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Ultrasound-guided short-axis out-of-plane vs. long-axis in-plane technique for radial artery catheterization: an updated meta-analysis of randomized controlled trials.

OBJECTIVE
Short-axis out-of-plane (SA-OOP) and long-axis in-plane (LA-IP) are the two major approaches used in ultrasound (US)-guided radial arterial catheterization. Nevertheless, their efficacy and safety remain controversial. Therefore, this meta-analysis aimed at comparing the two approaches for radial arterial catheterization.


MATERIALS AND METHODS
The PubMed, Embase, and Cochrane Library databases were searched for relevant articles published from database inception until December 2020. We selected randomized controlled trials comparing the short- and long-axis methods for US-guided radial artery catheterization. The results were analyzed using RevMan software to determine the adequacy and conclusiveness of the available evidence.


RESULTS
Six studies (725 patients) ultimately met the inclusion criteria. No significant difference was observed between the SA-OOP and LA-IP approaches for US-guided radial artery catheterization (relative risk [RR], 0.99; 95% confidence interval [CI], 0.96-1.03; p =0.61; I2=0%). The first-attempt success rate was similar between the two groups (relative risk [RR], 1.02; 95% CI, 0.79-1.32; p =0.90; I2=87%). The incidence of hematoma formation was similar between the two groups (RR, 1.91; 95% CI, 0.66-5.56; p =0.24; I2=77%).


CONCLUSIONS
The SA-OOP approach does not increase the total or first-attempt success rate of radial artery catheterization using the LA-IP approach. More highly powered well-designed trials are needed to evaluate additional outcomes.