LETTERS TO THE EDITOR
Central venous catheterization is an important means of long-term vascular access in a variety of clinical situations. The most common cause of early catheter malfunction is incorrect placement of the catheter tip during insertion, and it is usually detected by a chest radiograph (1).
Malposition of a central venous catheter is more common with the subclavian approach. The misplacement is often cephalad into the ipsilateral internal jugular vein (IJV), although the catheter tip may also be placed in the contralateral IJV or the brachiocephalic vein (1). This may increase the risk of chemical or bacterial thrombophlebitis in addition to distorting central venous pressure (CVP) measurement (2). Aberrant locations of the catheter in the azygous and superior intercostal veins have also been reported (1).
We describe a method for rapid clinical diagnosis of a misplaced subclavian vein catheter. Both sides of the neck, including the supraclavicular area, are included in the skin preparation for the procedure. After inserting the subclavian venous catheter, it is connected to the pressure transducer so that the CVP wave form and value are displayed on the monitor screen. After the CVP value is noted, firm pressure is applied on the ipsilateral IJV in the supraclavicular region for approximately 5–10 s. Any rise in the CVP value above the baseline means the catheter tip has entered the ipsilateral IJV, as occluding the IJV impedes the venous return and raises the CVP distal to the occlusion. If there is no change in the CVP, the misplacement of the catheter tip in the ipsilateral IJV can be safely excluded. Next, the same maneuver is repeated on the contralateral side. However, a decrease in the CVP value may also occur on this side, suggesting that the catheter tip is in the brachiocephalic vein, because occlusion of the IJV causes a drop in the CVP proximal to the occlusion.
Although the chest radiograph is still the most commonly used diagnostic tool to detect misplacement of a central venous catheter, our method is simple, quick, and immediately applicable with no extra cost. The patient is spared an extra exposure to radiography, which has to be repeated after any repositioning. The method described has limitations in patients with raised intracranial pressure because of obvious reasons, and may not help diagnose the misplacement into veins other than the IJV and the contralateral brachiocephalic.
Jyotish C. Pandey MD
Prakash K. Dubey MD
1. Boardman P, Hughes JP. Pictorial review: radiological evaluation and management of malfunctioning central venous catheters. Clin Radiol 1998; 53:10–6.
2. Conces DJ, Holden RW. Aberrant locations and complications in initial placement of subclavian vein catheters. Arch Surg 1984; 119:293–5.