Table 2 Comparison of procedure related data
|  | Landmark- guided group n = 40 | Ultrasound- assisted group n = 40 | P value | 95% CI of differences (%) |
|---|---|---|---|---|
First pass success, n (%) | 8 (20) | 28 (70) | < 0.001 | (31.1 to 68.9) |
Success within 2 passes, n (%) | 16 (40) | 33 (82.5) | < 0.001 | (23.3 to 61.7) |
First attempt success, n (%) | 17 (42.5) | 34 (85) | < 0.001 | (23.6 to 61.4) |
Success in 2 attempts, n (%) | 34 (85) | 38 (95) | 0.264a | (−3 to 23) |
Number of attempts | 2 [1 to 2] | 1 [1 to 1] | < 0.001 |  |
Number of passes | 3 [2 to 4] | 1 [1 to 2] | < 0.001 |  |
Locating time(s) | 32.5 [21.3 to 40.8] | 337.5 [300.0 to 403.8] | < 0.001 |  |
Puncture time(s) | 320.0 [223.3 to 583.0] | 227.5 [170.0 to 340.0] | 0.003 | Â |
Total time(s) | 440.3 ± 240.1 | 608.2 ± 196.9 | 0.001 |  |
Patients’ satisfaction;4–5 | 26 (65.0%) | 36 (90.0%) | 0.007 | (7.5 to 42.5) |