies.

Gastric myoelectrical activity in patients with primary biliary cirrhosis

To examine gastric myoelectrical activity in patients with primary biliary cirrhosis (PBC). The study comprised 11 female PBC patients (average age 53.4 years, range 43-70) and two aged-matched control groups: 11 (53.4 years, range 37-78) healthy women, and 10 female patients with chronic hepatitis C, CHC (53.9 years, range 35-66), who were examined prior to administration of an antiviral therapy. Every subject underwent an electrogastrographic recording comprising a 30-min interdigestive and a 120-min postprandial period. Abnormal electrogastrograms, containing prolonged epochs of tachygastria in the postprandial phase were found in 2 out of 11 (18.2%) patients having both stage IV of the Scheuer's PBC classification, as well as in 1 patient out of 10 (10%) with CHC at stage F2 according to the METAVIR fibrosis score. Electrogastrographic abnormalities do not seem to be pathognomonic for the PBC as a disease, but rather would be considered an unspecific sequel of a morbid liver affection.

Twenty-four-hour gastric myoelectrical activity in patients with Parkinson disease: Use of ambulatory cutaneous electrogastrograms

Twenty-four-hour gastric myoelectrical activity in patients with Parkinson disease: Use of ambulatory cutaneous electrogastrograms

7 Characteristics of the electrogastrogram in patients with cyclic vomiting syndrome

Cyclic vomiting syndrome (CVS) is an unexplained disorder characterized by recurrent attacks of nausea and vomiting. The aim of this study was to investigate the characteristics of gastric myoelectrical activity in patients meeting Rome II criteria for CVS and studied between cycles using cutaneous electrogastrography (EGG).Methods: 11 patients (6M, 5F, mean age: 31 years, range: 16–60) with CVS (5 symptomatic and 6 asymptomatic at the time of the study) underwent EGG between acute CVS attacks. EGG recordings were made for 30 minutes in the fasting state and for 60 minutes after ingestion of a caloric liquid meal (Boost, 360 kcal). Power spectral analysis methods were used to extract quantitative EGG parameters: EGG dominant frequency/power, change in postprandial EGG power, percentages of normal slow waves (2 to 4 cpm) and dysrythmias including tachygastria (slow‐wave frequency &gt;4 cpm) and bradygastria (slow‐wave frequency &lt;2 cpm) in each recording session. Patients were asked to score their symptoms of nausea, vomiting and abdominal pain (0 = none, 4 = constant) during both pre‐ and postprandial periods. Data are expressed as mean ± SE.Results: 7/11 demonstrated an abnormal EGG (dysrhythmia &gt;30% in 4 patients and a decrease in postprandial EGG power in 6 patients). 5/11 patients had symptoms (nausea) during EGG recording and all had an abnormal EGG. The major abnormalities of EGG were tachygastria and a decrease in EGG postprandial power change. In comparison with asymptomatic patients at the time of the study, symptomatic patients had significantly more tachgastria (20.4 ± 3.9% vs. 6.7 ± 2.7%, P = 0.01) and significantly less normal slow waves (67.6 ± 2.0% vs. 86.7 ± 2.8%, P &lt; 0.05) in the fed state. The increase in EGG postptandial power in symptomatic patients was also significantly less than asymptomatic patients (­2.55 ± 1.01 dB vs. 1.14 ± 0.54 dB, P &lt; 0.05).Conclusions: 1) Abnormalities of EGG are presented in CVS between acute episodes and could explain some of the symptoms present; 2) Abnormal gastric myoelectrical activity is part of the spectrum of the CVS patients.

Psychosocial distress is associated with abnormal gastric myoelectrical activity in patients with functional dyspepsia

Objective. Functional dyspepsia (FD) is a heterogeneous and loosely defined clinical syndrome that is characterized by persistent or recurrent abdominal pain or discomfort centered in the upper abdomen without any identifiable structural or biochemical basis. Gastric myoelectrical activity in functional dyspepsia patients with gastric reddish streaks as a subgroup has not previously been investigated and the potential role of psychosocial distress in the genesis of gastric dysrhythmia in patients with FD is unclear. Material and methods. Electrogastrography was performed in 45 patients with FD and 35 healthy controls for 30 min in the fasting state and 30 min postprandially. Psychological distress and the number and severity of stressful life events were measured using self-rating questionnaires. Results. FD patients had a higher percentage of pre- and postprandial dysrhythmia, lower dominant frequency, and a higher instability coefficient as compared to healthy controls. In FD patients, severity of stressful life events was positively correlated with the percentage of tachygastria in the fasting state (r=0.43, p=0.005) and marginally positively correlated with the percentage of postprandial tachygastria (r=0.253, p=0.098) and instability coefficient of the dominant frequency (r=0.256, p=0.093). Total number of stressful life events was marginally positively correlated with fasting tachygastria (r=0.25, p=0.098) and instability coefficient of the postprandial dominant frequency (r=0.287, p=0.056). Interpersonal sensitivity was found to be negatively correlated with fasting dominant frequency in FD patients (r= − 0.311, p<0.05). Conclusions. FD patients with gastric reddish streaks have abnormal fasting and postprandial gastric myoelectrical activity. Perceived severity of stressful life events and interpersonal sensitivity are associated with disturbance of gastric myoelectrical activity.

Impaired circadian rhythm of gastric myoelectrical activity in patients with multiple system atrophy

In order to evaluate gastric motility and its circadian rhythm in patients with multiple system atrophy (MSA) and healthy control subjects, we measured gastric myoelectrical activity (GMA) for 24 hours using a cutaneous electrogastrogram (EGG) recorder in 14 MSA patients and 9 age-matched controls. We analyzed six 10-minute segments of EGG before and after each meal and two 20-minute EGG segments during sleep; three parameters were used for the analysis: dominant frequency (DF), instability coefficient of dominant frequency (ICDF), and dominant power (DP). DF increased during daytime and decreased during sleep in the control, while this circadian variation was blunted in the patients with MSA. The average DF of the eight segments in the MSA patients did not differ from that of the control. Both MSA patients and control subjects did not show the circadian variation of ICDF and DP. The average ICDF of the eight segments in the patients with MSA was significantly decreased when compared with that of the control (p < 0.01). No differences were observed in DP between the two groups. This study indicates that the healthy subjects appear to have a circadian rhythm of DF, and the patients with MSA appear to have impaired circadian rhythm of DF and decreased ICDF possibly due to the degeneration of the central autonomic neurons.

Effect of single-dose administration of recombinant interferon-alpha2b on gastric myoelectrical activity in patients with chronic hepatitis C

Upper abdominal complaints during interferon therapy may result from impaired gastric motility and/or evacuatory function. We examined the effect of acute administration of interferon on gastric myoelectrical activity (GMA) with the use of surface electrogastrography. The study population comprised 25 patients with chronic hepatitis C. All of them were naive to interferon. On 2 days, after a 25-min basal GMA registration, in group A (5 men, 7 women, aged 44.3 +/- 2.8 years) placebo or 5 million i.u. recombinant interferon alpha-2b (IFNA) was administered s.c. and the GMA was recorded in the interdigestive state for two periods (2 h and 4 h), separated by a 15-min break. In group B (7 men, 6 women, aged 44.7 +/- 3.9 years) placebo or 5 million i.u. IFNA was injected s.c. after the ingestion of a semiliquid test meal of 364 kcal. Subsequently, the postprandial GMA was recorded for two periods (2 h and 4 h), separated by a 15-min break. A typical flu-like syndrome was observed in 91.7% of patients in group A, and in 92.3% of patients in group B, thus providing evidence of the pharmacodynamic efficiency of the IFNA administration. In the fasted state, IFNA brought about a negligible increase in the rhythmicity and power of the gastric slow waves. IFNA did not elicit any statistically significant effect on gastric slow-wave activity postprandially. Acute administration of interferon does not involve any deterioration of GMA that could be linked to the previously reported upper abdominal symptoms in patients undergoing treatment with this drug.

Impaired gastric myoelectrical activity in patients with Parkinson's disease and effect of levodopa treatment.

The aim of this study was to evaluate gastric myoelectrical activity in patients with Parkinson's disease during and after levodopa treatment. Thirteen Parkinson's patients and 13 age-matched Parkinson's-free controls were enrolled. Electrogastrography was used to record gastric myoelectrical activity in all subjects for 30 min before and 30 min after a standard meal. In the group with Parkinson's disease, gastric myoelectrical activity was recorded during both the "on" (with levodopa treatment) and the "wearing-off" (without levodopa for at least 12 hr) periods. Results were as follows. (1) The patients without treatment showed a significantly lower percentage of regular slow waves and a significantly higher instability coefficient of the dominant frequency; (2) the patients showed an absence of the normal postprandial increase in gastric slow wave frequency which was seen in the controls: and (3) treatment with levodopa resulted in an improvement in the fed state, including a marginal increase in the percentage of regular slow waves (P = 0.1), a significant decrease in the instability coefficient, and an enhanced postprandial power increase. In conclusion, patients with Parkinson's disease have reduced slow wave rhythmicity and an impaired postprandial response in gastric myoelectrical activity. These abnormalities may be partially corrected with levodopa treatment in the fed state.

Gastric myoelectrical activity in patients with recurrent gastric or duodenal ulcers.

The aim of this study was to characterize gastric myoelectrical activity in patients with recurrent gastric ulcer (GU) or duodenal ulcer (DU), and to compare gastric motility between these two groups of patients. Studies were performed in 59 patients with recurrent active peptic-ulcer disease as diagnosed by gastrointestinal endoscopy: 31 patients had a GU and 28 patients had a DU. Gastric myoelectrical activity was evaluated by cutaneous electro-gastrography (EGG). The following EGG parameters were assessed: the percentage of normogastria (regular 2.4-3.6 cpm slow waves); the EGG power ratio; and the occurrence of a postprandial dip (PD), which is the transient decrease in EGG frequency after a meal. In the GU group, no significant change occurred in the percentage of normogastria or in the EGG power ratio observed after treatment with a proton-pump inhibitor. During the healed stage, the occurrence of PD remained unchanged. In contrast, in the DU group, the percentage of normogastria and the EGG power ratio were significantly increased after treatment. Moreover, during the healed stage, the occurrence of PD significantly increased compared with that during the active stage. These findings suggest that abnormal gastric myoelectrical activity plays an important role in the pathophysiology of recurrent GU rather than DU.

Effect of peritoneal dialysis on gastric myoelectrical activity in patients with chronic renal failure.

Impaired gastric myoelectrical activity has been reported in patients with chronic renal failure (CRF). The effect of peritoneal dialysis on this function has not previously been described. The aim here was to investigate the effect of peritoneal dialysis on gastric myoelectrical activity. Gastric myoelectrical activity was recorded by electrogastrography (EGG) in 23 patients with CRF (18 with dyspepsia) during peritoneal dialysis and with the peritoneal cavity empty of dialysis fluid (14 patients), and in 20 healthy controls. Two 30-min EGG recordings before and after a solid test meal were analyzed using spectral analysis methods. No significant difference in the percentage of normal 2- to 4-cpm slow waves was found in patients on peritoneal dialysis compared to those with the peritoneal cavity empty of dialysis fluid or to controls (in fasting state 83 +/- 3%, 80 +/- 5% and 89 +/- 4%, in fed state 91 +/- 3%, 86 +/- 4% and 83 +/- 4%, respectively). It was found that the power ratio (change in power of normal slow waves in fed state) was significantly higher in the 14 patients on peritoneal dialysis compared to the same patients with the peritoneal cavity empty of dialysis fluid (27.2 +/- 10.7 vs 8.6 +/- 4.8, P < 0.05). There was no significant difference in the power ratio between patients with the peritoneal cavity empty of dialysis fluid and controls (8.6 +/- 4.8 vs 7.5 +/- 2.2). The subgroup of patients with no dyspepsia had a significantly higher power ratio compared to those with dyspepsia both on dialysis and with the peritoneal cavity empty of dialysis fluid (39.4 +/- 13.7 vs 12.4 +/- 5.2 and 29.2 +/- 21.5 vs 2.8 +/- 0.4 respectively, P < 0.05). In conclusion, there was no significant difference in gastric myoelectrical activity between patients with the peritoneal cavity empty of dialysis fluid and controls. Dialysis fluid in the peritoneal cavity seems to enforce the gastric myoelectrical signal.

Effect of dialysis modalities on gastric myoelectrical activity in end-stage renal disease patients

Gastric motility is controlled by gastric myoelectrical activity, which propagates from the proximal body to the distal antrum at a frequency of 3 cycles/min. In uremic patients, dyspeptic symptoms are common. To investigate whether dialysis modality affects gastric myoelectrical activity in uremic patients, we performed electrogastrography (EGG) in 41 patients without diabetes with end-stage renal disease (ESRD) undergoing hemodialysis (HD; n = 22) and continuous ambulatory peritoneal dialysis (CAPD; n = 19). EGG was performed noninvasively using abdominal surface electrodes in the fasting state before and 4 hours after HD and at empty and 2 hours after CAPD with 2,000 mL of dialysate. There were no significant differences in age, sex, body weight, duration of dialysis, and percentage of patients with upper gastrointestinal (UGI) symptoms (63.6% versus 42.1%). CAPD patients had significantly lower serum albumin levels (3.4 ± 0.4 versus 3.9 ± 0.4 g/dL; P < 0.05), greater serum total-cholesterol levels (189 ± 33 versus 157 ± 36 mg/dL; P < 0.05), and greater percentages of patient with early satiety (42.1% versus 13.6%; P < 0.05) than HD patients. Dominant power significantly increased after HD (251.3 ± 157.5 versus 512.9 ± 390.0 dB; P < 0.05) but seemed to decrease after CAPD without statistical significance (416.2 ± 323.6 versus 283.8 ± 280.7 dB). There was no difference in the normal slow-wave frequency (NSWF) between HD and CAPD patients (predialysis, 60.7% ± 29.3% versus 52.2% ± 36.7%; postdialysis, 56.3% ± 32.0% versus 50.9% ± 34.2%). Tachygastria significantly increased after CAPD (pre-CAPD, 2.35% ± 4.3% versus post-CAPD, 10.0% ± 14.8%; P < 0.05). There was a significant correlation between changes in tachygastria after CAPD and grade of early satiety in CAPD patients with UGI symptoms (r = 0.74; P < 0.05). Changes in NSWF after CAPD significantly correlated with age (r = –0.51; P < 0.05). In conclusion, dialysis modalities seem to have different effects on gastric myoelectrical activity in patients with ESRD.