[Ultrasound-guided cannulation or by pulse palpation in the intensive care unit]

Ultrasound (US) guidance increases the success rate and decreases complications during central venous catheterisation (CVC). The benefits of US guidance in arterial catheterisation are less clear. The aim of this study is to compare the outcomes of US-guided arterial catheterisation with the traditional landmark (LM) technique in critically ill children.

A prospective multicentre study was carried out in 18 Paediatric Intensive Care units in Spain during a 6-months period. Ultrasound guided and landmark techniques were compared in terms of cannulation technical success and immediate mechanical complications.

A total of 161 procedures were performed on 128 patients (78 procedures in the US group and 83 in the LM groups). The median (interquartile range) age and weight of the cohort was 11months (2-52), and 10kg (4-17), respectively. More than half (59.6%) were male. US was used mainly in big (number of beds 11 [8-16] vs 6 [4-10], p < 0,001) and high complexity intensive care units (cardiac surgery program 76.9% vs. 25.6%, P<.001) as well as in smaller children [weight 5.7kg (3.8-13) vs 11.5kg (4.9-22.7), P<.001]. Almost half (49.7%) of the procedures were performed by an inexperienced operator (paediatric resident, or staff with less than 5years of clinical experience in the PICU), and only 24.4% had performed more than 50 US-guided vascular access procedures before the study. There were no significant differences between US and LM techniques in terms of first-attempt success (35.8% vs 33.7%, P=.773), overall success (75.6% vs 71.1%, P=.514), number of puncture attempts [2 (1-4) vs 2 (1-3), P=.667] and complications (16.6% vs 25.6%, P=.243). Adjustment by potential confounders using multivariate regression models did not modify these results. Subgroup analyses showed that US outperformed LM technique in terms of overall success (83.7% vs 62.7%, P=.036) and complications (10,8% vs 32.5%, P=.020) only when procedures where performed by less-experienced operators.

In this prospective observational multicentre study, US did not improve arterial cannulation outcomes compared to the traditional LM technique in critically ill children. US-guided arterial cannulation may offer advantages when cannulation is performed by inexperienced operators.