Arterial Cannula Placement in Children
Placement of an arterial cannula perioperatively in children is commonly performed for continuous hemodynamic monitoring and/or frequent blood sampling. The distal radial artery is often the preferred location, however, access at that location is not always possible. More proximal locations like the brachial, femoral, or axillary artery are associated with higher risk of injury to deep structures, hematoma formation, ischemia, and infection. While the majority of complications occur during cardiac catheterization using larger cannulae, femoral lines are now known to be associated with higher risk of complications in children.
In a retrospective single-center cohort study by Gleich et al., the rate of major complications was 0.2%, and all of these cases involved proximal femoral lines, with other placements being radial, ulnar, pedal, brachial/axillary, and a few umbilical. Notably, age seemed to correlate with risk, as the majority of complications were seen in infants and neonates.1
Kim et al. also studied distal alternatives for arterial cannula placement and found the posterior tibial artery to be an appropriate alternative in children. The diameter of this vessel is comparable to the radial artery and significantly larger than the dorsalis pedis, another vessel commonly chosen in the foot. In fact, the posterior tibial artery was found to have a larger cross-sectional area than both the radial and dorsalis pedis in this single-blind randomized controlled trial. First attempt rates were also comparable between radial and posterior tibial arteries, and these were both significantly higher than the success rate for cannulating the dorsalis pedis artery in children.2
Quan et al. performed a double-blind parallel group trial comparing two ultrasound-guided techniques, a novel acoustic shadowing technique versus the traditional out-of-plane technique and found a significantly higher first attempt rate for the novel group. Time to identification of the vessel and time to puncture were significantly lower in the novel group, indicating the acoustic shadowing technique may be a more efficient and less risky alternative.3
Taking this data into account, it appears that the posterior tibial artery would be the ideal location for cannula placement in children, especially in cases where the radial artery is inaccessible. Distal catheters are preferred to more proximal locations, and when possible, ultrasound guidance should be utilized in a manner with which the provider is most comfortable. Finally, the novel ultrasound guidance technique using acoustic shadowing should ideally be incorporated into widespread practice in pediatric anesthesiology going forward as this appears to improve the first attempt success rate significantly.
References
1. Gleich SJ, Wong AV, Handlogten KS, Thum DE, Nemergut ME. Major short-term complications of arterial cannulation for monitoring in children. Anesthesiology. 2021;134(1):26-34. doi: 10.1097/ALN.0000000000003594
2. Kim E, Lee J, Song I, Kim J, Lee W, Kim H. Posterior tibial artery as an alternative to the radial artery for arterial cannulation site in small children: A randomized controlled study. Anesthesiology. 2017;127(3):423-431.
3. Quan Z, Zhang L, Zhou C, Chi P, He H, Li Y. Acoustic shadowing facilitates ultrasound-guided radial artery cannulation in young children. Anesthesiology. 2019;131(5):1018-1024.