Proximal Esophageal Acid Research Articles

Esophageal pH-monitoring in nonbrachycephalic dogs; a reference.

To establish parameters that describe acidic gastroesophageal reflux (GER) events in nonbrachycephalic, hospitalized dogs without gastrointestinal disease following short total intravenous anesthesia, to establish upper reference limits for parameters that describe GER. Clinical prospective study. Healthy, client-owned dogs presenting for elective orthopedic surgery. Dogs were sedated with IM methadone (0.2 mg/kg) and medetomidine (5 ug/kg), followed by alfaxalone total intravenous anesthesia. The Digitrapper esophageal dual pH monitoring probe was placed transnasally into the esophagus. Dogs were unsedated during the subsequent recording period. A GER event was defined as esophageal pH less than 4.0. Parameters that described GER were: (1) number of GER events per hour, and (2) cumulative esophageal acid exposure (percentage of recording duration) at each sensor. Upper reference limits were calculated for each parameter. Thirty-five dogs were included (median age 7 years, range 1-12). The median recording duration was 21.1 h (range 13.6-29.3). Productive regurgitation was not noted in any dog. The median number of distal and proximal GER events per hour was 0.3 (range 0-4.3) and 0 (range 0-1), respectively. The median cumulative distal and proximal esophageal acid exposure was 0.2% (range 0.3-9%) and 0% (range 0%-1%), respectively. Upper reference limits for distal and proximal GER per hour was 2.4 and 0.4, respectively, and, for cumulative distal and proximal esophageal acid exposure, 2.3% and 0%, respectively. Dogs undergoing esophageal pH monitoring in a similar hospital setting with parameters above these upper reference limits have excessive GER.

Idiopathic Pulmonary Fibrosis and Gastroesophageal Reflux. Implications for Treatment

BackgroundEven though the pathogenesis of idiopathic pulmonary fibrosis (IPF) is unknown, there is mounting evidence that abnormal reflux (GERD) and aspiration of gastric contents may play a role in the pathogenesis of this disease. AimsThe aims of this study were to determine in patients with GERD and IPF: (a) the clinical presentation, (b) the esophageal function, and (c) the reflux profile. MethodsWe compared the clinical presentation, the esophageal function (as defined by high-resolution manometry), and the reflux profile (by dual sensor pH monitoring) in 80 patients with GERD (group A) and in 22 patients with GERD and IPF (group B). ResultsHeartburn was present in less than 60 % of patients with GERD and IPF. Lower esophageal sphincter pressure and peristalsis were normal in both groups, while the upper esophageal sphincter (UES) was more frequently hypotensive in IPF patients (p = 0.008). In patients with GERD and IPF, the proximal esophageal acid exposure was higher (p = 0.047) and the supine acid clearance was slower as compared with patients with GERD only (p < 0.001). ConclusionsThe results of this study show that in patients with GERD and IPF: (a) reflux is frequently silent, (b) with the exception of a weaker UES, the esophageal function is preserved, and (c) proximal reflux is more common, and in the supine position, it is coupled with a slower acid clearance. Because these factors predisposing IPF patients to the risk of aspiration, antireflux surgery should be considered early after the diagnosis of IPF and GERD is established.

Lower Esophageal Sphincter (LES) Electrical Stimulation Eliminates Proximal Esophageal Acid Exposure in Patients with Proximal GERD - One Year Results

Lower Esophageal Sphincter (LES) Electrical Stimulation Eliminates Proximal Esophageal Acid Exposure in Patients with Proximal GERD - One Year Results

Association Between Proximal Histological Esophagitis and Atypical Reflux Symptoms in Patients with GERD

Purpose: Globus sensation, chest pain, chronic cough are suggested as atypical or extraesophageal manifestations for gastroesophageal reflux disease (GERD). Increased proximal esophageal acid reflux is observed in reflux patients with extraesophageal symptoms. Although histological abnormalities have been described in patients with GERD, the association between proximal esophageal inflammation and atypical reflux symptoms remains unclear. The aim of this study was to investigate the prevalence of atypical symptoms and histological reflux esophagitis (HRE) in patients with GERD. We also addressed the question of whether proximal HRE correlated with these atypical symptoms. Methods: The study involved 92 prospective patients (55 women, age 46, 20-82 yr) with typical symptoms (heartburn and/or regurgitation) suggestive of GERD. Endoscopical evidence of erosive esophagitis was diagnosed according to Los Angeles classification. Endoscopic biopsies were taken 3 cm and 13 cm above the gastroesophageal junction to assess the presence of HRE. Results: Of all GERD patients, there were 28 patients with globus sensation (30.4%), 45 patients with chest pain (48.9%), 32 patients with chronic cough (34.8%). Forty-seven patients were found to have normal endoscopy (NE) (51.1%), and 45 patients with erosive esophagitis (EE) (48.9%). HRE was detected in 48 patients (52.2%) for distal esophagus, whereas 42 patients (45.7%) had proximal histological esophagitis. Distal HRE occurred 23 of 45 patients with EE (51.1%) and 25 of 47 patients with NE (53.2%) (p=NS), while proximal HRE occurred in 19 of 45 patients with EE (42.2%) and 23 of 47 patients with NE (48.9%) (p=NS). No statistical difference was found regarding the prevalence of any atypical symptom between EE and NE patients. Proximal HRE did not correlate well with the presence of any atypical symptom. Conclusion: Atypical reflux symptoms appear to be equally present in patients with and without erosive esophagitis. Histological reflux esophagitis can be detected in both proximal and distal esophagus regardless of the presence of erosive esophagitis as noticed by endoscopy. None of atypical reflux symptoms correlates with proximal histological reflux esophagitis, suggesting that proximal esophageal inflammation may play a limited role, if any, in the generation of these symptoms.

Proximal Esophageal pH Monitoring: Improved Definition of Normal Values and Determination of a Composite pH Score

Patients with respiratory and laryngeal symptoms are commonly referred for evaluation of reflux disease as a potential cause. Dual-probe pH monitoring is often performed, although data on normal acid exposure in the proximal esophagus are limited because of the small number of normal subjects and inconsistent placement of the proximal pH sensor in relation to the upper esophageal sphincter. We measured proximal esophageal acid exposure using dual-probe pH and calculated a composite pH score in a large number of asymptomatic volunteers to better define normal values. Eighty-one normal subjects free of reflux, laryngeal, or respiratory symptoms were recruited. All had video esophagraphy to exclude hiatal hernia. Esophageal pH monitoring was performed using 1 of 3 different dual-probe catheters with sensors spaced 10, 15, or 18 cm apart. The standard components of esophageal acid exposure were measured, excluding meal periods. A composite pH score for the proximal esophagus was calculated using these components. The final study population consisted of 59 (49% male) subjects, with a median age of 27 years. All had normal distal esophageal acid exposure and no hiatal hernia. The 95(th) percentile values for the percent time the pH was < 4 for the total, upright, and supine periods were 0.9%, 1.2%, and 0.4%, respectively. The 95(th) percentile for the number of reflux episodes was 24 and for the calculated proximal esophageal composite pH score was 16.4. In a large population of normal subjects, we have defined the normal values and calculated a composite pH score for proximal esophageal acid exposure. The total percent time pH < 4 was similar to previously published normal values, but the number of reflux episodes was greater.

Gastro-oesophageal reflux and aspiration in patients with advanced lung disease

Numerous small observational studies have shown that gastro-oesophageal reflux is prevalent among patients with advanced lung disease. The fundamental concern is that reflux is a risk factor for recurrent microaspiration, which may cause lung injury. For example, in lung transplant patients, a molecular marker of aspiration was a risk factor for the bronchiolitis obliterans syndrome in one study. To date, however, there are no large prospective studies measuring the impact of aspiration on clinical outcomes. The major obstacle limiting the study of reflux and aspiration in patients with advanced lung disease is the absence of a reliable diagnostic tool. Proximal oesophageal acid detection by pH monitoring is the only widely available measure of aspiration risk. Impedance monitoring may be a superior measure of aspiration risk as it measures both acid and non-acid reflux episodes. Molecular markers of aspiration, such as pepsin or bile salts in the bronchoalveolar lavage or exhaled breath condensate, may be the optimal diagnostic tests, but they are not currently available outside the research setting. Larger observational studies are needed to determine the following: (1) the clinical significance of aspiration in patients with advanced lung disease and in patients who have had lung transplantation and (2) the diagnostic test that best predicts adverse outcomes.

Laryngopharyngeal Reflux: Beauty is in The Eye of The Beholder

Laryngopharyngeal Reflux: Beauty is in The Eye of The Beholder

Diagnostic approach to gastroesophageal reflux disease associated respiratory complications: role of dual channel pH-metry

Aim: to investigate the value of different methods, particularly the usefulness of routine 24-hr dual channel esophageal pH-metry, in the diagnosis of GERD associated respiratory complications. Patients and methods: 100 subjects with GERD associated airway complications were submitted to 24-hr dual channel esophageal pH monitoring, upper gastrointestinal endoscopy, esophageal manometry and video barium esophagography and their symptoms were analysed. Results: 25% of patients (pts) with GERD associated airway complications did not have reflux symptoms. 5cm above LES the DeMeester score was pathological only in 39% of the pts. Additional 10% had a normal DeMeester score, but abnormal postprandial and/or nocturnal reflux activity. Further 50% showed only short reflux episodes at this level. 20cm above the LES, 24-hr pH-monitoring showed pathological reflux activity in only 14% of pts, while proximal reflux episodes were detected in further 68% of the pts. Upper gastrointestinal endoscopy was normal in 18%, revealed NERD in 27% and ERD in 55% of the pts, respectively. Esophageal manometry showed impaired LES function in 63% of the pts. No differences were observed in the results of detailed symptom analysis, endoscopy and LES manometry between patients with or without proximal esophageal acid exposure. However the DeMeester score was abnormal (43% vs. 28%) and barium swallow showed pharyngeal reflux in greater proportion of pts (76% vs. 50%) with proximal esophageal reflux than pts without proximal acid reflux. Conclusions: Dual channel 24-hr pH-monitoring is a valuable method in the diagnosis of GERD induced respiratory complications. It detected pharyngeal reflux in 82% of our pts, while the reflux activity was pathological only in 49% of these pts at the distal sensor. Moreover our results provide evidence that short reflux episodes may have a pathological role in the development of GERD induced respiratory complications.

Effect of oesophagitis on proximal extent of gastro‐oesophageal reflux

Proximal oesophageal acid reflux is increased in gastro-oesophageal reflux disease (GORD) patients with oesophageal and extra-oesophageal symptoms, the latter particularly in presence of oesophagitis. This study was aimed to assess the proximal extent of reflux, both acid and weakly acidic, in GORD patients with and without oesophagitis and to characterize, using an animal model of GORD, the relationship between acute oesophagitis and proximal extent of reflux. Proximal extent of reflux was evaluated during 24-h pH-impedance monitoring in 17 oesophagitis, 27 non-erosive reflux disease (NERD) patients and 10 asymptomatic controls. In five adult cats, reflux events were simulated by intra-oesophageal retrograde injection of a radiopaque solution. Proximal extent of simulated reflux was fluoroscopically assessed before and after inducing acute oesophagitis. The percentage of proximal reflux was 11% in controls, 22% in NERD and 38% in oesophagitis patients (P < 0.05 vs NERD). Weakly acidic reflux showed higher proximal extent in oesophagitis than in NERD patients but it was less proximally propagated than acid reflux. In cats, proximal reflux was significantly increased during acute oesophagitis. Oesophagitis patients show higher proximal extent of reflux, acid and weakly acidic, when compared with NERD patients and controls. In the experimental model, acute oesophagitis favours proximal migration of simulated reflux.

The Utility of Ambulatory pH Monitoring in Patients Presenting with Chronic Cough and Asthma

To evaluate the prevalence of gastroesophageal reflux disease (GERD) in patients presenting with asthma and chronic cough. The charts of 358 consecutive patients who were referred for ambulatory gastroesophageal pH monitoring to the Lung Centre in Vancouver, British Columbia, were reviewed, and the data of 108 (30%) patients with asthma and 134 (37%) patients with chronic cough were analyzed. The maintenance treatment for GERD was discontinued before patients underwent the pH monitoring study. One hundred eighteen (33%) patients were excluded. Reflux episodes identified reflux events as the percentage of time where the pH was less than four. For asthma patients, 70 (64.8%) had distal total reflux, 50 (46.3%) had distal upright reflux, 41 (38.3%) had distal supine reflux and 73 (67.6%) had other distal refluxes. Proximal total reflux in asthmatic patients was present in 56 (52%), proximal upright reflux in 55 (51%) and proximal supine reflux in 56 (52%) patients. For chronic cough patients, 70 (52.6%) had distal total reflux, 59 (44.4%) had distal upright reflux, 45 (34.4%) had distal supine reflux and 75 (56%) patients had other distal refluxes. In chronic cough patients, proximal total reflux was present in 70 (52%), proximal upright reflux in 80 (60%) and proximal supine reflux in 59 (44%). Presenting respiratory and/or reflux symptoms were absent in approximately 25% of patients with asthma and reflux, and in approximately 50% of patients with chronic cough and reflux. During pH monitoring, symptoms did not differ significantly between those with and without distal reflux in both study groups, except for more significant heartburn in patients with chronic cough and reflux (RR 2.0). The data of the present study support the observation that there is a high prevalence of GERD in patients with asthma or chronic cough. The use of different pH parameters for detecting acid reflux during 24 h ambulatory pH monitoring, such as proximal esophageal acid measurement, should be considered as part of the routine interpretation of such testing. A low threshold for diagnosing GERD in patients with asthma or chronic cough is essential, because respiratory and/or reflux symptoms can be absent or atypical in some of these patients.

Effect of hiatal hernia on proximal oesophageal acid clearance in gastro‐oesophageal reflux disease patients

Proximal acid reflux is common in gastro-oesophageal reflux disease and is a determinant of symptoms. Patients with hiatal hernia complain of more symptoms than those without and are less responsive to proton-pump inhibitors. To evaluate the role of hiatal hernia on spatiotemporal characteristics of acid reflux. Thirty seven consecutive gastro-oesophageal reflux disease patients underwent endoscopy, videofluoroscopy, manometry and multichannel 24-h pH test. Data were compared with those of 15 asymptomatic controls. Multivariate linear regression was used for statistical analysis. At videofluoroscopy, hiatal hernia was found in 16 of 37 patients. The mean size of hiatal hernia was 3.4 cm. Patients showed significantly prolonged acid clearance time, both at proximal and distal oesophagus, compared with controls. Hiatal hernia patients showed a significantly delayed acid clearance, along the oesophageal body, compared with non-hiatal hernia patients. The prolonged acid exposure was maintained during upright and supine position. The presence of hiatal hernia significantly predicted acid clearance delay in the distal and proximal oesophagus [at 10 cm below upper oesophageal sphincter: Delta + 2.5 min (95% confidence interval: 0.4-4.5); P < 0.02]. The presence of hiatal hernia is a strong predictor of more prolonged proximal oesophageal acid exposure and clearance. Hiatal hernia is likely to play a role in the pathophysiology of gastro-oesophageal reflux disease symptoms, and should be taken into greater consideration in the treatment strategies of the disease.

Determinants of Long-Term Outcome of Patients with Reflux-Related Ear, Nose, and Throat Symptoms

Gastroesophageal reflux disease (GERD) is present in up to 75% of patients with chronic refractory ear, nose, and throat (ENT) symptoms, and proton pump inhibitor (PPI) therapy induces symptom relief in the majority of these patients. It has been suggested that endoscopic findings and quantification of esophageal acid exposure may help to predict the long-term outcome of medical therapy, but prospective studies that confirm this hypothesis are lacking. The aim of the present study was to investigate the relationship of endoscopic findings and quantification of reflux with long-term outcome in patients with reflux-related ENT symptoms. One hundred six consecutive patients with chronic refractory unexplained ENT symptoms underwent upper GI endoscopy, 24-hr dual-channel esophageal pH and Bilitec (n = 35) monitoring, and esophageal manometry. Subsequently, all were treated with omeprazole, 20 mg b.i.d., and patients were followed at 2-week intervals until symptom relief. Four weeks later, omeprazole therapy was gradually decreased and the lowest effective omeprazole maintenance dose, if any, was determined. Eighty-one patients (49 men; mean age, 50) experienced a clear or excellent therapeutic response after, on average, 4 weeks of omeprazole, 20 mg b.i.d. In 36 patients (44%; group A), PPI treatment could be stopped completely, 27 patients (33%; group B) required a maintenance dose of omeprazole, 20 mg/day, and 18 patients (22%; group C) required maintenance with omeprazole, 40 mg/day. The prevalence of reflux esophagitis was significantly lower in group A patients, who also had significantly lower distal esophageal acid exposure, proximal esophageal acid exposure, and esophageal duodenogastroesophageal reflux exposure compared to groups B and C. Multivariate analysis identified the presence of esophagitis and pathological distal esophageal acid exposure as risk factors for the need of maintenance therapy. In patients with reflux-related ENT symptoms, initial findings on upper GI endoscopy and 24-hr pH-metry help to predict the need for maintenance therapy.

Esophageal Acid Exposure in Healthy Adults in Taiwan: Experience with pH Step-up Method by Dual-Channel pH-metry

Esophageal acid exposure is common in normal subjects. The aim of this study was to investigate proximal and distal esophageal acid exposure in asymptomatic volunteers using dual-channel esophageal pH-metry with probe positioning by pH step-up. A total of 21 healthy subjects (9 male; mean age, 51 years) underwent 24-hour ambulatory esophageal pH recording with the pH step-up method using a two-channel pH probe, a portable digital data recorder, and computerized data analysis. All reflux episodes, episodes longer than 5 minutes, longest reflux episode, duration of acidity (pH <4), and percentage of time with acidity were analyzed. The 95th percentile for reflux parameters assessed in the distal/proximal esophagus were: total reflux episodes, 100/34; episodes greater than 5 minutes, 2.9/0; longest reflux episode, 16.6/2.95 minutes; duration of acidity, 87.95/15.5 minutes; and percentage of time with acidity, 7.0%/1.3%. Proximal and distal acid exposure were well correlated. Results showed that neither gender nor age influenced reflux parameters and that asymptomatic volunteers might experience some gastroesophageal reflux.

Gastroesophageal Reflux (Symptomatic and Silent): A Potentially Significant Problem in Patients With Cystic Fibrosis Before and After Lung Transplantation

The significance of gastroesophageal reflux (GER) and aspiration are unclear in cystic fibrosis (CF) and may contribute to declining lung function before and after lung transplantation (LTx). We sought to establish whether GER occurs in patients with CF on the LTx waiting list and after LTx. We then investigated whether GER correlates with patients' symptoms. Adults with CF on the waiting list and after LTx were prospectively recruited. Completion of a valid, structured symptom questionnaire was followed by ambulatory, dual-probe, 24-hour esophageal pH monitoring. Twenty-four patients were studied, including 11 (6 males) in the pre-LTx group and 13 (9 males) in the post-LTx group. The pre-LTx group was 29.3 +/- 8.2 years of age, and the post-LTx group was 32.7 +/- 8.2 years of age. DeMeester score (normal value <14.7) was 36.6 +/- 22.3 for the pre-LTx group and 40.0 +/- 37.3 for the post-LTx group. Proximal esophageal acid exposure was significantly higher in both CF groups compared with normal. Symptom scores (normal <4, range -2 to 18) were: pre-LTx group, 5.8 +/- 6.5; post-LTx group, 7.7 +/- 5.4. Percent forced expiratory volume in 1 second (FEV1%) predicted was: pre-LTx group, 31.3 +/- 7.8; post-LTx group, 65.2 +/- 29.3. In the pre-LTx group, 10 of 11 (90.9%) patients had significant GER on monitoring, including 4 (40%) with symptomatic GER and 6 (60%) with silent GER. In the post-LTx group, 11 of 13 (84.6%) had significant GER on monitoring, including 9 (82%) with symptomatic GER and 2 (18%) with silent GER. GER, symptomatic and silent, is a significant problem in CF. This condition should be aggressively treated and surgery should be considered if GER persists on re-testing.

Gastroesophageal reflux and gastric emptying, revisited

Total gastric emptying is delayed in 10% to 33% of adult patients with gastroesophageal reflux disease (GERD), but a strong correlation between duration of gastric emptying and severity of acid reflux or esophagitis has never been proved. Previous studies reported that patients with GERD might have exaggerated postprandial fundus relaxation with retention of food and triggering of transient lower esophageal sphincter relaxations (TLESRs). There is a positive correlation between postprandial fundus relaxation and number of TLESRs and also between proximal gastric emptying and esophageal acid exposure. However, new studies suggest that a high number of TLESRs and reflux events may occur even with accelerated gastric emptying, and prolonged gastric retention might be associated with less rather than more esophageal acid exposure. Using simultaneous gastric emptying and esophageal pH impedance we found that the rate of gastric emptying might determine the acidity and proximal extent of reflux: The slower the emptying, the higher the pH and proximal extent of the refluxate.

Characteristics and Clinical Relevance of Proximal Esophageal pH Monitoring

It is well established that various ENT disorders and symptoms may be a manifestation of gastroesophageal reflux disease (GERD). Measuring proximal esophageal acid exposure might be useful in the evaluation of patients with suspected reflux-related ENT manifestations, but the limited available data are conflicting. The aim of the present study was to study the determinants of proximal esophageal acid exposure (PR) and to evaluate the clinical usefulness of ambulatory proximal pH monitoring. Twenty healthy controls and 346 patients with suspected reflux disease underwent typical and atypical GERD symptom assessment, endoscopy, esophageal manometry and ambulatory combined dual esophageal pH, and Bilitec duodeno-gastro-esophageal reflux exposure (DGER) monitoring. The presence of pathological PR and its relation to symptom pattern and distal esophageal acid exposure (DR) and DGER exposure were analyzed. Fifty-seven patients (16%) had pathological PR. Demographic characteristics, symptom pattern, and manometric findings did not differ in patients with normal or pathological PR. Patients with pathological PR had significantly higher DR and DGER. The multivariate analysis identified only pathological DR as an independent risk factor for the presence of pathological PR (odds ratio 4.515, 95% CI 2.48-8.23, p < 0.0001). Only 20 patients (6%) had pathological proximal reflux without pathological distal acid reflux. The findings of the present article do not support routine proximal esophageal pH monitoring as a clinical tool: PR does not differentiate patients with typical or atypical GERD manifestations and depends mainly on DR.

Paroxysmal Laryngospasm: A Typical but Underrecognized Supraesophageal Manifestation of Gastroesophageal Reflux?

Thirty-five consecutive adult patients with paroxysmal laryngospasm (LS) and with unimpaired vocal fold mobility were prospectively studied for coexisting gastroesophageal reflux disease (GERD). Nineteen patients reported frequent (>3 episodes a week) LS episodes (FLS patients) and 16 patients reported occasional LS episodes (OLS patients). All patients underwent an extensive otorhinolaryngological (ORL) examination, upper gastrointestinal (GI) endoscopy, ambulatory 24-hr dual-channel esophageal pH monitoring, and esophageal manometry. In addition, a subset of LS patients also underwent ambulatory duodenogastroesophageal reflux (DGER) monitoring. Patients with daily LS used the symptom marker during pH monitoring indicating separate LS episodes. All FLS patients and 14 OLS patients (87%) had a diagnosis of GERD. Only 10 patients (29%) experienced heartburn and/or regurgitation. Compared to OLS patients, FLS patients generally had more severe GERD as indicated by a higher prevalence of a hiatus hernia, higher distal and proximal esophageal acid exposure times, and higher values of DGER. In six FLS patients, 21 LS episodes (91%) occurred simultaneously with acid reflux, indicating a causal association between LS and GER. On antireflux therapy consisting of omeprazole, 20 mg bid, or lansoprazole, 30 mg oid, and lifestyle measures, LS ceased completely in all patients within 6 weeks. The present study not only demonstrates the role of GER in the pathogenesis of LS and the effectiveness of antireflux therapy, but also suggests that LS in adult patients with unimpaired vocal fold mobility might be considered a typical, although most frequently unrecognized, supraesophageal manifestation of GER.

PSEUDOREFLUX

Purpose: Pseudoreflux is believed to be caused by drying of proximal placed pH electrodes during recumbency due to decreased saliva production and limited swallowing. As the electrode dries, the signal decays resulting in the classic pattern of a gradual decline in pH. This decrease in pH, if not identified as an artifact and excluded, will be read as a reflux episode, and potentially induce over diagnosis. The aim of this study is to identify the frequency of pseudoreflux, and evaluate its effect on interpretation of 24-hour esophageal pH studies. Methods: 200 consecutive dual electrode pH studies (135 females, 65 males; mean age = 50 years; range: 16 – 88) performed in our lab between July 2002 and February 2003 were analyzed for percent time pH <4 at the distal (normal values: total <4.2%; upright <6.3%; recumbent <1.2%) and proximal (normal values: total <1%; upright <1.3%; recumbent = 0) sites. All tracings were re-analyzed to identify episodes of pseudoreflux and acid reflux time recalculated with these episodes included and excluded. Results: 14 patients (7%) showed at least one typical episode of pseudoreflux during their studies. In all these patients, exclusion of the pseudoreflux episodes showed absent proximal recumbent esophageal acid exposure. When the pseudoreflux episodes were included in the analysis, all the patients (100%) had abnormal proximal recumbent esophageal acid exposure (mean: 5.2%; range: 0.4%-13.5%). Only 4 of these patients showed any abnormal esophageal acid exposure when pseudoreflux was excluded. Thus, not excluding pseudoreflux changed the overall diagnosis from a normal to an abnormal study in 72% (10/14) of these patients. There was also a significant difference in recumbent (p = 0.0001) and total (p = 0.0001) proximal esophageal acid exposure when including or excluding the pseudoreflux episodes. Conclusions: Pseudoreflux is seen on a regular basis during 24-hour esophageal pH studies. Ignoring the need to exclude these artifacts will most often lead to over-diagnosing gastroesophageal reflux disease.

Improved outcome after extended gastric myotomy for achalasia.

There is general agreement that a Heller myotomy should extend 6 to 7 cm above the gastroesophageal junction. Results of most previous studies have recommended that the myotomy extend 1 to 1.5 cm below the gastroesophageal junction. We speculated that the effectiveness of the operation could be improved if a longer, 3-cm myotomy was carried out below the gastroesophageal junction, as it would more completely obliterate the lower esophageal sphincter. We, therefore, changed our technique in 1998. Concurrently, we converted from a Dor fundoplication to a Toupet fundoplication. This study analyzes the results of our new strategy. A case series using a prospectively maintained database. Tertiary referral center. One hundred ten consecutive patients with achalasia undergoing laparoscopic Heller myotomy. We analyzed the course of 52 patients treated with a standard laparoscopic esophagogastric myotomy (1.5 cm in the stomach) and a Dor fundoplication between September 1, 1994, and August 31, 1998, and 58 treated with an extended gastric myotomy (3 cm below the gastroesophageal junction) and a Toupet fundoplication between September 1, 1998, and August 31, 2001. Esophageal function testing (esophageal manometry and 24-hour pH monitoring), symptom questionnaire (frequency and severity), and postoperative interventions required. Postoperatively the lower esophageal sphincter pressure was significantly lower after extended gastric myotomy and a Toupet fundoplication vs standard myotomy and a Dor fundoplication (9.5 vs 15.8 mm Hg). Dysphagia was both less frequent (1.2 vs 2.1) and less severe (visual analog scale, 3.2 vs 5.3) after extended gastric myotomy and Toupet fundoplication. In the standard laparoscopic esophagogastric myotomy and a Dor fundoplication group, 9 patients (17%) had recurrent, severe dysphagia, which was treated by dilation in 5 patients and by reoperation in 4 patients. In the extended gastric myotomy and Toupet fundoplication group, 2 patients (3%) developed recurrent dysphagia that resolved with dilatation. There were no reoperations in the extended gastric myotomy and Toupet fundoplication group. No difference was noted in the frequency of heartburn (1.3 vs 1.7), regurgitation (0.3 vs 0.8), and chest pain (0.3 vs 0.6), nor was there a difference between the 2 groups in proximal (1.7% vs 2.3%) and distal (6.0% vs 5.9%) esophageal acid exposure. An extended gastric myotomy (3 cm) more effectively disrupts the lower esophageal sphincter, thus improving the results of surgical therapy for achalasia for dysphagia without increasing the rate of abnormal gastroesophageal reflux provided that a Toupet fundoplication is added.

Proximal esophageal acid exposure is associated with hypertensive contractions in the distal esophagus

Proximal esophageal acid exposure is associated with hypertensive contractions in the distal esophagus