СУТОЧНАЯ МНОГОКАНАЛЬНАЯ РН-ИМПЕДАНСОМЕТРИЯ ПИЩЕВОДА В ДИАГНОСТИКЕ ГАСТРОЭЗОФАГЕАЛЬНОЙ РЕФЛЮКСНОЙ БОЛЕЗНИ (КЛИНИЧЕСКИЕ СЛУЧАИ)

Background. Gastroesophageal reflux disease (GERD) is an urgent problem of modern gastroenterology as well as the most common pathology of the upper gastrointestinal tract; it is a chronic disease that significantly reduces the patient's quality of life, increases the risk of developing Barrett's esophagus and esophageal adenocarcinoma. Objective. To assess the potentials of multichannel intraluminal pH impedance monitoring in the diagnosis of esophageal diseases. Material and methods. In 3 patients with clinical and endoscopic signs of GERD esophageal multichannel intraluminal pH-impedance monitoring was performed using the diagnostic equipment Digitrapper pH-Z from Given Imaging (USA). Results. 24-hour esophageal pH monitoring enabled to verify the diagnosis of GERD, to reveal a hypersensitive esophagus and manifestations of nocturnal acid breakthrough. Conclusions. Multichannel intraluminal pH-impedance monitoring is the "gold standard" for the diagnosis of esophageal diseases; it significantly expands opportunities of gastroenterologists in the treatment of GERD.

Possibilities of pH impedance and high-resolution manometry in managing patients with refractory gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common condition that has a substantial impact on quality of life in patients and is a leading risk factor for esophageal adenocarcinoma. Now therapy with proton pump inhibitors (PPIs) is a basic method in the treatment of patients with GERD; however, one third of the patients do not respond to the therapy used. The causes of refractory GERD are a fairly large group of heterogeneous factors contributing to the inefficacy of PPIs in adequate dosage. Among these factors, there is low compliance by patients to the prescribed treatment regimen; nocturnal acid breakthrough; СУР2С19 gene polymorphism; chiasm syndrome with functional diseases of the gastrointestinal tract; non-acidic refluxes in a patient; thoracic esophageal motility disorders; the increased number and duration of transient lower esophageal sphincter relaxation periods; hiatus hernia; and misdiagnosis. 24-hour pH impedance and high-resolution esophageal manometry are now the most informative diagnostic techniques in patients who fail to respond to PPI therapy. These techniques allow one to timely recognize the causes of refractory GERD, to make a differential diagnosis with other nosological entities, and to timely correct therapy for each individual patient.

New Insights Into the Propagation of Emulsified Acids in Vuggy Dolomitic Rocks

Summary Carbonate formations are very complex in their pore structure and exhibit a wide variety of pore classes, such as interparticle porosity, moldic porosity, vuggy porosity, intercrystalline porosity, and microporosity. Understanding the role of pore class in the performance of emulsified-acid treatments and characterizing the physics of the flow in the acid propagation are the objectives of our study. The study was performed by use of vuggy-dolomite cores that represent mainly the vuggy-porosity-dominated structure, whereas the homogeneous cores used represent the intercrystalline pore structure. Coreflood experiments were conducted on 6 × 1.5-in. cores by use of emulsified acid formulated at 1 vol% emulsifier and 0.7 acid volume fraction. The objective of this set of experiments is to determine the acid pore volume (PV) to breakthrough for each carbonate pore class at different injection flow rates. In this paper, we examine whether the heterogeneities observable at the thin-section scale have a significant influence on the results of the emulsified-acid coreflood experiments. The heterogeneities were characterized by use of thin-section observations, tracer experiments, scanning electron microscopy (SEM), and resistivity measurements. Thin-section observations provide means to study the size of vugs and their distribution and connectivity, and to explain the contribution of the pore class in the acid propagation. Also, the rotating-disk experiments of emulsified acid with dolomite were related to our coreflood experimental results. The acid PV to breakthrough for vuggy-porosity-dominated rocks, ranging from 0.1 to 0.3, was observed to be low when compared with homogeneous carbonates (intercrystalline pore structure) with PVbt ranging from 2.5 to 3.5. Also, the wormhole dissolution pattern was found to be significantly different in vuggy rocks than that in homogeneous ones. Thin-section observations, tracer results, and the coreflood experiments indicate that the vugs are distributed in a manner that creates a preferential flow path, which can cause a rapid acid breakthrough and effective wormholing rather than those with a uniform pore structure. The rotating-disk results also showed that the reaction kinetics played a role in determining the wormhole pattern.