腸內營養評估

　　 當前，重癥病人營養支持治療相關指南及共識推薦危重癥患者入住ICU24h-48h內盡早啟動腸內營養。腸內營養有助于營養胃腸黏膜，增強神經內分泌功能，有益于保留腸道黏膜屏障功能和免疫功能。早期腸內營養與降低感染率，加速傷口愈合，縮短機械通氣時間、ICU住院時間和總體住院時間，以及降低病死率有關。在臨床實踐中，由于ICU病人的個體差異性較大，不同病種或病程病人胃腸功能受損程度不同、對腸內營養的耐受性差異很大，胃腸功能障礙重癥病人開展腸內營養支持治療仍充滿挑戰。本期，對于胃腸耐受性和胃殘余量的評估進行介紹。 　　

1.Gastric emptying and gastric retention monitoring【胃排空與胃潴留監測】

Gastric residual measurement is the most common method for evaluating gastric retention, including classical measurement, modified measurement and ultrasound assessment. Gastric residual volume≥250 mL indicates feeding intolerance, and intervention therapy should be started as soon as possible.

胃殘余量測量是評估胃潴留最常見的方法，包括經典測量法、改良測量法和超聲檢查評估法。胃殘余量≥250 mL提示喂養不耐受，需盡早啟動干預治療。

胃殘余量的測量方法

Classical measurement: After stopping nasogastric feeding, the nutrition pump tube was removed, and the nasogastric tube was connected with a 50 mL or 60 mL syringe. The total amount of stomach contents extracted from multiple syringes was the gastric residual amount.

經典測量：停止鼻飼后，脫開營養泵管，使用50 mL或60 mL規格注射器連接鼻胃管后回抽，多個注射器回抽得的胃內容物總量即為胃殘余量。

FIGURE1-1 Gastric fluid is aspirated to determine gastric residual volume

（抽吸胃液確定胃殘余量）

Ultrasound measurement: Bedside ultrasound evaluation of gastric residual volume in healthy or critically ill patients has a good linear relationship with its stomach contents. Measurements of the cross-sectional area (CSA) of the gastric antrum by ultrasound are performed as follows: The patient is supine, the head of the bed is raised 30°(if the vertebra or pelvis is fractured, the overall slope of the bed is raised 30°), and the convex array ultrasound probe is placed in the superior abdominal area of the patient. The probe is parallel to the longitudinal axis of the body, and the indicator point is pointed at the patient's head side. The probe is scanned from left to right, and the fundus of the stomach, the body of the stomach and the section of the pylorus can be observed in turn, and the sagittal cross-section image of the pylorus can be obtained. Anterior and posterior diameter (Dap) and cephalic and tail diameter (Dcc) were measured according to the formula: usCSA (cm2) = (Dap×Dcc×π) /4, stomach volume (mL) =27.0+14.6×CSA -- 1.28×age. Results of a systematic review showed that gastric volume >1.5 mL/kg indicated a high risk of aspiration.

超聲檢查測量：床旁超聲檢查評估胃殘余量在健康人或重癥病人的測量結果與其胃內容物量有良好的線性關系。通過超聲檢查測量胃竇橫截面積 （cross-sectional area，CSA） 評估胃殘余量的具體操作如下：病人仰臥位，床頭抬高30°（若椎體或骨盆骨折，則床整體斜坡抬高30°），將凸陣超聲探頭放置在病人腹上區，探頭與身體縱軸平行，指示點指向病人頭側，探頭自左向右滑動掃描，依次可觀察胃底、胃體及幽門切面，獲取幽門部矢狀位橫截面圖像，測量前后徑（Dap）及頭尾徑（Dcc），根據公式：usCSA（cm2）=（Dap×Dcc×π）/4，胃容量（mL）=27.0+14.6×CSA?1.28×年齡。一項系統性回顧分析結果顯示：若測得胃內容量>1.5 mL/kg，提示高誤吸風險。

FIGURE 1-2 The gastric contents were quantitatively determined by ultrasound

（經超聲胃內容物定量測定）

2.Evaluation of tolerance to enteral feeding【腸內喂養耐受性評估】

Feeding intolerance refers to the reduction of enteral nutrient infusion during feeding due to various reasons. Assessment of feeding intolerance is usually based on gastrointestinal symptoms such as high residual stomach volume, vomiting, bloating, diarrhea, etc.

喂養不耐受指喂養過程中由于各種原因導致的腸內營養輸注量減少。評估喂養不耐受通常基于胃腸道癥狀，如高胃殘余量、嘔吐、腹脹、腹瀉等。

TABLE 2-1 Score sheet of tolerance for enteral nutrition

（腸內營養耐受性評分表）

參考文獻

　　[1]亞洲急危重癥協會中國腹腔重癥協作組.重癥病人胃腸功能障礙腸內營養專家共識（2021版）[J].中華消化外科雜志, 2021,20(11):1123-1136. DOI:10.3760/cma.j.cn115610-20211012-00497.