ObjectivesCatheter misplacement into the internal jugular vein (IJV) often occurs during pediatric subclavian vein (SCV) catheter placement. The aim of this study was to investigate whether an innovative method of occluding the IJV by applying temporary pressure at the IJV just above the clavicle could help prevent its occurrence. DesignThis is a randomized controlled trial. SettingsThis study was conducted in a single medical center. ParticipantsOne hundred and seventy-eight children undergoing SCV catheterization were recruited. InterventionsChildren were randomly assigned to the traditional group (unassisted placement of the guidewire) and the innovative group (temporary pressure on the IJV just above the clavicle to occlude the IJV during placement of the guidewire). Measurements and Main ResultsThe primary outcome was the incidence of guidewire misplacement into the IJV at the time of first placement. Secondary outcomes included the total number of attempts and the total time of guidewire placement. The incidence of misplacement at the first attempts was reduced from 18.06% in group C to 6.67% in group I (P=0.04). The total number of guidewire entered the IJV in group I was less than in group C [group C vs. group I = 24/96 vs. 7/82, P=0.005]; the total time of guidewire placement was reduced from 35.00s (18.25s, 54.00s) in group C to 26.00s (17.00s, 38.00s) in group I, (P=0.03). ConclusionsTemporary pressure at the IJV just above the clavicle to occlude the IJV during placement of the guidewire helps prevent inadvertent placement of the guidewire into the IJV.