Multichannel Intraluminal impedance-pH Research Articles

Efficacy of Vonoprazan, a Novel Potassium-Competitive Acid Blocker, in Patients with Proton Pump Inhibitor-Refractory Acid Reflux

Background/Aim: We evaluated the efficacy of vonoprazan (VPZ), a novel potassium-competitive acid blocker, in patients with proton pump inhibitor (PPI)-refractory gastroesophageal reflux disease (GERD), exhibiting continued pathological esophageal acid exposure (EAE). Methods: Despite ≥8 weeks of appropriate PPI therapy, patients with ­persistent reflux symptoms and pathological EAE times (EAETs ≥4%) were invited to switch to VPZ treatment. After an 8-week-course of once-daily VPZ (20 mg), multichannel intraluminal impedance-pH (MII-pH) monitoring was repeated to compare gastric acid exposure times (GAETs), EAETs, and other reflux parameters relative to the baseline values. Before each MII-pH study, reflux symptom severities were scored using the Gastrointestinal Symptom Rating Scale; erosive esophagitis and fasting plasma gastrin levels were also assessed. Results: From among the 124 patients undergoing MII-pH monitoring, 13 patients (median age, 69 years; females, 64%) were monitored at baseline (while on PPI therapy) and after VPZ therapy. The median GAET associated with VPZ treatment (23.8%) was less than that for PPI treatment (41.1%; p = 0.01), including both daytime and nighttime measurements. VPZ therapy resulted in better median EAET values (4.5%) than did PPI therapy (10.6%) during the 24-h monitoring period (p = 0.055). EAE normalization was achieved in 46% of VPZ-treated patients and was associated with complete gastric acid suppression (p = 0.005). After switching to VPZ, reflux symptoms (p < 0.01) and erosive esophagitis (p = 0.01) improved. Conclusion: In patients with PPI-refractory GERD, VPZ provides more potent gastric acid suppression, more effective EAE control, enhanced symptom improvement, and better esophagitis healing than PPIs.

Use of Point-of-Care Gastric pH Testing to Assess the Efficacy of Acid Suppression Therapy in the Neonatal Intensive Care Unit.

The use of acid suppression therapies in newborns lacks efficacy and is associated with adverse effects. Point-of-care (POC) assessment of gastric aspirate pH may provide an objective, noninvasive measure of gastric acidity in tube fed infants. We conducted the present study to characterize the POC gastric pH levels in gastric tube fed infants before and after initiation of enteral omeprazole or ranitidine. Retrospective cohort study of infants with gastric aspirate pH levels determined by POC pH strips. Gastric pH levels recorded during 7 days before and 14 days after medication initiation were compared using Wilcoxon's sign-rank tests. Among 307 evaluated infants, 284 (92%) had a median gastric pH level ≥4 in 7 days prior to ranitidine or omeprazole. In 14 days after medication initiation, the median gastric pH of infants with pretreatment median gastric pH < 4 increased to 4.5 and 5 (p < 0.01) in the ranitidine and omeprazole groups, respectively. There was no change in infants with pretreatment median gastric pH ≥4. Among infants receiving gastric tube feedings and enteral omeprazole or ranitidine, only those with a pretreatment gastric pH level <4 demonstrated a significant increase in gastric pH. Validation of our findings against esophageal pH multichannel intraluminal impedance testing is needed.

Evaluation and Management of Laryngopharyngeal Reflux Disease: State of the Art Review.

To review the current literature about the epidemiology, clinical presentation, diagnosis, and treatment of laryngopharyngeal reflux (LPR). PubMed, Cochrane Library, and Scopus. A comprehensive review of the literature on LPR epidemiology, clinical presentation, diagnosis, and treatment was conducted. Using the PRISMA statement, 3 authors selected relevant publications to provide a critical analysis of the literature. The important heterogeneity across studies in LPR diagnosis continues to make it difficult to summarize a single body of thought. Controversies persist concerning epidemiology, clinical presentation, diagnosis, and treatment. No recent epidemiologic study exists regarding prevalence and incidence with the use of objective diagnostic tools. There is no survey that evaluates the prevalence of symptoms and signs on a large number of patients with confirmed LPR. Regarding diagnosis, an increasing number of authors used multichannel intraluminal impedance-pH monitoring, although there is no consensus regarding standardization of the diagnostic criteria. The efficiency of proton pump inhibitor (PPI) therapy remains poorly demonstrated and misevaluated by incomplete clinical tools that do not take into consideration many symptoms and extralaryngeal findings. Despite the recent advances in knowledge about nonacid LPR, treatment protocols based on PPIs do not seem to have evolved. The development of multichannel intraluminal impedance-pH monitoring and pepsin and bile salt detection should be considered for the establishment of a multiparameter diagnostic approach. LPR treatment should evolve to a more personalized regimen, including diet, PPIs, alginate, and magaldrate according to individual patient characteristics. Multicenter international studies with a standardized protocol could improve scientific knowledge about LPR.

Evaluation of Noncardiac Chest Pain (NCCP) in Iranian Patients with Nonerosive Reflux Disease (NERD) based on 24-Hour Multichannel Intraluminal Impedance-pH (MII-PH) Monitoring Tests

Background/Aims: The noncardiac chest pain (NCCP) remains a challenge in diagnosis and management. This symptom has a different etiology but suggests that gastroesophageal disease is the most common of NCCP. Method: This study was conducted on 715 participants aged 11 to 63 years, with the chief complaint of regurgitation and NCCP. The esophageal manometry and multichannel intraluminal impedance-pH (MIIPH) monitoring tests were performed based on off proton pump inhibitors therapy in all patients. Results: The NCCP was more prevalent in males (61.5%) than in females (38.5%) and more prevalent in patients younger than 50 years (69.1%). The mean DeMeester score value was higher in NCCP group (45.5±10.8). Of the patients with NCCP, 41.4% showed a pathological esophageal acid exposure time (EAET). Moreover, acid (24.7%), gas (45.8%) and mixed reflux episodes (55.6%) were more prevalent in patients with NCCP in supine position than those with regurgitation. Conclusions: The present study revealed that acid, gas, and mixed reflux episodes were more prevalent in patients with noncardiac chest pain (NCCP) than those with regurgitation, mostly in supine position, however, the differences were not significant between the 2 groups (p>0.05). Furthermore, NCCP was more prevalent in males and patients younger than 50 years.

High-resolution Manometry Findings During Solid Swallows Correlate With Delayed Reflux Clearance and Acid Exposure Time in Non-erosive Reflux Disease Patients.

Background/AimsThe role of esophageal motility in determining gastroesophageal reflux disease (GERD) severity has not been completely evaluated. A few studies have investigated high-resolution manometry (HRM) patterns during solid swallows. The present study evaluates the HRM patterns of non-erosive reflux disease (NERD) patients during both liquid and solid swallows and their correlation with the severity of GERD.MethodsIn 23 NERD patients and 15 healthy volunteers (HVs) HRM was performed during a standard solid meal in a seated position, followed by 24-hour impedance-pH monitoring.ResultsOf the 31 patients, 10 showed a pathological acid exposure time (AET; NERD patients), 13 a normal pH profile with positive symptom association probability (SAP; reflux hypersensitivity patients), and 8 normal AET and SAP (functional heartburn patients). Mean distal contractile integral and distal latency values, in all patient groups and HVs, were significantly higher during solid swallows. In the group of 10 NERD patients, the number of large breaks of the esophageal peristalsis was 16 out of 100 liquid swallows (16%) and 31 out of 171 solid swallows (18%). Fourteen out of 100 liquid swallows (14%) and 25 out of 171 solid swallows (15%) resulted ineffective. Mean reflux clearing time at multichannel intraluminal impedance-pH was 17.6 ± 3.7 seconds. NERD patients presented, during solid swallows, a significantly higher proportion of large peristaltic breaks and of ineffective swallows than reflux hypersensitivity and functional heartburn patients.ConclusionHRM during solid swallows reveals motor abnormalities, undetected during liquid swallows, which might be involved in delaying reflux and acid clearance in patients with GERD.

Erythromycin and Reflux Events in Premature Neonates: A Randomized Clinical Trial.

Gastroesophageal reflux disease (GERD) in premature neonates may manifest as apnea, bradycardia, growth failure, aspiration, or feeding intolerance. Erythromycin ethylsuccinate (EES), is often used as a pro-kinetic in the management of GERD, despite lack of evidence or safety from randomized controlled trials. We sought to study the efficacy of enteral EES at a dose of 50 mg · kg · day in decreasing the frequency of gastroesophageal reflux events as determined by pH-multichannel intraluminal impedance (pH-MII) monitoring. In a randomized, double-blind, placebo-controlled trial, eligible premature neonates with clinical signs of GERD underwent 24-hour pH-MII monitoring. If >5 reflux events were identified on pH-MII, then subjects were randomized to receive either EES or placebo. Repeat 24-hour pH-MII was performed on day 7 of study treatment and compared to initial pH-MII. Forty-three premature neonates were enrolled. Of those, 31 neonates were randomized, 15 to EES and 16 to placebo with a median (IQR) pretreatment total reflux events per 24 hours of 23 (16-40) and 29 (12-40), respectively. Day 7 total events per 24 hours decreased by 4 events in the EES group to 19 (15-33) and by 10 events in the placebo group to 19 (11-26) (P = 0.09). There were no differences in pretreatment and day 7 acidic and nonacidic reflux, proximal reflux, total or percent reflux time, median or longest bolus clearance time, or nurse-reported apnea events between groups. Enteral EES did not decrease reflux events on 24-hour pH-MII at the dose studied. Therefore, it may be ineffective in the treatment of GERD in premature neonates.

Evaluating the yield of gastrointestinal testing in pediatric patients in aerodigestive clinic.

To improve understanding of the interrelatedness of airway and esophageal diagnoses by evaluating the yield of procedural and radiographic testing of the gastrointestinal tract in children with airway conditions by their referring diagnoses in a pediatric aerodigestive clinic. A retrospective chart review of all 325 patients seen in the aerodigestive program from 2010 to 2013 was performed in a single academic medical center. Demographics and results from esophagogastroduodenoscopies with biopsies (EGD), upper gastrointestinal fluoroscopy studies (UGI), and pH multichannel intraluminal impedance probe (pH-MII) performed within 30 days of the clinic visit were evaluated according to presenting diagnoses. Mean patient age was 3.15 years (range 0.15-24 years) and 41.2% were born premature. 189/325 (58.1%) were on acid suppression. A total of 295 EGD, 193 pH-MII, and 54 UGI were performed. The most common diagnosis with an abnormal pH-MII was asthma. The most common diagnoses with an abnormal EGD were feeding difficulty and tracheal esophageal fistula/ esophageal atresia (TEF/EA). EGDs were normal in 188/295 (63.7%), while 39/295 (13.2%) demonstrated esophagitis, and 22/295 (7.5%) had >15 esophageal eosinophils per high power field. The majority of pH-MII (144/193 [74.6%]) and UGI (47/54 [87%]) were normal. Children with feeding difficulty, TEF/EA, and asthma were the mostly likely to have a histologic abnormality on EGD or an abnormal pH-MII. The majority of children were previously prescribed acid suppression medication and had a referring diagnosis of gastroesophageal reflux disease but were subsequently found to have normal evaluation. Prospective studies are needed to optimize care of this population.

Wireless 24, 48, and 96Hour or Impedance or Oropharyngeal Prolonged pH Monitoring: Which Test, When, and Why for GERD?

pH monitoring technologies are routinely utilized in practice to further evaluate symptoms of gastro-esophageal reflux disease and laryngopharyngeal reflux (LPR). This is a review of the recent literature of the available pH monitoring technology and creates an algorithm in the diagnostic work up of a patient with GERD or LPR. The catheter-free wireless pH monitor traditionally collects data for 48h. Recent studies have found that extending to 96h can be helpful in patients with conflicting results on the first 2days of the study. In addition, 96h can allow for testing both on and off of PPI therapy. The oropharyngeal monitoring device is a newer technology that is designed to aid in the diagnoses of LPR. There are limitations with this technology as there is no universal abnormal cutoff and some studies have suggested a poor correlation between multichannel intraluminal impedance-pH (MII-pH) and the oropharyngeal monitoring device. MII-pH has recently developed two additional parameters, the measurement of three 10-min nighttime periods and the post-reflux swallow-induced peristaltic wave (PSPW) index, both of which may increase accuracy of testing. Each of these technologies can provide unique data regarding acid reflux exposure in the esophagus and oropharynx. The wireless pH monitor performed off of PPI therapy can help to establish or exclude the diagnosis of GERD. For those patients with refractory symptoms on PPI, MII-pH study can be performed while on therapy and provides data regarding the response to treatment. Oropharyngeal pH monitoring is being utilized in some practices to aid in diagnosis of LPR, but the scientific validity is controversial.

Convenient Method of Measuring Baseline Impedance for Distinguishing Patients with Functional Heartburn from those with Proton Pump Inhibitor-Resistant Endoscopic Negative Reflux Disease

Background: Combined 24-h intraesophageal pH-multichannel intraluminal impedance (24MII-pH) used for assessing gastroesophageal reflux disease by measuring baseline impedance (BI) requires a 24-h measuring period. In the present study, we developed a quick method of measuring BI and evaluated its usefulness in classifying patients with proton pump inhibitor (PPI)-refractory non-erosive reflux diseases (NERD) as having functional heartburn (FH) or endoscopic-negative reflux disease (ENRD). Methods: Ninety-one NERD patients without esophageal motility disorder underwent 24MII-pH monitoring while on a PPI. The measurements of the mean nocturnal BI (MNBI) and short MNBI were assessed at 3 times (at about 1: 00, 2: 00, and 3: 00 am) for 10 min and 30 s respectively. The measurement of the simple mean BI (MBI) was performed once 30 s at about 11: 00 am. Results: Ninety-one patients were divided into 2 groups: 59 with ENRD and 32 with FH. The cutoff, specificity, and sensitivity for distinguishing patients with FH were as follows: MNBI, 2,874.1 Ω, 72%, and 72%; short MNBI, 2,857.6 Ω, 74%, and 84%; and simple MBI, 2,874.1 Ω, 86%, and 78% respectively. Conclusion: Measuring the simple MBI is a quick method and is useful for distinguishing patients with FH from those in a cohort with PPI-refractory NERD.

Developing a diagnostic understanding of GERD phenotypes through the analysis of levels of mucosal injury, immune activation, and psychological comorbidity.

SummaryPatients with gastroesophageal reflux disease (GERD) can present with typical or atypical symptoms. The aim of this study is to explore the underlying physiological and psychological mechanisms that lead to different symptomatic manifestations of GERD. A total of 238 patients diagnosed with GERD underwent gastroscopy, 24 h multichannel intraluminal impedance-pH (MII-pH) monitoring, and psychological assessment with questionnaires. Patient symptoms were used to classify GERD into phenotypes of typical reflux syndrome (TRS, n = 87), reflux chest pain syndrome (RCS, n = 98), and extraesophageal syndromes (EES, n = 53). 38 healthy volunteers served as controls. Reflux parameters and baseline impedance values (BIVs) were acquired from MII-pH monitoring results. A subset of subjects were biopsied from the lower esophagus; certain immune cells were stained with immunohistochemistry. BIVs in GERD patients (TRS, RCS, and EES) were significantly lower than in healthy controls and TRS patients exhibited the lowest BIVs (all P < 0.01). This indicated that the extent of mucosal injury differed across groups. TRS patients had higher acid exposure time (AET) compared to RCS, EES and controls (all P < 0.05). RCS patients had more intraepithelial T lymphocyte (IEL) and mast cell (MC) infiltration, and higher psychometric scores compared to TRS patients and controls (all P < 0.05), suggesting a possible stress-related esophageal hypersensitivity basis. TRS patients are characterized by acid reflux and correlated mucosal injury, which explains their typical reflux symptoms. RCS patients exhibit less acid-related injury but possible psychological stress-related esophageal hypersensitivity, which could be the main cause of their esophageal pain.

The Role of Reflux in Childhood Otorhinolaryngological Disorders

This article seeks to review the current literature on the role of laryngopharyngeal reflux in the development of various disorders of the ear, nose and throat in infants and children including otitis media, chronic rhinosinusitis and airway disorders. The aim is to guide the otolaryngology clinician in investigation and management of reflux and to identify priorities for future research in this area. Many otolaryngological disorders coexist with reflux more often than might be expected by chance, but evidence of causality is weak. Although many otolaryngologists are convinced that treatment of reflux can make a significant difference to the clinical course of many upper airway disorders, the evidence to support this is lacking. In part, this is due to inadequate tools for describing the symptoms and endoscopic signs of laryngopharyngeal reflux and the lack of a sensitive, specific and reliable objective test. Further research demonstrating simple associations between otolaryngological diseases and reflux is unlikely to be of much value. Instead, researchers should concentrate their efforts on studies to develop and validate better means of recording symptoms and signs of laryngopharyngeal reflux and investigating the clinical utility of salivary pepsin, oropharyngeal pH monitoring and multichannel intraluminal impedance.

Evaluation of Esophageal Mucosal Integrity in Patients with Gastroesophageal Reflux Disease

Background: Impaired esophageal mucosal integrity plays a role in causing symptoms of gastroesophageal reflux disease (GERD). Recently, the assessment of esophageal baseline impedance (BI) using the multichannel intraluminal impedance-pH (MII-pH) test was suggested as a surrogate technique for the study of esophageal mucosal integrity and was reported to be useful in distinguishing GERD from non-GERD. However, measuring BI requires a 24-h testing period, is complicated, and causes considerable patient discomfort. Summary: Recently, endoscopy-guided catheters that can measure mucosal impedance (MI) and mucosal admittance (MA), which is the inverse of impedance, were developed, and their usefulness in measuring MI and MA for the diagnosis of GERD has been reported. In these studies, esophageal MI values were significantly lower in patients with GERD than in those without GERD. In contrast, esophageal MA was significantly higher in patients with GERD than in those without. Furthermore, we reported that MA is inversely correlated with BI and correlated with acid exposure time. Key Messages: Endoscopy-guided real-time measurement of MI and MA may allow the estimation of mucosal integrity and may be a useful diagnostic tool for patients with GERD in a manner similar to 24-h MII-pH monitoring.

Reflux Patterns Characteristics of Iranian Patients with Nonerosive Reflux Disease (NERD) Based on 24-Hour Multichannel Intraluminal Impedance-pH (MII-pH) Monitoring Tests

Reflux Patterns Characteristics of Iranian Patients with Nonerosive Reflux Disease (NERD) Based on 24-Hour Multichannel Intraluminal Impedance-pH (MII-pH) Monitoring Tests

Dysphagia survey using 24-Hour multichannel intraluminal impedance-pH (MII-PH) monitoring tests in patients with nonerosive reflux disease (NERD): A case-Control study

Dysphagia survey using 24-Hour multichannel intraluminal impedance-pH (MII-PH) monitoring tests in patients with nonerosive reflux disease (NERD): A case-Control study

Indications of 24-h esophageal pH monitoring, capsule pH monitoring, combined pH monitoring with multichannel impedance, esophageal manometry, radiology and scintigraphy in gastroesophageal reflux disease?

Ambulatory esophageal pH monitoring is an essential method in patients exhibiting signs of non-erosive reflux disease (NERD) to make an objective diagnosis. Intra-esophageal pH monitoring is important in patients who are non-responsive to medications and in those with extraesophageal symptoms, particularly in NERD, before surgical interventions. With the help of the wireless capsule pH monitoring, measurements can be made under more physiological conditions as well as longer recordings can be performed because the investigation can be better tolerated by patients. Ambulatory esophageal pH monitoring can be detected within normal limits in 17%-31.4% of the patients with endoscopic esophagitis; therefore, normal pH monitoring cannot exclude the diagnosis of gastroesophageal reflux disease (GERD). Multi-channel intraluminal impedance pH (MII-pH) technology have been developed and currently the most sensitive tool to evaluate patients with both typical and atypical reflux symptoms. The sensitivity of a pH catheter test is 58% for the detection of acid reflux compared with MII-pH monitoring; further, its sensitivity is 28% for the detection of weak acid reflux compared with MII-pH monitoring. By adding impedance to pH catheter in patients with reflux symptoms, particularly in those receiving PPIs, it has been demonstrated that higher rates of diagnoses and symptom analyses can be obtained than those using only pH catheter. Esophageal manometry is used in the evaluation of patients with functional dysphagia and unexplained noncardiac chest pain and prior to antireflux surgery. The use of esophageal manometry is suitable for the detection of esophageal motor patterns and extreme motor abnormalities (e.g., achalasia and extreme hypomotility). Esophageal manometry and ambulatory pH monitoring are often used in assessments prior to laparoscopic antireflux surgery and in patients with reflux symptoms refractory to medical treatment. Although the esophageal motility is predominantly normal in patients with non-acid reflux, ineffective esophageal motility is often monitored in patients with acid reflux. In the literature, there are contradictory and an insufficient number of studies regarding radiological methods for the diagnosis of GERD. There are inconsistent values for sensitivity and specificity among the barium studies. There are inadequate studies in the literature involving scintigraphic examinations in the diagnosis of GERD, and a majority of existing studies have been conducted in the pediatric group. The results of a few studies do not provide sufficient contribution toward the implementation in clinical practice.

Association Between Pepsin in the Saliva and the Subjective Symptoms in Patients With Laryngopharyngeal Reflux

Our study was designed to further evaluate the relationships between the saliva pepsin level and the symptoms and quality of life of patients with laryngopharyngeal reflux (LPR). A prospective cohort study without controls. Tertiary teaching hospital. We analyzed 50 patients diagnosed with LPR by 24-hour multichannel intraluminal impedance pH monitoring. All subjects were instructed to collect saliva samples upon waking in the morning. The saliva pepsin levels were analyzed using enzyme-linked immunosorbent assay. The Reflux Symptom Index, Reflux Finding Score, Laryngopharyngeal Reflux-Health-Related Quality of Life, and Short Form 36 survey were administered. The pepsin was detected in the saliva of 41 patients with LPR (17.15 ± 20.42 ng/mL). Nine patients did not have pepsin in the saliva. There were no significant associations between the pepsin level in the saliva and Reflux Symptom Index, Laryngopharyngeal Reflux-Health-Related Quality of Life, or Short Form 36 of patients with LPR. The saliva pepsin level is not significantly correlated with LPR symptoms or quality of life in LPR patients. It may be true that there is no association between pepsin levels and LPR symptoms, but this lack of association does not prove the lack of pathophysiological effect.

Gastroesophageal flap valve reflected EGJ morphology and correlated to acid reflux

ObjectiveThe anatomy of esophagogastric junction (EGJ) serves as the anti-reflux barrier. The gastroesophageal flap valve (GEFV) is a component of EGJ. The aim of the current study was to assess its correlation with the esophageal acid exposure and the impact on anti-reflux barrier function by using the metrics of EGJ contraction.MethodsEighty three patients with typical GERD symptoms were included in the study. Upper endoscopy, high-resolution manometry (HRM) and 24 h multichannel intraluminal impedance-pH (MII-pH) monitoring were performed in all patients. GEFV was determined as four grades during endoscopic examination based on the Hill classification. The esophageal pressure topography (EPT) metrics defined in the updated Chicago Classification were measured by HRM, including integrated relaxation pressure (IRP), EGJ contractile index (EGJ-CI),expiratory EGJ pressure(EGJP-exp) and inspiratory EGJ pressure (EGJP-insp).ResultsThe GEFV grade III and IV was more commonly found in patients with esophagitits (p < 0.05). The acid exposure time (AET%) and supine AET% were lower in patients with GEFV grade I (p < 0.01). There was weak correlation between AET% and GEFV grades (r = 0.27, p = 0.013). There were more EGJ morphology type III in patients with GEFV grade IV (p < 0.05).There were no significant differences on the values of four HRM metrics among the patients with different GEFV grades (p > 0.05).ConclusionThe GEFV grades were associated with acid reflux positively and could be a good reflection of EGJ morphology in HRM. But it had no impact on the four HRM metrics. Our research revealed that GEFV may play an assistant role in the anti-reflux barrier.

Visual and Automated Computer Analysis Differ Substantially in Detection of Acidic Reflux in Multichannel Intraluminal Impedance–pH Monitoring

Visual and Automated Computer Analysis Differ Substantially in Detection of Acidic Reflux in Multichannel Intraluminal Impedance–pH Monitoring

Severe Delayed Gastric Emptying Induces Non-acid Reflux up to Proximal Esophagus in Neurologically Impaired Patients.

Background/AimsThe aim of this study is to investigate the degree of delayed gastric emptying (DGE) and evaluate how the severity of DGE affects gastroesophageal reflux disease (GERD) in neurologically impaired (NI) patients utilizing 24-hour multichannel intraluminal impedance pH measurements (pH/MII) and 13C-acetate breath test (13C-ABT) analyses.Methods13C-ABT and pH/MII were conducted in 26 NI patients who were referred to our institution due to suspected GERD. At first, correlation analyses were performed to investigate the correlation between the 13C-ABT parameters and the clinical or pH/MII parameters. Thereafter, all patients were divided into 2 groups (DGE and severe DGE [SDGE] group) according to each cut off half emptying time (t1/2, 90–170 minutes). Each pH/MII parameter was compared between the 2 groups in each set-up cutoff t1/2.ResultsThe mean t1/2 of all patients was 215.5 ± 237.2 minutes and the t1/2 of 24 (92.3%) patients were > 100 minutes. Significant moderate positive correlations were observed between both t1/2 and lag phase time and the non-acid reflux related parameters. Furthermore, the patients in the SDGE group demonstrated higher non-acid reflux related parameters than those of the DGE groups when the cutoff was t1/2 ≥ 140 minutes.ConclusionThe present study demonstrated that GE with t1/2 ≥ 140 minutes was related to an increase of non-acid exposure reaching up to the proximal esophagus in NI patients, and indicating that NI patients with SDGE might have a high risk of non-acid GERD.

Acid and nonacid gastroesophageal reflux after single anastomosis gastric bypass. An objective assessment using 24-hour multichannel intraluminal impedance-pH metry

BackgroundSingle anastomosis gastric bypass (SaGB) was introduced in 2001 as an alternative to “loop” gastric bypass. It was considered as a procedure that would eliminate alkaline reflux and associated esophagitis. ObjectivesExisting evidence about the postoperative incidence of gastroesophageal reflux (GERD) after SaGB is based on studies using symptom questionnaires. The aim of our study was to evaluate GERD 12 months after SaGB by using 24-hour multichannel intraluminal impedance pH metry (24-h MIIpH). SettingSurgical department of a university hospital MethodsMorbidly obese candidates for SaGB underwent 24-hour MIIpH prior and 12 months after their bariatric procedure. ResultsThere were 11 patients included in this prospective study. Results of 24-hour MIIpH revealed that DeMeester score (40.48 versus 24.16, P = .339) had an increasing trend 12 months after SaGB. Acid reflux episodes decreased, whereas nonacid reflux episodes increased postoperatively, both in proximal and distal esophagus. Total median bolus clearance time and acid clearance time increased. De novo GERD developed in 2 patients (28.6%) and worsening of already existing GERD developed in all patients with preoperative evidence of GERD. ConclusionThe use of symptom questionnaires to assess postoperative GERD after SaGB may not accurately depict the real image. Twenty-four–hour MIIpH in 12 months after SaGB revealed an increase of total number of nonacid reflux episodes and a decrease of total number of acid reflux episodes, with longer duration of each acid reflux episode. Close postoperative follow-up with reflux testing and possibly endoscopy could eliminate the risk of complicated GERD.