Three-Dimensional Fractal Analysis of the Interstitial Cells of Cajal Networks of Gastrointestinal Tissue Specimens.

Introduction: Several functional gastrointestinal disorders (FGIDs) have been associated with the degradation or remodeling of the network of interstitial cells of Cajal (ICC). Introducing fractal analysis to the field of gastroenterology as a promising data analytics approach to extract key structural characteristics that may provide insightful features for machine learning applications in disease diagnostics. Fractal geometry has advantages over several physically based parameters (or classical metrics) for analysis of intricate and complex microstructures that could be applied to ICC networks. Methods: In this study, three fractal structural parameters: Fractal Dimension, Lacunarity, and Succolarity were employed to characterize scale-invariant complexity, heterogeneity, and anisotropy; respectively of three types of gastric ICC network structures from a flat-mount transgenic mouse stomach. Results: The Fractal Dimension of ICC in the longitudinal muscle layer was found to be significantly lower than ICC in the myenteric plexus and circumferential muscle in the proximal, and distal antrum, respectively (both p < 0.0001). Conversely, the Lacunarity parameters for ICC-LM and ICC-CM were found to be significantly higher than ICC-MP in the proximal and in the distal antrum, respectively (both p < 0.0001). The Succolarity measures of ICC-LM network in the aboral direction were found to be consistently higher in the proximal than in the distal antrum (p < 0.05). Conclusions: The fractal parameters presented here could go beyond the limitation of classical metrics to provide better understanding of the structural-functional relationship between ICC networks and the conduction of gastric bioelectrical slow waves.

Gastric point-of-care ultrasonography in patients undergoing radical gastrointestinal surgery before anesthetic induction: an observational cohort study.

BACKGROUND: Pulmonary aspiration of gastric contents is a serious perioperative complication. Patients with gastric cancer may experience delayed gastric emptying. However, the role of qualitative and quantitative gastric ultrasound assessments in this patient population before anesthesia induction has not yet been determined. METHODS: Adult patients with gastrointestinal cancer were recruited and examined using gastric point-of-care ultrasound (POCUS) before anesthetic induction from March 2023 to August 2023 in a tertiary cancer center. Three hundred patients with gastric cancer were conducted with POCUS prior to induction, and three hundred patients with colorectal cancer were included as controls. The cross-sectional area (CSA) of the gastric antrum and gastric volumes (GV) were measured and calculated. We determined the nature of the gastric contents and classified the antrum using a 3-point grading system. A ratio of GV to body weight > 1.5mL/Kg was defined as a high risk of aspiration. RESULTS: In patients with gastric cancer, 70 patients were classified as grade 2 (23%, including 6 patients with solid gastric contents) and 63 patients (21%) were identified as having a high risk of aspiration. Whereas in patients with colorectal cancer, only 11 patients were classified as grade 2 (3.7%), and 27 patients (9.7%) were identified as having a high risk of aspiration. A larger tumor size (OR:1.169, 95% CI 1.045-1.307, P = 0.006), tumor located in antrum (OR:2.304, 95% CI 1.169-4.539,P = 0.016), gastrointestinal obstruction (OR:21.633, 95% CI 4.199-111.443, P < 0.0001) and more lymph node metastasis (OR:2.261, 95% CI 1.062-4.812, P = 0.034) were found to be positively while tumor site at cardia (OR:0.096, 95% CI 0.019-0.464, P = 0.004) was negatively associated with high aspiration risk in patients with gastric cancer. CONCLUSION: The Gastric POCUS prior to induction provides an assessment of the status of gastric emptying and can identify the patients at high risk of aspiration, especially those with gastric cancer. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( www.chictr.org.cn ) identifier: ChiCTR2300069242; registered 10 March 2023.

Clinical analysis of helicobacter pylori biopsy in gastric antrum / 中国内镜杂志

Objective To analyze the detection of helicobacter pylori(Hp)in different parts of gastric antrum,and to provide clinical guidance for finding the best biopsy site for Hp.Methods Patients who underwent 13C urea breath test and electronic gastroscopy from January 2020 to December 2022 were retrospectively analyzed and divided into 13C urea breath test positive group[delta over baseline(DOB)≥4]and 13C urea breath test negative group(DOB<4)according to DOB value.Gastroscopy reports and pathological data of patients were collected.According to different biopsy sites in gastric antrum,patients were divided into conventional biopsy site group,elevated erosive site group and flat erosive site group,and the detection rate of Hp in different biopsy sites was compared.13C urea breath test positive group was divided into group A(4<DOB≤16),group B(16<DOB≤35)and group C(DOB>35)according to DOB value,and the gastric antral biopsy and pathology of each group were classified and analyzed.Combined with endoscopic reports and pathological data,patients were divided into atrophic gastritis group and non-atrophic gastritis group.Results In the 13C urea breath test positive group,the detection rate of Hp in the elevated erosive site group(96.4%)was higher than that in the conventional biopsy site group(92.7%)and the flat erosive site group(93.9%),and the difference was statistically significant(P = 0.036).In DOB group A,the detection rate of Hp was the highest at the site of elevated erosive and the lowest at the site of conventional biopsy,and the detection rate of Hp at the three biopsy sites was compared,the difference was statistically significant(P = 0.016);There was no significant difference in the detection rate of Hp at three biopsy sites between group B and group C(P = 0.622;P = 0.721);the non-atrophic gastritis group,the detection rate of Hp at the elevated erosive site(96.5%)was higher than that at the conventional biopsy site(91.2%)and the flat erosive site(92.0%),and the difference was statistically significant(P = 0.043).There was no significant difference in the detection rate of Hp at three biopsy sites in the atrophic gastritis group(P = 0.614).13C urea breath test negative group:There was no significant difference in Hp detection rate among the three biopsy sites(P = 0.255).Conclusion For patients with positive 13C urea breath test but low DOB value,the positive rate of Hp in the elevated erosive site is higher.For non-atrophic gastritis patients,the detection rate of Hp was higher in the elevated erosive sites than in the conventional biopsy sites.But for patients with atrophic gastritis,there was little difference in the detection rate of Hp in different parts of antrum.For patients with negative 13C urea breath test,there was no significant difference in Hp detection rate among the three biopsy sites.In future clinical work,for similar patients,precise biopsy can be performed to improve the detection rate of Hp.

Hedysari Radix Polysaccharide Regulates Apoptosis of Smooth Muscle Cells in Gastric Antrum of Rat Model of Diabetic Gastroparesis via IGF-1/PI3K/Akt Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effects of Hedysari Radix polysaccharide on the apoptosis of gastric sinus smooth muscle cells and explore the underlying mechanism via the insulin-like growth factor-1 （IGF-1）/phosphatidylinositol 3-kinase （PI3K）/serine-threonine kinase （Akt） pathway in the rat model of diabetic gastroparesis （DGP）. MethodSixty-two Wistar male rats were randomized into a blank group （n=12） and a modelling group （n=50）. The rat model of DGP was established by small-dose multiple intraperitoneal injections of streptozotocin combined with an irregular high-fat and high-sugar diet for 4 weeks. The modeled rats were randomized into model group， mosapride citrate （1.35 mg·kg-1）， and high-， medium-， and low-dose （200， 100， and 50 mg·kg-1， respectively） Hedysari Radix polysaccharide groups. The rats were administrated with corresponding drugs by gavage， and those in the blank and model groups with equal volumes of pure water by gavage once a day for 8 consecutive weeks. The random blood glucose and body mass were measured every 2 weeks， and gastric emptying rate was calculated. Hematoxylin-eosin （HE） staining was used to observe the pathological changes of smooth muscle in gastric antrum， and terminal deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to detect the apoptosis of smooth muscle cells in the gastric antrum. The expression of IGF-1， phosphorylated （p）-PI3K， and p-Akt in the smooth muscle of gastric sinus tissue was detected by immunohistochemistry. Western blot was employed to determine the protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） in the smooth muscle of the gastric antrum. ResultCompared with the blank group， the model group showed elevated random blood glucose at all time points （P<0.01）， decreased body mass and gastric emptying rate （P<0.01）， increased apoptotic index of smooth muscle cells in the gastric antrum （P<0.01）， down-regulated protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， and Bcl-2， and up-regulated protein level of Bax （P<0.01）. Compared with the model group， the 8 weeks of drug administration lowered the random blood glucose， increased the body mass and gastric emptying rate （P<0.05， P<0.01）， decreased the apoptotic index of smooth muscle cells in the gastric antrum （P<0.05， P<0.01）， up-regulated the protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， and Bcl-2， and down-regulated the protein level of Bax （P<0.05， P<0.01）. Compared with the mosapride citrate group，the administration of low-dose Hedysari Radix polysaccharide for 6 and 8 weeks lowered the random blood glucose and decreased the body mass （P<0.05， P<0.01），low and medium-dose Hedysari Radix polysaccharide decreased the gastric emptying rate and the apoptotic index of smooth muscle cells in the astragaloside low-dose group decreased （P<0.05）. The protein levels of IGF-1，p-PI3K/PI3K，p-Akt/Akt and Bcl-2（low dose）were down-regulated and the protein level of Bax was up-regulated by low doses of Hedysari Radix polysaccharide （P<0.05， P<0.01）. Compared with high-dose Hedysari Radix polysaccharide， low-dose Hedysari Radix polysaccharide elevated random blood glucose and reduced body mass after 6 and 8 weeks of administration （P<0.05， P<0.01）， and the low and medium doses decreased the gastric emptying rate， increased the apoptotic index of smooth muscle cells in the gastric antrum （P<0.05， P<0.01）， down-regulated the protein levels of IGF-1， p-PI3K/PI3K， p-Akt/Akt， and Bcl-2， and up-regulated the protein level of Bax （P<0.05， P<0.01）. Compared with the medium-dose group，the low-dose group of Hedysari Radix polysaccharide had lower body mass，lower gastric emptying rate in rats，higher apoptotic index of smooth muscle cells in gastric sinus tissue after 6 and 8 weeks of administration （P<0.05， P<0.01）， and lower protein expression of IGF-1，p-PI3K/PI3K，p-Akt/Akt. ConclusionHedysari Radix polysaccharide protects the smooth muscle cells in gastric antrum against apoptotic injury and promotes gastric motility by activating the IGF-1/PI3K/Akt signaling pathway， as manifested by the up-regulated expression of IGF-1， p-PI3K， p-Akt， and Bcl-2 and down-regulated expression of Bax.

Prediction of prokinetic agents in critically ill patients with feeding intolerance: a prospective observational clinical study.

Background: Prokinetic agents are currently considered the first-line therapy to improve gastric emptying when feeding intolerance occurred in critically ill adults. In this study, we developed a technique to assess the feasibility of predicting prokinetic agent efficacy in critically ill patients. Methods: The first images of each patient were obtained after EFI had occurred but before the first dose of prokinetic agents was administered and additional images were obtained every morning until the seventh day. The gastric antrum echodensity was recorded based on grayscale values (50th percentile, ED50; 85th percentile, ED85; mean, EDmean) and daily energy and protein intake was collected as the judgment for effective and ineffective group. A receiver operating characteristic curve was analyzed to distinguish the thresholds between the two groups and thus determine the ability of the gastric antrum echodensity to predict the efficacy of prokinetic agents. Results: In total, 83 patients were analyzed. Patients in the ineffective group had a higher ED50 (58.13 ± 14.48 vs. 49.88 ± 13.78, p < 0.001, difference 95% CI: 5.68, 10.82), ED85 (74.81 ± 16.41 vs. 65.70 ± 16.05, p < 0.001, difference 95% CI:6.16, 12.05), and EDmean (60.18 ± 14.31 vs. 51.76 ± 14.08, p < 0.001, difference 95% CI: 5.85, 11.00) than those in the effective group. Patients in the effective group more easily reached the target energy 16.21 ± 7.98 kcal/kg vs. 9.17 ± 6.43 kcal/kg (p < 0.001), 0.72 ± 0.38 g/kg vs. 0.42 ± 0.31 g/kg (p < 0.001) than in the ineffective group intake by day. Conclusion: The gastric antrum echodensity might serve as a tool for judging the efficacy of prokinetic agents, helping clinicians to decide whether to use prokinetic agents or place a post-pyloric tube when feeding intolerance occurs in critically ill patients.Clinical trial registration:http://www.chictr.org.cn/addproject2.aspx, ChiCTR2200058373. Registered 7 April 2022.

Ultrasonographic Evaluation of Gastric Content and Volume in Pediatric Patients Undergoing Elective Surgery: A Prospective Observational Study.

Anesthesia-related complications, such as pulmonary aspiration of gastric contents, occur in approximately 0.02-0.1% of elective pediatric surgeries. Aspiration risk can be reliably assessed by ultrasound examination of the gastric antrum, making it an essential non-invasive bedside tool. In this prospective observational study, since most of our patients are immigrants and have communication problems, we wanted to investigate gastric contents and the occurrence of "high risk stomach" in children undergoing elective surgery for the possibility of pulmonary aspiration, even if the children and/or parents reported their last oral intake time. This risk is defined by ultrasound findings of solid content in the antrum and/or a calculated gastric volume exceeding 1.25 mL/kg. Children aged 2-18 were included in the study. Both supine and right lateral decubitus (RLD) ultrasound examinations were performed on the antrum before surgery. Using a qualitative grading scale from 0 to 2, we evaluated the gastric fluid content. The cross-sectional area (CSA) of the antrum was measured in the RLD position, aiding the calculation of the gastric fluid volume according to an established formula by Perlas. Ultrasound measurements of 97 children were evaluated. The median fasting duration was 4 h for liquids and 9 h for thick liquids and solids. Solid content was absent in all the children. Five children (5.2%) exhibited a grade 2 antrum, implying that fluid content was visible in both the supine and RLD positions. The median antral CSA in the RLD was 2.36 cm2, with a median gastric volume of 0.46 mL/kg. For patients with a grade 0 antrum, a moderate and positive correlation was observed between the antral CSA and BMI, and a strong and positive correlation was evident between the antral CSA and age, similar to a grade 1 antrum. Only a single child (1%) had a potentially elevated risk of aspiration of gastric contents. Hence, the occurrence of a "high risk stomach" was 1% (95% confidence interval: 0.1-4.7%) and is consistent with the literature. As a necessary precaution, we propose the regular use of ultrasound evaluations of gastric contents, given their non-invasive, bedside-friendly, and straightforward implementation, for identifying risks when fasting times are uncertain and for ruling out unknown risk factors in each potential patient.

Cross-species single-cell transcriptomic analysis of animal gastric antrum reveals intense porcine mucosal immunity.

As an important part of the stomach, gastric antrum secretes gastrin which can regulate acid secretion and gastric emptying. Although most cell types in the gastric antrum are identified, the comparison of cell composition and gene expression in the gastric antrum among different species are not explored. In this study, we collected antrum epithelial tissues from human, pig, rat and mouse for scRNA-seq and compared cell types and gene expression among species. In pig antral epithelium, we identified a novel cell cluster, which is marked by high expression of AQP5, F3, CLCA1 and RRAD. We also discovered that the porcine antral epithelium has stronger immune function than the other species. Further analysis revealed that this may be due to the insufficient function of porcine immune cells. Together, our results replenish the information of multiple species of gastric antral epithelium at the single cell level and provide resources for understanding the homeostasis maintenance and regeneration of gastric antrum epithelium.

Assessment of Gastric Residual Volume with Ultrasound in Children at Fasting and after Oral Intake of Carbohydrate-Rich Fluid in the Preoperative Period.

Purpose: Despite standard preoperative fasting guidelines, children are subjected to prolonged fasting due to various reasons. This does not reduce gastric residual volume (GRV) further, instead causes hypoglycemia, hypovolemia, and unnecessary discomfort. We calculated the cross-sectional area (CSA) of antrum and GRV in children in fasting state and 2 h after intake of oral carbohydrate-rich fluid, using gastric ultrasound. Methods: Anteroposterior and craniocaudal gastric antral diameters were measured by ultrasonography in the right lateral decubitus position, at fasting and at 2 h after 8 ml/kg of pulp-free fruit juice ingestion. CSA of antrum and GRV was calculated using validated mathematical models. Results: Data of 149 children of age >1-12 years were analyzed. Greater than ninety-nine percent of children emptied ≥95% of the ingested pulp-free fruit juice volume within 2 h. One hundred and seven (71.8%) children had reduced CSA and GRV at 2 h after fruit juice ingestion (2.01 ± 1.00 cm2 and 7.77 ± 6.81 ml) as compared to fasting state (3.18 ± 1.40 cm2 and 11.89 ± 7.80 ml). Fourty-nine (28.2%) children had slightly increased CSA and GRV at 2 h after fruit juice (2.46 ± 1.14 cm2 and 10.61 ± 7.26 ml) than at fasting (1.89 ± 0.92 cm2 and 8.61 ± 6.75 ml), but this increased GRV was grossly lower than limit of risk stomach (26.54 ± 8.95 ml). Conclusion: Carbohydrate-rich drink in the form of pulp-free fruit juice may be safely permitted up to 2 h before anesthetic induction, as it promoted gastric emptying in ≈ 72% of children and 28% of children, although GRV was slightly higher at 2 h after fruit juice ingestion than fasting but remained considerably lower than limit of risk stomach.

Reinforcing the valuable role of gastric ultrasound for volume and content assessment: an observational study

Abstract Background Pulmonary aspiration is one of the most important complications in anesthesiology. Assessment of gastric content by ultrasound is a good method to quantify gastric volume and to determine the risk of intraoperative pulmonary aspiration. The aim of this study is to determine the accuracy of the gastric ultrasonography in the qualitative analysis of gastric content, mainly in the analysis of small amounts of liquid content. Methods Gastric ultrasound was performed to 36 patients before upper gastrointestinal endoscopy (UGI), making two longitudinal scans at the epigastric level, one in supine position and the other in right lateral decubitus position, measuring two diameters and the area of the gastric antrum and assessing the content characteristics determining whether it was an empty stomach or contained fluid or solid content. Subsequently, the ultrasound findings were compared with UGI findings. Results Gastric areas were analyzed by the trace and the lengths of the craniocaudal and anteroposterior axes concluding that there are no significant differences between the two methods. No statistically significant difference was found between UGI and US assessment technics. No statistically significant difference was found between the estimated volume by UGI and US. Conclusions Though our study has some limitations, qualitative analysis of gastric content using ultrasound followed by endoscopy enabled the conclusion that there are no differences in the qualitative assessment regarding these two techniques, supporting the important role of point-of-care gastric ultrasound (POCGUS) in the assessment of pulmonary aspiration risk by the anesthesiologist in the perioperative period.

Comparison of Gastric Insufflation Volume Between Ambu AuraGain and ProSeal Laryngeal Mask Airway Using Ultrasonography in Patients Undergoing General Anesthesia: A Randomized Controlled Trial.

INTRODUCTION: Ambu AuraGain and ProSeal laryngeal mask airway are second-generation supraglottic airway devices (SADs) with added advantage of gastric drain and better oropharyngeal sealing pressure. The primary objective was to study the difference in the gastric insufflation volume between Ambu AuraGain and ProSeal LMA in patients undergoing general anesthesia. METHODS: This randomized controlled trial involving 120 adult patients scheduled under general anesthesia were randomized into either Ambu AuraGain or LMA ProSeal group. Gastric cross-sectional area was measured using ultrasonography at baseline, after mask ventilation, and at the end of surgery. Gastric volume was calculated from the measured cross-sectional area. Oropharyngeal sealing pressure, peak airway pressure, and postoperative complications were noted. Statistical analysis was done using SPSS version 22 (Armonk, NY: IBM Corp.) and p < 0.05 was considered statistically significant. RESULTS: Demographic profile of the study groups was comparable. There was a significant difference in gastric volume between the groups at the end of surgery with 5.91 ml (±9.68 ml) in Ambu AuraGain group and 12.28 ml (±13.05 ml) in the LMA ProSeal group (p = 0.001). Similarly, there was a difference in volume between baseline and at the end of the surgery within the groups also (Ambu AuraGain group, p=0.0012; LMA ProSeal group, p=0.0015, respectively). Though the oropharyngeal sealing pressure and peak airway pressures were comparable, increased incidence of postoperative complications was observed with LMA ProSeal. CONCLUSION: Thus, Ambu AuraGain resulted in a lower gastric insufflation volume than LMA ProSeal with lesser incidence of postoperative complications.

[Is pre-oxygenation with high-flow nasal oxygen safe? randomized control trial of 56 cases of elderly patients during induction of general anesthesia with endotracheal intubation].

OBJECTIVE: To evaluate the safety of preoxygenation with high-flow nasal oxygenation in elderly patients during induction of general anesthesia with endotracheal intubation. METHODS: Fifty-six elderly patients without difficult airway were randomized equally into high-flow nasal oxygen group (HF group) and conventional mask oxygen group (M group). Preoxygenation was performed for 5 min before induction of general anesthesia and endotracheal intubation. Oxygenation was maintained during laryngoscopy in HF group, and ventilation lasted until laryngoscopy in M group. For all the patients, the general data, cross-sectional area (CSA) of the gastric antrum measured by ultrasonography, arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2) and arterial oxygen saturation (cSO2) were recorded before preoxygenation (T1), at 5 min of preoxygenation (T2) and immediately after intubation (T3). The safety time of asphyxia, intubation time, times of mask ventilation and postoperative complications were compared between the two groups. RESULTS: The general data were comparable between the two groups. After 5 min of preoxygenation, PaO2 and cSO2 were significantly increased in both groups, and PaO2 was significantly higher in HF group than in M group (F=118.108 vs 9.511, P < 0.05). Both PaO2 and cSO2 decreased after intubation, but PaO2 decreased more slowly in HF group and still remained higher than that at T1; cSO2 decreased significantly in M group to a lower level than that at T1. Compared with those in M group, the patients in HF group showed a significantly longer safety time of asphyxia (t=5.305, P < 0.05) with fewer times of mask ventilation (χ2= 6.720, P < 0.05). PaCO2 increased after intubation in both groups but was comparable between the two groups (F=3.138, P > 0.05). CONCLUSION: High-flow nasal oxygen is safe, simple and effective for pre-oxygenation, which, as compared with the conventional oxygen mask, improves arterial oxygen partial pressure and prolongs the safety time of asphyxia to ensure the safety of airway management during induction of general anesthesia in elderly patients with endotracheal intubation.

Ultrasound-Determined Residual Gastric Volume after Clear-Fluid Ingestion in the Paediatric Population: Still a Debatable Issue.

Background: Current fasting guidelines are often exceeded in clinical practice, resulting in stressful events during anaesthesia in children. This prospective study compares residual gastric volume after 1 versus 2 h of clear fluid ingestion in fasted children. METHODS: A total of 106 patients were enrolled in the study. Ultrasonography (USG) of gastric antrum (GA) was performed in the supine and right lateral decubitus (RLD) positions. All children fasted from solid food for 6 h. Blackcurrant flavoured drink (3 mL/kg) was given following the measurement of baseline (T0) USG of GA, with follow-ups after 1 (T1) and 2 (T2) hours post-ingestion. Residual gastric volume (RGV) was calculated from the cross-sectional area of GA using a standard formula. Parental satisfaction with their children's behaviour concerning fasting time was recorded. Results: RGV was significantly higher at T1 compared to T2 (p < 0.001). No significant difference was seen between T0 and T2 (p = 0.30). Parental satisfaction was similar at T1 and T2 (p = 0.158). Conclusions: The RGV in paediatric patients after 1 h of clear fluid ingestion was significantly higher than after 2 h of ingestion. There was no difference observed in parental satisfaction concerning the two intervals of fluid fasting. RLD and supine positions can be used reliably to measure the RGV in children.

Association of Gastric Antrum Echodensity and Acute Gastrointestinal Injury in Critically Ill Patients.

(1) Background: Acute muscle inflammation leads to increased sonographic echodensity. We developed a technique to characterize the echodensity of the gastric antrum wall and assess its feasibility in evaluating the severity of acute gastrointestinal injury (AGI); (2) Methods: The B-mode images of the gastric antrum of each enrolled patient were obtained daily by point-of-care ultrasound (POCUS). The 50th percentile, 85th percentile, and mean value of the grayscale distribution according to histogram analysis (ED50, ED85, and EDmean, respectively) were used to characterize the gastric antrum echodensity. Consistency and correlation analyses were performed to evaluate the feasibility and reproducibility of gastric antrum echodensity measurement. The association of gastric antrum echodensity with the severity of AGI and its ability to predict feeding intolerance (FI) were analyzed; (3) Results: In total, 206 POCUS images of 43 patients were analyzed. The gastric antrum echodensity measurements had sufficient intra- and inter-investigator reliabilities (intraclass correlation coefficient >0.9 for all parameters). The ED50 showed a significant upward trend as AGI severity increased, as well as ED85 and EDmean (p for trend <0.001, respectively). Patients who experienced FI had a higher ED50 (67.8 vs. 56.1, p = 0.02), ED85 (85.6 vs. 71.2, p = 0.01), and EDmean (70.3 vs. 57.6, p = 0.01) upon enteral feeding initiation; (4) Conclusions: Measurement of gastric antrum echodensity was technically feasible and reproducible in ventilated patients. Increased gastric antrum echodensity was associated with greater severity of AGI. Patients with higher gastric antrum echodensity upon enteral nutrition initiation via a nasogastric tube were more likely to develop FI.

Reinforcing the valuable role of gastric ultrasound for volume and content assessment: an observational study.

BACKGROUND: Pulmonary aspiration is one of the most important complications in anesthesiology. Assessment of gastric content by ultrasound is a good method to quantify gastric volume and to determine the risk of intraoperative pulmonary aspiration. The aim of this study is to determine the accuracy of the gastric ultrasonography in the qualitative analysis of gastric content, mainly in the analysis of small amounts of liquid content. METHODS: Gastric ultrasound was performed to 36 patients before upper gastrointestinal endoscopy (UGI), making two longitudinal scans at the epigastric level, one in supine position and the other in right lateral decubitus position, measuring two diameters and the area of the gastric antrum and assessing the content characteristics determining whether it was an empty stomach or contained fluid or solid content. Subsequently, the ultrasound findings were compared with UGI findings. RESULTS: Gastric areas were analyzed by the trace and the lengths of the craniocaudal and anteroposterior axes concluding that there are no significant differences between the two methods. No statistically significant difference was found between UGI and US assessment technics. No statistically significant difference was found between the estimated volume by UGI and US. CONCLUSIONS: Though our study has some limitations, qualitative analysis of gastric content using ultrasound followed by endoscopy enabled the conclusion that there are no differences in the qualitative assessment regarding these two techniques, supporting the important role of point-of-care gastric ultrasound (POCGUS) in the assessment of pulmonary aspiration risk by the anesthesiologist in the perioperative period.

Ultrasound assessment of gastric contents prior to placental delivery: A prospective multicentre cohort study.

BACKGROUND: There is ongoing debate regarding the optimal general anaesthetic technique for manual removal of the placenta after vaginal delivery. Using ultrasound examination of the gastric antrum, this study aimed to assess the change in gastric contents during vaginal delivery and to determine the prevalence of stomach at risk for pulmonary aspiration in the immediate postpartum period before placental delivery. METHODS: In this prospective multicentre cohort study, antral ultrasonography was performed at full cervical dilatation within the thirty minutes preceding the beginning of expulsive efforts and after vaginal birth, before placental delivery. High-risk gastric content was defined as the visualisation of any solid content in the antrum or antral cross-sectional area in the semi-recumbent position (SR-CSA) > 608 mm². RESULTS: Twenty-six women were included and analysed. There was a significant decrease in both the proportion of patients with solid gastric content and the SR-CSA between the two-ultrasound examinations. Twenty-one patients (80.8%) exhibited a decrease in the SR-CSA during vaginal delivery. The prevalence of stomach at risk for pulmonary aspiration was significantly lower after vaginal delivery than before vaginal delivery (23.1% vs. 57.7%, P = 0.0004). CONCLUSION: Our results suggest that gastric emptying is at least partially preserved during vaginal birth. Nevertheless, almost a quarter of women did have high-risk gastric content in the immediate postpartum period. Point-of-care antral ultrasonography may be of interest for the fast assessment of the gastric content status when a general anaesthesia is required for manual removal of retained placenta.

Is pre-oxygenation with high-flow nasal oxygen safe? randomized control trial of 56 cases of elderly patients during induction of general anesthesia with endotracheal intubation / 南方医科大学学报

OBJECTIVE@#To evaluate the safety of preoxygenation with high-flow nasal oxygenation in elderly patients during induction of general anesthesia with endotracheal intubation.@*METHODS@#Fifty-six elderly patients without difficult airway were randomized equally into high-flow nasal oxygen group (HF group) and conventional mask oxygen group (M group). Preoxygenation was performed for 5 min before induction of general anesthesia and endotracheal intubation. Oxygenation was maintained during laryngoscopy in HF group, and ventilation lasted until laryngoscopy in M group. For all the patients, the general data, cross-sectional area (CSA) of the gastric antrum measured by ultrasonography, arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2) and arterial oxygen saturation (cSO2) were recorded before preoxygenation (T1), at 5 min of preoxygenation (T2) and immediately after intubation (T3). The safety time of asphyxia, intubation time, times of mask ventilation and postoperative complications were compared between the two groups.@*RESULTS@#The general data were comparable between the two groups. After 5 min of preoxygenation, PaO2 and cSO2 were significantly increased in both groups, and PaO2 was significantly higher in HF group than in M group (F=118.108 vs 9.511, P < 0.05). Both PaO2 and cSO2 decreased after intubation, but PaO2 decreased more slowly in HF group and still remained higher than that at T1; cSO2 decreased significantly in M group to a lower level than that at T1. Compared with those in M group, the patients in HF group showed a significantly longer safety time of asphyxia (t=5.305, P < 0.05) with fewer times of mask ventilation (χ2= 6.720, P < 0.05). PaCO2 increased after intubation in both groups but was comparable between the two groups (F=3.138, P > 0.05).@*CONCLUSION@#High-flow nasal oxygen is safe, simple and effective for pre-oxygenation, which, as compared with the conventional oxygen mask, improves arterial oxygen partial pressure and prolongs the safety time of asphyxia to ensure the safety of airway management during induction of general anesthesia in elderly patients with endotracheal intubation.

Xiangbinfang granules enhance gastric antrum motility via intramuscular interstitial cells of Cajal in mice.

BACKGROUND: Interdigestive migrating motor complexes (MMC) produce periodic contractions in the gastrointestinal tract, but the exact mechanism of action still remains unclear. Intramuscular interstitial cells of Cajal (ICC-IM) participate in gastrointestinal hormone and neuromodulation, but the correlation between ICC-IM and MMC is also unclear. We found that xiangbinfang granules (XBF) mediated the phase III contraction of MMC. Here, the effects of XBF on gastric antrum motility in W/W v mice and the effects of ICC-IM on gastric antrum MMC are reported. AIM: To observe the effects of ICC-IM on gastric antrum motility and to establish the mechanism of XBF in promoting gastric antrum motility. METHODS: The density of c-kit-positive ICC myenteric plexus (ICC-MP) and ICC-IM in the antral muscularis of W/W v and wild-type (WT) mice was examined by confocal microscopy. The effects of XBF on gastric antrum slow waves in W/W v and WT mice were recorded by intracellular amplification recording. Micro-strain-gauge force transducers were implanted into the gastric antrum to monitor the MMC and the effect of XBF on gastric antrum motility in conscious W/W v and WT mice. RESULTS: In the gastric antrum of W/W v mice, c-kit immunoreactivity was significantly reduced, and no ICC-IM network was observed. Spontaneous rhythmic slow waves also appeared in the antrum of W/W v mice, but the amplitude of the antrum slow wave decreased significantly in W/W v mice (22.62 ± 2.23 mV vs 2.92 ± 0.52 mV, P < 0.0001). MMCs were found in 7 of the 8 WT mice but no complete MMC cycle was found in W/W v mice. The contractile frequency and amplitude index of the gastric antrum were significantly increased in conscious WT compared to W/W v mice (frequency, 3.53 ± 0.18 cpm vs 1.28 ± 0.12 cpm; amplitude index, 23014.26 ± 1798.65 mV·20 min vs 3782.16 ± 407.13 mV·20 min; P < 0.0001). XBF depolarized smooth muscle cells of the gastric antrum in WT and W/W v mice in a dose-dependent manner. Similarly, the gastric antrum motility in WT mice was significantly increased after treatment with XBF 5 mg (P < 0.05). Atropine (0.1 mg/kg) blocked the enhancement of XBF in WT and W/W v mice completely, while tetrodotoxin (0.05 mg/kg) partially inhibited the enhancement by XBF. CONCLUSION: ICC-IM participates in the regulation of gastric antrum MMC in mice. XBF induces MMC III-like contractions that enhance gastric antrum motility via ICC-IM in mice.

Analysis of Missed Diagnosis of Gastric Lipomas by CT.

INTRODUCTION: Although Computed Tomography (CT) is the most convenient technology for the diagnosis of gastric lipoma, it also has a high rate of missed diagnosis of gastric lipoma. OBJECTIVE: To analyze the causes of missed diagnosis of gastric lipomas by CT. METHODS: We retrospectively studied the CT images and CT diagnosis reports of 25 cases of gastric lipoma confirmed by surgery or clinical follow-up at the Affiliated Hospital of North Sichuan Medical College and Nanchong Central Hospital from 2016 to 2020 and analyzed the causes of missed diagnosis of gastric lipomas. RESULTS: Among the 25 cases of gastric lipomas included in this study, 17 cases (68.0%) were correctly diagnosed by CT, and 8 cases (32.0%) were missed, but there was no case of misdiagnosis. Eighteen cases (72.0%) of gastric lipomas were located in the gastric antrum, 2 cases (8.0%) at the junction of the gastric body and antrum, 5 cases (20.0%) at the fundus of the stomach, 23 cases (92.0%) under the gastric mucosa, and 2 cases (8.0%) under the gastric serous membrane. All gastric lipoma cases were manifested as round or oval-shaped low-density shadows with clear boundaries on CT. 22 cases (88.0%) showed homogeneous low-density shadows while 3 cases (12.0%) mainly showed low-density shadows containing medium-density strips. There was no obvious enhancement in the contrast-enhanced CT scan. The gastric lipoma cases missed by CT were all located under the gastric mucosa of the gastric antrum. When reading the CT images on the default upper abdominal window width and window level, all the missed lesions were similar to the gas image. And the straight meridian of the three lesions was less than 2 cm. CONCLUSION: Fat density shadow in gastric antrum area was mistaken for gastrointestinal gas. Improper CT image window width and window levels and small gastric lipoma volume, along with insufficient knowledge of gastric lipomas imaging by the clinician, might be the main causes of missed diagnosis of gastric lipomas by CT. Familiarity with the CT manifestations of gastric lipomas and rich clinical experience can improve the rate of correct diagnosis of gastric lipomas by CT.

Real-Time Ultrasound Detection of Left Paratracheal Esophagus on Air Entry into the Gastric Antrum in the Induction Period of General Anesthesia: A Prospective, Randomized Study.

BACKGROUND: Positive-pressure ventilation (PPV) delivered via a facemask during anesthesia induction can result in gastric content being inhaled into the lungs. We hypothesized that the real-time ultrasound left paratracheal esophagus monitoring could more effectively reduce air entry into the stomach than real-time ultrasound monitoring of the gastric antrum (GA). METHODS: Patients were divided into two groups: study (S; n=30) and control (C; n=30) groups. During the induction of general anesthesia, mask ventilation adopts a pressure control mode. The initial ventilation pressure of both groups was 15 cmH2O. Before anesthesia induction, an ultrasonic probe was used to monitor the cross-sectional area (CSA) of the GA and the presence of gas in the stomach. During and after anesthesia induction, group S used a high-frequency ultrasound probe to observe the entry of air from the left paratracheal esophagus into the GA. The ventilation pressure was gradually reduced over time until no esophageal air was found. In group C, the ventilatory pressure was set maintained at 15 cmH2O and the CSA of the GA and air intake were monitored using an ultrasonic probe. RESULTS: Before and after PPV, the CSA of the GA in group S decreased (P<0.001), whereas the CSA in group C increased (P=0.002). The GA CSA in group C after PPV was larger than in group S after PPV (P=0.002). The proportion of patients who experienced intragastric air intake in group S (23.3%) was significantly lower than that in group C (66.7) (P=0.001). CONCLUSION: Compared with ultrasound monitoring of the GA, real-time ultrasound detection of LPEOAE into the GA during anesthesia induction was more effective, more sensitive, significantly reduced the prevalence of intragastric air intake, and provided sufficient tidal volume and oxygen for patients.

A novel method of grading gastric intestinal metaplasia based on the combination of subtype and distribution.

BACKGROUND: Studies have shown the value of subtypes and distribution of gastric intestinal metaplasia (GIM) for prediction of gastric cancer. We aim to combine GIM subtypes and distribution to form a new scoring system for GIM. METHODS: This was a cross-sectional study. No GIM, type I, II, and III GIM of gastric antrum and corpus scored 0-3 points respectively. Then the severity of the whole stomach was calculated in two ways: 1. The gastric antrum and corpus scores were added together, with a score ranging from 0 to 6, which named "Subtype Distribution Score of Gastric Intestinal Metaplasia (SDSGIM)". 2. Direct classification according to a table corresponding to that of OLGIM. We compared the SDSGIM among benign lesions, dysplasia, and cancer and drew receiver operating characteristic (ROC) curve to determine the optimal cut-off value. According to the cut-off value and the classification from the table, the predictive ability of these two methods were calculated. RESULTS: 227 patients were included. For SDSGIM, benign lesion group was significantly different from dysplasia or cancer group. Area under curve of ROC curve was 0.889 ± 0.023. The optimal cut-off value was 3. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SDSGIM for malignancy were 89.5%, 78.0%, 74.6%, 91.2% and 82.8%. And those for the second classification method were 84.2%, 82.6%, 77.7%, 87.9%, and 83.3% respectively. CONCLUSIONS: This study firstly combined GIM subtypes with its distribution forming a novel scoring system, which showed high prediction accuracy for malignant lesions.