Relationship Between Resultant Force Vector Acting on Human Organs From Food Bolus and the Bolus Configuration During Swallowing Using Numerical Swallowing Simulation With Moving Particle Simulation Method.

This study investigates the forces exerted on organs during swallowing, specifically focusing on identifying forces other than those resulting from direct organ contact. Using a swallowing simulator based on the moving particle method, we simulated the swallowing process of healthy individuals upon the ingestion of thickened foods, which were simulated as shear-thinning flow without yield stress. We extracted the resultant force vectors acting on the organs and shape of the bolus at each time interval. The simulation results confirmed that the bolus originates from tongue movement and is transferred between the oral cavity and pharynx, with each organ's coordinated movements with the tongue occurring at their respective positions, as indicated by the balance of the resultant force vectors. Utilizing the information about the resultant force vectors obtained through simulations, we calculated the physical parameters of impulse, energy, and power. The variations in these physical parameters were aligned with the behaviors of both the biological system and the food bolus during swallowing. The force values calculated from the simulations closely approximate the theoretical values. Furthermore, the forces calculated from the simulations were relatively smaller than the force values derived from pressure information, such as that from high-resolution manometry and tongue pressure sensors. This difference can be attributed to the simulations extracting only the forces exerted on the organ by the food bolus. Force information on organs has the potential to provide a new interpretation of conventional mechanical indicators such as manometry and tongue pressure sensors.

Achalasia Cardia: A Case Series.

ABSTRACT: Achalasia cardia is a rare disorder that impacts the lower esophageal sphincter and esophageal body. Due to its wide range of symptoms, it can be difficult to diagnose. Here we report three cases of Achalasia Cardia during a period of 9 months. The first patient, an 18-year-old male, presented with dysphagia and was evaluated with barium swallow and high-resolution manometry (HRM) revealing Achalasia Cardia. In the second case, a 37-year-old female had a prolonged diagnostic journey due to multiple comorbidities before a barium swallow finally revealed achalasia cardia. The third patient, a 47-year-old female was promptly diagnosed with barium swallow. All the cases were successfully treated with laparoscopic Heller's myotomy with anterior Dor's fundoplication. This case series highlights the potential for delayed diagnosis and the importance of early recognition, tailored diagnostic approaches, and the efficacy of surgical management.

The pleural gradient does not reflect the superimposed pressure in patients with class III obesity.

BACKGROUND: The superimposed pressure is the primary determinant of the pleural pressure gradient. Obesity is associated with elevated end-expiratory esophageal pressure, regardless of lung disease severity, and the superimposed pressure might not be the only determinant of the pleural pressure gradient. The study aims to measure partitioned respiratory mechanics and superimposed pressure in a cohort of patients admitted to the ICU with and without class III obesity (BMI ≥ 40 kg/m2), and to quantify the amount of thoracic adipose tissue and muscle through advanced imaging techniques. METHODS: This is a single-center observational study including ICU-admitted patients with acute respiratory failure who underwent a chest computed tomography scan within three days before/after esophageal manometry. The superimposed pressure was calculated from lung density and height of the largest axial lung slice. Automated deep-learning pipelines segmented lung parenchyma and quantified thoracic adipose tissue and skeletal muscle. RESULTS: N = 18 participants (50% female, age 60 [30-66] years), with 9 having BMI < 30 and 9  ≥ 40 kg/m2. Groups showed no significant differences in age, sex, clinical severity scores, or mortality. Patients with BMI ≥ 40 exhibited higher esophageal pressure (15.8 ± 2.6 vs. 8.3 ± 4.9 cmH2O, p = 0.001), higher pleural pressure gradient (11.1 ± 4.5 vs. 6.3 ± 4.9 cmH2O, p = 0.04), while superimposed pressure did not differ (6.8 ± 1.1 vs. 6.5 ± 1.5 cmH2O, p = 0.59). Subcutaneous and intrathoracic adipose tissue were significantly higher in subjects with BMI ≥ 40 and correlated positively with esophageal pressure and pleural pressure gradient (p < 0.05). Muscle areas did not differ between groups. CONCLUSIONS: In patients with class III obesity, the superimposed pressure does not approximate the pleural pressure gradient, which is higher than in patients with lower BMI. The quantity and distribution of subcutaneous and intrathoracic adiposity also contribute to increased pleural pressure gradients in individuals with BMI ≥ 40. This study introduces a novel physiological concept that provides a solid rationale for tailoring mechanical ventilation in patients with high BMI, where specific guidelines recommendations are lacking.

Variability in quantitative outcomes of instrumental swallowing assessments in adults: a scoping review. / Variabilidade dos desfechos quantitativos nas avaliações instrumentais da deglutição em adultos: uma revisão de escopo.

PURPOSE: To map scientific evidence on the variability of quantitative parameters extracted by instrumental swallowing assessment tests in adults, using the coefficient of variation. RESEARCH STRATEGIES: The methodological procedures recommended by the Joanna Briggs Institute and the extension for scoping reviews of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA-ScR) were followed. SELECTION CRITERIA: The search was carried out in the Pubmed/Medline, Lilacs, Cochrane Library, Embase, Web of Science, Scopus and CINAHL databases, as well as in Google Scholar to consult the gray literature. DATA ANALYSIS: Two blind and independent reviewers screened the articles by title and abstract. Subsequently, the articles were read in full and selected according to the eligibility criteria. Data were extracted according to a standardized instrument. RESULTS: 363 studies were found, 13 of which were eligible. Most studies had a sample size of less than 30 participants and were made up of healthy individuals. The instrumental exams used were diverse: videofluoroscopy, electrical impedance tomography, laryngeal sensors, high-resolution manometry and surface electromyography. The studies searched for intra-individual variability and the coefficient of variation ranged from low to high variability, as the instruments, parameters and collection procedures were very heterogeneous and non-standardized. CONCLUSION: Intra-individual variability of the quantitative outcomes of instrumental swallowing assessments in adults ranged from low to high according to the exam, outcome, presence or absence of underlying disease, consistency and volume of the bolus.

OBJETIVO: Mapear as evidências científicas sobre a variabilidade dos parâmetros quantitativos extraídos por exames instrumentais de avaliação da deglutição em adultos, mediante o coeficiente de variação. ESTRATÉGIA DE PESQUISA: Foram seguidos os procedimentos metodológicos recomendados pelo Joanna Briggs Institute e a extensão para revisões de escopo do Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA-ScR). CRITÉRIOS DE SELEçÃO: A busca foi realizada nas bases de dados Pubmed/Medline, Lilacs, Cochrane Library, Embase, Web of Science, Scopus e CINAHL, assim como no Google Scholar para consultar a literatura cinzenta. ANÁLISE DOS DADOS: Dois revisores cegos e independentes fizeram o rastreamento dos artigos por título e resumo. Posteriormente, os artigos foram lidos na íntegra e selecionados de acordo com os critérios de elegibilidade. Os dados foram extraídos de acordo com um instrumento padronizado. RESULTADOS: Foram encontrados 363 estudos, sendo 13 elegíveis. A maioria dos estudos teve amostra menor que 30 participantes e foi composta por indivíduos saudáveis. Os exames instrumentais utilizados foram diversos: videofluoroscopia, tomografia de impedância elétrica, sensores laríngeos, manometria de alta resolução e eletromiografia de superfície. Os estudos investigaram principalmente a variabilidade intraindividual e os valores do coeficiente de variação oscilaram entre baixa e alta variabilidade, pois os instrumentos, parâmetros e procedimentos de coleta foram heterogêneos e não padronizados. CONCLUSÃO: A variabilidade intraindividual dos parâmetros quantitativos da deglutição obtidos por meio de exames instrumentais em adultos oscila entre baixa e alta conforme o exame, parâmetro testado, presença ou não de doença de base, consistência e volume do bolo alimentar.

Nocturnal Gastroesophageal Reflux and Sleep Depth in Healthy Adults, as Measured by Portable High-Resolution Manometry, Esophageal pH, and Electroencephalography.

BACKGROUND: The primary mechanism of diurnal gastroesophageal reflux (GER) is transient lower esophageal sphincter relaxation (TLESR) in both healthy persons and patients with gastroesophageal reflux disease (GERD). However, few studies have examined nocturnal GER. Using portable high-resolution manometry (HRM), esophageal pH, and electroencephalography (EEG), we investigated the association of onset of nocturnal GER with sleep depth in healthy Japanese adults. METHODS: We recruited ten healthy men (mean age 33.5 ± 4.2 years) with no reflux symptoms, no history of surgery, and no current medication use. HRM and an esophageal pH catheter were inserted in the evening. The participants returned home after consuming a test meal, and EEG was placed at home before bedtime to measure sleep depth. RESULTS: The main mechanism underlying nocturnal GER was TLESR (15/17 episodes: 88.2%). The rate of TLESR with nocturnal GER during sleep was high (51.9%, 27/52 episodes). Sleep depth during TLESR was 44.2% (23/52 times) awake and 34.6% (18/52 times) shallow sleep (N1-2). Sleep depth during TLESR with nocturnal GER was 74.0% (20/27 time) awake and 18.5% (5/27 times) shallow sleep (N1-2). CONCLUSION: The primary mechanism underlying nocturnal GER was TLESR in healthy Japanese men. TLESR and TLESR with nocturnal GER were more frequent during awakenings and shallow sleep.

Comparative Prevalence of Ineffective Esophageal Motility: Impact of Chicago v4.0 vs. v3.0 Criteria.

Background and Objectives: The threshold for ineffective esophageal motility (IEM) diagnosis was changed in Chicago v4.0. Our aim was to determine IEM prevalence using the new criteria and the differences between patients with definite IEM versus "inconclusive diagnosis". Materials and Methods: We retrospectively selected IEM and fragmented peristalsis (FP) patients from the high-resolution esophageal manometries (HREMs) database. Clinical, demographic data and manometric parameters were recorded. Results: Of 348 HREMs analyzed using Chicago v3.0, 12.3% of patients had IEM and 0.86% had FP. Using Chicago v4.0, 8.9% of patients had IEM (IEM-4 group). We compared them with the remaining 16 with an inconclusive diagnosis of IEM (borderline group). Dysphagia (77% vs. 44%, Z-test = 2.3, p = 0.02) and weight loss were more commonly observed in IEM-4 compared to the borderline group. The reflux symptoms were more prevalent in the borderline group (87.5% vs. 70.9%, p = 0.2). Type 2 or 3 esophagogastric junction morphology was more prevalent in the borderline group (81.2%) vs. 64.5% in IEM-4 (p = 0.23). Distal contractile integral (DCI) was lower in IEM-4 vs. the borderline group, and resting lower esophageal sphincter (LES) pressure and mean integrated relaxation pressure (IRP) were similar. The number of ineffective swallows and failed swallows was higher in IEM-4 compared to the borderline group. Conclusions: Using Chicago v4.0, less than 10% of patients had a definite diagnosis of IEM. The dominant symptom was dysphagia. Only DCI and the number of failed and inefficient swallows were different between definite IEM patients and borderline cases.

Gemini-Assisted Deep Learning Classification Model for Automated Diagnosis of High-Resolution Esophageal Manometry Images.

Background/Objectives: To develop a deep learning model for esophageal motility disorder diagnosis using high-resolution manometry images with the aid of Gemini. Methods: Gemini assisted in developing this model by aiding in code writing, preprocessing, model optimization, and troubleshooting. Results: The model demonstrated an overall precision of 0.89 on the testing set, with an accuracy of 0.88, a recall of 0.88, and an F1-score of 0.885. It presented better results for multiple categories, particularly in the panesophageal pressurization category, with precision = 0.99 and recall = 0.99, yielding a balanced F1-score of 0.99. Conclusions: This study demonstrates the potential of artificial intelligence, particularly Gemini, in aiding the creation of robust deep learning models for medical image analysis, solving not just simple binary classification problems but more complex, multi-class image classification tasks.

Recruitment-to-inflation ratio to assess response to PEEP during laparoscopic surgery: A physiologic study.

STUDY OBJECTIVE: During laparoscopic surgery, the role of PEEP to improve outcome is controversial. Mechanistically, PEEP benefits depend on the extent of alveolar recruitment, which prevents ventilator-induced lung injury by reducing lung dynamic strain. The hypotheses of this study were that pneumoperitoneum-induced aeration loss and PEEP-induced recruitment are inter-individually variable, and that the recruitment-to-inflation ratio (R/I) can identify patients who benefit from PEEP in terms of strain reduction. DESIGN: Sequential study. SETTING: Operating room. PATIENTS: Seventeen ASA I-III patients receiving robot-assisted prostatectomy during Trendelenburg pneumoperitoneum. INTERVENTIONS AND MEASUREMENTS: Patients underwent end-expiratory lung volume (EELV) and respiratory/lung/chest wall mechanics (esophageal manometry and inspiratory/expiratory occlusions) assessment at PEEP = 0 cmH2O before and after pneumoperitoneum, at PEEP = 4 and 12 cmH2O during pneumoperitoneum. Pneumoperitoneum-induced derecruitment and PEEP-induced recruitment were assessed through a simplified method based on multiple pressure-volume curve. Dynamic and static strain changes were evaluated. R/I between 12 and 4 cmH2O was assessed from EELV. Inter-individual variability was rated with the ratio of standard deviation to mean (CoV). MAIN RESULTS: Pneumoperitoneum reduced EELV by (median [IqR]) 410 mL [80-770] (p < 0.001) and increased dynamic strain by 0.04 [0.01-0.07] (p < 0.001), with high inter-individual variability (CoV = 70% and 88%, respectively). Compared to PEEP = 4 cmH2O, PEEP = 12 cmH2O yielded variable amount of recruitment (139 mL [96-366] CoV = 101%), causing different extent of dynamic strain reduction (median decrease 0.02 [0.01-0.04], p = 0.002; CoV = 86%) and static strain increases (median increase 0.05 [0.04-0.07], p = 0.01, CoV = 33%). R/I (1.73 [0.58-3.35]) estimated the decrease in dynamic strain (p ≤0.001, r = -0.90) and the increase in static strain (p = 0.009, r = -0.73) induced by PEEP, while PEEP-induced changes in respiratory and lung mechanics did not. CONCLUSIONS: Trendelenburg pneumoperitoneum yields variable derecruitment: PEEP capability to revert these phenomena varies significantly among individuals. High R/I identifies patients in whom higher PEEP mostly reduces dynamic strain with limited static strain increases, potentially allowing individualized settings.

Association of gastric myotomy length in peroral endoscopic myotomy (POEM) with gastro-esophageal junction distensibility measured by Endoluminal Functional Lumen Imaging Probe (EndoFLIP).

BACKGROUND: Endoluminal Functional Lumen Imaging Probe (EndoFLIP) is a device that measures gastro-esophageal junction (GEJ) distensibility. However, it is not demonstrated that GEJ distensibility increases proportionally with varying gastric myotomy length in peroral endoscopic myotomy (POEM). This study aimed to investigate the association between gastric myotomy length in POEM and intraoperative EndoFLIP findings. METHODS: This single-center, retrospective cohort study included patients who underwent POEM with intraoperative EndoFLIP from December 2019 to January 2023. Using EndoFLIP, minimal balloon diameter and its distensibility index (DI) were measured pre- and post-myotomy. Primary and secondary outcomes were the post-myotomy EndoFLIP findings at 30 ml and 40 ml volume fills. RESULTS: The study included 44 patients (mean age 53.1 years, 50% female). Chicago classification included achalasia type I (39%), II (41%), III (9%), hypercontractile esophagus (2%), and EGJOO (9%). The mean esophageal myotomy length was 7.5 ± 2.2 cm and gastric myotomy was 2.1 ± 0.6 cm. Simple linear regression analyses indicated that for each 1 cm increase in gastric myotomy length, the DI at 30 ml volume fill was estimated to increase by 2.0 mm2/mmHg (p < 0.05, R2 = 0.41), the minimal diameter at 30 ml volume fill was estimated to increase by 2.4 mm (p < 0.05, R2 = 0.48), and the minimal diameter at 40 ml volume fill was estimated to increase by 1.3 mm (p < 0.05, R2 = 0.09). CONCLUSIONS: This study demonstrates a significant linear relationship between gastric myotomy length and GEJ distensibility measured by EndoFLIP during POEM. These findings may be useful in clinical practice by enabling EndoFLIP to help calibrate a desired gastric myotomy length to achieve optimal DI and minimal diameter.

Diagnostic Utility of High-resolution Esophageal Manometry and Its Correlation with Symptoms.

BACKGROUND: Primary esophageal motility disorders present with a spectrum of symptoms where manometry plays an important role. We designed this study to evaluate the utility of esophageal manometry among various symptoms. MATERIALS AND METHODS: This is a single-center observational study conducted over 5 years in a tertiary referral center. A total of 564 patients who underwent high-resolution esophageal manometry (HREM) using a 16-channel water perfusion system were included in the study. Their clinical profile and manometric findings, as per the Chicago classification version 4.0, were recorded, and the diagnostic utility of HREM with respect to symptoms was studied. RESULTS: Motility disorders were identified in 48.8% of patients, the most common being Achalasia cardia (32.4%). Dysphagia (55.5%) was the most common indication of manometry, followed by gastroesophageal reflux disease (GERD) (34.9%), chest pain (6.2%), and symptoms such as belching, globus, and hiccoughs (3.4%). Among those who were re-classified from Chicago classification v3.0 to v4.0, 21.2% had a newer diagnosis. Among the patients with dysphagia, HREM revealed the highest yield of detecting an abnormal esophageal motility test (70.6%); meanwhile, this yield was much lower in those with GERD (21.8%), chest pain (22.8%), and other symptoms (15.7%). The most common finding among those with dysphagia was Achalasia cardia (55.9%), while the study was normal among those with GERD (78.1%), chest pain (77.1%), and other symptoms (84.2%). The sensitivity and specificity of dysphagia for major motility disorders were 65% and 91%, respectively, with a positive predictive value of 90%. CONCLUSION: HREM has high accuracy and a good diagnostic yield among patients with dysphagia, with the most common finding being Achalasia cardia.

Résumé Contexte:Les troubles primaires de la motilité œsophagienne se manifestent par un spectre de symptômes dans lesquels la manométrie joue un rôle important. Nous conçu cette étude pour évaluer l'utilité de la manométrie œsophagienne parmi divers symptômes.Matériels et méthodes:Il s'agit d'un centre unique étude observationnelle menée sur 5 ans dans un centre de référence tertiaire. Au total, 564 patients ayant subi une chirurgie œsophagienne à haute resolution la manométrie (HREM) utilisant un système de perfusion d'eau à 16 canaux ont été incluses dans l'étude. Leur profil clinique et leurs résultats manométriques, selon la classification de Chicago version 4.0, ont été enregistrés et l'utilité diagnostique du HREM en ce qui concerne les symptômes a été étudiée.Résultats:Des troubles de la motilité ont été identifiés chez 48,8 % des patients, la plus fréquente étant l'Achalasia cardia (32,4 %). La dysphagie (55,5 %) était la l'indication la plus courante de la manométrie, suivie du reflux gastro-œsophagien (RGO) (34,9 %), des douleurs thoraciques (6,2 %) et des symptômes tels que comme les éructations, les globus et le hoquet (3,4 %). Parmi ceux qui ont été reclassés de la classification de Chicago v3.0 à v4.0, 21,2 % avaient un diagnostic. Parmi les patients atteints de dysphagie, l'HREM a révélé le rendement le plus élevé de détection d'un test de motilité œsophagienne anormale (70,6 %); dans le même temps, ce rendement était beaucoup plus faible chez les personnes souffrant de RGO (21,8 %), de douleurs thoraciques (22,8 %) et d'autres symptômes (15,7 %). Le plus courant le résultat parmi les personnes souffrant de dysphagie était l'achalasie cardiaque (55,9 %), tandis que l'étude était normale chez les personnes souffrant de RGO (78,1 %), douleur thoracique (77,1 %) et autres symptômes (84,2 %). La sensibilité et la spécificité de la dysphagie pour les troubles majeurs de la motilité étaient de 65 % et 91 %, respectivement, avec une valeur prédictive positive de 90 %.Conclusion:HREM présente une grande précision et un bon rendement diagnostique chez les patients atteints de dysphagie, la pathologie la plus fréquente étant l'achalasie cardiaque.

Relevance of ineffective esophageal motility to striated esophageal muscle contraction: Studies with high-resolution manometry.

Striated esophageal muscle contraction (SEC) is important for pharyngeal swallowing and deglutition augmentation against aspiration. Its clinical relevance is unclear in patients with ineffective esophageal motility (IEM). In this study, we aimed to characterize and compare SEC in consecutive patients with and without IEM. All eligible patients were evaluated for SEC, primary and secondary peristalsis using high-resolution manometry (HRM) with one mid-esophageal injection port. Primary peristalsis was assessed with 10 5-mL liquid swallows and multiple rapid swallows (MRS), while secondary peristalsis was performed with rapid air injections of 20 mL. All peristatic parameters of HRM were measured, and SEC and its contractile integral (SECI) were evaluated. One hundred and forty patients (59.3% women, mean age 46.1 ± 13.1 years) were included. There was no difference in SECI between patients with and without IEM (p = 0.91). SECI was also similar between patients with and without secondary peristalsis for IEM (p = 0.63) or normal motility (p = 0.80). No difference in SECI was seen between patients with and without MRS for IEM (p = 0.55) or normal motility (p = 0.88). SECI was significantly higher in male patients than female patients in IEM patients (p = 0.01). SECI significantly correlated with age in patients with normal motility (r = -0.31, p = 0.01). Aging may have a negative impact on SEC in patients with normal motility, while gender difference in SECI occurs in IEM patients. Neither secondary peristalsis nor MRS influences SECI.

Determination of causes of post-operative dysphagia after anti-reflux surgery based on intra-operative planimetry.

INTRODUCTION: Dysphagia after anti-reflux surgery (ARS) is one of the most common indications for re-operative anti-reflux surgery and a leading cause of patient dissatisfaction. Unfortunately, the factors affecting its development are poorly understood. We investigated the correlation between pre-operative manometric and the intra-operative impedance planimetry (EndoFLIP™) measurements and development of post-operative dysphagia. METHODS: A review of patients who underwent index robotic ARS in our institution. Patients who underwent pre-operative manometry and intra-operative EndoFLIP™ were included in our study. Dysphagia was assessed pre-operatively and at 3-month after surgery. RESULTS: Fifty-five patients (26.9%) reported post-operative dysphagia, and 34 (16.6%) reported new or worsening dysphagia. On pre-operative manometry, patients with post-operative dysphagia had a lower distal contractile integral [868.7 (IQR 402.2-1447) mmHg s cm vs 1207 (IQR 612.1-2111) mmHg s cm, p = 0.006) and lower esophageal sphincter (LES) pressure [14.7 IQR (8.9-23.6) mmHg vs 20.7 IQR (10.2-32.6) mmHg, p = 0.01] compared to those without post-operative dysphagia. They were also found to have higher pre-operative cross-sectional surface area (CSA) [83 IQR (44.5-112) mm2 vs 66 IQR (42-93) mm2, p = 0.02], and distensibility index (DI) [4.2 IQR (2.2-5.5) mm2/mmHg vs 2.9 IQR (1.6-4.6) mm2/mmHg, p = 0.003] compared to patients without post-operative dysphagia. Additionally, the decrease in CSA [- 34 (- 18.5, - 74.5) mm2 vs - 26.5 (- 10.5, - 53.7) mm2, p = 0.03] and DI [- 2.3 (- 1.2, - 3.7) mm2/mmHg vs - 1.6 (- 0.7, - 3.3) mm2/mmHg, p = 0.03] measurements were greater in patients with post-operative dysphagia. CONCLUSION: Patients who developed dysphagia post-operatively had poorer pre-operative motility and a greater change in LES characteristics intra-operatively. This finding suggests the utility of pre-operative manometry and intra-operative EndoFLIP in identifying patients at risk of developing dysphagia post-operatively.

Regurgitation, eructation, and supragastric belch: retrograde esophageal motility, disorders, and treatment.

PURPOSE OF REVIEW: This review describes pathologic conditions of retrograde flow into the esophagus along with recent therapeutic advances and treatment options. RECENT FINDINGS: The esophagus facilitates anterograde and retrograde movement of contents, the latter of which is mediated by transient lower esophageal sphincter relaxations (TLESRs). Gastroesophageal reflux disease (GERD) often includes esophageal-specific symptoms such as heartburn or regurgitation. Volume regurgitation responds less frequently to acid suppression with proton pump inhibitors (PPIs) than heartburn, given its relationship with incompetence of the esophagogastric junction (EGJ) and increased frequency of TLESRs. Therefore, although the refluxate pH can be altered with PPIs, the frequency of reflux episodes is generally not reduced and surgical and endoscopic treatments may be favored. Other instances of abnormal retrograde esophageal flow respond better to medical therapy, or lifestyle interventions. Compared to gastric belching because of increased stomach distension, supragastric belching is caused by intake of air from pharynx into the esophagus followed by rapid expulsion of air. These conditions can be distinguished on esophageal tests such as high-resolution manometry and are likely to respond to behavioral modifications. SUMMARY: Retrograde flow into the esophagus can be a normal occurrence, but diagnostic testing to distinguish causes can guide appropriate intervention.

Muscle regeneration therapy using dedifferentiated fat cell (DFAT) for anal sphincter dysfunction.

PURPOSE: We investigated the effects of mouse-derived DFAT on the myogenic differentiation of a mouse-derived myoblast cell line (C2C12) and examined the therapeutic effects of rat-derived DFAT on anal sphincter injury using a rat model. METHODS: C2C12 cells were cultured using DMEM and DFAT-conditioned medium (DFAT-CM), evaluating MyoD and Myogenin gene expression via RT-PCR. DFAT was locally administered to model rats with anorectal sphincter dysfunction 3 days post-CTX injection. Therapeutic effects were assessed through functional assessment, including anal pressure measurement using solid-state manometry pre/post-CTX, and on days 1, 3, 7, 10, 14, 17, and 21 post-DFAT administration. Histological evaluation involved anal canal excision on days 1, 3, 7, 14, and 21 after CTX administration, followed by hematoxylin-eosin staining. RESULTS: C2C12 cells cultured with DFAT-CM exhibited increased MyoD and Myogenin gene expression compared to control. Anal pressure measurements revealed early recovery of resting pressure in the DFAT-treated group. Histologically, DFAT-treated rats demonstrated an increase in mature muscle cells within newly formed muscle fibers on days 14 and 21 after CTX administration, indicating enhanced muscle tissue repair. CONCLUSION: DFAT demonstrated the potential to enhance histological and functional muscle tissue repair. These findings propose DFAT as a novel therapeutic approach for anorectal sphincter dysfunction treatment.

The impact of gastroesophageal reflux disease on upper esophageal sphincter function: Insights from PH impedance and high-resolution manometry.

Lower esophageal sphincter (LES) pathophysiology has been established in gastroesophageal reflux disease (GERD); however, less is understood regarding the role the upper esophageal sphincter (UES) plays in preventing laryngopharynphageal reflux. Sustained UES basal pressure prevents reflux into the pharynx while allowing relaxation during ingestion. We investigate whether GERD influences UES function via HRM and pH Impedance testing. A retrospective analysis of 318 patients who underwent high-resolution manometry with trans-nasally placed manometric catheter and 24-h multichannel intraluminal impedance pH monitoring. One hundred and forty-seven patients met Lyon consensus criteria for GERD based on acid exposure time >6%. The most common chief concern was heartburn or reflux, present in 59% of these patients. Upper esophageal sphincter basal and residual pressures were not significantly different between patients with GERD when compared to those without GERD, including a subanalysis of patients with extraesophageal symptoms. The LES basal and residual pressures, DCI and MNBI are statistically lower in patients with pathologic GERD. HRM and pH Impedance testing demonstrates no difference in UES basal and residual pressures based on pH diagnosis of GERD. We redemonstrate the association with hypotonic LES, diminished DCI and MNBI with GERD.

Incorporating body mass index into esophageal manometry metrics and mean nocturnal baseline impedance for the evaluation of gastro-esophageal reflux disease.

This study aims to enhance the effectiveness of high resolution manometry (HRM) and pH-impedance monitoring metrics in distinguishing between gastro-esophageal reflux disease (GERD) and non-GERD. A retrospective propensity score matching (PSM) study was conducted on 643 patients with GERD symptoms. PSM matched 134 GERD patients with 134 non-GERD controls. Body mass index (BMI), intra-esophageal pressure (IEP) and intra-gastric pressure (IGP) were significantly higher in the GERD group compared to the non-GERD group. BMI was correlated with IEP and IGP positively. IGP was positively correlated with esophagogastric (EGJ) pressure (EGJ-P) in participants with EGJ type 1 and 2, but not in participants with EGJ type 3. BMI was correlated with distal MNBI negatively. Logistic regression showed BMI as an independent risk factor for GERD. Receiver operating characteristic curve (ROC) and decision curve analysis (DCA) showed that BMI adjusted EGJ contractile integral (EGJ-CI) and BMI adjusted MNBI were superior to the corresponding original ones in predicting GERD susceptibility. According to the findings, BMI and IGP are the main factors contributing to the development of GERD. BMI affects IEP through the adaptive response of EGJ-P to IGP. Incorporating BMI into the calculations of EGJ-CI and MNBI can improve their ability in predicting GERD susceptibility.

Review article: advances in the diagnosis and management of anorectal motility disorders.

BACKGROUND: Anorectal motility disorders such as dyssynergic defecation (DD), faecal incontinence (FI) and anorectal pain affect 40% of the population and are a frequent reason for gastroenterology consultation. They significantly affect the quality of life and lead to psychological distress. Lack of understanding of these problems compounded by a lack of availability and knowledge of diagnostic tools in most medical centres and/or trained physicians has significantly hampered this field. AIMS: To discuss the latest advances in pathophysiology, diagnostic tests and therapeutic options for these disorders using an evidence-based approach. METHODS: We reviewed the published literature over the past 20 years on DD, FI and anorectal pain and distilled these into a narrative review. RESULTS: A detailed history, prospective stool diary and digital rectal exam, together with diagnostic tests such as anorectal manometry, balloon expulsion test, translumbosacral anorectal magnetic stimulation test for assessing neuropathy, defecography and anal ultrasound, can provide detailed mechanistic and structural information. Such knowledge can pave the way for a meaningful and pathophysiologic-based management approach. This could include biofeedback therapy for DD or FI, sensory training for rectal hyposensitivity or sensory adaptation training for rectal hypersensitivity or sphincter bulking agents or neuromodulation therapies. These treatments are effective and safe. CONCLUSIONS: Anorectal motility disorders are common, but either less well recognized or poorly managed by most gastroenterologists. Equipped with the practical and up-to-date knowledge provided in this review, physicians could provide improved health care for these patients.

Continuous cuff pressure control on middle-aged and elderly patients undergoing endoscopic submucosal dissection of the esophagus effect of airway injury.

OBJECTIVE: Assessment of the effect of continuous cuff pressure control on airway injury in middle-aged and elderly patients undergoing endoscopic submucosal dissection (ESD). METHOD: A total of 104 eligible middle-aged and elderly patients requiring esophageal ESD from July 2022-September 2023 at the First Affiliated Hospital of Nanchang University were selected and randomly divided into two groups: the group undergoing general anesthesia tracheal intubation with continuous control of cuff pressure after intubation (Group A, n = 51) and the group undergoing general anesthesia tracheal intubation with continuous monitoring without control of cuff pressure (Group B, n = 53). After endotracheal intubation in Group A, under the guidance of an automatic cuff pressure controller, the air was used to inflate the tracheal cuff until the cuff pressure was 25-30cmH2O. The cuff pressure after intubation was recorded, and then the cuff pressure parameters were directly adjusted in the range of 25-30cmH2O until tracheal extubation after the operation. After endotracheal intubation, patients in Group B inflated the tracheal cuff with clinical experience, then monitored and recorded the cuff pressure with a handheld cuff manometer and instructed the cuff not to be loosened after being connected to the handheld cuff manometer-continuous monitoring until the tracheal extubation, but without any cuff pressure regulation. The patients of the two groups performed esophageal ESD. The left recumbent position was taken before the operation, and the cuff's pressure was recorded. Then, insert the gastrointestinal endoscope to find the lesion site and perform appropriate CO2 inflation to display the diseased esophageal wall for surgical operation fully. After determining the location, the cuff pressure of the two groups was recorded when the cuff pressure was stable. After the operation, the upper gastrointestinal endoscope was removed and the cuff pressure of the two groups was recorded. Postoperative airway injury assessment was performed in both groups, and the incidence of sore throat, hoarseness, cough, and blood in sputum was recorded. The incidence of postoperative airway mucosal injury was also observed and recorded in both groups: typical, episodic congestion spots and patchy local congestion. RESULT: The incidence of normal airway mucosa in Group A was higher than that in Group B (P < 0.05). In comparison, the incidence of occasional hyperemia and local plaque congestion in Group A was lower than in Group B (P < 0.05). CONCLUSION: Continuous cuff pressure control during operation can reduce airway injury in patients with esophageal ESD and accelerate their early recovery after the operation.

Enhancing the diagnostic yield of esophageal manometry using distension-contraction plots of peristalsis and artificial intelligence.

Our prior study reveals that the distension-contraction profiles using high-resolution manometry impedance recordings can distinguish patients with dysphagia symptom but normal esophageal function testing ("functional dysphagia") from control subjects. The aim of this study was to determine the diagnostic value of the recording protocol used in our prior studies (10-mL swallows with subjects in the Trendelenburg position) against the standard clinical protocol (5-mL swallows with subjects in the supine position). We used advanced machine learning techniques and robust metrics for classification purposes. Studies were performed on 30 healthy subjects and 30 patients with functional dysphagia. A custom-built software was used to extract the relevant distension-contraction features of esophageal peristalsis. Ensemble methods, i.e., gradient boost, support vector machines (SVMs), and logit boost, were used as the primary machine learning algorithms. Although the individual contraction features were marginally different between the two groups, the distension features of peristalsis were significantly different. The receiver operating characteristic (ROC) curve values for the standard recording protocol and the distension features ranged from 0.74 to 0.82; they were significantly better for the protocol used in our prior studies, ranging from 0.81 to 0.91. The ROC curve values using three machine learning algorithms were far superior for the distension than the contraction features of esophageal peristalsis, revealing a value of 0.95 for the SVM algorithm. Current patient classification for esophageal motility disorders, based on the contraction phase of peristalsis, ignores a large number of patients who have an abnormality in the distension phase of peristalsis. Distension-contraction plots should be the standard for assessing esophageal peristalsis in clinical practice.NEW & NOTEWORTHY Our findings underscore the superiority of distension features over contraction metrics in diagnosing esophageal dysfunctions. By leveraging state-of-the-art machine learning techniques, our study highlights the diagnostic potential of distension-contraction plots of peristalsis. Implementation of these plots could significantly enhance the accuracy of identifying patients with esophageal motor disorders, advocating for their adoption as the standard in clinical practice.