Standard-length catheters vs long catheters in ultrasound-guided peripheral vein cannulation.

Purpose: Ultrasound (US) is a useful tool for peripheral vein cannulation in patients with difficult venous access. However, few data about the survival of US-guided peripheral catheters in acute care setting exist. Some studies showed that the survival rate of standard-length catheters (SC) is poor especially in obese patients. The use of longer than normal catheters could provide a solution to low survival rate. The aim of the present study was to compare US-guided peripheral SCs vs US-guided peripheral long catheters inserted with Seldinger technique (LC) in acute hospitalized patients with difficult venous access.

Methods: This was a prospective, randomized controlled trial. A total of 100 consecutively admitted subjects in an urban High Dependency Unit were randomized to obtain US-guided intravenous access using either SC or LC after 3 failed blind attempts. Primary outcome was catheter failure rate.

Results: Success rate was 86% in the SC groups and 84% in the LC group (P=.77). Time requested to positioning venous access resulted to be shorter for SC as opposed to LC (9.5 vs 16.8 minutes, respectively; P=.001). Catheter failure was observed in 45% of patients in the SC group and in 14% of patients in the LC group (relative risk, 3.2; P<.001).

Conclusions: Both SC and LC US-guided cannulations have a high success rate in patients with difficult venous access. Notwithstanding a higher time to cannulation, LC US-guided procedure is associated with a lower risk of catheter failure compared with SC US-guided procedure.