Impact of edema severity on basilic and superficial femoral vein diameters: Implications for peripherally inserted central catheter placement in critically ill patients.

Background: Edema in critically ill patients poses challenges for vascular access, particularly during peripherally inserted central catheter (PICC) placement. The cross-sectional area of veins significantly influences catheterization success and complication rates.

Objective: This study investigates the relationship between edema severity and the diameters of the basilic vein and superficial femoral vein (mid-thigh level) to optimize vascular access strategies.

Material and methods: A retrospective analysis of 11 intensive care unit (ICU) patients from a tertiary medical center in Taiwan was conducted, using medical records collected between August 2023 and May 2024. The study examined the association between ultrasound-graded edema severity and venous diameters. A random-effects linear panel data regression model was applied to assess the relationship, with statistical significance defined as p < .05.

Results: Increasing edema severity was significantly associated with a reduction in basilic vein diameter (p < .001), while no significant changes were observed in the superficial femoral vein (p = .44). Adjustments for confounders did not alter these findings. The basilic vein exhibited a linear trend decrease of -0.7 mm per edema grade, while the femoral vein remained relatively unaffected.

Conclusion: Edema significantly narrows the basilic vein but spares the superficial femoral vein; if further swelling is anticipated, avoid basilic PICC placement and instead use the superficial femoral vein, of which the diameter remains comparatively stable.