Impact of sex, age and BMI on depth and diameter of the infraclavicular axillary vein when measured by ultrasonography

Abstract

The axillary vein is another option for central venous catheterisation, with less chance of accidental arterial puncture as there is a greater distance between artery and vein, and from vein to rib cage, compared with other sites. Better success, lower complication rates and faster access can be achieved with ultrasound guidance which is becoming the established technique for central venous catheterisation. We measured two key factors for successful infraclavicular axillary venous catheterisation: depth and diameter of the infraclavicular axillary vein in its medial part using ultrasound. We recruited 98 patients, classified according to sex, age and BMI. Groups were divided according to BMI as follows: group 1 (≤20 kg m⁻²), group 2 (20.01-25.00 kg m⁻²) and group 3 (>25 kg m⁻²); and these were further subdivided according to age: 20-39 years, 40-59 years and 60-80 years. The depth and diameter of the infraclavicular axillary vein was measured at a point between the medial third and midpoint of the clavicle. Vein diameter was significantly different between men and women (P = 0.005), whereas depth showed no significant difference. In the BMI subgroups, there was a significant difference in depth (P < 0.001), and a trend to significant difference in diameter (P = 0.056). However, age-specific differences in depth and diameter were not observed. During catheterisation of infraclavicular axillary vein, real-time visualisation of the needle tip when using ultrasound to gauge vein depth and diameter may diminish major complications such as pneumothorax and artery puncture.