Ultrasound-guided dynamic needle tip positioning technique for radial artery cannulation in elderly patients: A prospective randomized controlled study

Abstract

Background: Radial artery cannulation, which is a useful procedure for anesthetic management, is often challenging in elderly patients. Recently, the dynamic needle tip positioning (DNTP) technique was introduced to facilitate ultrasound-guided vascular catheterization. Therefore, we performed this prospective, parallel group, randomized, controlled trial to compare the ultrasound-guided DNTP technique with the palpation method in elderly patients.

Methods: For this study, 256 patients aged 65 years or older were randomly allocated to the ultrasound-guided DNTP technique group (DNTP group) or the palpation method group (palpation group). The primary outcome was first-attempt success rate. The secondary outcomes were overall success rate, numbers of attempts and redirections, cannulation time, and incidence of complications.

Results: The first-attempt success rate (85.9% vs. 72.3%; relative risk [RR], 1.47; 95% CI 1.25-1.72; P<0.001) and the overall success rate (99.2% vs. 93.0%; RR, 1.07; 95% CI 1.02-1.12; P = 0.01) were significantly higher in the DNTP group compared to the palpation group. The numbers of attempts [1 (1,1) vs. 1 (1,3), P<0.001] and redirections [0 (0,1) vs. 2 (0,4), P<0.001] were significantly lower in the DNTP group. The cannulation time for successful attempts was 42 (32,55) seconds in the DNTP group and 53 (36,78) seconds in the palpation group (P<0.001). The incidence of hematoma was significantly lower in the DNTP group (7% vs. 24.2%; RR, 0.29; 95% CI, 0.14-0.59; P<0.001).

Conclusions: Ultrasound-guided radial artery cannulation with the DNTP technique improved the efficiency of radial artery cannulation in elderly patients by increasing the success rate while minimizing complications.

Fig 1. Flow diagram of patient recruitment and exclusion criteria for the study.

DNTP, dynamic needle tip positioning technique.

Fig 2. Ultrasound-guided DNTP technique.

The radial artery (RA) was identified in an out-of-plane approach with an ultrasound probe. (A) The needle was inserted through the skin, and the needle tip (arrowhead) appeared as a hyperechoic dot on the display. (B) The probe was moved slightly further without moving the needle, and the hyperechoic dot disappeared as the needle tip exited the ultrasound plane. (C) The needle was advanced toward the radial artery with the probe held in place, and the needle punctured the radial artery. (D) The probe was moved proximally again, and the needle tip disappeared from the display. (E) The needle was advanced, and it was confirmed that the needle tip remained in the radial artery. Arrowheads on the ultrasound images indicate the needle tip of the angiocatheter. DNTP, dynamic needle tip positioning.