Table 2

Successful cannulation rate according to insertion technique

VariablesUltrasound-guided method, n=57* Landmark method, n=57* P valueP value
n, %, median (IQR)n, %, median (IQR)
Day 1
 Success at the first attempt23/56 (41%)18/55 (33%)0.886
 Success at the second attempt8/56 (14%)13/55 (24%)
 Success at the third attempt6/56 (11%)7/55 (13%)
 Failure at the third attempt19/56 (34%)17/55 (31%)
 % success37/56 (66%)39/56† (70%)0.840
Day 2
 Success at the first attempt5/16 (31%)6/17 (35%)1.000
 Success at the second attempt2/16 (13%)3/17 (18%)
 Success at the third attempt1/16 (06%)1/17 (06%)
 Failure at the third attempt8/16 (50%)7/17 (41%)
 % success8/16‡ (50%)10/17 (59%)0.874
Day 3
 Success at the first attempt3/9 (33%)1/6 (17%)0.536
 Success at the second attempt1/9 (11%)0/6 (00%)
 Success at the third attempt1/9 (11%)1/6 (17%)
 Failure at the third attempt4/9 (44%)4/6 (67%)
 % success5/9§ (56%)2/6§ (33%)0.608
Day 4
 Success at the first attempt1/4 (25%)0/4 (00%)0.617
 Success at the second attempt1/4 (25%)1/4 (25%)
 Success at the third attempt1/4 (25%)0/4 (00%)
 Failure at the third attempt1/4 (25%)3/4 (75%)
 % success3/4 (75%)1/4 (25%)0.486
 Global success53/54 (98%)52/55 (95%)0.618

  • Comparisons between the groups were performed using the Student or Mann Whitney test for quantitative variables and the χ² test or Fisher’s exact test for categorical variables.

  • ↵*One case lost in the UGM group, one patient in the LM group presented an unexpected clinical deterioration before the first attempt

  • ↵†One patient was successfully cannulated but with no record on the number of attempts.

  • ↵‡In UGM group, at day 2, two patients were not punctured and one patient deceased between days 1 and 2.

  • ↵§Two patients deceased between days 2 and 3 in UGM group and in LM group.