Duration of catheterisation in successful cases
| Duration (s) | Group D | Group N | P value |
| Localisation | 6.92±4.21 | 8.44±6.59 | 0.150 |
| Insertion | 13.67±17.01 | 10.35±13.03 | 0.254 |
| Cannulation | 26.19±19.16 | 35.68±18.72 | 0.010 |
| Overall | 46.78±27.09 | 54.47±23.79 | 0.117 |
There was no statistical difference in the incidence of complications between the two groups (6.7% in group D, 8.3% in group N, p=1.000).
Subgroup analysis of cannulation time in 110 successfully catheterised patients is described in the online supplemental table S2.