Hydrolocation assisted subclavian venous catheterization -two case reports.

BACKGROUND: Of the three common central access sites, subclavian vein catheterization has the lowest risk of infection but the highest risk of pneumothorax. The main disadvantage of the short-axis ultrasound guided approach is difficult needle-tip visualization. We describe use of the hydrolocation technique to improve needle-tip localization. CASE: Two females, an 81-year-old and a 72-year-old, presented for coronary artery bypass grafting requiring central vein cannulation. To confirm that the needle tip was visualized and not the shaft, needle advancement was paused and 1 ml of saline injected. The appearance of a small anechoic pocket superficial to the subclavian vein helped to visualize the needle tip. Negative aspiration was then re-applied and slight advancement resulted in aspiration of blood and successful subclavian vein puncture.
CONCLUSIONS: The use of hydrolocation for subclavian vein access was easily implemented, required little modification in setup and technique, and provided improved localization of the needle tip.