Fagerman K E, Paauw J D, McCamish M A, Dean R E
Am J Hosp Pharm. 1984 Jun;41(6):1122-6.
Bacterial contamination and the effects of time, temperature, and preservative on bacterial growth in enteral nutrient solutions were studied. Bacteria were counted after 24-hour incubation of five samples of frozen Travasorb STD (Travenol Laboratories) from the pharmacy and five samples freshly reconstituted in the dietary department. Growth in samples of Travasorb STD prepared in the pharmacy was studied after (1) fresh mixing, 24-hour refrigeration, and 12 hours at room temperature, (2) freezing, thawing, and 12 hours at room temperature, and (3) freezing, thawing, 24-hour refrigeration, and 12 hours at room temperature. Duplicate samples of five products [Ensure (Ross Laboratories), Precision LR (Doyle Pharmaceuticals), Travasorb STD, Vital (Ross Laboratories), and Vivonex STD ( Norwich -Eaton)] were inoculated with Enterobacter cloacae, and growth curves for 24 hours were plotted. This challenge study was repeated using Travasorb STD as a control and Travasorb STD with potassium sorbate added. Bacterial contamination following reconstitution was not significantly different between pharmacy and dietary department samples. Growth after 12 hours at room temperature was not significantly different for the three sets of storage conditions. Logarithmic growth occurred only at room temperature. All products supported growth of E. cloacae, but growth was significantly lower in Vivonex STD (which contains potassium sorbate) and Precision LR. Growth was reduced by 70% versus control at 12 hours in Travasorb STD containing 0.036% potassium sorbate and by 90% with 0.2% potassium sorbate. Microbial growth in enteral nutrient solutions was dependent on the initial inoculum and the storage time at room temperature. Addition of potassium sorbate to these solutions may greatly reduce bacterial growth.
研究了细菌污染以及时间、温度和防腐剂对肠内营养液中细菌生长的影响。对药房提供的五份冷冻的特拉伐索标准型（Travenol Laboratories公司生产）样本和膳食科新配制的五份样本进行24小时培养后对细菌进行计数。对药房配制的特拉伐索标准型样本在以下情况下进行了生长研究：（1）新鲜混合、24小时冷藏以及室温下放置12小时；（2）冷冻、解冻以及室温下放置12小时；（3）冷冻、解冻、24小时冷藏以及室温下放置12小时。将五种产品[安素（Ross Laboratories公司）、精准LR（Doyle Pharmaceuticals公司）、特拉伐索标准型、活力（Ross Laboratories公司）和维沃力标准型（Norwich - Eaton公司）]的重复样本接种阴沟肠杆菌，并绘制24小时的生长曲线。以特拉伐索标准型作为对照以及添加山梨酸钾的特拉伐索标准型再次进行了这项挑战性研究。药房样本和膳食科样本复溶后的细菌污染情况没有显著差异。三种储存条件下室温放置12小时后的生长情况没有显著差异。对数生长仅发生在室温下。所有产品都支持阴沟肠杆菌的生长，但维沃力标准型（含有山梨酸钾）和精准LR中的生长明显较低。在含有0.036%山梨酸钾的特拉伐索标准型中，12小时时生长相对于对照降低了70%，在含有0.2%山梨酸钾时降低了90%。肠内营养液中的微生物生长取决于初始接种量和室温下的储存时间。向这些溶液中添加山梨酸钾可能会大大减少细菌生长。
