Short- vs long-axis approach to ultrasound-guided peripheral intravenous access: a prospective randomized study

The objective of the study was to determine if the short-axis approach and long-axis approach to ultrasound-guided peripheral intravenous access (USGPIV) differ in success rate, catheter insertion time, and number of needle sticks.

A convenience sample of emergency department patients aged 18 to 65 years with difficult IV access (2 or more failed landmark attempts) was prospectively randomized to short-axis or long-axis USGPIV. Time from skin puncture to catheter insertion (insertion time) and number of needle sticks were recorded. Number of needle sticks and insertion time were compared using Mann-Whitney U tests.

Forty subjects were enrolled; 20 were randomized to the short-axis and 20 to the long-axis approach. Success rate was 95% (19/20; 95% confidence interval, 85%-100%) in the short-axis group compared with 85% (17/20; 95% confidence interval, 69%-100%) in the long-axis group. All 3 subjects with failed IV placement in the long-axis group had successful rescue USGPIV placement in short axis. Median insertion time was 34 seconds (interquartile range, 35 seconds) for the short-axis group compared with 91 seconds (interquartile range, 59 seconds) for the long-axis group (P = .02). Mean number of needle sticks was 1.5 (±SD 0.7) in the short-axis group compared with 1.4 (±SD 0.7) in the long-axis group (P = .82).

Short-axis USGPIV technique required less insertion time than the long-axis technique. Success rate was higher in the short-axis group, but this difference was not statistically significant. However, all of the failed IVs in the long axis were rescued successfully in short axis.