This methodological research aimed to identify the extent to which tourniquets can interfere in the visualization and characterization of peripheral vein width. Pictures (forearm/ hand) were assessed for visualization and width. Three evaluators of the above mentioned criteria unanimously agreed on 19 picture pairs. These pictures (with and without tourniquets) were presented in pairs to 61 intensive care nurses, who assessed the changes between both, using an 11-point numerical scale (zero = absence of visual alteration and 10 = maximum improvement of visualization). The data submitted to factor analysis evidence that, in 63.5% of the facts, the visualization of the blood vessels improved (>50%) after the use of the tourniquet; the pictures assessed as showing no alteration of the visualization mostly picture veins of difficult visualization and less width. The previous characterization of the vein interfered in terms of caliber and visualization and the use of the visual criterion (pictures) may have interfered in the assessments.
Nursing; Blood vessels; Tourniquets; Nursing assessment