Comparison of ultrasound-guided dynamic needle tip positioning and acoustic shadowing technique with palpation technique for radial arterial cannulation by experienced clinicians: A randomized controlled trial.

Background: Radial artery cannulation is usually done for monitoring invasive blood pressure during intraoperative period. The dynamic needle tip positioning approach allows continuous visualization of the needle tip during ultrasound-guided cannulation. The acoustic shadowing technique, using two lines on the ultrasound probe, might be used to facilitate radial artery puncture. We aimed to compare these two ultrasound-guided techniques of radial artery cannulation with the traditional palpation method in adult patients.

Methods: In this trial, 180 adult patients requiring arterial cannulation were randomized into three groups (Traditional palpation (TP), Dynamic needle tip positioning (DNTP), and acoustic shadow technique (AST)). All cannulations were carried out by experienced anesthetists. Data was analyzed for the success rate of arterial cannulation in the first attempt, total number of attempts in 5 min, time taken to cannulate, number of cannulas used, and complications related to the procedure.

Results: The first attempt success rates among TP, DNTP, and AST were 66.7%, 66.7%, and 71.7%, respectively ( = 0.794). The median time taken for cannulation was 60.5 (37.0, 129.5) s, 71.0 (50.0, 170.0) s, and 108.0 (58.0, 181.0) s, respectively ( = 0.066) and the median number of cannulation attempts was 1, in all the three groups ( = 0.684). There was also no difference in the total number of cannulas used, the overall success rate of cannulation, and complications related to the procedure in the three groups.

Conclusion: The TP, DNTP, and AST technique for radial artery cannulation had comparable first attempt success rate, the time taken for cannulation, the number of cannulas used, and overall complications. We conclude that radial arterial cannulation by palpation, as well as ultrasound-guided DNTP and AST techniques performed by experienced clinicians in hemodynamically stable adult patients are equally advantageous.