Subcutaneous Nitroglycerin to Prevent Radial Artery Occlusion in Children

The primary objective of the study is to evaluate the vasodilative effect of subcutaneous nitroglycerin to prevent radial arterial occlusion(RAO) after removal of the radial arterial catheter in pediatric patients. The hypothesis of this study is that subcutaneous nitroglycerin will decrease the incidence of radial arterial occlusion after radial arterial catheter removal in pediatric patients by increasing the radial artery size. This is a single-center, double-blind, randomized, placebo-controlled study comparing the effect of subcutaneous nitroglycerin and saline on radial artery cannulation and catheter removal in pediatric patients. Prior to the procedure, each patient will be randomized into either the control arm, saline, or the study arm, nitroglycerin.