BackgroundThe purpose of the study was to assess blood flow in the upper limb arteries after prolonged catheterization with long radial artery catheters (LRC) which reach the subclavian artery compared to catheterization with standard short radial artery catheters (SRC) and a group of upper limb flow without any catheter placement (NOCATH), with both SRC and NOCATH as control groups.MethodsProspective observational study with 20 patients admitted to ICU (40 upper limbs) with LRC and/or SRC inserted >48 h for hemodynamic monitoring. More than 45 days after catheter withdrawal, patients underwent a Doppler ultrasound study of both upper limbs. Arterial flows of arms with LRC (FlowLRC) were compared with arterial flows of arms with SRC (FlowSRC) and those without any catheter (FlowNOCATH).ResultsFlow in the ulnar, brachial, and subclavian arteries did not show any significant difference between the two types of catheters. The only significant difference was in the radial arteries, showing a lower mean flow in the arms with LRC than in the arms with SRC (2.2 vs. 8.5 cc/min; p = 0.041). Flow reduction in the radial artery (74%) in the arms with LRC compared to the SRC arms showed a tendency to increase ulnar flow as a compensatory mechanism. None of the patients with LRC included in our study had any ischemic events, in spite of observing complete flow occlusion in three radial arteries (18%) from the Doppler study.ConclusionsIn this sample, the use of PiCCO long radial catheters reaching the subclavian artery did not produce chronic significant changes in brachial or subclavian flows. However, LRC produces a significant reduction in radial flow and a tendency to increase ulnar flow. When comparing these blood flow changes with those produced by SRC use, only the radial flow reduction was significantly lower, whereas the other arterial flow changes did not significantly differ.