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.

Ultrasonographic evaluation of gastric content and volume: a systematic review

SUMMARY OBJECTIVE: Bronchoaspiration of gastric content is associated with high morbidity and mortality, but evaluating this complication is a difficult task. However, gastric ultrasonography can safely assess gastric content and prevent bronchoaspiration. Therefore, a systematic review was performed in order to verify the efficacy of ultrasonography in the qualitative and quantitative analyses of gastric content. METHODS: A literature review of articles published between 2009 and 2019 in the PubMed and LILACS databases was conducted using combinations of the keywords "gastric ultrasound," "gastric emptying," and "gastric content." RESULTS: Of the 20 articles found, 19 chose the antral region as the best site for qualitative analysis of the gastric content. Regarding quantitative measurement, the most commonly used method to calculate the gastric volume in eight articles was the formula "Gastric Volume = 27 + (14.6 × ATAG) − (1.28 × Age)," in which the area of the transverse section of the gastric antrum (ATAG) could also be calculated by the largest antral diameters or by free tracing. CONCLUSION: An efficient evaluation of the gastric content can be performed by ultrasonography of the antral region, contributing to greater safety in the clinical management of patients with increased risk for bronchoaspiration during airway management.

RESUMO OBJETIVO: A broncoaspiração do conteúdo gástrico associa-se à alta morbimortalidade, porem a avaliação desta complicação é tarefa dificil. Por outro lado, a ultrassonografia gástrica avalia o conteúdo gástrico com segurança, podendo evitar a broncoaspiração. Portanto, foi realizada revisão sistemática com objetivo de verificar a aplicabilidade da ultrassonografia na análise qualitativa e quantitativa do conteúdo gástrico. MÉTODOS: Revisão de literatura de artigos publicados entre 2009 e 2019 nas bases de dados PubMed e LILACS usando combinações das palavras chave: "Gastric ultrasound", "gastric emptying" e "gastric content". RESULTADOS: Foram encontrados 20 artigos. A região antral foi escolhida em 19 artigos como melhor local do ponto de vista qualitativo para analisar o conteúdo gástrico. A respeito da mensuração quantitativa, o método mais utilizado para cálculo do volume gástrico, escolhido em 8 artigos, foi através da fórmula Volume gástrico = 27 + (14,6 x ATAG) - (1,28 x Idade), em que a Área da Secção Transversa do Antro Gástrico (ATAG) pode ser igualmente calculada pelos maiores diâmetros antrais ou pelo seu traçado livre. CONCLUSÃO: A ultrassonografia da região antral permite boa avaliação do conteúdo gástrico, trazendo maior segurança ao manejo clínico de pacientess com risco aumentado para broncoaspiração no manejo da via aerea.

Ultrasound assessment of gastric antrum in term pregnant women before elective cesarean section / Ultrassom de antro gástrico em gestantes a termo antes de cesariana eletiva

Abstract Background and objectives: Pregnant women are considered patients at risk for pulmonary aspiration of gastric contents. The study aim was to evaluate the gastric antral cross-sectional area using ultrasound. Method: In this prospective study, 85 scheduled term pregnant women underwent gastric ultrasound. The outcomes were the measurement of the gastric antral cross-sectional area (main outcome), the estimated gastric volume, the incidence of pregnant women at risk for pulmonary aspiration, and the association between gastric antral cross-sectional area and clinical-demographic characteristics. Gastric antral cross-sectional area and gastric volume were compared according to body mass index <30 or ≥30. Results: The median (IIQ) for gastric antral cross-sectional area was 4 cm2 (2.8-6.3), for the estimated gastric volume it was 49.8 mL (33.7-87.2), and for the gastric volume estimated in mL.kg-1 it was 0.62 mL.kg-1 (0.39-0.95). The 95th percentile [95% confidence interval (CI)] of the gastric antral cross-sectional area and the estimated gastric volume were ≤10.3 cm2 (95% CI: 7.6-15.6) and 1.42 mL.kg-1 (95% CI: 1.20-2.64), respectively. The incidence of pregnant women at risk for pulmonary aspiration was 3.5% (CI: 3.5 (1.2-9.8)). There was a positive correlation between gastric antral cross-sectional area and weight, p < 0.001 and body mass index <0.001. Patients with a body mass index ≥30 had a gastric antral cross-sectional area and an estimated gastric volume greater than those with a body mass index <30, respectively, p < 0.01 and p < 0.02. Conclusion: Measuring the gastric antral cross-sectional area of pregnant women is feasible and easy. There was positive correlation between gastric antral cross-sectional area, body weight and body mass index. The estimation of gastric volume by measuring the gastric antral cross-sectional area can identify patients at risk for pulmonary aspiration. Obese patients had a gastric antral cross-sectional area and an estimated gastric volume greater than non-obese patients.

Resumo Justificativa e objetivos: As gestantes são consideradas pacientes de risco para aspiração pulmonar do conteúdo gástrico. O objetivo foi avaliar a área transversal do antro gástrico por meio de ultrassonografia. Método: Neste estudo prospectivo, 85 gestantes a termo agendadas foram submetidas à ultrassonografia do antro gástrico. Os desfechos foram a mensuração da área transversal do antro gástrico (desfecho principal), a estimativa do volume gástrico, a incidência de gestantes sob risco de aspiração pulmonar, a associação entre a área transversal do antro gástrico e características clínico-demográficas. A área transversal do antro gástrico e do volume gástrico foi comparada de acordo com o índice de massa corporal < 30 ou ≥ 30. Resultados: A mediana (IIQ) da área transversal do antro gástrico foi 4 cm2 (2,8-6,3), do volume gástrico estimado 49,8 mL (33,7-87,2) e do volume gástrico estimado em mL.kg-1 de 0,62 mL.kg-1 (0,39-0,95). O percentil 95 [intervalo de confiança (IC) 95%] da área transversal do antro gástrico e do volume gástrico estimado foi ≤ 10,3 cm2 (IC 95%: 7,6-15,6) e 1,42 mL.kg-1 (IC 95%: 1,20-2,64), respectivamente. A incidência de gestantes sob risco de aspiração pulmonar foi de 3,5% (IC: 3,5 (1,2-9,8). Houve correlação positiva entre a área transversal do antro gástrico e peso, p < 0,001 e índice de massa corporal p < 0,001. As pacientes com índice de massa corporal ≥ 30 apresentaram maior área transversal do antro gástrico, e do volume gástrico estimado, do que as com índice de massa corporal < 30, respectivamente p < 0,01 e p < 0,02. Conclusão: A mensuração da área transversal do antro gástrico de gestantes é factível e fácil. A área transversal do antro gástrico correlacionou-se positivamente com peso e índice de massa corporal. A estimativa do volume gástrico através da mensuração da área transversal do antro gástrico pode identificar pacientes sob risco de aspiração pulmonar. As pacientes obesas apresentaram área transversal do antro gástrico e volume gástrico estimado maior do que as não obesas.

Qualitative and quantitative ultrasound assessment of gastric content / Avaliação qualitativa e quantitativa do conteúdo gástrico através da ultrassonografia

Summary Objective: Pulmonary aspiration of the gastric contents is one of the most feared complications in anesthesia. Its prevention depends on preoperative fasting as well as identification of risky patients. A reliable diagnostic tool to assess gastric volume is currently lacking. The aim of this study performed on volunteers was to evaluate the feasibility of ultrasonography to identify qualitative and quantitative gastric content. Method: A standardized gastric scanning protocol was applied on 67 healthy volunteers to assess the gastric antrum in four different situations: fasting, after ingesting clear fluid, milk and a solid meal. A qualitative and quantitative assessment of the gastric content in the antrum was performed by a blinded sonographer. The antrum was considered either as empty, or containing clear or thick fluid, or solids. Total gastric volume was predicted based on a cross-sectional area of the antrum. A p-value less than 0.05 was considered statistically significant. Results: For each type of gastric content, the sonographic characteristics of the antrum and its content were described and illustrated. Sonographic qualitative assessment allowed to distinguish between an empty stomach and one with different kinds of meal. The predicted gastric volume was significantly larger after the consumption of any food source compared to fasting. Conclusion: Bedside sonography can determine the nature of gastric content. It is also possible to estimate the difference between an empty gastric antrum and one that has some food in it. Such information may be useful to estimate the risk of aspiration, particularly in situations when prandial status is unknown or uncertain.

Resumo Objetivo: A aspiração pulmonar do conteúdo gástrico é uma das complicações mais temidas em anestesia. A sua prevenção depende do jejum pré-operatório e da identificação dos pacientes de risco. Não há um método diagnóstico que possa acessar o conteúdo gástrico a qualquer momento. O objetivo deste estudo realizado em voluntários foi fazer uma avaliação qualitativa e quantitativa do conteúdo gástrico utilizando a ultrassonografia. Método: O estudo foi realizado em 67 voluntários utilizando uma técnica já descrita de avaliação do antro gástrico, em quatro diferentes situações: jejum, após a ingestão de líquido claro, leite ou refeição sólida. Foi feita uma avaliação qualitativa e quantitativa do conteúdo gástrico por um radiologista que desconhecia o estado gástrico do voluntário. O antro foi considerado vazio, contendo líquido claro ou espesso, ou sólido. O volume total do estômago foi calculado com base na área seccional do antro. Um valor de p<0,05 foi considerado estatisticamente significativo. Resultados: Para cada tipo de conteúdo gástrico, as características ultrassonográficas do antro e de seu conteúdo foram descritas e ilustradas. A avaliação qualitativa pode distinguir um estômago vazio de outros com diferentes conteúdos. O volume gástrico calculado foi significativamente maior após a ingestão de qualquer alimento em comparação com o jejum. Conclusão: A ultrassonografia à beira do leito pode determinar a natureza do conteúdo gástrico. Também foi possível diferenciar um antro vazio daquele com algum volume. Essas informações podem ser úteis na determinação do risco de aspiração gástrica, principalmente se a condição gástrica é desconhecida ou incerta.

Pseudotumor of the Omentum Associated with Migration of the Ingested Crab-Leg

Foreign body ingestion is not uncommon in clinical practice, and it may occasionally lead to penetration injuries. Emergency physicians and radiologists sometimes fail to obtain complete histories including ingestion and may overlook the possibility of foreign body-induced complications. Herein, we report a case of stomach antrum perforation due to foreign body migration. We were unaware of the patient's history of eating the Korean delicacy "Kanjang-gaejang," which is raw crab seasoned with soy sauce. Several imaging diagnostic modalities had suggested the possibility of a malignant mass in the gastrocolic ligament area. During the operation, a crab leg was discovered as the cause of an intra-abdominal abscess. The patient underwent an antrectomy, a vagotomay, and a transverse colon wedge resection. We present this unusual case of a pseudotumorous lesion caused by ingestion of Kanjang-gaejang.

Pyloric and antral webs in infants and children: underestimated entity?

The true incidence of pyloric and antral webs in infancy and childhood is debatable. Some authors claim to be rare, others present it as a condition occurring in epidemic form. Form 1992 through 1994, 10 patients with pyloric and antral webs were managed at Ain Shams University Hospitals. There were 5 girls and 5 boys with ages ranging firm 5 days to 5 years. The main presenting symptom was repeated non-bilious vomiting, Upper gastrointestinal barium study confirmed the presence of gastric outlet obstruction in all cases but typical signs of pyloric and antral webs were identified in only 6 patients. All patients underwent incision of the web and pyloroplasty with eventual recovery postoperatively. The finding of these 10 patients within this period suggests that the condition is not as rare as previously thought. Though some authors believe the value of conservative management on the assumption that the condition is self limiting, in all our patients treatment was basically surgical due to severity and persistence of symptoms that failed to respond to conservative management