Bravo Capsule Research Articles

Twenty-four-hour pH metry alone is inferior to additional impedance monitoring in the diagnosis of gastroesophageal reflux disease, particularly in presence of reduced gastric acid secretion.

Current gold standard for the diagnosis of gastroesophageal reflux disease (GERD) is 24-hour pH metry though it fails to detect non-acidic reflux. The sensitivity of 24-hour pH metry alone (both catheter-based and Bravo capsule) is questionable, especially if gastric acid secretion is low due to reduced parietal cell mass, Helicobacter pylori-induced gastric atrophy and antisecretory therapy. Accordingly, we analyzed the diagnostic ability of 24-hour pH metry as compared to impedance monitoring in relation to the gastric pH without antisecretory therapy. A retrospective analysis of prospectively collected data from 150 patients with suspected GERD undergoing a 24-hour pH impedance study was done. Among 150 patients with symptoms suggestive of GERD, 106 (70.6%) had confirmed GERD diagnosed either by 24-hour pH metry alone (10 [9.4%]), impedance monitoring alone (49 [46.2%]) or both (47 [44.3%]). Abnormal reflux of acidic and non-acidic gastric contents was detected by 24-hour pH metry and 24-hour impedance monitoring in 57/106 (53.7%) and 96/106 (90.5%) of patients, respectively (p < .00001). Patients with GERD diagnosed by 24-hour impedance monitoring had a higher mean gastric pH (2.9 [median 1.3, IQR 5.3]) than those diagnosed by 24-hour pH metry (2.1 [median 1.4, IQR 2.6]) or both (1.6 [median 1.2, IQR 2.1]) (p = 0.001). Twenty-four-hour impedance monitoring detects GERD more often than 24-hour pH metry. Patients with higher mean gastric pH leading to non-acidic reflux were more often diagnosed by 24-hour impedance monitoring than 24-hour pH metry. Thus, 24-hour pH metry alone is inferior to additional impedance monitoring in the diagnosis of GERD, particularly in presence of reduced gastric acid secretion.

Patient adverse events and technical failures with the bravo capsule pH system: insights from the MAUDE database.

The BRAVO pH monitor system can benefit patients with ongoing GERD symptoms despite treatment and/or atypical symptoms. We aim to investigate the number and type of complications associated with the BRAVO pH capsule. From April 2016 through February 2021, we analyzed post-marketing surveillance data from the FDA Manufacturer and User Facility Device Experience (MAUDE) database. During the study period, approximately 1,651 reports were identified with 2391 cases associated with a device failure, and 254 reporting a patient-related adverse event. Most device complications were due to aspiration n = 153), followed by reported pain (n = 79), injury (unspecified) (n = 63), and additional radiologic imaging (n = 44). Laceration and bleeding accounted for 29 and 19 cases. Furthermore, three patients suffered perforation. Most device failures were due to loss or failure of the Bravo capsule to bond or adhere to the esophageal mucosa as planned (n = 1269), followed by an activation or positioning failure (n = 972), premature detachment of device (n = 284), and failure of the device to record or transmit data (n = 158). Findings from the MAUDE database highlight the risk of aspiration, hemorrhage/bleeding, perforation, injury, and retention as potential complications of BRAVO capsule placement.

S2274 Bravo Capsule Aspiration

Introduction: Bravo wireless capsule is a catheter-free pH monitoring system used to diagnose GERD in patients who fail anti-secretory therapy. Several adverse events have been reported in the literature; these include nose or throat discomfort and dislocation from positioned sites. Case Description/Methods: A 72-year-old man with a history of GERD, prostate cancer, hypothyroidism, obstructive sleep apnea, presented for esophagogastroduodenoscopy (EGD) with Bravo™ placement due to persistent esophageal reflux symptoms despite appropriate therapy. The Bravo™ capsule (Medtronic, Minneapolis, MN) with a delivery system was introduced through the mouth and advanced into the esophagus. The device was placed with visual confirmation; however, the patient had severe a coughing fit. Suction was applied and the delivery system was then withdrawn. Repeat EGD was performed and no Bravo™ was seen in esophagus, stomach, or duodenum. Due to suspicion of dislodgement, a chest x-ray was performed and Bravo™ was seen in the left lung (figure 1, panel A). The patient was admitted to the hospital, and the pulmonology service was consulted for device removal. Bronchoscopy was performed successfully with the extraction of a capsule from the left main bronchus (Figure 1, panel B). After 24 hours observation, the patient did not have any symptoms or signs of aspiration pneumonitis and was discharged home. Discussion: We present a case of an adult patient with aspiration of the capsule into the lungs. This is an unusual complication with pH monitoring techniques(3). Given the limited number of cases of Bravo™ aspiration, there are no definite guidelines or gold-standard treatment up to date. A patent airway and good oxygenation must be maintained. The initial diagnostic evaluation includes chest radiographs, since the Bravo™ capsule is radiopaque(4).Once located, bronchoscopic tools can usually reveal the capsule, as was done with our patient.Figure 1.: Panel A, left: X-ray showing bravo capsule in left lung panel B, right: bronchoscopy showing reveals bravo capsule in left main bronchus.

The Additional Role of Symptom-Reflux Association Analysis of Diagnosis of Gastroesophageal Reflux Disease Using Bravo Capsule pH Test

Since the development of ambulatory esophageal pH monitoring test to diagnose gastroesophageal reflux disease (GERD), several parameters have been introduced. The aim of this study was to assess whether using the symptom index (SI), symptom sensitivity index (SSI), and symptom association probability (SAP), in addition to the DeMeester score (DS), would be useful for interpreting the Bravo pH monitoring test. A retrospective study, which included 68 patients with reflux symptoms refractory to proton pump inhibitor (PPI) therapy who underwent a Bravo capsule pH test between October 2006 and May 2015, was carried out. Acid reflux parameters and symptom reflux association parameters were analyzed. The median percent time of total pH<4 and DS were 2.90% (interquartile range [IQR] 1.13-6.03%) and 11.10 (IQR 4.90-22.80), respectively. According to the analysis of the day-to-day variation in percent time of total pH<4 (r=0.724) and DS (r=0.537), there was a significant correlation between Day 1 and Day 2. The positive rate of Bravo test according to DS was 27 (39.7%). Although thirty patients experienced symptoms during the test, there were no significant differences of reflux parameters compared with other patients. In the symptom group, 7 patients (23.3%) were identified as having negative DS and an abnormal symptom-related index. There were no significant test-related complications. In addition to the analysis of traditional acid parameters of the Bravo capsule pH test, diagnosis of GERD, including reflux hypersensitivity, can be improved by performing an analysis of the symptom-reflux association and of the day-to-day variation.

Usefulness of the Bravo Capsule pH Monitoring System in the Differential Diagnosis of Gastroesophageal Reflux Diseases

Usefulness of the Bravo Capsule pH Monitoring System in the Differential Diagnosis of Gastroesophageal Reflux Diseases

PTU-120 Extended Bravo Studies (&gt;48 HRS) Improves Diagnostic Yield of Gastro-Oesophageal Reflux Disease (GORD) In Patients with Normal Multichannel Intraluminal Impedance-PH (MII-PH) Studies

Introduction MII-pH catheter studies measure both acid and non-acid reflux and are considered by some to be the gold standard in the diagnosis of GORD. Wireless pH capsule (Bravo) may increase the diagnostic yield of standard 24 hr catheter-based studies by overcoming the limitation of day-to-day reflux variability. This study aims to assess the additional diagnostic yield of extended Bravo recordings (up to 96 hours) in patients with normal 24 hr MII-pH results. Methods A total of 44 patients with typical GORD symptoms but negative 24 hr MII-pH studies off proton pump inhibitor(PPI) were referred for Bravo capsule studies. Bravo studies were performed beyond 48 hrs (up to 96 hrs). Bravo analysis was conducted using the ‘Worst Day Analysis’ (WDA) and ‘Average Day Analysis’ (ADA). Reference values for MII-pH and Bravo equivalent were adopted from internationally established studies (Table 1). Subgroup analyses were made on cohorts whose MII-pH showed normal AET with (A) normal number of total reflux events (TRE), (B) normal number of non-acid reflux (NAR) events and (C) increased number of NAR events. Statistical analysis was performed using SPSS V20. Results Our study group (male = 14, female =30) successfully completed Bravo studies up to 96 hours in 77.3% and beyond 48 hours in 97.7%. Using the WDA and ADA respectively, Bravo (AET cut-off >4.2%) captured an additional 59.1% and 43.2% of patients with increased AET (p Conclusion Extended Bravo studies (>48hours) diagnosed GORD in more than half of cases with an initial normal MII-pH. Half of those with increased NAR events on MII-pH showed positive acid reflux on prolonged Bravo. This additional yield can alter diagnosis from functional heartburn/hypersensitive oesophagus to GORD in difficult cases and influence management. Disclosure of Interest None Declared

PWE-073 Comparison of Cost-Effectiveness Between 96 Hour Wireless Bravo Reflux Monitoring and 24 Hour PH-Impedance in The Diagnosis of Gastroesophageal Reflux Disease: Abstract PWE-073 Table 1

Introduction 24 hour pH-impedance reflux monitoring is considered the gold standard in diagnosing pathological gastroesophageal reflux (GOR). Alternative method is catheter-free Bravo capsules (96 hours). To date, their cost-effectiveness has yet to be compared. At Guy’s Hospital, London, UK, the cost of Bravo is estimated to be £1,200 (including endoscopy) and pH-impedance to be £800 (including high resolution manometry). It is generally assumed that the higher cost of Bravo monitoring is justifiable as it is thought to have a higher diagnostic yield due to better patient compliance and a longer monitoring time. Methods Patients who had a Bravo or pH-impedance study during May-November 2015 were selected. The more cost-effective method was defined as the technique with lower cost (including cost of non-diagnostic results) per diagnostic procedure. To identify non-diagnostic results, the patients with pathological GOR, patients with positive symptom-reflux associations, patients with supragastric belching and patients who were adequately symptomatic (therefore having negative symptom-reflux association) were removed. Positive symptom-reflux association was considered as symptom association probability (SAP) ≥95% and/or symptom index (SI) ≥50%. Results 81 Bravo patients and 145 pH-impedance patients were analysed. 50 (61.7%) Bravo patients and 69 (47.5%) pH-impedance patients were diagnosed with pathological GOR, 14 (17.3%) Bravo and 44 (30.3%) pH-impedance patients had hypersensitive oesophagus, 3 (2.1%) pH-impedance were patients diagnosed with supragastric belching causing symptoms, and 10 (12.3%) Bravo and 14 (9.7%) pH-impedance patients experienced symptoms unexplained by reflux events (negative symptom-reflux association). The remaining 7 (8.6%) Bravo and 15 (10.3%) pH-impedance entries therefore represent the proportion of non-diagnostic investigations. Cost calculations revealed that each Bravo with diagnostic yield costs £1313.5 whilst each pH-impedance with diagnostic yield costs £892.3 (Table 1). This means that for each diagnosis made by Bravo there is an additional cost of £421.2. Conclusion The cost-effectiveness of pH-impedance reflux monitoring seems to be superior to Bravo system to make a reflux-related diagnosis. However, this study does not take into account other advantages of each method in clinical use. Disclosure of Interest None Declared

Sa1300 Clinical and Diagnostic Value of 96 Hours Wireless Reflux Monitoring Off/On PPIs

Introduction Prolonged catheter-free pH monitoring with Bravo capsule up to 96 hours has become possible and enables extended physiological evaluation of gastroesophageal reflux disease (GERD) and response to therapeutic interventions. Aim of the present study was to determine the feasibility of 96 hrs recordings using Bravo capsule that would encompass time periods both off and on therapy with Proton Pump Inhibitors (PPIs). Methods A total of 432 patients reporting symptoms of GERD refractory to conventional therapy underwent 96 hours of Bravo capsule recordings. Patients identified with abnormal acid exposure during the 1st 48 hrs of recordings (off PPIs) underwent the 2nd 48 hrs of recording on twice daily PPIs. The parameters subjected to analysis were percent of time ph Results 132/436 (30.3%) of patients had abnormal acid exposure in the 1st 48 hrs (70 males, mean age 49, range 17–81 years) and the second 48 hrs of recordings was performed on PPIs.98/132 (74.2%) had normal acid exposure on PPIs whereas 34/132 (23.5%) had abnormal acid exposure despite high dose of PPIs. The overall number of symptoms reported in the 2nd 48 hrs was reduced by 68.4% (responsive 76.7% vs refractory 49.9%, p Conclusion Extended pH recording improves the detection of abnormal acid reflux. Combined off and on PPI therapy pH testing provides additional information which can be helpful in the management of patients with PPI refractory GERD. Disclosure of Interest None Declared

Sa1301 Prolonged pH Monitoring With BRAVO Capsule for 96hrs Off/On PPIs Identifies Patients That Could Benefit From More Aggressive Treatment With Acid Suppression

Sa1301 Prolonged pH Monitoring With BRAVO Capsule for 96hrs Off/On PPIs Identifies Patients That Could Benefit From More Aggressive Treatment With Acid Suppression

The Role of the Acid Pocket in Gastroesophageal Reflux Disease.

Gastroesophageal reflux disease is one of the commonest chronic conditions in the western world and its prevalence is increasing worldwide. The discovery of the acid pocket explained the paradox of acid reflux occurring more frequently in the postprandial period despite intragastric acidity being low due to the buffering effect of the meal. The acid pocket was first described in 2001 when it was detected as an area of low pH immediately distal to the cardia using dual pH electrode pull-through studies 15 minutes after a meal. It was hypothesized that there was a local pocket of acid close to the gastroesophageal junction that escapes the buffering effect of the meal, and that this is the source of postprandial acidic reflux. The presence of the acid pocket has been confirmed in other studies using different techniques including high-resolution pHmetry, Bravo capsule, magnetic resonance imaging, and scintigraphy. This review aims to describe what we know about the acid pocket including its length, volume, fluid constituents, and its relationship to the lower esophageal sphincter and squamocolumnar junction. We will discuss the possible mechanisms that lead to the formation of the acid pocket and examine what differences exist in patients who suffer from acid reflux. Treatments for reflux disease that affect the acid pocket will also be discussed.

Low esophageal mucosal blood flow in patients with nutcracker esophagus

Nutcracker esophagus (NE) is characterized by high-amplitude peristaltic esophageal contractions, and these patients often present with symptoms of "angina-like" or noncardiac chest pain. Tissue ischemia is a known cause of visceral pain, and the goal of our present study was to determine whether esophageal wall blood perfusion (EWBP) is reduced in patients with NE. Fourteen normal subjects (mean age 51 yr, 11 men) and 12 patients (mean age 53 yr, 9 men) with NE and noncardiac chest pain were investigated. The EWBP was measured continuously using a custom-designed laser Doppler probe tethered to a Bravo capsule, which anchored it to the esophageal wall. The baseline EWBP in normal subjects was 651 ± 27 perfusion units. In patients with NE, the baseline EWBP was significantly lower than in the normal subjects (451 ± 32 perfusion units). The EWBP decreased after injection of edrophonium (which increases muscle contractions) and increased following sublingual nitroglycerin administration (which relaxes muscle) in normal subjects, as well as in NE patients. Spontaneous pain events during the recording period were often associated with drops in the EWBP. We propose that low EWBP leads to hypoxia of the esophageal tissue, which may be a mechanism of esophageal pain in patients with NE.

Endoscopic Removal of Bravo® pH Probe: Report of Two Cases

Introduction: The Bravo pH monitoring system is widely used to further investigate the patients with refractory or atypical GERD. The pH probe is attached by deploying a locking pin that is passed through the esophageal mucosa and pulled by appropriate suction into a small cup in the side of the probe. Subsequently, the probe sloughs spontaneously from the mucosa within 1-2 weeks and passes uneventfully through the GI tract. Most patients have no or mild symptoms while the probe is attached, but more severe chest pain, odynophagia, or dysphagia occurs in about 10% of patients. We report two rare cases of patients requiring endoscopic removal of Bravo pH probe. Case 1: 34 year-old female who presented with persistent heartburn despite maximal acid-suppressive therapy underwent endoscopic placement of Bravo pH probe at 6 cm proximal to GEJ. One hour after the procedure, the patient complained of significant chest pain at the site of Bravo pH monitoring probe and after 3 hours, the pain was persistent with no change in severity. Repeat endoscopy was performed. The Bravo pH probe was identified. A cold snare was placed around Bravo pH probe but was unsuccessful at removal. A hot snare was used and Bravo capsule probe was dislodged and advanced to stomach. Probe was snared and removed with endoscope via mouth. Patient's pain resolved immediately. Case 2: 37 year-old male who had persistent chronic mild-to-moderate heartburn even after treatment with maximal proton-pump inhibitor for appropriate duration underwent endoscopic placement of Bravo pH probe at 6 cm proximal to GEJ. However, due to technical difficulties, the probe did not register with the monitor. Subsequently, another EGD was performed and the Bravo pH probe was removed via hot snare, after cold snare was again unsuccessful, and removed via mouth. A second Bravo pH probe was placed successfully and was working properly. Discussion: Bravo pH probes may require removal in certain situations. These cases show that both cold and hot snare techniques are safe and simple endoscopic procedures for the removal of the Bravo pH probe. We recommend the cold snare method as a first option with the hot snare method in cases the former fails.

Sexual activity does not predispose to reflux episodes in patients with gastroesophageal reflux disease.

The role of sexual activity on gastroesophageal reflux disease (GERD) is an under-recognized concern of patients, and one rarely assessed by physicians. The objective of this article is to determine the influence of sexual activity on the intraesophageal acid exposure and acid reflux events in GERD patients. Twenty-one patients with the diagnosis of GERD were prospectively enrolled. Intraesophageal pH monitoring was recorded for 48 hours with a Bravo capsule. All patients were instructed to have sexual intercourse or abstain in a random order two hours after the same refluxogenic dinner within two consecutive nights. Patients were requested to have sex in the standard "missionary position" and women were warned to avoid abdominal compression. The patients completed a diary reporting the time of the sexual intercourse and GERD symptoms. The percentage of reflux time and acid reflux events were compared in two ways: within 30 and 60 minutes prior to and after sexual intercourse on the day of sexual intercourse and in the same time frame of the day without sexual intercourse. Fifteen of 21 GERD patients were analyzed. The percentage of reflux time and number of acid reflux events did not show a significant difference within the 30- and 60-minute periods prior to and after sexual intercourse on the day of sexual intercourse and on the day without sexual intercourse, as well. Sexual activity does not predispose to increased intraesophageal acid exposure and acid reflux events. Larger studies are needed to confirm our findings in patients who define reflux symptoms during sexual intercourse.

Clinical value of wireless pH-monitoring of gastro-esophageal reflux in children before and after proton pump inhibitors.

BackgroundWireless pH-monitoring is an accurate method for diagnosing adults with gastroesophageal reflux disease (GERD). The aim of this study was to evaluate the use of the Bravo capsule on children investigated for GERD in terms of safety, tolerability and feasibility before and after administration of proton pump inhibitors.MethodsA Bravo capsule was inserted during upper endoscopy under general anaesthesia or deep sedation with propofol. 48-hour pH-metry was performed in 106 children (50 males, 56 females) at the median age of 11 years (range 17 months-18 years). On the second day of investigation, proton pump inhibitor (PPI) was given at a mean dose of 1.6 mg/kg (SD ±0.6 mg). The definition of GERD was set to a reflux index (RI) of ≥5% and DeMeester score (DMS) ≥14.7.ResultsApplication of the capsule was successful in 103 of the 106 children (97.2%) and interpretable in 99 of these 103 (96.1%). 49 of the children with interpretable results (49.5%) had GERD according to RI, while 51 (56.7%) had GERD according to DMS. After PPI was given on day 2, RI decreased from a median of 4.9% (range 0.3-63.4%) to 2.2% (0–58.0%), while DMS decreased from a median of 17.6 (range 2.2-207.6) to 8.2 (0.3-178.6), respectively (p < 0.0001). No severe adverse events were reported.ConclusionWireless pH-metry is a safe and tolerable method when investigating children for GERD. PPI given on the second day of assessment provides additional information on response to treatment suggesting that pH-metry preferably should be extended to 48 hours.

PTU-140 The Effect of Proton Pump Inhibitors (PPIS) on Oesophageal Acid Reflux using a Prolonged Wire-Less Bravo PH Monitoring

IntroductionRecently prolonged catheter-free pH monitoring (Bravo®, Given Imaging, Yoqeam, Israel) up to 96 hours has become possible which enables more physiological evaluation of oesophageal acid exposure and its response to...

Effect of Propofol on Acid Reflux Measured with the Bravo pH Monitoring System

Background/Aim. The aim of this study was to determine the effect of propofol on acid reflux as measured with the Bravo pH monitoring system. Methods. 48-hour pH tracings of 88 children were retrospectively evaluated after placement of the Bravo capsule under propofol. Comparisons between day 1 and day 2, as well as 6-hour corresponding segments from day 1 and day 2, were made. Results. The number of reflux episodes was significantly increased during the first six-hour period on day one as compared to day 2 (P = 0.006). The fraction of time the pH was <4 was also increased during this period, though it did not reach statistical significance. When comparing full 24-hour periods, there was no difference noted in either the number of reflux episodes or the fraction of time pH < 4 between day one and day two. Conclusion. Our data suggest an increase in gastroesophageal reflux during the postanesthesia period. This could be a direct effect of propofol, or related to other factors. Regardless of the cause, monitoring of pH for the first 6 hours following propofol administration may not be reliable when assessing these patients. Monitoring pH over a prolonged 48-hour time period can overcome this obstacle.

Wireless oesophageal pH monitoring: Establishing values in a multiracial cohort of asymptomatic Asian subjects

Wireless oesophageal (Bravo) readings in healthy European and American subjects show varied results. Values in Asians remain unstudied. We performed Bravo studies in healthy Asians to determine if values differed from previously published and identified reflux parameters to differentiate healthy volunteers from patients. Fifty healthy volunteers were recruited between August 2009 and August 2011 to undergo 48 h wireless pH monitoring. Bravo capsule was introduced transorally and placed 6 cm above the squamocolumnar junction. Acid reflux parameters were compared against 41 patients previously evaluated for non-erosive reflux disease. Five volunteers were excluded. Capsule dislodgement occurred in four and three volunteers on study days 1 and 2 respectively. Forty and 37 volunteers (73% male, mean age 33.0 ± 7.6 years) had interpretable readings at 24 and 48 h, respectively. Percentage of time oesophageal pH<4 in 37 volunteers who completed 48 h recordings was 1.6% (7.5%), 1.5% (6.3%) and 1.9% (5.8%) on days 1, 2 and overall study duration, respectively. Bravo readings in Asians differed from previously published. Percentage of time oesophageal pH<4 on day 2 and DeMeester score on day 2 (95th percentile 22.9) best discriminated healthy volunteers from patients.

The type 2 CCK/gastrin receptor antagonist YF476 acutely prevents NSAID-induced gastric ulceration while increasing iNOS expression

YF476 differs from the proton pump inhibitor (PPI) esomeprazole in mode of action by antagonizing the type 2 receptor of cholecystokinin/gastrin (CCK-2R). YF476 protection against diclofenac-induced gastric ulcers was compared to esomeprazole and correlated with plasma levels of hormones related to gastric pH (gastrin, ghrelin, and somatostatin), gastric gene expression of these hormones, their receptors, and inducible nitric oxide synthase (iNOS). YF476 or esomeprazole pretreatments were followed by diclofenac. Four hours later, gastric tissue was excised and analyzed for ulcer index. An intragastrically implanted Bravo capsule measured pH for 5days during YF476 plus pentagastrin treatment. Changes in gene expression were assayed for gastrin, ghrelin, and somatostatin; their receptors; and iNOS. YF476 acutely (within 4h) protected against diclofenac-induced gastric ulcers equivalent to esomeprazole. Gastric pH recorded during 5days in the presence of pentagastrin was 1.83 (±0.06). YF476 raised pH to 3.67 (±0.09) and plasma ghrelin, gastrin, and somatostatin increased. YF476 increased gene expression of somatostatin receptor and gastrin, while ghrelin receptor decreased; transcripts coding ghrelin, somatostatin, and CCK-2R remained unchanged. In the presence of diclofenac, esomeprazole increased expression of all these transcripts and that of iNOS, while YF476 yielded only decreased CCK-2R and increased iNOS transcripts. YF476 is a potential new preventative treatment for patients at risk of nonsteroidal antiinflammatory drug (NSAID)-induced ulceration. Gastric gene expressions of ghrelin, gastrin, and somatostatin and their receptors differ between esomeprazole and YF476. Despite these differences and different modes of action to raise gastric pH, both drugs acutely increase iNOS, suggesting iNOS expression parallels pH.

An Unusual Complication of Bravo pH Capsule Dislodged into the Pyriform Sinus

Purpose: Wireless esophageal pH monitoring is an important diagnostic modality in patients with suspected gastroesophageal reflux disease (GERD) to confirm acid reflux and evaluate refractory symptoms. The device is commonly placed 6 cm above the endoscopically visualized gastroesophageal junction Z line. After deployment, the attachment and correct positioning on the esophageal wall is frequently confirmed with second look endoscopy. A 44-year-old man with history of GERD symptoms was non-adherent to anti-reflux therapy and developed worsening of his reflux symptoms. In addition to recommendations for antireflux diet and lifestyle modification, he was scheduled for esophagogastroduodenoscopy and Bravo pH testing off acid suppressing medications to confirm presence of acid reflux. The procedure was performed under monitored anesthesia care (MAC). The Z line was visualized at 40 cm from the incisors and the capsule was deployed at 34 cm. The procedure adhered to the manufacturer's protocol. The capsule was not visualized endoscopically attached to the esophageal wall at 34 cm and so the scope was advanced to see if it had migrated to the distal esophagus or into the stomach. The scope was withdrawn proximally after failure to see the capsule at either location. On withdrawal of the scope from upper esophageal sphincter, the capsule was visualized in the left pyriform sinus. It was presumed that the capsule either had been either dragged up by the side of the scope during withdrawal or that the patient had coughed it up. The options for safe removal of the capsule were reviewed in immediate consultation with ENT, and pulmonary physicians. The anesthesiologist provided additional sedation and endotracheal intubation after which the capsule was successfully retrieved by ENT. We report an unexpected, and so far unreported, complication of a Bravo capsule dislodgement. Bravo pH probe placement is generally a safe and well-tolerated procedure. Common complications include non-attachment, misplacement, early dislodgement, poor data reception and capsule removal in patients with intolerable chest pain. Other rare but more serious complications which have been described are esophageal wall trauma, severe bleeding, esophageal perforations, and capsule aspiration into the bronchus. Gastroenterologists performing this procedure should be aware of the low but non-negligible technical difficulties.

Gastric pH and Gastric Residence Time in Fasted and Fed Conscious Beagle Dogs using the Bravo® pH System

To further characterize the time course of gastric pH with respect to meals and gastric residence times (GRTs) in dogs, continuous pH measurements were recorded with Bravo capsules, which were attached to the dogs' stomach mucosa or administered as free capsules, respectively. Experiments took place in home or study cages, and meals were administered at designated times. Up until 2 h prior to mealtime, the fasted gastric pH remained constantly acidic (∼2.0) regardless whether the dogs were in the study or home cages. However, as feeding time became imminent, the pH was typically elevated for dogs in home cages, whereas the pH remained acidic for dogs in study cages. For both monitoring locations, the gastric pH remained acidic during meal consumption and for at least 10 h after meals. The GRT between fasted (25 ± 32 min) and fed (686 ± 352 min) conditions was significantly different with considerable inter- and intrasubject variability. Fasted gastric pH was similar to that of literature monkey and human values but differed after meals as the dog gastric pH remained acidic unlike monkey and human. In dogs, the fasted GRT was remarkably rapid and under fed conditions, longer than that observed in humans.