Abstract: Objective To explore the difference of ultrasound-guided radial and ulnar artery catheterization by measuring the inner diameter and depth of the bilateral radial and ulnar arteries in infants. Methods A total of 120 infants selected for elective surgery in our hospital underwent general anesthesia were included in this study. The depth, inner diameter and anatomical variation of the three mark points of bilateral radial and ulnar arteries were recorded. At the same time, the height, body weight, time of abstaining from drinking and fasting, the mean arterial pressure (MAP), heart rate (HR) and body temperature of children were recorded. Results There were no significant differences in the depth and inner diameter of radial artery and ulnar artery measured by ultrasound between the left and right forearms. Both radial arteries were superficial than ulnar arteries (P＜0.05). The depth of the second measurement mark point of radial and ulnar artery was deeper than that of the first measurement mark point, and the third measurement mark point was deeper than that of the second measurement mark point (P＜0.05). There were no significant differences in internal diameters of radial and ulnar arteries between all measurement mark points. The depth of bilateral radial and ulnar arteries was negatively correlated with age, height, body weight and MAP, and positively correlated with HR (P＜0.01). The internal diameters of bilateral radial and ulnar arteries were positively correlated with age, height, body weight and MAP, and negatively correlated with HR (P＜ 0.01). Conclusion The inner diameters of radial and ulnar arteries in infants under ultrasound are similar. The ultrasoundguided arterial puncture of radial and ulnar arteries in infants has selective value, and which is worthy of further study.

Key words: radial artery, ulnar artery, ultrasonography, arterial puncture, infants