A study on the monitor of gastric residual volume by ultrasound and its prediction on feeding intolerance during enteral nutrition in critically ill patients in intensive care unit / 中华急诊医学杂志

ABSTRACT

Objective:To explore the feasibility of bedside ultrasound in monitoring gastric residual volume and predicting feeding intolerance during enteral nutrition in critically ill patients in intensive care unit.Methods:The data of critically ill patients admitted to emergency intensive care unit of the Second Affiliated Hospital of Zhejiang University School of Medicine from April 2018 to September 2018 were retrospectively analyzed. The following patients were finally included in this study (1) abdominal computed tomography during the stay of emergency intensive care unit was performed due to the requirement of disease evaluation and management; (2) bedside ultrasound was performed to measure the gastric antrum cross-sectional area at 30 min prior to or after abdominal computed tomography. The outline of stomach wall in the imaging of abdominal computed tomography was traced with the help of VOLUME-Work Flow medical imaging software to calculate the value of gastric residual volume. The relationship between gastric antrum cross-sectional area under semi-sitting, horizontal and right-lateral positions and gastric residual volume was evaluated by Pearson correlation analysis. The difference of gastric antrum cross-sectional area between those critically ill patients with or without feeding intolerance was compared by independent-sample t test. The predictive value of gastric antrum cross-sectional area under different body positions on feeding intolerance during enteral nutrition was analyzed by ROC curve. Results:Totally, forty-two patients were enrolled and analyzed in this study, in which the mean age was (53±13) y, mean body mass index was (21.5±2.8) kg/m 2 and mean acute physiology and chronic health evaluation was 17.0±6.9. The value of gastric residual volume was (314.5±126.6) mL, and the values of gastric antrum cross-sectional area under semi-sitting, horizontal and right-lateral positions were (7.11±4.13) cm 2, (4.22±2.66) cm 2, (8.36±4.58) cm 2, respectively. The correlation analysis indicated that gastric residual volume was positively associated with gastric antrum cross-sectional area under semi-sitting, horizontal and right-lateral positions ( r=0.543, 0.604 and 0.618, respectively; all P<0.001). During enteral nutrition, 15 patients experienced feeding intolerance while 27 patients hadn’t feeding intolerance, in which the gastric antrum cross-sectional areas under semi-sitting, horizontal and right-lateral positions were significantly increased in those patients with feeding intolerance than those patients without feeding intolerance [semi-sitting (8.53±4.07) cm 2vs (4.60±2.76) cm 2; horizontal position (5.15±2.75) cm 2vs (2.61±1.32) cm 2; right-lateral position (10.32±4.06) cm 2vs (4.95±3.20) cm 2, all P<0.005] . ROC curve analysis showed that the area under ROC curves of gastric antrum cross-sectional area under semi-sitting, horizontal and right-lateral positions for predicting feeding intolerance during enteral nutrition were 0.815, 0.833 and 0.849, respectively; when its values≥3.917 cm 2, 3.395 cm 2 and 4.402 cm 2 were used as the cut-off points, the sensitivities were 92.0%, 69.6% and 92.3%, and the corresponding specificities were 69.2%, 92.3% and 71.4%, respectively. Conclusions:Bedside gastric ultrasound could accurately evaluate the status of gastric residual volume in critically ill patients, and effectively predict their occurrence of feeding intolerance during enteral nutrition.