Baseline Gastric Volume in Fasting Diabetic Patients Is Not Higher than That in Nondiabetic Patients: A Cross-sectional Noninferiority Study.

BACKGROUND: The physiology of diabetes mellitus can increase the risk of perioperative aspiration, but there is limited and contradictory evidence on the incidence of "full stomach" in fasting diabetic patients. The aim of this study is to assess the baseline gastric content (using gastric ultrasound) in diabetic and nondiabetic patients scheduled for elective surgery who have followed standard preoperative fasting instructions. METHODS: This was a prospective, noninferiority study of 180 patients (84 diabetic and 96 nondiabetic patients). Bedside ultrasound was used for qualitative and quantitative assessment of the gastric antrum in the supine and right lateral decubitus positions. Fasting gastric volume was estimated based on the cross-sectional area of the gastric antrum and a validated model. The hypothesis was that diabetic patients would not have a higher baseline fasting gastric volume compared to nondiabetic patients, with a noninferiority margin of 0.4 ml/kg. Secondary aims included the comparison of the incidence of full stomach (solid content or more than 1.5 mL/kg of clear fluid), estimation of the 95th percentile of the gastric volume distribution in both groups, and examination of the association between gastric volume, glycemic control, and diabetic comorbidities. RESULTS: The baseline gastric volume was not higher in diabetic patients (0.81 ± 0.61 ml/kg) compared to nondiabetic patients (0.87 ± 0.53 ml/kg) with a mean difference of -0.07 ml/kg (95% CI, -0.24 to 0.10 ml/kg). A total of 13 (15.5%) diabetic and 11 (11.5%) nondiabetic patients presented more than 1.5 ml/kg of gastric volume (95% CI for difference, -7.1 to 15.2%). There was little correlation between the gastric volume and either the time since diagnosis or HbA1C. CONCLUSIONS: The data suggest that the baseline gastric volume in diabetic patients who have followed standard fasting instructions is not higher than that in nondiabetic patients.

Gastric Volume and Antral Area in the Fasting State: A Meta-analysis of Individual Patient Data.

BACKGROUND: Pulmonary aspiration of gastric content is a serious anesthetic complication. Gastric point-of-care ultrasound can determine the type and volume of gastric content when clinical information is equivocal. However, a cutoff value of either antral cross-sectional area or volume that may be considered as the upper limit of normal in fasting subjects is still controversial. The aim of this study is to characterize the distribution of baseline antral area and volume in fasting adult subjects and to identify an upper limit (95th percentile) of these distributions. METHODS: The authors conducted a meta-analysis of individual participant data of primary studies from an academic research network of investigators collaborating in gastric ultrasound. Studies between January 2009 and December 2020 were included. RESULTS: Twelve primary studies met inclusion criteria and were included in the analysis with a sample size of 1,203 subjects. The 95th percentile of area values (measured in the right lateral decubitus) was 9.9 cm2 (95% CI, 9.4 to 10.4), and of volume, 2.3 ml/kg (95% CI, 2.3 to 2.4). In addition, an antrum grade 0 or 1 indicates a 98% probability of an antral area below the 95th percentile. CONCLUSIONS: An area of 10 cm2 measured in the right lateral decubitus could be a simple, data-driven upper limit of antral area that could serve as a surrogate of upper limit of normal gastric volume values in fasting adults. These results are limited by the highly selected sampling of the studies included.

Evaluation of the 'Sip Til Send' regimen before elective caesarean delivery using bedside gastric ultrasound: A paired cohort pragmatic study.

BACKGROUND: Pre-operative fasting is routinely advocated to avoid pulmonary aspiration. The European Society of Anaesthesiology and Intensive Care (ESAIC) recommends a fasting period of 2 h for liquids before surgery. Liberal drinking policies such as the 'Sip Til Send' are a suggested alternative to maintain hydration before surgery. OBJECTIVES: To compare residual gastric volumes in fully fasted nonlabouring parturients before elective caesarean delivery with the 'Sip Til Send' with water liberal drinking protocol. Our hypothesis was the 'Sip Til Send' would be noninferior to standard fasting at minimising the residual gastric volume immediately before surgery. DESIGN: A paired cohort prospective observational pragmatic study using gastric ultrasound, analysed by an operator blinded to the fasting status of each scan. SETTING: A tertiary maternity hospital in Dublin, Ireland. The study was conducted between January and June 2023. PARTICIPANTS: Pregnant women about to undergo elective caesarean delivery who had followed ESAIC fasting guidelines before admission. INTERVENTIONS: Each participant underwent two pairs (semi-recumbent and the semi-recumbent right lateral positions) of standardised ultrasound examinations of the gastric antrum: the order of these scans was randomised. The first pair of scans occurred on admission before the 'Sip Til Send' protocol commenced, the other pair just before spinal anaesthesia for caesarean delivery, after a variable time following the 'Sip Til Send' protocol. MAIN OUTCOME MEASURE: The primary outcome was the difference in antral cross-sectional area (CSA) between the fully fasted women on admission and the same women after following the 'Sip Til Send' protocol until just before spinal anaesthesia. RESULTS: Fifty-eight women were randomised for the study: 55 and 54 scans in the semi-recumbent position on admission, and 55 and 54 scans in the right lateral position just before spinal anaesthesia. The mean differences (95% CI) in CSA in the semi-recumbent and RL positions were 0.07 (-0.39 to 0.53) cm 2 and 0.04 (-0.60 to 0.68) cm 2 , respectively. Since the of 95% CIs did not cross the predefined noninferiority margin of 0.88 cm 2 , 'Sip Til Send' was noninferior to fully fasting in in terms of the antral CSA. CONCLUSION: The 'Sip Til Send' protocol of liberal hydration with water was noninferior to standard fasting prior to elective caesarean delivery. TRIAL REGISTRY NUMBER: NCT05783427 ClinicalTrials.gov.

Ultrasound Assessment of Gastric Fluid Volume in Children Scheduled for Elective Surgery After Clear Fluid Fasting for 1 Versus 2 Hours: A Randomized Controlled Trial.

BACKGROUND: This study aimed to compare the gastric fluid volume (GFV) in children who fasted 1 versus 2 hours using ultrasound, after ingestion of a defined volume of clear fluid. METHODS: Children scheduled for elective surgery were enrolled in this randomized, double-blinded, controlled trial. After receiving 3 mL kg -1 clear fluid, participants were randomized to have a gastric ultrasound after fasting for either 1 hour (1-hour group, n = 116) or 2 hours (2-hour group, n = 111). Our primary outcome was the GFV. Other outcomes included the antral cross-sectional area, frequency of high risk and low risk of aspiration, and qualitative grading for the gastric antrum. RESULTS: Two hundred and twenty-seven children were available for final analysis. The median (Q1-Q3) GFV was higher in the 1-hour group versus the 2-hour group (0.61 [0.41-0.9] mL kg -1 vs 0.32 [0.23-0.47] mL kg -1 ; P value = .001). None of the study groups had GFV ≥1.5 mL kg -1 . The frequency (%) of GFV ≥1.25 mL kg -1 was comparable between both groups (2 [1.7%] vs 0 [0%], P value = .165). However, the frequency of GFV ≥0.8 mL kg -1 was higher in 1-hour group than in 2-hour group (34.5% vs 4.5%), and grade 2 antral grading score was 56.9% in 1-hour group vs 0.9% in 2-hour group ( P value <.001). CONCLUSIONS: In healthy children scheduled for elective surgery receiving 3 mL kg -1 clear fluid, the median GFV after 1-hour fasting was double the volume after conventional 2-hour fasting. These findings should be considered whether weighting the risk/benefit of a liberal approach to preoperative fasting versus the risk of pulmonary aspiration.

Ultrasound Assessment of Gastric Volume in Parturients After High-Flow Nasal Oxygen Therapy.

BACKGROUND: High-flow nasal oxygen (HFNO) therapy is widely used in critical care obstetrics to improve oxygenation. Much of the benefit of HFNO is linked to the creation of modest levels of positive airway pressure. Pregnant women are generally considered to be at high risk of regurgitation and aspiration. It is unknown whether HFNO may cause gas insufflation into the stomach and further increase this risk. Therefore, this study aimed to systematically evaluate the possible safety effects of HFNO on gastric volume in healthy fasted parturients. METHODS: Sixty fasted parturients scheduled for elective cesarean delivery were enrolled in an observer-blinded, prospective, interventional study. We used ultrasonography to assess changes of antral cross-sectional area (CSA) and gastric volume before and after a 20-minute treatment with HFNO at a rate of 50 L·min -1 . The primary outcome was the change in gastric volume from before to after HFNO therapy, and the secondary outcome was the distribution of antral grades. RESULTS: In semirecumbent right lateral position, the antral CSA at baseline and after treatment with HFNO was 3.81 (3.01-4.72) cm 2 and 3.79 (3.03-4.54) cm 2 , respectively. The estimated fluid volume at baseline and after treatment with HFNO was 38.51 (33.39-54.62) mL and 39.71 (32.00-52.82) mL, respectively. All participants had either a grade 0 or grade 1 antrum, and most of them had a grade 0 antrum. There was no significant difference in gastric volume and distribution of antral grades before and after HFNO therapy. Gastric air distension was not shown in any of the parturients either at baseline or after treatment with HFNO. CONCLUSIONS: Treatment with HFNO for 20 minutes at flow rates up to 50 L·min -1 did not increase gastric volume in term pregnant women breathing spontaneously when evaluated by gastric ultrasonography.

The correlation between patient satiety sensation and total gastric fluid volume: a prospective observational study.

PURPOSE: Surgical patients are asked to adhere to preoperative fasting guidelines to minimize gastric contents. Large fluid volumes or solid content can still be present as shown with gastric ultrasound. It has been suggested that additional rating of patients' satiety, measured as the feeling of hunger and thirst, could help clinicians to better judge emptying of the stomach. METHODS: We performed a prospective observational study in fasted elective surgical patients. The primary objective was to investigate the correlation between hunger measured on a 0-10 numeric rating scale and total gastric fluid volume measured with gastric ultrasonography. Secondary objectives included the correlation between 1) thirst and total gastric fluid volume and 2) hunger, thirst, and the Perlas grading scale score. RESULTS: We included 515 patients. The exam was inconclusive in 14 individuals (2.7%). The Spearman correlation coefficient between gastric fluid volumes and hunger was 0.11 (95% confidence interval [CI], 0.02 to 0.20) (P = 0.01). The correlation between gastric fluid volumes and thirst was 0.11 (95% CI, 0.02 to 0.20) (P = 0.02). Between antral grades and numeric rating scale, the correlation coefficient was 0.00 (95% CI, -0.09 to 0.09) (P = 1.00) for thirst and 0.00 (95% CI, -0.08 to 0.09) (P = 0.94) for hunger. Ten patients (2.0%) had solid content, 24 presented a grade 2 antrum (4.8%). CONCLUSION: This study suggests that the correlation between total gastric fluid volume and satiety sensation is very weak. Satiety did not reliably predict total gastric fluid volume. STUDY REGISTRATION: ClinicalTrials.gov (NCT04884373); registered 13 May 2021.

RéSUMé: OBJECTIF: On demande aux patient·es de chirurgie de respecter les directives de jeûne préopératoire afin de minimiser leur contenu gastrique. Comme le montre l'échographie gastrique, de grands volumes de liquide ou des solides peuvent encore être présents. Il a été suggéré qu'une évaluation supplémentaire de la satiété des patient·es, mesurée par la sensation de faim et de soif, pourrait aider les clinicien·nes à mieux estimer la vidange de l'estomac. MéTHODE: Nous avons réalisé une étude observationnelle prospective chez des patient·es de chirurgie non urgente à jeun. L'objectif principal était d'étudier la corrélation entre la faim mesurée sur une échelle d'évaluation numérique de 0 à 10 et le volume total de liquide gastrique mesuré par échographie gastrique. Les objectifs secondaires comprenaient la corrélation entre 1) la soif et le volume total de liquide gastrique et 2) la faim, la soif et le score de l'échelle de classement Perlas. RéSULTATS: Nous avons inclus 515 personnes. L'examen était non concluant chez 14 individus (2,7 %). Le coefficient de corrélation de Spearman entre les volumes de liquide gastrique et la faim était de 0,11 (intervalle de confiance [IC] à 95 %, 0,02 à 0,20) (P = 0,01). La corrélation entre les volumes de liquide gastrique et la soif était de 0,11 (IC 95 %, 0,02 à 0,20) (P = 0,02). Entre les grades antraux et l'échelle d'évaluation numérique, le coefficient de corrélation était de 0,00 (IC 95 %, -0,09 à 0,09) (P = 1,00) pour la soif et de 0,00 (IC 95 %, -0,08 à 0,09) (P = 0,94) pour la faim. Un contenu solide a été observé chez dix personnes (2,0 %), et 24 présentaient un antre de grade 2 (4,8 %). CONCLUSION: Cette étude suggère que la corrélation entre le volume total de liquide gastrique et la sensation de satiété est très faible. La satiété n'a pas permis de prédire de manière fiable le volume total de liquide gastrique. ENREGISTREMENT DE L'éTUDE: clinicaltrials.gov (NCT04884373); enregistrée le 13 mai 2021.

Ultrasound assessment of gastric residual volume in patients over 60 years of age undergoing gastroscopy under sedation: a prospective cohort study.

BACKGROUND: We aimed to assess the accuracy of ultrasonographic measurement of the antral cross-sectional area (CSA) in the preprocedural evaluation of gastric contents and volume in fasted patients > 60 yr of age scheduled for gastroscopy under sedation. METHODS: We included n = 81 patients > 60 yr of age and n = 79 younger controls scheduled to undergo elective gastroscopy in a prospective cohort study. A gastric ultrasound examination was performed to measure the antral CSA in both semisitting and right lateral decubitus (RLD) positions. Afterward, patients were graded using the Perlas qualitative grading scale. The actual gastric volume was endoscopically suctioned. Full stomach was defined as gastric volume > 1.5 mL·kg-1 and/or the presence of solid particles. We constructed receiver operating characteristic curves to determine the accuracy of ultrasonographic measurement of RLD CSA to detect a gastric volume > 1.5 mL·kg-1 and calculated the diagnostic test attributes of RLD CSA for the identification of a gastric volume > 1.5 mL·kg-1 RESULTS: The incidence of full stomach was 8/81 (9.8%) in patients > 60 yr of age and 1/79 (1.2%) in young patients (risk difference, 8.6%; 95% CI, 1.3 to 15.8; P = 0.03). The cut-off value of RLD CSA was 10.4 cm2 for the detection of gastric volume > 1.5 mL·kg-1 in patients > 60 yr of age, with a sensitivity of 75%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 98.6%. CONCLUSION: Patients > 60 yr of age scheduled for gastroscopy under sedation had a higher incidence of a full stomach detected with ultrasound compared with a younger cohort, which is potentially associated with a higher aspiration risk. We calculated a cut-off value of RLD CSA for detecting gastric volume in patients > 60 yr of age of approximately 10 cm2, which may help to quickly assess patients at risk of aspiration. TRIAL REGISTRATION: www.chictr.org.cn (ChiCTR2100048994); registered 19 July 2021.

RéSUMé: CONTEXTE: Notre objectif était d'évaluer la précision de la mesure échographique de la section transversale antrale (CSA) dans l'évaluation préprocédurale du contenu et du volume gastriques chez les patient·es à jeun > 60 ans devant bénéficier d'une gastroscopie sous sédation. MéTHODE: Nous avons inclus n = 81 patient·es > 60 ans et n = 79 patient·es témoins plus jeunes devant bénéficier d'une gastroscopie non urgente dans une étude de cohorte prospective. Une échographie gastrique a été réalisée pour mesurer la CSA antrale en position semi-assise et en décubitus latéral droit (DLD). Par la suite, la patientèle a été classée à l'aide de l'échelle de classement qualitatif de Perlas. Le volume gastrique réel était aspiré par endoscopie. Un estomac plein a été défini comme un volume gastrique > 1,5 mL·kg­1 et/ou la présence de particules solides. Nous avons construit des courbes de la fonction d'efficacité du récepteur (courbes ROC) afin de déterminer la précision de la mesure échographique de la CSA en DLD pour détecter un volume gastrique > 1,5 mL·kg­1 et calculé les attributs du test diagnostique de la CSA en DLD pour identifier un volume gastrique > 1,5 mL·kg­1. RéSULTATS: L'incidence d'estomac plein était de 8/81 (9,8 %) chez les patient·es > 60 ans et 1/79 (1,2 %) chez les patient·es jeunes (différence de risque, 8,6 %; IC 95 %, 1,3 à 15,8; P = 0,03). La valeur seuil de la CSA en DLD était de 10,4 cm2 pour la détection d'un volume gastrique > 1,5 mL·kg­1 chez la patientèle > 60 ans, avec une sensibilité de 75 %, une spécificité de 100 %, une valeur prédictive positive de 100 % et une valeur prédictive négative de 98,6 %. CONCLUSION: La patientèle > 60 ans devant bénéficier d'une gastroscopie sous sédation avait une incidence plus élevée d'estomac plein détecté par échographie par rapport à une cohorte plus jeune, ce qui est potentiellement associé à un risque d'aspiration plus élevé. Nous avons calculé une valeur seuil de la CSA en DLD pour détecter le volume gastrique chez les patient·es > 60 ans d'environ 10 cm2, ce qui peut aider à évaluer rapidement les personnes à risque d'aspiration. ENREGISTREMENT DE L'éTUDE: www.chictr.org.cn (ChiCTR2100048994); enregistrée le 19 juillet 2021.

An unusual cause of a protuberant lesion of the gastric antrum.

A 58-year-old man presented to our hospital due to upper abdominal pain for 2 months. Gastroscopy showed a 1.5×1.5×1 cm3 protuberant lesion in the gastric antrum. Magnifying endoscopy with blue laser imaging showed roughly normal micro-surface and micro-vessel structure. Endoscopic ultrasonography showed the lesion originated from the muscularis propria, with low-density irregular cystic echo. Then the patient received treatment of gastrointestinal lesions with endoscopic submucosal dissection. During the operation, it could be seen that the lesion was mainly located in the submucosa, the local depth of which reached the muscularis mucosae. It was tan-white in color, with toughness and cystic tactile sensation. The operation went smoothly and his recovery was good. Pathological studies showed that pancreatic tissue was found in the lesion, which was composed of exocrine acini and ducts. Meanwhile, dilated cystic glands were found in the excised specimens. He was eventually diagnosed as ectopic pancreas in gastric antrum complicated with gastritis cystica profunda (GCP).

Ultrasound assessment of gastric contents in children before general anaesthesia for acute appendicitis.

There is increasing evidence that a minority of adults with acute appendicitis have gastric contents, posing an increased risk of pulmonary aspiration. This study aimed to evaluate the proportion of children with acute appendicitis who have gastric contents considered to pose a higher risk of pulmonary aspiration. We analysed point-of-care gastric ultrasound data routinely collected in children before emergency appendicectomy in a specialist paediatric hospital over a 30-month period. Based on qualitative and quantitative antral assessment in the supine and right lateral decubitus positions, gastric contents were classified as 'higher-risk' (clear liquid with calculated gastric fluid volume > 0.8 ml.kg-1 , thick liquid or solid) or 'lower-risk' of pulmonary aspiration. The 115 children studied had a mean (SD) age of 11 (3) years; 37 (32%; 95%CI: 24-42%) presented with higher-risk gastric contents, including 15 (13%; 95%CI: 8-21%) with solid/thick liquid contents. Gastric contents could not be determined in 13 children as ultrasound examination was not feasible in the right lateral decubitus position. No cases of pulmonary aspiration occurred. This study shows that gastric ultrasound is feasible in children before emergency appendicectomy. This technique showed a range of gastric content measurements, which could contribute towards defining the risk of pulmonary aspiration.

Effect of a carbohydrnate lollipop on the gastric volume of fasted pediatric patients.

BACKGROUND: Preoperative fasting is part of routine practice. Children subjected to prolonged preoperative fasting often suffer adverse effects. Consuming a preoperative lollipop may lessen their anxiety and have clinical benefits. AIMS: To assess the effect of consuming a lollipop on gastric volume and the feasibility of administering a lollipop to a child preoperatively. METHODS: In this prospective, repeated measures interventional study, we measured gastric antrum volume using ultrasound in children aged 2-18 years. We measured antrum volumes after participants had fasted for a minimum of 6 h for solids and 2 h for clear fluids. They then consumed a standard carbohydrate lollipop, and we repeated the antrum volume measurements after 1 h. RESULTS: Of the 38 patients enrolled, 32 completed the study; four had ingested additional food or liquid, and two were diagnosed with systemic disease the day after data collection. The gastric volume data were normally distributed. The mean volume change was 0.01 ml kg-1 (95% CI -0.02 to 0.05; p = .460). The mean postlollipop volume was 0.51 ml kg-1 (95% CI 0.43 to 0.58). CONCLUSIONS: Consuming a standard lollipop did not affect the gastric volume of fasted pediatric patients.

Evaluation of gastric contents using ultrasound in full-term pregnant women fasted for 8 h: a prospective observational study.

BACKGROUND: We aimed to evaluate the gastric volume and contents after an 8-h fasting period in full-term, non-laboring, pregnant women following a standardized meal. METHODS: In this prospective observational study, we included full-term pregnant women scheduled for elective cesarean delivery. The participants were instructed to fast after a standardized meal (apple juice, bread, and cheese). Participants were scanned in the semi-recumbent and right-lateral positions 8 h after the standardized meal. The primary outcome was the proportion of patients with gastric volume > 1.5 mL kg-1 calculated by two equations. Secondary outcomes included the antral cross-sectional area and gastric volume. Data are expressed as frequency (%, 95% confidence interval [CI]), mean ± standard deviation (95% CI of the mean), or median (quartiles) as appropriate. RESULTS: Forty-one women were available for the final analysis. For the primary outcome, one participant (2.4%, 95% CI of 0.06 to 12.8%) had gastric volume > 1.5 mL kg-1, and none had solids in the antrum. For the secondary outcomes, the mean (95% CI of the mean) of the antral cross-sectional area was 2.11 ± 0.72 (1.88 to 2.34) cm2 and 4.08 ± 1.80 (3.51 to 4.65) cm2 during the semi-recumbent and right-lateral position, respectively. The median (quartiles) gastric volume was 0.53 (0.32, 0.66) mL kg-1 and 0.33 (0.13, 0.52) mL kg-1 as estimated by Perlas et al. and Roukhomovsky et al. equations, respectively. CONCLUSION: After 8-h fasting following a standardized meal, full-term pregnant non-laboring women are less likely to have a high residual gastric volume.

Routine point-of-care ultrasound (POCUS) assessment of gastric antral content in traumatic emergency surgical patients for prevention of aspiration pneumonitis: an observational clinical trial.

BACKGROUND: Polytrauma patients are at a higher risk of delayed gastric emptying. To assess the gastric volume, a reliable diagnostic tool is needed to prevent the occurrence of aspiration pneumonia, which remains a serious complication associated with anesthesia. Gastric antral ultrasound can provide reliable information about the size of the gastric antrum in traumatized patients undergoing emergency surgery. METHODS: A prospective observational study of 45 polytrauma patients undergoing emergency surgery under general anesthesia was carried out. Prior to induction of anesthesia in the emergency department, gastric ultrasound was performed for qualitative and quantitative assessment of the gastric antrum in a supine position and right lateral decubitus (RLD) position. This was followed by routine placement of the nasogastric tube to aspirate and calculate the volume of the stomach contents. RESULTS: Of the 45 polytrauma patients, the risk assessment of aspiration and the anesthesia technique changed in 14 patients (31.1%) after the gastric ultrasound examination. A very good relationship existed between the expected stomach volume at the RLD position and the suction volume in the nasogastric tube. In all cases, no aspirations were documented. CONCLUSION: Ultrasound examination of the stomach in polytrauma patients allows assessing the size and type of stomach contents. The data obtained can influence the choice of anesthesia technique and reduce the risk of aspiration pneumonia. TRIAL REGISTRATION: This trial was registered at ClinicalTrials.gov . registry number: NCT04083677 on September 6, 2019.

Complete resection of the gastric antrum decreased incidence and severity of delayed gastric emptying after pancreaticoduodenectomy.

BACKGROUND: Delayed gastric emptying (DGE) is the main complication after pancreaticoduodenectomy (PD), but the mechanism is still unclear. The aim of this study was to elucidate the role of complete resection of the gastric antrum in decreasing incidence and severity of DGE after PD. METHODS: Sprague-Dawley rats were divided into three groups: expanded resection (ER group), complete resection (CR group), and incomplete resection (IR group) of the gastric antrum. The tension (g) of remnant stomach contraction was observed. We analyzed the histological morphology of the gastric wall by different excisional methods after distal gastrectomy. Moreover, patients underwent PD at our department between January 2012 and May 2016 were included in the study. These cases were divided into IR group and CR group of the gastric antrum, and the clinical data were retrospectively analyzed. RESULTS: The ex vivo remnant stomachs of CR group exhibited much greater contraction tension than others (P < 0.05). The contraction tension of the remnant stomach increased with increasing acetylcholine concentration, while remained stable at the concentration of 10 × 10-5 mol/L. Furthermore, 174 consecutive patients were included and retrospectively analyzed in the study. The incidence of DGE was significantly lower (3.5% vs. 21.3%, P < 0.01) in CR group than in IR group. In addition, hematoxylin-eosin staining analyses of the gastric wall confirmed that the number of transected circular smooth muscle bundles were higher in IR group than in CR group (8.24 ± 0.65 vs. 3.76 ± 0.70, P < 0.05). CONCLUSIONS: The complete resection of the gastric antrum is associated with decreased incidence and severity of DGE after PD. Gastric electrophysiological and physiopathological disorders caused by damage to gastric smooth muscles might be the mechanism underlying DGE.

Does ultrasonographic assessment of gastric antrum correlate with gastric residual volume in critically ill patients? A prospective observational study.

This study aimed to evaluate the relationship between ultrasonographic gastric antral measurements and aspirated gastric residual volume (GRV) in mechanically ventilated critically ill patients receiving enteral nutrition (EN). This prospective observational study included 56 enterally-fed critically ill patients in one-year period. All imaging procedures were done at 30-degree head-of-bed elevation and supine position on epigastric region of abdomen with 2.5-6 MHz convex-array probe just before routine GRV aspiration. The antral cross-sectional area (CSA) was calculated by measuring the anteroposterior (dAP) and craniocaudal diameters (dCC) of the gastric antrum. Total 283 ultrasonographic gastric antrum imaging procedures were done. In only eight (2.82%) attempts, the antrum could not be visualized due to inhibition from intra-gastric air or gas in the surrounding intestinal lumen. The calculated mean antral CSA was 568.15 ± 348.37 mm2 (103.43-2,846.30). The antral CSA correlated significantly with aspirated GRV, and the antral CSA increased linearly with increasing aspirated GRV (R2 = 0.73, p < 0.0001). In Receiver operating characteristic (ROC) analysis of antral CSA ≥ 920 mm2 (mean + 1*SD) for estimating aspirated GRV, the area under the curve (AUC) was 0.848 (95% CI, 0.76 ~ 0.93) (p < 0.0001), and ROC analysis of antral CSA to discriminate aspirated GRV ≥ 250 mL showed a significant relation (AUC = 0.969, 95% CI 0.94 ~ 0.99, p < 0.0001). Ultrasonographic measurement of gastric antral CSA is an easy and reliable bedside procedure to estimate GRV in critically ill patients receiving EN in 30-degree head-of-bed elevation and supine position. Trial registration number: NCT04413474, date of registration: June 17, 2020, retrospectively registered.

Using gastric emptying scintigraphy to evaluate antral contractions and duodenal bolus propagation.

Our aim was to investigate the feasibility of measuring antral contractions and duodenal bolus propagation (DBP) during dynamic antral contraction scintigraphy (DACS) as an assessment of antro-pyloro-duodenal coordination (APDC). Gastric emptying scintigraphy (GES) with DACS was performed with Tc-99m sulfur colloid (SC) using increasing doses of 74 MBq (2 mCi) for 10 subjects, 185 MBq (5 mCi) for 11, and 370 MBq (10 mCi) for 11. DACS was performed for 10 min after static images at 0, 30, 60, 120, 180, and 240 min in anterior and right anterior oblique (RAO) projections. Best projection and lowest dose of Tc-99m SC were assessed visually. DBP were quantified utilizing duodenal activity peaks from a region of interest in the first portion of the duodenum. DBP was better visualized in the RAO projection than anterior projection and using 185 MBq (5 mCi) and 370 MBq (10 mCi) compared with 74 MBq (2 mCi). DBP showed infrequent and irregular bolus transfers from the antrum to the duodenum. Antral activity peaks at 60 min averaged 2.91 ± 0.66 per minute and duodenum bolus peaks 0.36 ± 0.18 per minute (ratio 0.36/2.91 = 0.12). DBP activity peaks can be measured during GES with DACS but requires a 185-MBq (5 mCi) dose of Tc-99m SC radiolabeled test meal for adequate DBP signal detection and is better imaged in RAO than anterior projection. DBPs over the first 60 min postmeal ingestion are infrequent with only 12% of the antral contractions propagating into the duodenum. This methodology appears promising to assess APDC.NEW & NOTEWORTHY This study shows that duodenal bolus propagations after meal ingestion can be measured during gastric emptying scintigraphy using dynamic scintigraphy. Duodenal bolus propagation over the first 60 min postmeal ingestion are infrequent with only 12% of the antral contractions propagating into the duodenum. This methodology appears promising to assess antropyloroduodenal coordination in patients with unexplained symptoms of upper gastrointestinal dysmotility.

Ultrasound assessment of gastric content in fasted patients before elective laparoscopic cholecystectomy: a prospective observational single-cohort study.

BACKGROUND: Patients with symptomatic gallbladder diseases exhibit delayed gastric emptying. We evaluated the residual gastric content in fasted patients scheduled for elective laparoscopic cholecystectomy because of symptomatic gallbladder disease using ultrasonography. METHODS: This prospective observational single-cohort study was approved by the Institutional Review Board, and written informed consent was obtained from all included patients. Before anesthesia induction, the gastric antrum was examined by ultrasound. Once the presence of solid content was excluded, the patients were classified using a three-point grading system (grade 0: no fluid; grade 1: fluid in the right lateral decubitus position; grade 2: fluid in both the supine and right lateral decubitus positions), and the fluid volume was measured. A stomach was considered empty if it had no contents or ≤ 1.5 mL·kg-1 of fluid, and was considered full if solid content or > 1.5 mL·kg-1 of fluid was detected. RESULTS: Among 138 patients, 18 patients (13%) presented with a full stomach, 12 (9%) of whom had solid content, and six (4%) of whom had >1.5 mL·kg-1 of fluid in their stomach. Among the remaining 120 patients with an empty stomach, 65 patients presented with a grade 0 antrum, and 55 patients with a grade 1 or 2 antrum with ≤ 1.5 mL·kg-1 of fluid. CONCLUSION: The gastric ultrasound assessment revealed that 13% of patients scheduled for elective cholecystectomy because of symptomatic gallbladder disease had a full stomach despite following the fasting guidelines. This was higher than the reported incidence of a full stomach among the general surgical population. Further studies are required to delineate the clinical implications of our findings. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT03259841); registered 4 August, 2017.

RéSUMé: CONTEXTE: Les patients atteints de maladies vésiculaires symptomatiques souffrent de retard de la vidange gastrique. Nous avons évalué par échographie le contenu gastrique résiduel chez des patients à jeun devant subir une cholécystectomie non urgente par laparoscopie en raison de maladie vésiculaire symptomatique. MéTHODE: Cette étude prospective observationnelle sur une cohorte unique a été approuvée par le Comité d'éthique indépendant et le consentement éclairé écrit a été obtenu de tous les patients inclus. Avant l'induction de l'anesthésie, l'antre gastrique a été examiné par échographie. Une fois la présence de solides exclue, les patients ont été catégorisés selon un système de notation de 3 grades (0 : aucun liquide; 1 : liquides détectés en position de décubitus latéral droit; 2 : liquides détectés en décubitus dorsal et en décubitus latéral droit), et le volume liquidien a été mesuré. Un estomac était considéré comme vide s'il n'avait aucun contenu solide et ≤ 1,5 mL·kg−1 de liquides, et considéré comme plein si du contenu solide ou > 1,5 mL·kg−1 de liquides était détecté. RéSULTATS: Parmi 138 patients, 18 (13 %) se sont présentés avec un estomac plein, parmi lesquels 12 (9 %) avaient du contenu solide, et six (4 %) avaient > 1,5 mL·kg−1 de liquides dans l'estomac. Parmi les 120 patients restants avec un estomac vide, 65 présentaient un antre gastrique de grade 0 et 55 présentaient un antre de grade 1 ou 2 avec ≤ 1,5 mL·kg−1 de liquides. CONCLUSION: L'évaluation gastrique par échographie a révélé que 13 % des patients devant subir une cholécystectomie non urgente en raison de maladie vésiculaire symptomatique avaient un estomac plein tout en ayant respecté les directives de jeûne. Ce chiffre était plus élevé que l'incidence rapportée d'estomac plein parmi la population chirurgicale générale. Des études supplémentaires sont nécessaires pour déterminer les implications cliniques de nos résultats. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT03259841); enregistrée le 4 août 2017.

A clinical study comparing ultrasound-measured pyloric antrum cross-sectional area to computed tomography-measured gastric content volume to detect high-risk stomach in supine patients undergoing emergency abdominal surgery.

The main aim of this study was to assess whether the ultrasound examination and measurement of the pyloric antral cross-sectional area (antral-CSA) in the supine position could be useful to diagnose a full stomach using a computed tomography (CT) as a comparator in emergency patients. Immediately before general anesthesia induction in patients undergoing emergency abdominal surgery, antral-CSA was measured and the volume of the gastric contents was evaluated via ultrasound in the supine position. Gastric content volume was also calculated from a CT image taken prior to the operation. The primary outcome of this study was to determine the antral-CSA threshold of the "high-risk stomach" defined as the presence of solid/thick fluid and/or gastric content volume > 1.5 mL/kg. The secondary outcome was to evaluate the correlation between gastric content volume calculated by CT and antral-CSA. Thirty-nine patients provided consent and were included. Ten patients had gastric contents over 1.5 mL/kg, and 18 patients showed solid contents/thick fluids. The median [IQR] antral-CSA and gastric content volume were 3.82 [2.74-5.07] cm2 and 0.32 [0.09-2.08] mL/kg, respectively. The antral-CSA cutoff value of "high-risk stomach" was 3.01 cm2. This value had a sensitivity of 85%, a negative predictive value of 53%, and AUC of the ROC of 0.670 (p = 0.03). The Spearman rank-order correlation between both measures was 0.420 (p = 0.01). The correlation was improved, particularly in stomachs with solid contents/thick fluids. Antral-CSA measured in the supine position may help to assess the high-risk stomach patients undergoing emergency surgery.Trial registration: www.umin.ac.jp (UMIN 000013416). Registered 14 March 2014.

Term pregnant patients have similar gastric volume to non-pregnant females: a single-centre cohort study.

BACKGROUND: The physiological changes of pregnancy can increase the risk of peri-partum pulmonary aspiration. There is limited objective information regarding gastric volumes in pregnant patients. The aim of this cohort study was to characterise prospectively the range of gastric-fluid volume in term non-labouring pregnant patients compared with a historical cohort of non-pregnant females. METHODS: Fasted non-labouring term pregnant patients scheduled for elective Caesarean delivery underwent a standardised gastric ultrasound examination. Gastric content was evaluated qualitatively (type of content), semi-quantitatively (Perlas grades), and quantitatively (volume). The antral cross-sectional area and volume were compared with those of a retrospective cohort of non-pregnant females from the same institution. Descriptive statistics were used to describe the central tendency through mean and median values. Dispersion was evaluated with standard deviation and inter-quartile range, and the higher end of the distribution as 95th percentile. RESULTS: Non-labouring pregnant (59) and non-pregnant (81) subjects were studied. The range of estimated total gastric-fluid volume (P=0.96) and volume per body weight (P=0.78) was not significantly different between cohorts. An estimated volume of 115 ml (102-143) vs 136 ml (106-149) and volume per body weight of 1.4 ml kg-1 (1.2-2.8) vs 2.0 ml kg-1 (1.5-2.7) corresponded to the 95th percentile (95% confidence interval) values in the pregnant and non-pregnant cohort, respectively. CONCLUSIONS: Baseline gastric volume of non-labouring pregnant patients at term is not significantly different from that of non-pregnant females. This information will be helpful to interpreting findings of gastric point-of-care ultrasound in obstetric patients.

Diagnosis and treatment of gastric antral webs in pediatric patients.

BACKGROUND: Gastric antral webs are mucosal structures, varying from fenestrated diaphragms to mucosal crescents, resulting in varying degrees of foregut obstruction. Patients commonly present with vomiting, failure to thrive, and abdominal pain. Prevalence is unknown, and diagnosis can be difficult. METHODS: We performed an IRB-approved retrospective review of patients from 4/1/2015-4/1/2018 at a Level I Children's Surgery Center undergoing gastric antral web resection. Data obtained included demographics, preoperative workup, surgical repair, and outcomes. RESULTS: Twenty-one patients were identified; 67% were male with an average age of 30 months at diagnosis. Initial diagnosis was established by a combination of fluoroscopy and esophagogastroduodenoscopy (EGD) in all patients. Patients presented with emesis (76%), failure to thrive (57%), need for post-pyloric tube feeds (33%), and abdominal pain (14%). Web localization without intraoperative EGD (n = 3) was initially challenging. As a result, intraoperative EGD was combined with operative antral web resection to facilitate web localization (n = 18). Web marking techniques have evolved from marking with suture (n = 1) and tattoo (n = 2), to endoscopic clip application (n = 12). All 21 patients underwent web resection, 2 were performed laparoscopically. Twenty underwent Heineke-Mikulicz pyloroplasty during the initial surgery. Average length of stay was 5.5 days. There were no intraoperative complications or deaths. Permanent symptom resolution occurred in 90% of patients immediately, with a statistically significant decrease in emesis (p < 0.001), failure to thrive (p < 0.001), and need for post-pyloric tube feeding (p = 0.009) within 6 months of surgery. CONCLUSION: Gastric antral webs should be considered in the differential diagnosis for a child with persistent vomiting. Web resection with the use of intraoperative endoscopic localization can result in permanent symptom resolution in the majority of these patients.