Real-time ultrasound guidance facilitates transradial access: RAUST (Radial Artery access with Ultrasound Trial)

Objectives: This study sought to assess the utility of ultrasound (US) guidance for transradial arterial access.

Background: US guidance has been demonstrated to facilitate vascular access, but has not been tested in a multicenter randomized fashion for transradial cardiac catheterization.

Methods: We conducted a prospective multicenter randomized controlled trial of 698 patients undergoing transradial cardiac catheterization. Patients were randomized to needle insertion with either palpation or real-time US guidance (351 palpation, 347 US). Primary endpoints were the number of forward attempts required for access, first-pass success rate, and time to access.

Results: The number of attempts was reduced with US guidance [mean: 1.65 ± 1.2 vs. 3.05 ± 3.4, p < 0.0001; median: 1 (interquartile range [IQR]: 1 to 2) vs. 2 (1 to 3), p < 0.0001] and the first-pass success rate improved (64.8% vs. 43.9%, p < 0.0001). The time to access was reduced (88 ± 78 s vs. 108 ± 112 s, p = 0.006; median: 64 [IQR: 45 to 94] s vs. 74 [IQR: 49 to 120] s, p = 0.01). Ten patients in the control group required crossover to US guidance after 5 min of failed palpation attempts with 8 of 10 (80%) having successful sheath insertion with US. The number of difficult access procedures was decreased with US guidance (2.4% vs. 18.6% for ≥5 attempts, p < 0.001; 3.7% vs. 6.8% for ≥5min, p = 0.07). No significant differences were observed in the rate of operator-reported spasm, patient pain scores following the procedure, or bleeding complications.

Conclusions: Ultrasound guidance improves the success and efficiency of radial artery cannulation in patients presenting for transradial catheterization. (Radial Artery Access With Ultrasound Trial [RAUST]; NCT01605292).