Obesity and Gastroesophageal Reflux: Quantifying the Association Between Body Mass Index, Esophageal Acid Exposure, and Lower Esophageal Sphincter Status in a Large Series of Patients with Reflux Symptoms

Introduction  Obesity and gastroesophageal reflux disease (GERD) are increasingly important health problems. Previous studies of the relationship between obesity and GERD focus on indirect manifestations of GERD. Little is known about the association between obesity and objectively measured esophageal acid exposure. The aim of this study is to quantify the relationship between body mass index (BMI) and 24-h esophageal pH measurements and the status of the lower esophageal sphincter (LES) in patients with reflux symptoms. Methods  Data of 1,659 patients (50% male, mean age 51 ± 14) referred for assessment of GERD symptoms between 1998 and 2008 were analyzed. These subjects underwent 24-h pH monitoring off medication and esophageal manometry. The relationship of BMI to 24-h esophageal pH measurements and LES status was studied using linear regression and multiple regression analysis. The difference of each acid exposure component was also assessed among four BMI subgroups (underweight, normal weight, overweight, and obese) using analysis of variance and covariance. Results  Increasing BMI was positively correlated with increasing esophageal acid exposure (adjusted R ² = 0.13 for the composite pH score). The prevalence of a defective LES was higher in patients with higher BMI (p < 0.0001). Compared to patients with normal weight, obese patients are more than twice as likely to have a mechanically defective LES [OR = 2.12(1.63–2.75)]. Conclusion  An increase in body mass index is associated with an increase in esophageal acid exposure, whether BMI was examined as a continuous or as a categorical variable; 13% of the variation in esophageal acid exposure may be attributable to variation in BMI. An erratum to this article can be found at     

Ambulatory pH: monitoring with a wireless system

Background Currently, pH monitoring is the gold standard for assessing esophageal acid exposure in patients with gastroesophageal reflux disease (GERD). The shortcomings of 24-h pH-monitoring wires led to the development of a 48-h, catheter-free pH measurement system using the telemetry technique with the BRAVO capsule. This prospective study aimed to compare conventional 24-h pH monitoring with the BRAVO catheter-free pH-monitoring system in patients with GERD, patients after antireflux surgery, and a healthy control group. Methods A sample of 133 participants were enrolled in the current trial and divided into three subgroups. Group 1 consisted of 10 healthy volunteers. Group 2 consisted of 123 patients with symptomatic gastroesophageal reflux and endoscopic signs of esophagitis. Group 3 consisted of 43 GERD patients (extracted from group 2) who underwent a laparoscopic 360° “floppy” Nissen fundoplication. All the patients underwent both conventional 24-h pH monitoring and BRAVO catheter-free pH monitoring. The data for both methods were recorded and compared in line with the different patient groups regarding their validity and reliability. Additionally, all the patients were interviewed with a standardized questionnaire concerning their subjective perception of the two different methods. Results Both the 24-h pH monitoring and the 48-h BRAVO catheter-free pH monitoring could be successfully performed for all the patients. During measurement, 122 of the patients (92%) continued working or performing daily activities. A significant difference could not be found regarding objective outcome between the two measurement methods in the three patient groups. The two methods showed comparable results in terms of data and measurement reliability. The validity also was comparable, with no significant differences within the groups. Concerning the patients’ subjective estimation of the two methods, the patients reported reduced regular activities and a higher level of discomfort during measurement with the conventional 24-h pH-monitoring system (p < 0.001 and p< 0.0001, respectively). Conclusion Both conventional 24-h pH monitoring and the 48-h catheter-free pH monitoring are valid and reliable recording devices for measuring esophageal acid exposure. However, from the patients’ point of view, the BRAVO capsule affords less discomfort in the throat and allows more normal daily activities.     

48-Hour pH Monitoring Increases the Risk of False Positive Studies When the Capsule is Prematurely Passed

Ambulatory wireless 48-h esophageal pH monitoring (Bravo Medtronic, Shoreview, MN, USA) has been shown to be more sensitive in detecting abnormal esophageal acid exposure compared with transnasal 24-h pH probes. However, accurate interpretation of the wireless monitoring data is paramount when contemplating surgical intervention for those with gastroesophageal reflux disease. The aim of this study is to evaluate the incidence of false-positive interpretations of this wireless monitoring data secondary to premature transit of the Bravo capsule into the stomach and subsequently into the duodenum prior to the completion of the 48-h study period. We reviewed 100 consecutive Bravo pH studies at our University Esophageal Motility Center. There were 58 women and 42 men included in our evaluation. Premature transit of the Bravo capsule into the stomach and subsequently into the small bowel was defined by a prolonged gastric pH phase with either evidence of alkalinization and no further reflux episodes or loss of communication with the Bravo capsule prior to the end of the 48-h data collection period. Of the 100 patients reviewed, 11% manifested evidence of early passage of the Bravo capsule resulting in a misinterpretation of the data as abnormal acid exposure. The mean time of inaccurate data after transit of the Bravo capsule was 18 h and 42 min. The mean length of time that the capsule was retained in the stomach prior to duodenal passage was 4 h. If the aforementioned data were included in the final interpretation of the study, it yielded a mean DeMeester score of 44.25 with a mean total time of pH <4 of 14.7% per case. Exclusion of the prolonged gastric phase from the final interpretation of each case resulted in a statistically significant reduction in the mean total time the pH <4 (4.33 vs. 14.7%, p < 0.05) and the mean DeMeester score (12.81 vs. 44.25 p < 0.05). The mean time from the initiation of esophageal pH data to the passage of the Bravo capsule into the stomach was 15 h and 22 min. The observation mandates meticulous inspection of the pH tracing by the interpreting physician throughout the entirety of a 48-h study to identify premature transit of the capsule. Tracings that show prolonged acid exposure or loss of communication with the Bravo capsule should be screened for the capsule’s possible early dislodgement and premature advancement into the stomach.     

Outcome after laparoscopic fundoplication is not dependent on a structurally defective lower esophageal sphincter

With the advent of laparoscopic surgery and the recognition that gastroesophageal reflux disease often requires lifelong medication, patients with normal resting sphincter characteristics are now being considered for surgery. The outcome of these patients after fundoplication is unknown and formed the basis of this study. The study population consisted of 123 patients undergoing laparoscopic Nissen fundoplication between 1992 and 1996. All patients had increased esophageal acid exposure on 24-hour esophageal pH monitoring. Patients were divided into those with a normal (n = 36) and those with a structurally defective (n = 87) lower esophageal sphincter (LES), based on LES resting pressure (normal >6 mm Hg), overall length (normal >2 cm), and abdominal length (normal > 1 cm), and their outcomes were assessed. Each group was subsequently divided into patients presenting with a primary symptom that was "typical" (heartburn, regurgitation, or dysphagia) or "atypical" (gastric, respiratory, or chest pain) of gastroesophageal reflux, and outcome was assessed. Median duration of follow-up was 18 months after surgery. Overall, laparoscopic fundoplication was successful in relieving symptoms of gastroesophageal reflux in 90% of patients. Patients with a typical primary symptom had an excellent outcome irrespective of the resting status of the LES (95% and 97%, respectively). Atypical primary symptoms were significantly more common in patients with a normal LES (29%) than in those with a structurally defective LES (10%; P <0.05), and these symptoms were less likely (50%) to be relieved by antireflux surgery. Laparoscopic antireflux surgery is highly successful and not dependent on the status of the resting LES in patients with increased esophageal acid exposure and primary symptoms "typical" of gastroesophageal reflux. Antireflux surgery should be applied cautiously in patients with atypical primary symptoms. Presented in part at the Thirty-Eighth Annual Meeting of The Society for Surgery of the Alimentary Tract, Washington, D.C., May 11–14,1997.     

Role of the lower esophageal sphincter and hiatal hernia in the pathogenesis of gastroesophageal reflux disease

The relative importance of the lower esophageal sphincter (LES) and hiatal hernia in the pathogenesis of gastroesophageal reflux disease is controversial. To identify the role of hiatal hernia and LES in reflux disease, 375 consecutive patients with foregut symptoms and no previous foregut surgery were evaluated. All patients underwent upper endoscopy, stationary manometry, and 24-hour esophageal pH monitoring. Hiatal hernia was diagnosed endoscopically, when the distance between the crural impression and the gastroesophageal junction was ≥2 cm. The LES was considered structurally defective when the resting pressure was ≤6 mm Hg, the overall length was less than 2 cm, and/or the abdominal length was less than 1 cm. Factors predicting abnormal esophageal acid exposure (composite score >14.7) were analyzed using multivariate analysis. The presence of a hiatal hernia and a defective LES were identified as independent predictors of abnormal esophageal acid exposure. LES pressure and abdominal length were reduced in patients with hiatal hernia by 4 mm Hg and 0.4 cm, irrespective of the presence of gastroesophageal reflux disease. It is concluded that both a structurally defective LES and hiatal hernia are important factors in the pathogenesis of reflux disease. It is hypothesized that in the presence of a structurally normal LES, the altered geometry of the cardia imposed by a hiatal hernia facilitates the ability of gastric wall tension to pull open the sphincter. Presented at the Thirty-Ninth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, La., May 17–20, 1998 (poster presentation).     

Esophageal pH Profile Following Laparoscopic Total Fundoplication Compared to Anterior Fundoplication

In Barrett’s esophagus, total abolition of reflux may give maximum protection against the development of malignancy. To determine whether laparoscopic anterior fundoplication gives the same degree of antireflux control as a total fundoplication, we analyzed a prospectively followed cohort of patients from randomized controlled trials of laparoscopic antireflux surgery. There were 167 patients who returned for routine esophageal pH studies within 6 months of surgery (123 laparoscopic total fundoplications and 44 anterior fundoplications). There was no difference in percentage time pH <4 between fundoplication groups, but the total number of reflux episodes was significantly different (total fundoplication, four reflux events vs. partial fundoplication, six reflux events; p = 0.03). It is difficult to believe that this difference is either biologically or clinically important. In patients with a second esophageal pH study more than 5 years later, both the percentage time pH <4 (0.1% total fundoplication vs. 2.7% partial fundoplication; p = 0.004) and total number of reflux episodes (three total fundoplication vs. 24 partial fundoplication; p = 0.002) were significantly different. However, the postoperative esophageal acid exposure was within the normal range for both total and partial fundoplication, so whether the statistical difference is clinically important, remains a moot point. Each author’s contribution to the article: 1. Conception & design, data acquisition, analysis and interpretation: ASYW, JCM, GGJ. 2. Drafting and critically revising the article: ASYW, JCM, GGJ. 3. Final approval of version to be published: ASYW, JCM, GGJ. This paper was presented at the 76th Annual Scientific Congress of the Royal Australasian College of Surgeons, May 10, 2007, Christchurch, New Zealand.     

Proton Pump Inhibitors Relieve and Prevent Symptoms Related to Gastric Acidity after Esophagectomy

Background Denervated stomach used as an esophageal substitute after esophagectomy often retains or spontaneously recovers acid production. The aims of the present study were to assess the relationship between esophageal acid exposure or gastric acidity and reflux-related symptoms after esophagectomy, and to assess the ability of proton pump inhibitors (PPIs) to relieve gastroesophageal reflux-related symptoms. Methods Forty-four patients underwent esophageal and gastric 24-h pH monitoring early after esophagectomy with gastric reconstruction. Initially, patients with both gastric acidity and reflux symptoms were treated with PPIs (Treatment group), then all patients with gastric acidity, whether symptomatic or not, were treated (Prevention group). Reflux-related symptoms were correlated with esophageal acid exposure and postoperative gastric acidity. Gastric acidity was then correlated with serum anti-Helicobacter pylori immunoglobulin G (IgG) titers and preoperative endoscopic findings Results Sixteen patients (36.4%) reporting reflux and showing gastric acid production were treated with PPIs, which provided relief to 13 (81.3%). Although symptoms did not correlate with the esophageal acid exposure, postoperative gastric acidity was significantly greater among patients who were symptomatic than among those who were not. Overall, acid production was lower in older patients (> 64 years of age), although older patients who were H. pylori-negative and without chronic atrophic gastritis also showed high levels of gastric acidity. Conclusions Proton pump inhibitors should be administered prophylactically early after esophagectomy to relieve and prevent reflux-related symptoms. Candidates for preventive therapy include those less than 64 years of age or older patients who are H. pylori-negative and without chronic atrophic gastritis.     

pH-metric analysis after successful antireflux surgery: Comparison of 24-hour pH profiles in patients undergoing floppy fundoplication or Roux-en-Y duodenal diversion

Fundoplication is the most widely used antireflux method, whereas Roux-en-Y duodenal diversion (partial gastrectomy, vagotomy, and Roux-en-Y reconstruction) has been used in fewer patients with more complicated gastroesophageal reflux disease. Abnormal esophageal pH values are normalized after successful fundoplication. However, very little is known about possible changes in the pH profile after successful Roux-en-Y duodenal diversion. A total of 37 patients with severe gastroesophageal reflux disease were treated by fundoplication (n=22) or Roux-en-Y duodenal diversion (n=15). Postoperatively all patients in both groups were symptom free and healing of esophagitis was verified endoscopically. After fundoplication, the 24-hour esophageal acid exposure decreased significantly (P=0.03) and the pH profile normalized (pH<4 in 5.8%±2.4% of the recorded time). However, the decrease in esophageal acid exposure was not significant (P=0.77) after successful Roux-en-Y reconstruction and the pH profile remained abnormal (pH<4 in 15.1%±4.3%). It was concluded that 24-hour esophageal pH monitoring is a reliable means of assessing the results of fundoplication, but the current test criteria should be reexamined in evaluating the results of Roux-en-Y duodenal diversion. Healing of esophagitis after Roux-en-Y duodenal diversion despite abnormal acid reflux, as shown by 24-hour pH measurements, suggests that duodenal contents also have a role in the pathogenesis of esophagitis in an acid milieu.     

Recurrent Heartburn after Laparoscopic Fundoplication is Not Always Recurrent Reflux

Introduction A small cohort of patients present after antireflux surgery complaining of recurrent heartburn. Many of these patients have been empirically recommenced on proton pump inhibitors. Objective The aim of this study was to determine whether patients with symptoms that suggest recurrent reflux had objective evidence of reflux, and to determine predictors of recurrent reflux. Methods We identified all patients from an existing database who had undergone pH monitoring for “recurrent heartburn” after fundoplication. These patients were then cross-referenced to another database, which recorded the outcomes for patients who had undergone a laparoscopic fundoplication. Patients complaining of dysphagia or other problems without heartburn were excluded from analysis. Results Seventy-six patients were identified who met the inclusion criteria. Fifty-six (74%) of these had a normal 24-h pH study. Thirty-five patients (63%) with a normal pH study were on medication for heartburn at the time of referral. Three factors were found to be associated with an abnormal 24-h pH study: a partial fundoplication (P = 0.039), onset of symptoms 6 months or more after surgery (P < 0.001), and a good symptom response when antireflux medication was recommenced (P = 0.015). Conclusions Not all patients complaining of recurrent heartburn after fundoplication have evidence of abnormal reflux. Objective evidence of abnormal esophageal acid exposure should be confirmed before recommencing antireflux medication. Presented at the 10th World Congress of the International Society for Diseases of the Esophagus (ISDE), Adelaide Convention Center, South Australia, Australia, February 24, 2006     

Duodeno-Gastric-Esophageal Reflux—What is Pathologic? Comparison of Patients with Barrett’s Esophagus and Age-Matched Volunteers

Introduction The aim of the study was to analyse pH- and bile-monitoring data in patients with Barrett’s esophagus and in age- and gender-matched controls. Subjects and Methods Twenty-four consecutive Barrett’s patients (8 females, 16 males, mean age 57 years), 21 patients with esophagitis (10 females, 11 males, mean age 58 years), and 19 healthy controls (8 females, 11 males, mean age 51 years), were included. Only patients underwent endoscopy with biopsy. All groups were investigated with manometry, gastric and esophageal 24-h pH, and simultaneous bile monitoring according to a standardized protocol. A bilirubin absorption >0.25 was determined as noxious bile reflux. The receiver operator characteristic (ROC) method was applied to determine the optimal cutoff value of pathologic bilirubin levels. Results Of Barrett’s patients, 79% had pathologic acidic gastric reflux (pH<4 >5% of total measuring time). However, 32% of healthy controls also had acid reflux (p < 0.05) without any symptoms. The median of esophageal bile reflux was 7.8% (lower quartile (LQ)–upper quartile (UQ) = 1.6–17.8%) in Barrett’s patients, in patients with esophagitis, 3.5% (LQ–UQ = 0.1–13.5), and in contrast to 0% (LQ–UQ = 0–1.0%) in controls, p = 0.001. ROC analysis showed the optimal dividing value for patients at more than 1% bile reflux over 24 h (75% sensitivity, 84% specificity). Conclusion An optimal threshold to differentiate between normal and pathological bile reflux into the esophagus is 1% (24-h bile monitoring with an absorbance >0.25).     

Transient Lower Esophageal Sphincter Relaxation in Morbid Obesity

Background  There is strong evidence that morbid obesity is often accompanied by gastroesophageal reflux. Gastroesophageal reflux is caused predominantly by transient lower esophageal sphincter relaxations (TLESRs). Only few data are available about TLESRs in patients with stage III obesity (body mass index > 35). The aim of this study was to analyze the frequency and types of TLESRs in patients with morbid obesity in different physiological stages (postprandial: upright and recumband) compared to patients with normal weight gastroesophageal reflux disease (GERD) and diffuse esophagus spasm (DES). Methods  In order to measure TLESRs in obese patients with and without GERD, three subgroups were prospectively performed: group I consisted of seven healthy controls, group II consisted of seven obese patients, group III consisted of seven non-obese patients with GERD, and in group IV, five patients were recruited with diffuse esophageal spasm. All participants underwent both conventional water-perfused stationary esophagus manometry and a 24-h ambulatory esophagus manometry, 24-h ambulatory pH monitoring, and esophago-gastroscopy. In order to measure the lower esophageal sphincter pressure (LESP) over a prolonged time under physiological conditions, a special solid-state sleeve catheter was used. Additionally, all patients were interviewed using a standardized questionnaire. Results  Compared to normal subjects, patients with morbid obesity and patients with gastroesophageal reflux show a substantial increase of TLESRs in the postprandial phase. There was a tendency towards more TLESRs per hour in patients with DES than in healthy subjects, but the difference was not statistically significant. The types of TLESRs differed with the LESP. The majority of isolated TLESRs were complete and incomplete. Some of the isolated TLESRs were accompanied by contractions of the tubular esophagus. Conclusion  Morbid obesity is associated with gastroesophageal reflux. The frequency of TLESRs has significantly increased compared to healthy subjects and does not differ statistically from patients with GERD. Isolated TLESRs are mostly incomplete in patients with a hypotonic LES.     

The impact of reflux composition on mucosal injury and esophageal function

The components of refluxed gastric juice are known to cause mucosal injury, but their effect on esophageal function is less appreciated. Our aim was to determine the effect of acid and/or bile on mucosal injury and esophageal function. From 1993–2004, 402 patients with reflux symptoms had 24-hour pH and Bilitec monitoring, manometry, and endoscopy with biopsies. Mucosal injury (esophagitis or Barrett’s esophagus) and esophageal function (lower esophageal sphincter [LES] characteristics and body contractility) in patients with acid reflux, bile reflux, or both were compared with patients without reflux. Reflux was present in 273/402 patients; of these, 37 (13.5%) had increased exposure to bile, 82 (30.0%) had increased exposure to acid, and 154 (56.4%) had increased exposure to both. Mucosal injury was most common with increased mixed acid and bile exposure, followed by acid alone, and was uncommon with bile alone (P<0.0001). Functional deterioration paralleled mucosal injury (P<0.0001). Mixed acid and bile exposure was present in more than half of patients with reflux and was associated with the most severe mucosal injury and the greatest deterioration of esophageal function. This suggests that composition of gastric juice is the primary determinant of inflammatory mucosal injury and subsequent loss of esophageal function. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–19, 2005 (oral presentation).     

The hypertensive lower esophageal sphincter: A motility disorder with manometric features of outflow obstruction

The aim of this study was to define the clinical presentation, motility characteristics, and prevalence and patterns of gastroesophageal reflux in patients with hypertensive lower esophageal sphincter (HTLES). HTLES was defined by a resting pressure measured at the respiratory inversion point on stationary manometry of greater than 26 mm Hg (ninety-.fth percentile of normal). One hundred consecutive patients (80 women, 20 men; mean age 54.7 years, range 23 to 89 years), diagnosed with HTLES at our institution between September 1996 and October 1999, were studied. Patients with achalasia or other named esophageal motility disorders or history of foregut surgery were excluded, but patients with both HTLESand ‘nutcracker esophagus’ were included. Themost commonsymptoms in patients withHTLES were regurgitation (75%), heartburn (71%), dysphagia (71%), and chest pain (49%). The most common primary presenting symptoms were heartburn and dysphagia. The intrabolus pressure, which is a manometric measure of Outflow obstruction, was significantly higher in patients with HTLES compared to normal volunteers. The residual pressure measured during LES relaxation induced by a water swallow was also significantly higher than in normal persons. There were no significant associations between any of the relaxation parameters studied (residual pressure, nadir pressure, duration of relaxation, time to residual pressure) and either the presence or severity of any symptoms or the presence of abnormal esophageal acid exposure. Seventy-three patients underwent 24-hour pH monitoring, and 26% had increased distal esophageal acid exposure. Compared to a cohort of patients with gastroesophageal reflux disease but no HTLES (n _ 300), the total and supine periods of distal esophageal acid exposure were significantly lower in the patients with HTLES and abnormal acid exposure. Patients with HTLES frequently present with moderately severe dysphagia and typical reflux symptoms. Approximately one quarter of them have abnormal esophageal acid exposure on pH monitoring. Patients with HTLES have significantly elevated intrabolus and residual relaxation pressures on liquid boluses, suggesting that Outflow obstruction is present.     

Altered Esophageal Motility and Gastroesophageal Barrier in Patients with Jejunal Interposition After Distal Esophageal Resection for Early Stage Adenocarcinoma

Introduction Limited resection of the esophagogastric junction has been proven to be safe and oncologically radical in patients with early esophageal cancer. Reconstruction with interposition of isoperistaltic jejunal loop (Merendino procedure) is supposed to prevent gastroesophageal reflux and therefore the recurrence of intestinal metaplasia at the anastomosis. The aim of this study was to assess the frequency of acid and nonacid refluxes after Merendino procedure using multichannel intraluminal impedance-pH (MII-pH) monitoring. Patients and Methods Between 2002 and 2005, 12 patients with esophageal adenocarcinoma underwent limited resection and jejunal interposition. Ten patients agreed to undergo a Gastrointestinal Symptom Rating Scale assessment, upper gastrointestinal (GI) endoscopy, esophageal manometry, and combined 24-h MII-pH monitoring more than 10 months postoperatively. Results Postoperatively, 4 (40%) patients reported belching without heartburn or acid regurgitation, 3 of them having a positive symptom index during 24-h MII-pH monitoring. Upper GI endoscopy revealed no inflammation, metaplasia, or stenosis at the esophagojejunal anastomosis. Esophageal manometry showed ineffective esophageal motility in four of ten patients. Combined 24-h MII-pH monitoring revealed normal distal esophageal acid exposure (% time pH < 4: 0.1% [0–1.5]), normal number of acid reflux episodes (3 [0–11]) but a high number of nonacid reflux episodes (82 [33–184]). Overall, eight patients revealed an abnormal number of nonacid reflux episodes. Conclusion The limited resection with jejunal interposition for early esophageal cancer is efficient in controlling acid but not nonacid reflux. While the clinical relevance of nonacid reflux in the recurrence of Barrett’s esophagus is currently unknown, endoscopic surveillance should be considered in these patients. Poster presented at the Digestive Disease Week, May 21, 2007, Washington DC.     

Esophageal mucosal damage may promote dysmotility and worsen esophageal acid exposure

This study determines the relationship among esophageal dysmotility, esophageal acid exposure, and esophageal mucosal injury in patients with gastroesophageal reflux disease (GERD). A total of 827 patients with GERD (confirmed by ambulatory pH monitoring) were divided into three groups based on the degree of mucosal injury: group A, no esophagitis, 493 patients; group B, esophagitis grades I to III, 273 patients; and group C, Barrett’s esophagus, 61 patients. As mucosal damage progressed from no esophagitis to Barrett’s esophagus, there was a significant decrease in lower esophageal sphincter pressure and amplitude of peristalsis in the distal esophagus, with a subsequent increase in the number of reflux episodes in 24 hours, the number of reflux episodes longer than 5 minutes, and the reflux score. These data suggest that in patients with GERD, worsening of esophageal mucosal injury may determine progressive deterioration of esophageal motor function with impairment of acid clearance and increase of esophageal acid exposure. These findings suggest that Barrett’s esophagus is an end-stage form of gastroesophageal reflux, and that if surgical therapy is performed early in the course of the disease, this cascade of events might be blocked. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (poster presentation).     

Prospective Assessment of Patient Selection for Antireflux Surgery by Combined Multichannel Intraluminal Impedance pH Monitoring

Introduction  Selecting gastroesophageal reflux disease (GERD) patients for surgery on the basis of standard 24-h pH monitoring may be challenging, particularly if this investigation does not correlate with clinical symptoms. Combined multichannel intraluminal impedance pH monitoring (MII-pH) is able to physically detect each episode of intraesophageal bolus movements, enabling identification of either acid or non-acid reflux episodes and thus establish the association of the reflux with symptoms. Materials and Methods  We prospectively assessed and reviewed data from 314 consecutive patients who underwent MII-pH for GERD not responsive or not compliant to proton pump inhibitor therapy. One hundred fifty-three patients with a minimum follow-up of 1 year constituted the study population. Clinical outcomes and satisfaction rate were collected in all patients who underwent laparoscopic Nissen–Rossetti fundoplication. Outcomes were reported for patients with normal and ineffective peristalsis and for patients with positive pH monitoring, negative pH monitoring and positive total number of reflux episodes at MII, and negative pH monitoring and normal number of reflux episodes at MII and a positive symptom index correlation with MII. Results  The overall patient satisfaction rate was 98.3%. No differences were recorded in the clinical outcomes of the patients with preoperative normal and ineffective peristalsis. No differences in patients’ satisfaction and clinical postoperative DeMeester symptom scoring system were noted between the groups as determined by MII-pH. Conclusion  MII-pH provides useful information for objective selection of patients to antireflux surgery. Nissen fundoplication provides excellent outcomes in patients with positive and negative pH and positive MII monitoring or Symptom Index association. More extensive studies are needed to definitively standardize the useful MII-pH parameters to select the patient to antireflux surgery.     

Computerized 24-hour ambulatory esophageal pH monitoring and esophagogastroduodenoscopy in the reflux patient. A comparative study.

Ambulatory 24-hour esophageal pH monitoring and esophagogastroduodenoscopy were performed in 72 patients with symptoms suggestive of gastroesophageal reflux. Additionally, 22 asymptomatic healthy volunteers underwent pH monitoring. In patients with classic reflux symptoms and endoscopic esophagitis, a mean of 5.41 minutes/hour of reflux below pH 4 was found compared to 0.70 minutes/hour in controls (p less than 0.0001). The mean number and duration of reflux events in this group were 1.51 events/hour and 4.0 minutes/event, compared with 0.31 events/hour and 2.26 minutes/event in volunteers (p less than 0.001, p less than 0.01). A new system for ambulatory esophageal pH monitoring is presented using a pH-sensitive radiotelemetry pill or a pH probe and computerized methods for ambulatory data collection, analysis, and storage. An overall sensitivity of 76% was obtained with a 91% selectivity for detection of acid reflux in 51 patients having classic symptoms of gastroesophageal reflux. Ambulatory pH monitoring was positive for acid reflux in seven of 11 patients with normal endoscopic findings. Conversely, eight of 12 patients with normal pH monitoring had endoscopic esophagitis. In 19 patients presenting with atypical symptoms or previous gastric surgery, endoscopic findings were normal in 15. Nine of these 15 were identified as acid refluxers by pH monitoring. A combined approach using both pH monitoring and endoscopy is warranted for maximal detection and quantification of disease. A clear clinical role for pH monitoring is seen in the early diagnosis of acid reflux, particularly in patients having normal endoscopic findings with nonspecific gastrointestinal complaints or previous gastric operations.     

Usefulness of combined gastric and esophageal pH monitoring in detecting gastroesophageal alkaline and mixed reflux

96 patients with 'typical' symptoms of gastroesophageal reflux were studied by means of combined gastric and esophageal pH monitoring. The aim was to assess the incidence of 'alkaline' and 'mixed' gastroesophageal reflux episodes as well as 'acid' reflux and their reciprocal relationship with esophagitis. 'Alkaline' gastroesophageal reflux was defined whenever the pH in the esophagus rose above 7, but only when there was a simultaneous or immediately previous rise of gastric pH to similar alkaline values resulting from duodenogastric reflux. 'Mixed' gastroesophageal reflux was defined whenever the pH in the esophagus dropped to 5.5-4.5, but only when there was a simultaneous or immediately previous rise of gastric pH above 4 related to duodenogastric reflux. Our data suggest that 'alkaline' gastroesophageal reflux is a rare phenomenon while 'mixed' gastroesophageal reflux episodes are present in 21% of these patients. 87% of patients with mixed reflux had esophagitis. Until analytical studies of refluxed material are available to clarify its composition, combined gastric and esophageal pH monitoring seems a useful test to correctly interpret the 'alkaline' and 'mixed' gastroesophageal reflux.     

The Effect of Roux-en-Y Gastric Bypass on Gastroesophageal Reflux Disease in Morbidly Obese Chinese Patients

Background  The prevalence of gastroesophageal reflux disease (GERD) is increasing in Eastern and Western countries. Obesity is recognized as a risk factor of gastroesophageal reflux disease. However, little information is available on the prevalence of gastroesophageal reflux disease in morbidly obese Chinese patients. The aim of this study was to compare the prevalence of GERD in Chinese patients with morbid obesity and age- and sex-matched controls, and we also assessed the effect of Roux-en-Y gastric bypass on reflux symptoms and erosive esophagitis. Methods  Between November 2006 and February 2008, 150 morbidly obese Chinese patients underwent laparoscopic Roux-en-Y gastric bypass. Gastroesophageal reflux disease questionnaires and esophagogastroduodenoscopy results were assessed in all cases before surgery. The prevalence of reflux symptoms and erosive esophagitis was compared with the prevalence in a database of 300 age- and sex-matched controls. We also compared baseline and postoperative characteristics at 12 months after operation. Results  Patients with morbid obesity had higher frequencies of reflux symptoms (16% vs. 8%, P = 0.01) and erosive esophagitis (34% vs. 17%, P < 0.01) than those of controls. Twelve months after laparoscopic Roux-en-Y gastric bypass, 26 patients received follow-up evaluations. In addition to substantial weight loss, the prevalence of reflux symptoms and erosive esophagitis decreased significantly after operation (19.2% vs. 0%, P = 0.05, and 42.3% vs. 3.8%, P < 0.01, respectively). Conclusions  Gastroesophageal reflux disease is pervasive in Chinese patients with morbid obesity and Roux-en-Y gastric bypass substantially improves not only the reflux symptoms but also the erosive esophagitis.     

Total fundoplication controls acid and nonacid reflux: evaluation by pre- and postoperative 24-h pH–multichannel intraluminal impedance

Background  Studies have demonstrated that Nissen fundoplication controls acid gastroesophageal reflux (GER). Combined 24-h pH and multichannel intraluminal impedance (MII-pH) allows detection of both acid and nonacid GER. Antireflux surgery is considered for any patient whose medical therapy is not efficient, particularly patients with nonacid gastroesophageal reflux disease (GERD). Nevertheless, fundoplication used to control nonacid reflux has not been reported to date. Methods  In this study, 15 consecutive patients who underwent laparoscopic Nissen-Rossetti fundoplication had MII-pH both before and after the surgical procedure. The numbers of acid and nonacid GER episodes were calculated with the patient in both upright and recumbent positions. Results  The 24-h pH monitoring confirmed the postoperative reduction of exposure to acid (p < 0.05). Postoperatively, the total, acid, and nonacid numbers of GER episodes were reduced (p < 0.05). Conclusion  According to the findings, MII-pH is feasible and well tolerated. It provides an objective means for evaluating the effectiveness of Nissen-Rossetti fundoplication in controlling both acid and nonacid GER.