Comparison of ultrasound guided long axis and short axis approach for radial artery cannulation in adult patients undergoing elective surgery under general anaesthesia

There can be two techniques for radial artery cannulation under ultrasound guidance, one being the short axis out-of-plane (SA-OOP) approach and the other being long axis in-plane (LA-IP) approach. We are conducting this study because there are incongruous opinions regarding the recommended approach for ultrasound guided radial artery cannulation. To compare ultrasound guided long axis and short axis approach for radial artery cannulation in adult patients undergoing elective surgery under general anaesthesia. Primary objective of our study was to compare the first attempt success rate. Secondary objective was to compare successful cannulation time, number of attempts and complications. 110 patients of ASA1 and ASA2 class of age 18-70 years, scheduled for elective surgery under general anaesthesia requiring radial artery cannulation were randomized into group I (long axis view) and group II (short axis view) using sealed envelope method. Statistical package for social Sciences (SPSS) version 21.0 was used for statistical analysis after entering data into Microsoft excel spreadsheet. The first attempt success rate was comparable between long axis and short axis, 81.82% vs 78.18% with a p value=0.634. Mean ± SD of time taken in seconds for successful cannulation in short axis group was 35.11 ± 19.79 which was significantly higher as compared to long axis group 25.51 ± 21.89 with p value=0.018. Ultrasound guided long axis technique was analogous to ultrasound guided short axis technique with regard to overall and first attempt success rate, number of attempts and complications. However time taken for cannulation of the radial artery in long axis approach is lesser.