Ultrasound guidance allows faster peripheral IV cannulation in children under 3 years of age with difficult venous access: a prospective randomized study.

OBJECTIVES: Ultrasound-guided peripheral venous access (USG-PIVA) presents many advantages over the reference 'blind' technique in both adults and children in emergency situations. AIM: To compare USG-PIVA with the blind technique in children <3 years undergoing general anesthesia. METHODS: After obtaining the approval of the ethics committee and informed consent from the parents, we included all children <3 years scheduled to undergo general anesthesia [surgery, magnetic resonance imaging (MRI)], who presented difficult venous access. The children were randomized into two groups: the US group (USG-PIVA) and the B group (blind). The primary endpoint was time to cannulation (from tourniquet placement to successful IV cannulation), compared between USG-PIVA group and B group by intention-to-treat analysis. Secondary outcomes were success rate at the first puncture, number of punctures, and diameter of the catheters. Cannulations requiring >15 min were considered as failures. In case of failure in group B, USG-PIVA was attempted for a further 15 min. RESULTS: Twenty children were included in each group. Groups were comparable for sex, age, and BMI. Significant differences were observed in median time to cannulation (63.5 s vs 420.5 s, USG-PIVA vs B respectively, P < 0.001); median number of punctures (1 vs 2.5, USG-PIVA vs B, P = 0.004); and success rate at first cannulation (85% vs 35%, USG-PIVA vs B, P = 0.0012). In contrast, overall success rate did not differ significantly between groups (90% vs 85%, USG-PIVA vs B, P = 0.63). CONCLUSIONS: Ultrasound-guided peripheral venous access leads to faster peripheral IV access and should therefore be recommended in children presenting with difficult venous access.

Diffusion tensor tractography in mesencephalic bundles: relation to mental flexibility in detoxified alcohol-dependent subjects.

Components of the corticocerebellar circuit and the midbrain individually play a central role in addictive processes and have been associated with altered volumes and impairment of cognitive flexibility in alcohol-dependent subjects. The microstructure of white matter bundles composing the corticocerebellar network and passing through the midbrain was studied using diffusion tensor imaging in a group of detoxified alcohol-dependent men (n=20) and a group of healthy men (n=24). The relationship between properties of these white matter bundles and cognitive flexibility performance was investigated in alcohol-dependent subjects. Bundles connecting two regions of interest were analyzed using a fiber-tracking quantitative approach, which provided estimates of the fractional anisotropy and the apparent diffusion coefficient, as well as the number of tracked fibers normalized by the volume of regions of interest. Within the bundles running between the midbrain and pons, a mean of 18% fewer fibers per unit volume were tracked in alcohol-dependent men than in healthy controls. In addition, the normalized number of these fibers correlated with the performance in the Trail-Making Test part-B. Even though the alcohol-dependent subjects were detoxified and apparently neurologically intact, their earlier excessive use of alcohol seems to be associated with altered neural microstructure of mesencephalic white matter bundles, which may contribute to their cognitive flexibility impairment.