Peripheral venous (PV) catheters are often used for serial blood sampling, but studies suggest that PV catheters increase markers of coagulation activation and inflammation. Whether the increase is caused by irritation of the vessel wall or diurnal variation is unknown. We therefore compared the effects of a PV catheter and repeated venepunctures on markers of coagulation, inflammation, and endothelial function.

A PV catheter was inserted at 07:45 in a hand vein in 10 healthy subjects, and blood samples were collected at 8:00, 10:00, 12:00, and 14:00. In the contralateral arm, blood was simultaneously obtained by venepunctures. Measures of coagulation, i.e., activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen, prothrombin fragment 1 + 2 (F1 + 2) and thrombin-antithrombin (TAT), inflammation, i.e., interleukin 6 (IL-6) and C-reactive protein (CRP), and endothelial function, i.e., plasminogen activator inhibitor 1 (PAI-1), tissue plasminogen activator (tPA), von Willebrand factor (vWF), and tissue factor (TF) were measured in plasma.

The concentrations of TAT and F1 + 2 were significantly increased (10:00; p < .01, 12:00; p < .05, and 14:00; p < .01) in PV catheter samples compared with venepuncture samples. There was a minor increase in PT and INR and no increase in APTT, fibrinogen, CRP, PAI-1, tPA, vWF, and TF, with no differences between sampling methods. IL-6 concentrations increased in many PV catheter samples and venepuncture samples, but the response varied between the subjects.

Blood collection through a PV catheter induces coagulation activation, whereas endothelial function is not affected. More studies are needed to disclose the effect of blood sampling on IL-6.

外周静脉（PV）导管经常用于连续血液采样，但是研究表明PV导管会增加凝血激活和炎症的标志物。这种增加是由血管壁刺激引起的还是昼夜变化尚不清楚。因此，我们比较了PV导管和反复静脉穿刺对凝血，炎症和内皮功能标记物的影响。

在10例健康受试者的手静脉中于07:45插入PV导管，并在8：00、10：00、12：00和14:00采集血液样本。在对侧手臂中，通过静脉穿刺同时获得血液。凝血措施，即活化的部分凝血活酶时间（APTT），凝血酶原时间（PT），纤维蛋白原，凝血酶原片段1 + 2（F1 + 2）和凝血酶-抗凝血酶（TAT），炎症，即白介素6（IL-6） ）和C反应蛋白（CRP）以及内皮功能，即纤溶酶原激活物抑制剂1（PAI-1），组织纤溶酶原激活物（tPA），血管性血友病因子（vWF）和组织因子（TF）的含量。

TAT和F1 + 2的浓度增加显著（10:00; p  <0.01，12：00; p  <0.05，和14:00; p  <0.01）PV导管样中静脉穿刺样品进行比较。PT和INR略有增加，而APTT，纤维蛋白原，CRP，PAI-1，tPA，vWF和TF则没有增加，两种采样方法之间没有差异。在许多PV导管样品和静脉穿刺样品中，IL-6浓度增加，但受试者之间的反应有所不同。

通过PV导管收集血液可引起凝血激活，而内皮功能不受影响。需要更多的研究来揭示血液采样对IL-6的影响。