Abstract: A supporting board or like structure designed to be attached to the limbs including arms, legs, etc. of a patient to facilitate the securement of an I.V. catheter assembly to the patient and the immobilization of the catheter and the I.V. tubing to guard against inadvertent disengagement or removal of the catheter from the supported limb. A substantially rigid material base includes an absorbent material covering and a portion projecting outwardly from a transverse segment of the supporting base wherein the overall shape, structure and dimensioning of the board as well as the outwardly extending projection reduces problems relating to the prolonged immobilization of the limb.