Abstract: A medical needle for withdrawal of blood from a patient or for insertion in medicinal containers in which the end of a needle extending from the body of a syringe is provided with one or more marks at its end region to indicate the depth of penetration of the needle below the skin surface of a patient in a given site so that the depth of penetration can be indicated as well as the degree of withdrawal of the needle in such instances as when the needle is required to be partially pulled out maneuvered below the skin to seek an artery for withdrawal of blood. In addition, the end of the needle is provided with coloring and a marking such that it is more visible than the bare stainless steel needles of conventional type thereby assisting in prevention of accidental needle sticks in either the technician or the patient.

Abstract: A light beam leveling device and method utilizable particularly in hemodynamic cardiac monitoring of patients in which a pressure transducer is required to be leveled with the tip of a catheter placed at the heart of a patient. The light beam device, preferably a laser, is placed at the transducer and is raised and lowered therewith relative to a reference point on the patient corresponding to the level of the tip of the catheter. When the laser beam is projected horizontally as established with associated bubble level means and is directed so as to cause a reflection directly at the reference point, the transducer is assured thereby to be at the level of the catheter tip in the patient. A transparent cylindrical bar at the tip of the laser through which the laser beam passes causes a line of light to be projected at right angles to the orientation of the bar. An associated protractor permits selection of the desired angle of orientation of the line of light projected from the laser.