Background: With the extensive use of peripherally inserted central catheter (PICC), PICC-associated venous thrombosis (VT) has become one of the most important complications in the hospital. To reduce unnecessary color Doppler ultrasound (CDU) or imaging tests, D-dimer values are usually used to exclude VT. There is little evidence for the usefulness of the D-dimer level as an independent diagnostic marker for excluding PICC-associated VT.
Objectives: To examine the effectiveness of D-dimer concentration to be used as an independent diagnostic marker for excluding PICC-associated UEVT. Design: A retrospective case cohort study. Settings: One teaching hospital in Hunan, China. Participants: In total, 281 subjects who underwent CDU and D-dimer values after PICC placement were eligible.
Methods:The patients were categorized into the DVT unlikely group (<2 points) and the DVT likely group (≥2 points) according to their modified Wells score post PICC placement, before extubation. After the Wells score was determined, the patients underwent a D-dimer test and CDU within 7 days after D-dimer test.
Results: 281 patients were included in the final analysis. Of them, 180 patients had D-dimer value <0.5 mgL-1. There were 39 patients with upper extremity venous thrombosis identified via CDU and 78.3% with negative predictive value of D-dimer for PICC-associated VT (95% CI: 71.7–83.7%). The negative predictive value of D-dimer for SVT was 91.0% (95% CI: 85.4–94.6%), which was higher than that for DVT (84.9%, 95% CI: 78.7–89.6%) and for VT in the cancer population (80.0%, 95% CI: 73.2–85.4%) and the non-cancer population (60.0%, 95% CI: 35.7–80.2%).
Conclusion: the D-dimer concentration should not be used as a diagnostic index to rule out PICC-associated VT to avoid missed diagnosis of PICC-related venous thrombosis, which may cause adverse consequences or may even be life-threatening.