Nam C. Yu MD, Presenter: Nothing to Disclose

Peter Huy Pham BS, Abstract Co-Author: Nothing to Disclose

Deborah Bolton, Abstract Co-Author: Nothing to Disclose

Jessica Wallace, Abstract Co-Author: Nothing to Disclose

Steven Satish Raman MD, Abstract Co-Author: Nothing to Disclose

David Shin-Kuo Lu MD, Abstract Co-Author: Research Consultant, Siemens AG

To determine the feasibility of power injection through several commonly encountered central venous catheters.

Using a pressure and flowrate controlled power injector (EmpowerCT, E-Z-EM), multiple in vitro injections of iohexol 350 were performed through the following catheters: triple lumen CVC, dual lumen TPN line, Hickman, single- and multi-lumen PICCs, and ports. Injections only through extention coils without an attached catheter were also performed to infer the proximal resistance (hence pressure drop) during an actual catheter injection. Injector pressure was recorded as a function of time during each injection. Steady-state injector pressures were also plotted as a function of flowrate which was incrementally increased until catheter damage or achievement of maximal injector pressure (300 PSI).

A linear pressure-flowrate relationship was noted through extention coil, with slope ("resistance") of 38 PSI•sec/cc. The pressure needed to maintain a given flowrate increased variably from this baseline depending on the attached catheter's length and, more dramatically, lumen size. The pressure-flowrate linearity was disrupted at high pressures, associated with visible structural changes of the catheter, including grossly visible diffuse luminal distention, fusiform aneurysm, or frank rupture. Tolerated pressure threshold varied drastically among catheters of the same class (e.g., silicone vs. polyurethane PICCs) or even between different lumens of the same catheter, with maximal flowrates ranging as low as <0.5 cc/sec to as high as 5 cc/sec. No catheter damage was seen when the injector pressure less the expected pressure drop across the extention coil remained within manufacturer specified limits.

The extensive variety of central venous catheters in clinical use precludes a simple, blanket policy regarding safe power injection. Simple fluid dynamics concepts, however, can aid in practical application of manufacturer specified pressure limits to avoid catheter damage.

Customized injection parameters are recommended for a given catheter based on specified pressure limits. Some catheters, such as silicone PICCs, generally should not be used for power injection.

Yu, N, Pham, P, Bolton, D, Wallace, J, Raman, S, Lu, D, Power Injection of Contrast Material Through Various Central Venous Catheters: An in Vitro Study.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4441999.html