Use and utility of the Bravo pH capsule

Piloting an intraoral pH device to track gastroesophageal reflux in adults

This study evaluated in vivo, an intraoral device against the gold standard esophageal device for gastroesophageal reflux disease (GERD) monitoring. Subjects scheduled for a catheter-based esophageal pH/impedance testing at a gastroenterology clinic were recruited. They were screened using the GerdQ questionnaire, demographics and dental conditions recorded. A prototype intraoral device, consisting of a Bravo™ capsule embedded in an Essix-style retainer fabricated for each subject, monitored intraoral pH. Concurrently, subjects underwent 24-h esophageal pH-impedance monitoring. A self-administered survey elicited the comfort and acceptance of both devices. The study recruited ten adult subjects (23 to 60-years-old) with a median GerdQ score of 9.5 corresponding to a 79% likelihood of GERD. Subjects with severe dental erosion had significantly (p < 0.05) higher acid exposure time and more non-meal reflux events. No adverse events were associated with the intraoral device while one was recorded for the esophageal device. The intraoral device was significantly more comfortable to place, more comfortable to wear, and interfered less with daily routine compared to the esophageal device. Accuracy of the intraoral device ranged between 86.15% and 37.82%. Being more tolerable than traditional esophageal pH monitoring, intraoral pH monitoring may be a useful adjunct for the diagnosis and management of GERD.

Foreign Body in the Bronchus Intermedius: Inadvertent Deployment of a Bravo Wireless pH Probe in the Airway

The Bravo pH probe is a wireless capsule allowing remote quantification of gastroesophageal reflux. A 14-year-old male presented for Bravo probe placement. Following esophagogastroduodenoscopy, attachment of the Bravo probe was attempted. Immediately, the patient began coughing without oxygen desaturation. Repeat endoscopy did not reveal the probe within the esophagus or stomach. He was then intubated, and fluoroscopy demonstrated a foreign body within the bronchus intermedius. Rigid bronchoscopy was performed to retrieve the probe using optical forceps. This is the first case of pediatric inadvertent airway deployment requiring retrieval. We recommend endoscopic visualization of the delivery catheter entering the cricopharyngeus before Bravo probe deployment, then followed by repeat endoscopy to confirm position of the probe after attachment.

Role of Endoscopy in Motility Disorders of Upper Gastrointestinal Tract

Gastrointestinal motility disorders have a wide range of symptoms and affect patients' quality of life. With the advancement of endoscopy, the diagnostic and therapeutic roles of endoscopy in motility disorders is becoming more significant. Endoscopy is necessary to rule out possible organic diseases in patients with suspected motility disorders and provide significant clues for their diagnosis. Moreover, interventional endoscopy may be a primary or alternative treatment option for selected patients with motility disorders, and it is becoming a promising field as new therapeutic applications are developed and utilized for various motility disorders. This review may provide suitable indications for the use of endoscopy in diagnosing and treating motility disorders of the upper gastrointestinal tract.

Optimal Wireless Reflux Monitoring Metrics to Predict Discontinuation of Proton Pump Inhibitor Therapy

INTRODUCTION

Ambulatory reflux monitoring performed off proton pump inhibitor (PPI) is the gold standard diagnostic test for nonerosive gastroesophageal reflux disease (GERD). However, the diagnostic metrics and optimal duration of monitoring are not well defined. This study evaluated the performance of multiple metrics across distinct durations of wireless reflux monitoring off PPI against the ability to discontinue PPI therapy in patients with suboptimal PPI response.

METHODS

This single-arm clinical trial performed over 4 years at 2 centers enrolled adults with troublesome GERD symptoms and inadequate response to > 8 weeks of PPI. Participants underwent 96-hour wireless pH monitoring off PPI. Primary outcome was whether the subject successfully discontinued PPI or resumed PPI within 3 weeks.

RESULTS

Of 132 participants, 30% discontinued PPI. Among multiple metrics assessed, total acid exposure time (AET) of 4.0% performed best in predicting PPI discontinuation (odds ratio 2.9 [95% confidence interval 1.4, 6.4]; P = 0.006), with other thresholds of AET and DeMeester score performing comparably. AET was significantly higher on day 1 of monitoring compared with other days, and prognostic performance significantly declined when only assessing the first 48 hours of monitoring (area under the curve for 96 hours 0.63 vs area under the curve for 48 hours 0.57; P = 0.01).

DISCUSSION

This clinical trial highlights the AET threshold of 4.0% as a high-performing prognostic marker of PPI discontinuation. 96 hours of monitoring performed better than 48 hours, in predicting ability to discontinue PPI. These data can inform current diagnostic approaches for patients with GERD symptoms who are unresponsive to PPI therapy.

Clinical role of ambulatory reflux monitoring in PPI non-responders: recommendation statements

BACKGROUND

Optimal ambulatory reflux monitoring methodology in symptomatic reflux patients continues to be debated.

AIMS

To utilise published literature and expert opinion to develop recommendation statements addressing use of ambulatory reflux monitoring in clinical practice METHODS: The RAND Appropriateness Method (RAM) was utilised among 17 experts with discussion, revision and two rounds of ranking of recommendation statements. Ambulatory reflux monitoring protocol, methodology and thresholds ranked as appropriate by ≥80% of panellists met the criteria for appropriateness.

RESULTS

Prolonged (96-h recommended) wireless pH monitoring off proton pump inhibitor (PPI) was identified as the appropriate diagnostic tool to assess the need for acid suppression in patients with unproven gastro-oesophageal reflux disease (GERD) and persisting typical reflux symptoms despite once-daily PPI. Acid exposure time (AET) <4.0% on all days of monitoring with negative reflux-symptom association excludes GERD and does not support ongoing PPI treatment. Conversely, AET >6.0% across ≥2 days is conclusive evidence for GERD and supports treatment for GERD, while AET >10% across ≥2 days identifies severe acid burden that supports escalation of anti-reflux treatment. In previously proven GERD, impedance-pH monitoring on PPI is helpful in defining refractory GERD and mechanisms of continued symptoms; the presence of <40 reflux events, AET <2.0% and a negative reflux-symptom association does not support escalation of anti-reflux treatment. In contrast, AET > 4.0% and positive reflux-symptom association support escalation of anti-reflux treatment, including use of invasive therapeutics.

CONCLUSIONS

Statements meeting appropriateness for average clinical care have been identified when utilising reflux monitoring in patients with typical reflux symptoms and PPI non-response.

Connected healthcare: Improving patient care using digital health technologies

Now more than ever, traditional healthcare models are being overhauled with digital technologies of Healthcare 4.0 increasingly adopted. Worldwide, digital devices are improving every stage of the patient care pathway. For one, sensors are being used to monitor patient metrics 24/7, permitting swift diagnosis and interventions. At the treatment stage, 3D printers are under investigation for the concept of personalised medicine by allowing patients access to on-demand, customisable therapeutics. Robots are also being explored for treatment, by empowering precision surgery, rehabilitation, or targeted drug delivery. Within medical logistics, drones are being leveraged to deliver critical treatments to remote areas, collect samples, and even provide emergency aid. To enable seamless integration within healthcare, the Internet of Things technology is being exploited to form closed-loop systems that remotely communicate with one another. This review outlines the most promising healthcare technologies and devices, their strengths, drawbacks, and opportunities for clinical adoption.

Ingestible devices for studying the gastrointestinal physiology and their application in oral biopharmaceutics

Ingestible sensor systems are unique tools for obtaining physiological data from an undisturbed gastrointestinal tract. Since their dimensions correspond to monolithic oral dosage forms, such as enteric coated tablets or hydrogel matrix tablets, they also allow insights into the physiological conditions experienced by non-disintegrating dosage forms on their way through the gastrointestinal tract. In this work, the different ingestible sensor systems which can be used for this purpose are described and their potential applications as well as difficulties and pitfalls with respect to their use are presented. It is also highlighted how the data on transit times, pH, temperature and pressure as well as the data from different animal models commonly used in drug product development such as dogs and pigs have contributed to a deeper mechanistic understanding of oral drug delivery.

Ingestible Sensors and Sensing Systems for Minimally Invasive Diagnosis and Monitoring: The Next Frontier in Minimally Invasive Screening

Ingestible electronic systems that are capable of embedded sensing, particularly within the gastrointestinal (GI) tract and its accessory organs, have the potential to screen for diseases that are difficult if not impossible to detect at an early stage using other means. Furthermore, these devices have the potential to (1) reduce labor and facility costs for a variety of procedures, (2) promote research for discovering new biomarker targets for associated pathologies, (3) promote the development of autonomous or semiautonomous diagnostic aids for consumers, and (4) provide a foundation for epithelially targeted therapeutic interventions. These technological advances have the potential to make disease surveillance and treatment far more effective for a variety of conditions, allowing patients to lead longer and more productive lives. This review will examine the conventional techniques, as well as ingestible sensors and sensing systems that are currently under development for use in disease screening and diagnosis for GI disorders. Design considerations, fabrication, and applications will be discussed.

Trajectory assessment is useful when day-to-day esophageal acid exposure varies in prolonged wireless pH monitoring

Acid exposure time commonly varies from day-to-day in prolonged wireless pH monitoring. Thus, diagnosis based on the number of days with abnormal acid burden may be misleading or inconclusive. We hypothesize that assessing longitudinal patterns of acid exposure may be diagnostically useful. Therefore, this study aims to describe acid exposure trajectories and evaluate agreement between identified trajectory patterns and conventional grouping. In this retrospective cohort study, we assessed patients with nonresponse to proton pump inhibitor therapy who underwent wireless pH monitoring (≥72 h) off therapy between August 2010 and September 2016. The primary outcome was esophageal acid exposure time. Subjects were grouped as 0, 1, 2, and 3+ days positive based on number of days with an acid exposure time >5.0%. Latent class group-based mixture model identified distinct longitudinal acid exposure trajectory groups. Of 212 subjects included 44%, 18%, 14%, and 24% had 0, 1, 2, 3+ days positive, respectively. Group-based modeling identified three significantly stable acid exposure trajectories: low (64%), middle (28%), and high (8%). Trajectory grouping and days positive grouping agreed substantially (weighted K 0.69; 95% CI: 0.63-0.76). Trajectory grouping identified 62% of subjects with conventionally inconclusive studies (one or two days positive) into the low trajectory. Agreement between trajectory groups when using three versus four days of monitoring was substantial (K 0.70; CI: 0.61-0.78). In summary, we found that patients with nonresponse to proton pump inhibitors follow three acid exposure trajectories over prolonged pH-monitoring periods: low, middle, and high. Compared to conventional day positive grouping, the trajectory modeling identified the majority of inconclusive days positive into the low trajectory group. Analyzing prolonged wireless pH data according to trajectories may be a complimentary method to conventional grouping, and may increase precision and accuracy in identifying acid burden.

Two years' experience of using the Bravo wireless oesophageal pH monitoring system at a single UK tertiary centre

AIM

The Bravo wireless pH monitoring system enables oesophageal pH to be monitored in children intolerant to nasal catheters and records measurements over 48 hours. This study aimed to document the minimum child weight that enabled successful capsule placement and any associated complications. We also compared the diagnostic sensitivity of 48 hours versus 24 hours.

METHODS

We included 203 consecutive patients (122 male children) with clinically documented or suspected reflux symptoms. The age range was two years to 19 years, and the minimum weight was 9.29 kg. The pH capsule was deployed endoscopically under general anaesthetic. Recordings taken over 24 and 48 hours were compared to determine the frequency of differences and correlations in the reflux index and DeMeester scores.

RESULTS

Testing using the detached probe was successful in 190 children (93.6%) with weight as low as 9.29 kg, with no side effects, with failed deployment being the most frequent problem. Clinically different results in the reflux index were found in 16% of the children's day 1 or day 2 readings (p < 0.0001), suggesting the benefit of 48-hour measurements.

CONCLUSION

Measuring oesophageal pH with the Bravo wireless pH monitoring system was successful in 93.6% of cases. A 48-hour test improved the detection rate of gastro-oesophageal reflux disease by 16%.

Evaluation of Gastroesophageal Reflux Disease Using the Bravo Capsule pH System

Gastroesophageal reflux disease (GERD) is a disease predominantly seen in the West but there is a rising trend in Asia. Ambulatory 24-hour catheter-based pH monitoring has been the de facto gold standard test for GERD that correlates symptoms with acid reflux episodes. However, drawbacks such as patients’ discomfort, and catheter displacement render the test as cumbersome and error-prone. The Bravo pH wireless system is designed to be user-friendly and has an added advantage of prolonged pH monitoring. The system is comparable to the catheter-based pH monitoring system in terms of diagnostic yield and symptom-reflux association. Indications include evaluation of patients with refractory GERD symptoms and prior to anti-reflux surgery. Bravo utilizes a wireless pH-sensing capsule with a complete prepackaged system, and a data processing software. The capsule may be positioned indirectly using endoscopic or manometric landmarks or under direct endoscopic guidance. Optimal threshold cut-off values are yet to be standardized but based on available studies, for the Asian population, it may be recommended for total % time pH < 4 of 5.8 over 48 hours. Cost is a limitation but capsule placement is relatively safe although technical failures may be seen in small percentage of cases.

NERD: an umbrella term including heterogeneous subpopulations

Nonerosive reflux disease (NERD) represents the more common phenotypic presentation of GERD and comprises patients who have typical symptoms without any mucosal breaks at endoscopy. However, these patients are markedly heterogeneous from a pathophysiological point of view and should be correctly classified by means of 24 h impedance-pH testing, which enables detection of both acidic and weakly acidic reflux and correlation with symptoms. This technique is able to identify two subsets of NERD (that is, patients with an excess of acid or with a hypersensitive oesophagus to both acid and weakly acidic reflux) and patients with functional heartburn (who do not have any kind of reflux underlying their symptoms and must be excluded from the realm of GERD). The mechanisms of symptom generation are not clear in patients with NERD, but the presence of microscopic oesophagitis, including the dilation of intercellular spaces, seems to have a relevant role. Patients with NERD in whom acid is the main pathogenetic factor respond successfully to PPI therapy, while those with hypersensitive oesophagus to weakly acidic reflux need to be treated with reflux inhibitors or surgery, although the experience in this field is very scant. Patients with functional heartburn should undergo therapy with pain modulators, but large placebo-controlled trials are necessary.

A prospective multicenter registry of patients with chronic gastroesophageal reflux disease receiving transoral incisionless fundoplication

BACKGROUND

This study was undertaken to validate previously reported safety and symptomatic outcomes of transoral incisionless fundoplication (TIF), evaluate the relative benefit of TIF within different gastroesophageal reflux disease (GERD) subgroups, and to determine predictors of success in community settings.

STUDY DESIGN

Between January 2010 and February 2011, 100 consecutive patients who underwent TIF procedures at 10 centers were enrolled in this prospective, open-label, multicenter, single-arm study. Symptom improvement and objective outcomes of TIF were analyzed at 6-month follow-up.

RESULTS

One hundred TIF procedures were performed. No complications were reported. Median GERD symptom duration was 9 years (range 1 to 35 years) and median duration of proton pump inhibitor (PPI) use was 7 years (1 to 20 years). Maximal medical therapy resulted in incomplete symptom control for 92% of patients; GERD Health-Related Quality of Life (GERD-HRQL) total score was normalized in 73%. Median heartburn and regurgitation scores improved significantly, from 18 (range 0 to 30) and 15 (range 0 to 30) on PPIs before TIF to 3 (range 0 to 25) and 0 (range 0 to 25), respectively; p < 0.001. Median Reflux Symptom Index scores were reduced after TIF from 24 (range 14 to 41) to 7 (range 0 to 44); p < 0.001. Eighty percent of patients were completely off PPIs after TIF vs 92% of patients on PPIs before TIF. Preoperative factors associated with clinical outcomes were less severe heartburn (total GERD-HRQL ≤ 30, p = 0.02) and the presence of esophagitis (p < 0.02).

CONCLUSIONS

Transoral incisionless fundoplication is safe and effective in multiple community-based settings in the treatment of medically refractory GERD, as demonstrated by an absence of complications, excellent symptom relief, and complete cessation of PPIs at 6-month follow-up.

24 Versus 48-hour bravo pH monitoring

BACKGROUND

Historical ambulatory pH monitoring systems for the evaluation of gastroesophageal reflux disease have been catheter based and uncomfortable for patients, commonly limiting both their diet and activities. Catheter-based studies have also been reported to underestimate the amount of reflux a patient may have in a normal, routine day. Compared with conventional catheter-based pH monitoring systems, wireless (Bravo) pH monitoring is better tolerated by patients and allows for an increased duration of pH recording. Currently, there is lack of data regarding the optimal duration of wireless studies and concern that day 1 results are not typical of a patient's routine lifestyle, given the effects of sedation. Few studies have evaluated the merits of 24 versus 48-hour wireless pH monitoring.

AIMS

The aims of this study were (1) to identify differences in reflux parameters between 24 versus 48-hour testing as measured by wireless pH monitoring and (2) to assess the effect of 48-hour studies on the number of reflux episodes and symptom correlation as compared with 24-hour studies.

METHODS

A retrospective chart review of 124 consecutive patients who underwent 48-hour wireless esophageal pH monitoring studies was prepared. All patients underwent esophagogastroduodenoscopy using intravenous conscious sedation before wireless capsule placement. Acid reflux variables (including total reflux time, number of reflux episodes, and total percent time of pH<4) and symptom-association probability (SAP) scores were compared for day 1 versus day 2 versus total.

RESULTS

Forty-eight-hour SAP scores were significantly higher when compared with the first 24 hours for all reported primary symptoms. SAP scores were calculated at 24 and 48 hours, respectively for heartburn (56 vs. 65, P<0.0001), regurgitation (65 vs. 80, P<0.0001), chest pain (59 vs. 78, P=0.0009), and cough (55 vs. 64, P=0.0027). In addition, the percentage of SAP scores >95 was significantly higher for both heartburn and regurgitation (34% vs. 48%, P=0.003 and 38% vs. 62%, P=0.005). As expected, 48-hour testing also captured a significantly higher number of reflux episodes as compared with day 1 results alone (97 vs. 47, P<0.0001). There were no statistical differences noted between the 2 days for total percent time of pH <4.

CONCLUSIONS

Forty-eight-hour wireless (Bravo) pH monitoring strengthens symptom correlation as compared with 24-hour results alone and yields a greater percentage of SAP scores >95 for typical symptoms of gastroesophageal reflux disease. Prolonged recording of patient symptoms and/or sedation effects may account for the better symptom correlation. Although there were no statistical differences seen in this study between 24 and 48-hour studies for total percent time pH <4, 48-hour studies captured significantly more reflux episodes as compared with 24 hours of monitoring alone. These results suggest that patients undergoing wireless pH monitoring should have 48-hour studies performed as a standard of practice.

Esophageal pH monitoring with the BRAVO capsule: experience in a single tertiary medical center

AIM

The aim of the present study was to report the global experience with placement, complication rate, and recording of esophageal pH using the BRAVO capsule at our institution.

PATIENTS AND METHODS

We recorded the rate of any technical problems and complications during placement in all of the patients (ages 4-22 years) who received this device during a 2-year period. All of the patients undergoing esophagogastroduodenoscopy with the placement of BRAVO pH capsule were included in this analysis. We also examined the pH data recorded on days 1 and 2 for significant day-to-day variability during 2 days of pH monitoring.

RESULTS

Two hundred eighty-nine BRAVO pH probes were placed from January 1, 2006 to December 31, 2008. At least 1 day of data was obtained in 278 patients (96.2%). Two days of data were obtained in 274 patients (94.8%). Of all of the reported complications, 1% occurred before deployment of the capsule, 4% occurred during deployment of the capsule, and 9% occurred after successful deployment of the capsule. One patient experienced a superficial esophageal tear that was associated with failure of the capsule to release from the delivery system. No patient requested removal of the capsule and all of the capsules detached within 14 days. In 9.12% of our patients, reflux index was normal on day 1 and abnormal on day 2. There was no statistically significant difference between reflux index recorded on day 1 versus day 2 (P = 0.686).

CONCLUSIONS

The BRAVO pH capsule is easy to place, safe, and well tolerated by children. Performing a 48-hour study detected abnormal reflux in an additional 9% of our patients.

Clinical and pH-metric outcomes of transoral esophagogastric fundoplication for the treatment of gastroesophageal reflux disease

BACKGROUND

Transoral treatment of gastroesophageal reflux disease (GERD) using the EsophyX device enables creation of an esophagogastric fundoplication with potential for better control of reflux than gastrogastric techniques. Efficacy and safety of a rotational/longitudinal esophagogastric transoral incisionless fundoplication (TIF) was evaluated retrospectively using subjective and objective outcomes.

METHODS

Thirty-seven consecutive patients on antisecretory medication and with proven gastroesophageal reflux and limited hiatal hernia underwent TIF for persistent GERD symptoms. Five patients were reoperations for failed laparoscopic fundoplication.

RESULTS

Of the 37 treated patients, 57% were female. The median age was 58 (range=20-81) years and BMI was 25.5 (range=15.9-36.1) kg/m2. Sixty-eight percent indicated GERD-associated cough, asthma, or aspiration as a primary complaint and 32% complained of heartburn or regurgitation. The TIF procedures created tight wraps of 230°-330° extending 3-4 cm above the Z-line. Two complications occurred: one mediastinal abscess treated laparoscopically and one postoperative bleeding requiring transfusion. At 6 (range=3-14) months median follow-up TIF resulted in a significant improvement of both atypical and typical symptoms in 64% and 70-80% of patients, respectively, as indicated by the corresponding GERD health-related quality of life (HRQL) and reflux symptom index (RSI) score reduction by 50% or more compared to baseline on proton pump inhibitors (PPIs). No patient reported problems with dysphagia, bloating, or excess flatulence, and 82% were not taking any PPIs. Reflux characteristics were significantly improved and normalized in 61, 89, and 56% of patients in terms of acid exposure, number of refluxates, and DeMeester scores, respectively. TIF was effective in treating GERD in 75% of patients among whom 54% were in a complete "remission" and 21% were "improved." The remaining 25% were considered failures, and five (13.5%) patients underwent revision.

CONCLUSION

Rotational/longitudinal esophagogastric fundoplication using the EsophyX device significantly improved symptomatic and objective outcomes in over 70% of patients at median 6-month follow-up. Post-fundoplication side effects were not reported after TIF.

Do we really understand the role of the oesophagogastric junction in disease?

The role of the oesophago-gastric junction (OGJ) in gastro-oesophageal reflux disease is still not completely understood, and there is no clinically used method to assess the OGJ function in patients. Only indirect methods such as pH studies are carried out. The OGJ acts a valve controlling the flow of solids, liquids and gases between the oesophagus and the stomach. Manometry can determine if a sphincter is toned or relaxed; but, it cannot confirm that the sphincter region is actually open. Distension is a new technique for measuring function in the OGJ. By measuring the cross-sectional area through the narrow region in the junction during distension of a catheter mounted bag, much more information on the opening and closing patterns of the junction can be determined. This technique has already been demonstrated to show changes in the OGJ after surgical treatments for reflux disease. New measurement ideas around the concept of distending the OGJ offer new hope that a clinically useable test for compliance at the junction can be developed and could potentially help in determining appropriate therapy.