Background: Antegrade cannulation of peripheral veins is the usual practice. Blood stasis between a catheter and the wall of the vein or at its tip in addition to catheter-induced phlebitis may initiate a thrombosis. The use of retrograde ventriculojugular shunts against the direction of the blood flow with resultant decrease in the incidence of venous thrombosis encouraged us to compare retrograde versus conventional antegrade peripheral venous cannulation.
Methods: Monocentric, nonblinded, prospective observational cohort of 40 intensive care unit patients receiving 2 peripheral venous catheters in upper limbs, 1 inserted in the direction of blood flow (antegrade cannula) and the other inserted in an opposite direction to blood flow (retrograde cannula). Daily ultrasound assessment of the angle between the catheter and the vascular wall was done to detect onset and progression of thrombus formation.
Results: The study included 40 patients, aged 46.7 ± 10.132 years. The incidence of thrombus formation was 100% in both techniques. The onset time of thrombus formation between the catheter and the wall of a vein was significantly longer with the retrograde catheters than with the antegrade catheters with median time (interquartile range [range]) 6 days (5-6.75 [4-8]) with 95% confidence interval (CI), 5.58-6.42 vs 3 days (3-4 [2-5]) with 95% CI (2.76-3.24), respectively, with a P value <.001. The time needed by the recently detected thrombus to reach the catheter tip determined by ultrasound with or without catheter failure was significantly longer in the retrograde catheters than in the antegrade catheter with median time (interquartile range [range]) 9 days (8-9 [7-10]) with 95% CI, 8.76-9.24 vs 4 days (4-5 [3-6]) with 95% CI, 3.76-4.24, respectively, with a P value <.001.
Conclusions: Retrograde cannulation did not decrease the incidence of thrombus formation, but significantly increased the onset time until thrombus formation and prolonged the time needed by the newly formed thrombus to reach the catheter tip compared with conventional antegrade cannulation.