Measurement of Central Venous Pressure is widely practiced at the many hospitals at the present time and is accepted as a useful diagnostic test and as an aid to the effective therapy in a variety of clinical problems.
Monitoring the central venous pressure is essential in managing the surgical patients with septic. cardiogenic, or hypovolemic shock, and medical patients with renal or cardiopulmonary failure. The subclavian venipuncture with catheterization for the measurement of CVP is also useful for the prolonged or continuous intravenous administration of fluids, for total parenteral hyperalimentation and for the intravenous route in eases of peripheral, vascular collapse.
The subclavian vein is located within the costo-clavicular-scalene triangle and is approximately .3 to °4 centimeters long,. 1 to 2 centimeters in diameter in`the adults..- The patient is placed ´in a :supine and slightly Trendeleliburg position. The skin is prepped with iodine and alcohol meticulously and draped to expose the ´clavicle and suprasternal notch. The junction of the middle and medial thirds of the clavicle is located and the area of the skin about 0.5 to 1.0 cm below this point is infiltrated with local anesthetics. A 5 to 10 cc syringe filled with normal saling is attached to a 14 to 15 gage needle of 7-8 cm length.
Through the anesthetized skin the needle is advanced with its tip directed toward the suprasternal notch or posterior superior angle of the medial end of clavicle. It is important to maintain the negative pressure while advancing the needle and the free flow of blood is observed in the syringe when the needle is in the vein The needle is further advanced 2 to 3 mm and with the catheter held secure, the needle is removed. The catheter is fixed to the skin with two silk sutures to prevent the accidental withdrawal. The catheter is connected to a 3-way stopcock to the intravenous solution.
The pressure is measured with manometer with its zero point at the level of midaxillary line. The normal CVP in the adult is between 60~120 mm H20.
The complications of subclavian venipuncture and catheterization include cellulitis, sepsis, pneumothorax, hemothorax, hydrothorax, air embolism, catheter embolization, thrombosis, hemorrhage, injury to the vessels and nerve, perforation of myocardium, and arrhythmia.
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