Prospective Comparison of Ultrasound-Guided Versus Palpation Techniques for Arterial Line Placement by Residents in a Teaching Institution

Abstract

Background: Arterial line insertion is traditionally done by blind palpation. Residents may need multiple attempts for successful insertion, leading to longer procedure times and many failed attempts. Objective: We hypothesized that ultrasound guidance (USG) would be faster and more successful than traditional blind palpation (TBP) for radial artery line placement by residents. Methods: Patients undergoing elective surgery requiring a radial arterial line were randomized to either the USG or TBP groups. Exclusion criteria included a need for arterial line placement in an awake patient, emergent surgery, or American Society of Anesthesiologists (ASA) physical status class VI. After the induction of anesthesia, a postgraduate year 3 (PGY-3) or PGY-4 anesthesia resident placed an arterial line by either USG or TBP. Results: A total of 412 patients and 85 of 106 residents (80%) in the training program were included. The 2 groups were similar with respect to sex, weight, height, ASA class, baseline systolic blood pressure, and baseline heart rate. USG was faster than TBP (mean times 171.1 ± 16.7 seconds versus 243.6 ± 23.5 seconds, P = .012), required fewer attempts (mean 1.78 ± 0.11 versus 2.48 ± 0.15, P = .035), and had an improved success rate (96% versus 90%, P = .012). Conclusions: We found that residents using USG in an academic institution resulted in significantly faster placement of the arterial lines, fewer attempts, and fewer catheters used.