Evaluation of gastric emptying after drinking carbohydrates before cesarean section by gastric ultrasonography / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effect of gastric antrum ultrasonography in evaluating gastric emptying after oral administration of 300 mL carbohydrates two hours before cesarean section, and to analyze the risk factors of gastric emptying in pregnant women.@*METHODS@#From August 2020 to February 2021, a total of 80 patients, aged 22-43 years, body mass index (BMI) < 35 kg/m2, gestational age≥36 weeks, falling into American Society of Anesthesiologists (ASA) physical status Ⅰ or Ⅱ, scheduled for cesarean sections in Peking University International Hospital were recruited and divided into two groups: the intervention group (n=40)and the control group (n=40). In the intervention group, solid food was restricted after 22:00, the patients were required to take 300 mL carbohydrates two hours before cesarean section. In the control group, solid food and liquid intake were restricted after 22:00 the night before surgery. All the patients received assessment of preoperative feeling of thirst and starvation with visual analogue scale (VAS). The cross-sectional area (CSA)of gastric antrum was measured in supine position and right supine position before anesthesia, the gastric volume (GV)and the gastric volume/weight(GV/W)of the two groups was further calculated. Perlas A semi-quantitative grading assessments were performed in each patient. The blood pressure and heart rate were recorded at admission(T0), 5 minutes after anesthesia (T1), immediately after fetal delivery (T2) and at the end of the surgery (T3). The occurrence of nausea and vomiting during the operation and 24 hours after the operation were recorded.@*RESULTS@#One case in each group was excluded because the antrum was not clearly identified during the ultrasound assessments. In the semi-sitting position, the CSA was (5.07±1.73) cm2 in the intervention group vs. (5.24±1.96) cm2 in the control group, respectively; in the right lateral decubitus position, CSA was (7.32±2.17) cm2 in the intervention group vs. (7.25±2.24) cm2 in the control group, GV was (91.74±32.34) mL vs. (90.07±31.68) mL, GV/W was (1.27±0.40) mL/kg vs. (1.22±0.41) mL/kg, respectively; all the above showed no significant difference between the two groups (P > 0.05). Perlas A semi-quantitative grading showed 0 in 20 patients (51.3%), 1 in 16 (41%), 2 in 3 (7.7%)in the intervention group and 0 in 22 (56.4%), 1 in 15 (38.5%), 2 in 2 (5.1%)in the control group, the proportion of Perlas A semi-quantitative grading showed no significant difference between the two groups (P > 0.05). For the patients with Perlas A semi-quantitative grade 2 (3 cases in the intervention group and 2 cases in the control group), metoclopramide 0.2 mg/kg was intravenously injected before anesthesia. No aspiration case was observed in this study. The intervention group was endured less thirst and hunger (P < 0.05). There was no significant difference in blood pressure and heart rate between the two groups at each time point (P > 0.05). There was no significant difference in the incidence of intraoperative hypotension between the two groups (P > 0.05). There was no significant difference in the incidence of nausea intraoperatively and postoperatively between the two groups (P > 0.05).@*CONCLUSION@#Ultrasonography of gastric antrum can provide objective basis for evaluating gastric emptying of pregnant women perioperatively. 300 mL carbohydrates intake two hours before surgery, which does not increase GV and the risk of reflux aspiration, and is helpful in minimizing disturbance to the patient's physiological status, therefore leading to better clinical outcome.

Effect of preoperative carbohydrates intake on the gastric volume and the risk of reflux aspiration in patients positioning in trendelenburg undergoing gynecological laparoscopic procedures / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effect of 300 mL carbohydrates intake two hours before sur-gery on the gastric volume (GV) in patients positioning in trendelenburg undergoing gynecological laparoscopic procedures by using gastric antrum sonography, and further assess the risk of reflux aspiration.@*METHODS@#From June 2020 to February 2021, a total of 80 patients, aged 18-65 years, body mass index (BMI) 18-35 kg/m2, falling into American Society of Anesthesiologists (ASA) physical status Ⅰ or Ⅱ, scheduled for gynecological laparoscopic procedures positioning in trendelenburg were recruited and divided into two groups: the observation group (n =40) and the control group (n=40). In the observation group, solid food was restricted after 24:00, the patients were required to take 300 mL carbohydrates two hours before surgery. In the control group, solid food and liquid intake were restricted after 24:00 the night before surgery. The cross-sectional area (CSA) of gastric antrum was measured in supine position and right lateral decubitus position before anesthesia. Primary outcome was gastric volume (GV) in each group. Secondary outcome included Perlas A semi-quantitative grading and gastric volume/weight (GV/W). All the patients received assessment of preoperative feeling of thirsty and hunger with visual analogue scale (VAS).@*RESULTS@#Complete data were available in eighty patients. GV was (58.8±23.6) mL in the intervention group vs. (56.3±22.1) mL in the control group, GV/W was (0.97±0.39) mL/kg vs. (0.95±0.35) mL/kg, respectively; all the above showed no significant difference between the two groups (P > 0.05). Perlas A semi-quantitative grading showed 0 in 24 patients (60%), 1 in 15 patients (37.5%), 2 in 1 patient (2.5%) in the intervention group and 0 in 25 (62.5%), 1 in 13 (32.5%), 2 in 2 (5%) in the control group, the proportion of Perlas A semi-quantitative grading showed no significant difference between the two groups (P > 0.05). A total of 3 patients (1 in the intervention group and 2 in the control group) with Perlas A semi-quantitative grading 2 were treated with special intervention, no aspiration case was observed in this study. The observation group endured less thirst and hunger (P＜0.05).@*CONCLUSION@#Three hundred mL carbohydrates intake two hours before surgery along with ultrasound guided gastric content monitoring does not increase gastric volume and the risk of reflux aspiration in patients positioning in trendelenburg undergoing gynecological laparoscopic surgery, and is helpful in minimizing disturbance to the patient's physiological needs, therefore leading to better clinical outcome.

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.