AJG：胃管给予要素饮食可有效降低误吸

长期卧床需要行经皮内镜下胃造瘘术，通过胃管给予营养支持的患者，出现食物误吸入气管出现吸入性肺炎的几率很高，并且并发吸入性肺炎的患者预后差、死亡率高。日本驹根市昭和阿齐兹·伊南总医院消化病科的Akira Horiuchi等人，在临床实践中发现给予要素饮食可有效降低吸入性肺炎的发生率，所以针对这一问题进行了随机对照性的研究，发现给予要素饮食，较标准流质饮食而言，胃排空的速度增加，发生误吸的几率减少，由此得出结论，建议对于长期卧床需要经皮内镜下胃造瘘术胃管给予营养的患者，特别是出现过吸入性肺炎的患者，推荐给予要素性饮食。这一结果发表在2013年3月的The American journal of gastroenterology上。

因临床实践表明给予长期卧床、行经皮内镜下胃造瘘术的患者要素性饮食，可明显减少吸入性肺炎的发生。我们对比了卧床患者行经皮内镜下胃造瘘术经胃管给予要素性流质及标准流质的效果、发生吸入性肺炎的风险以及胃排空的情况。

作者的实验方案涉及两方面内容：研究1：持续卧床的患者经同样的方式给予要素性饮食以及标准流质。在住院期间详细记录患者大便次数、经气管吸入食物的次数以及出现吸入性肺炎的情况。研究2：对所有卧床行经皮内镜下胃造瘘术的患者给予随机、交叉的要素饮食及标准流质饮食，并且食物中含有¹³C乙酸盐作为示踪物。发生吸入性肺炎的患者¹³C呼气阳性。同时采用¹³C呼气试验检测其胃排空情况。研究1结果：试验共涉及了127名患者，60名给予要素饮食，67名给予标准流质饮食。要素饮食组出现经气管吸入食物的比例为0%，而这一比例在标准流质饮食组中为11.9%（8人），两组比较差异具有统计学意义（P=0.0057）。吸入性肺炎同样未在要素饮食组出现，而标准流质饮食组中有5人出现吸入性肺炎（7.5%），差异同样具有统计学意义（P=0.031）。（需要治疗的人数为14人，95%可信区间为7-85）。研究2结果:实验涉及了19名患者。要素饮食可以显著减少胃排空（排泄）10%，30%，50%所需时间(P<0.001)，与标准流质饮食组比较剂量相关的曲线下面积（百分比）明显增加(P<0.05)。

经过实验发现在长期卧床、行经皮内镜下胃造瘘术的患者中，与给予标准流质饮食比较，给予要素性饮食能够明显加快胃的排空，并减少误吸的出现。对于长期卧床需要经皮内镜下胃造瘘术胃管给予营养的患者，特别是出现过吸入性肺炎的患者，推荐给予要素性饮食。要素饮食的优点还需要更加严格的随机-对照实验进一步证实。

Elemental diets may reduce the risk of aspiration pneumonia in bedridden gastrostomy-fed patients.
OBJECTIVES
Our clinical experience suggested that elemental diets were associated with a reduction in aspiration pneumonia among bedridden patients with percutaneous endoscopic gastrostomy (PEG). We compared the effects of elemental and standard liquid diets on the risk of clinical aspiration pneumonia and gastric emptying in bedridden patients receiving PEG feedings.
METHODS
Study 1: consecutive bedridden PEG patients received elemental diets or standard liquid diets in the same fashion. The frequency of defecation, diet aspirated from the trachea, and aspiration pneumonia during hospitalization were prospectively recorded. Study 2: a randomized, crossover trial using elemental or standard liquid diets containing (13)C sodium acetate as a tracer given to bedridden PEG patients who had experienced aspiration pneumonia. (13)C breath tests were performed to estimate gastric emptying.
RESULTS
Study 1: 127 patients were enrolled, 60 with elemental and 67 with standard liquid diets. The diet was aspirated from the trachea in none (0%) with the elemental diet vs. 8 (11.9%) with standard liquid diets (P=0.0057); aspiration pneumonia developed none with the elemental diet vs. 5 (7.5%) with standard liquid diets (P=0.031) (number needed to treat 14, 95% confidence interval 7-85). Study 2: 19 patients were enrolled. The elemental diet was associated with a significant increase in the 10, 30 or 50% emptying (excretion) time (P<0.001) and increased the area under the curve (% dose/h) compared with the standard liquid diet (P<0.05).
CONCLUSIONS
Elemental diets were associated with more rapid gastric empting and fewer episodes of aspiration than standard liquid diets in bedridden PEG patients. They may be preferred for bedridden PEG patients especially who have experienced aspiration pneumonia. Properly performed randomized-controlled trials are needed to prove this potential benefit.