Palpation versus Ultrasound-Guided Dynamic Needle Tip Positioning Technique for Radial Artery Cannulation.

Introduction: Invasive blood pressure monitoring is the clinical reference during perioperative patient management. It is usually performed by cannulating the radial artery. Different clinical conditions make arterial cannulation difficult using the conventional palpation (CP) method. This study compares the ultrasonography (USG)-guided dynamic needle tip positioning (DNTP) technique with the CP method to assess the first-pass success rate of radial artery cannulation.

Methods: In the operation theater of a university hospital, a total of 52 adult patients requiring arterial cannulation were randomized into two equal groups. Arterial cannulation was performed using the CP method in one group and the ultrasound-guided DNTP method in the other group. The first-pass success rate was the primary objective. The 5-minute success rate, the time required for successful cannulation, the number of skin punctures, and the number of cannulae used were also compared using the Chi-square test, an independent sample t-test, and the Mann-Whitney U test.

Results: The first-pass success rate was significantly higher in the USG-guided DNTP method (88.5%) compared to the CP method (46.2%) (P 0.001). The overall 5-minute success rate was 96.2% in the USG-guided DNTP and 65.4% (P 0.005) in the CP method. The median time for successful cannulation was significantly lesser in the USG-guided DNTP group [44 s (IQR: 35-72)] compared to the CP group [134 s (IQR: 28-378)] (P 0.007). The mean number of skin punctures in the USG-guided DNTP group was 1.15 ± 0.46 and 2.04 ± 1.18 in the CP group (P 0.001).

Conclusion: USG-guided DNTP method of radial artery cannulation increased the first-pass success rate.