Hand–eye coordination and ergonomics are important for the success of delicate ultrasound-guided medical procedures. These can be improved using smart glasses (head-mounted display) by decreasing the head movement on the ultrasound screen. The hypothesis was that the smart glasses could improve the success rate of ultrasound-guided pediatric radial arterial catheterization.


This prospective, single-blinded, randomized controlled, single-center study enrolled pediatric patients (n = 116, age less than 2 yr) requiring radial artery cannulation during general anesthesia. The participants were randomized into the ultrasound screen group (control) or the smart glasses group. After inducing general anesthesia, ultrasound-guided radial artery catheterization was performed. The primary outcome was the first-attempt success rate. The secondary outcomes included the first-attempt procedure time, the overall complication rate, and operators’ ergonomic satisfaction (5-point scale).


In total, 116 children were included in the analysis. The smart glasses group had a higher first-attempt success rate than the control group (87.9% [51/58] vs. 72.4% [42/58]; P = 0.036; odds ratio, 2.78; 95% CI, 1.04 to 7.4; absolute risk reduction, –15.5%; 95% CI, −29.8 to −12.8%). The smart glasses group had a shorter first-attempt procedure time (median, 33 s; interquartile range, 23 to 47 s; range, 10 to 141 s) than the control group (median, 43 s; interquartile range, 31 to 67 s; range, 17 to 248 s; P = 0.007). The overall complication rate was lower in the smart glasses group than in the control group (5.2% [3/58] vs. 29.3% [17/58]; P = 0.001; odds ratio, 0.132; 95% CI, 0.036 to 0.48; absolute risk reduction, 24.1%; 95% CI, 11.1 to 37.2%). The proportion of positive ergonomic satisfaction (4 = good or 5 = best) was higher in the smart glasses group than in the control group (65.5% [38/58] vs. 20.7% [12/58]; P <0.001; odds ratio, 7.3; 95% CI, 3.16 to 16.8; absolute risk reduction, –44.8%; 95% CI, –60.9% to –28.8%).


Smart glasses-assisted ultrasound-guided radial artery catheterization improved the first-attempt success rate and ergonomic satisfaction while reducing the first-attempt procedure time and overall complication rates in small pediatric patients.

Editor’s Perspective
What We Already Know about This Topic
  • Although ultrasound is becoming commonplace to guide arterial cannulation in children, there is still an appreciable failure to succeed on the first pass
  • Head-mounted displays are a new technology finding novel applications in medical practice
What This Article Tells Us That Is New
  • In a randomized controlled trial comparing radial artery cannulation in children, a head-mounted display, which projects the ultrasound screen in front of the operator’s eye, had a greater first-attempt success rate and shorter times to cannulation compared to conventional ultrasound use