Positional effects on femoral vein cross-sectional area: a prospective ultrasonographic study

Abstract

Aims: The study aimed to assess the variation in femoral vein diameter and cross-sectional area (CSA) across different body positions in a cohort of healthy Turkish adults and to explore the associations between venous measurements and demographic variables, including age, sex, and body-mass index (BMI). Methods: Ultrasonographic measurements of the right and left femoral vein diameters and CSA were obtained in five distinct body positions from 278 healthy adults, encompassing a total of 556 lower limbs. Demographic parameters, including age, sex, and BMI, were systematically documented for each participant. Results: A total of 278 participants (556 limbs) were analysed. Males exhibited significantly higher femoral vein CSA than females across all positions (p<0.001). The lowest mean CSA was in the Trendelenburg position (0.87±0.08 cm²), and the highest in the reverse Trendelenburg+frog-leg position (1.51±0.11 cm²) (p<0.001). CSA positively correlated with age in all positions except Trendelenburg (r=0.400–0.479, p<0.001). Overweight and obese (class I) individuals showed significantly higher CSA values than normal or underweight participants (p<0.001). Conclusion: This study demonstrates that body positioning significantly affects the CSA of the femoral vein. Additionally, factors such as age, sex, and BMI were found to significantly influence femoral vein calibre.

Keywords

• Femoral vein
• cross-sectional area
• ultrasonography

References

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