Ultrasound Guidance and Other Determinants of Successful Peripheral Artery Catheterization in Critically Ill Children∗

Objective: Peripheral arterial catheterization is a common invasive procedure performed in critically ill children. However, the benefits of using ultrasound guidance for this procedure in critically ill children, especially when used by inexperienced trainees, are unclear. Our aims were to evaluate whether the use of ultrasound guidance for the placement of radial arterial catheters reduced time and improved success when compared with the palpation method and also to determine patient and trainee variables that influence procedure outcomes. Finally, we evaluated whether adoption of ultrasound guidance among trainees comes at the expense of learning landmark-based methods. Design: Prospective observational cohort. Setting: University affiliated PICU. Patients: A total of 208 procedures performed by 45 trainees in 192 unique patients (1 mo to 20 yr old) were observed. Intervention: Implementation of ultrasound curriculum. Measurements and Main Results: The main outcome measures were time and number of attempts required for the procedure. Compared with palpation method, ultrasound guidance was associated with reduced procedure time (8.1 ± 5.2 min compared with 16.5 ± 8.8 min; p < 0.001), reduced number of attempts (3.1 ± 2.6 attempts compared with 6.9 ± 4.2 attempts; p < 0.001), and improved first attempt success rate (28% compared with 11%; p = 0.001) even after adjusting for key confounders in multivariate random effects models. The factors most likely to interfere with peripheral arterial catheterization are patient age, patient systolic blood pressure, patient body mass index, degree of fluid overload, and trainee months in fellowship. The use of ultrasound guidance mitigates the influence of each of these factors. We found no evidence that the adoption of ultrasound guidance by trainees is associated with reduced proficiency in landmark-based methods. Conclusions: The use of ultrasound guidance by trainees for radial artery catheterization in critically ill children is associated with improved outcomes compared with the palpation method.