Prince R A, Lucas D S, Fox J L
Department of Clinical Sciences and Administration, College of Pharmacy, University of Houston, Texas Medical Center, USA.
Ann Pharmacother. 1998 Sep;32(9):875-7. doi: 10.1345/aph.18042.
To determine the degree to which a dual-lumen peripheral catheter prevented precipitation of solutions known to be incompatible due to pH during simultaneous infusion in an in vitro model.
An in vitro model was devised to simulate peripheral venous blood flow from an antecubital source to systemic circulation. Ondansetron was simultaneously infused with fluorouracil, aminophylline, sodium bicarbonate, and ampicillin sodium in concentrations reflective of clinical conditions into the Twin Cath 20/22 (the dual-lumen catheter used in this experiment). Study solutions were primed with the prepared drug solution and administered for 15 minutes. Phase I used Normosol-R as the diluent to gather preliminary data; phase II used human plasma. All samples were obtained immediately before the start of the infusion and at 5, 10, and 15 minutes during the infusion, and 5 minutes after the infusion. Samples were visually inspected at each time point for precipitation and analyzed in duplicate by the appropriate stability-indicating HPLC method (except for sodium bicarbonate). Compatibility was defined as no visual evidence of precipitation and no more than 15% mean change in final versus initial concentration.
Phase I experiments showed immediate precipitation in Normosol-R within the venous flow. However, in phase II, because of the buffering capacity that plasma proteins add to plasma, no precipitation occurred. All the drug combinations used in this study have been reported to be incompatible at the concentrations tested; however, we detected no incompatibilities.
The results of this study indicate that using a dual-lumen peripheral catheter, such as the Twin Cath, may allow solutions incompatible due to pH to be administered simultaneously.
在体外模型中确定双腔外周导管在同步输注时预防因pH值导致已知不相容溶液沉淀的程度。
设计一个体外模型来模拟从肘前源到体循环的外周静脉血流。将昂丹司琼与氟尿嘧啶、氨茶碱、碳酸氢钠和氨苄西林钠以反映临床情况的浓度同时输注到Twin Cath 20/22（本实验中使用的双腔导管）中。研究溶液用制备好的药物溶液灌注并给药15分钟。第一阶段使用Normosol - R作为稀释剂收集初步数据；第二阶段使用人血浆。所有样本在输注开始前、输注期间的5、10和15分钟以及输注后5分钟立即采集。在每个时间点对样本进行目视检查以查看是否有沉淀，并通过适当的稳定性指示HPLC方法（碳酸氢钠除外）进行一式两份分析。相容性定义为无目视可见的沉淀，且最终浓度与初始浓度的平均变化不超过15%。
第一阶段实验显示在静脉血流中的Normosol - R内立即出现沉淀。然而，在第二阶段，由于血浆蛋白赋予血浆的缓冲能力，未发生沉淀。本研究中使用的所有药物组合在测试浓度下均已报道不相容；然而，我们未检测到不相容情况。
本研究结果表明，使用双腔外周导管，如Twin Cath，可能允许因pH值不相容的溶液同时给药。
