Q: What port should be used to measure central venous pressure with a triple-lumen catheter?
A: Kristine J. Peterson, RN, MS, CCRN, CCNS, replies:
Central catheters are common in acute and critical care areas. Because of the complexity of the care for these patients, many central catheters have multiple lumens. Typically, the distal lumen opens at the tip of the catheter, while the other lumen(s) open slightly proximal to this on the sides of the catheter. Is a central venous pressure (CVP) measurement obtained from any one of the 2, 3, or 4 lumens of these catheters different from the measurement obtained from any of the other lumens? Very little direct evidence is available to guide us on this question. What little we know comes from studies on different types of catheter placement. Only 1 study specifically addressed the influence of port site on CVP measurements.
In a laboratory study...