HDCN Article Review/Hyperlink

Suhocki PV, COnlon PJ, Knelson MH, Harland R, Schwab SJ

Silastic cuffed catheters for hemodialysis vascular access: Thrombolytic and mechanical correction of malfunction

Am J Kidney Dis (Sep) 28:379-386 1996

The authors present their experience with the use of silastic cuffed double lumen hemodialysis catheters (Perm-Cath(R) and others) at the Duke University hemodialysis facilities. Over a 3.5 year period, 121 such catheters were placed in 88 patients, for definitive access in 31% and temporary-intermediate use (over 3 but less than 14 weeks) in 69% of the patients. Notably, the subclavian vein was used in only 4% of cases, with the internal jugular vein being the preferred site (60% Rt, 22% Lt).

There were 163 incidents of catheter malfunction (QB < 300 cc/min on 2 consecutive occasions, or < 200 cc/min once), with a 74% success rate with the standard urokinase protocol (5000 U/port). Failure of urokinase led to contrast imaging in 40 cases, which revealed catheter encasement by a fibrin sheath in 38. The authors describe a radiologic procedure using a nitinol gooseneck snare whereby the fibrin sheath was successfully removed in 36 of these. Central vein stenosis or thrombosis was not systemically studied but did not appear to be common.

Only 73% of the catheters achieved a consistent QB of 400 cc/min. Temporary catheters fulfilled their intended purpose of use up to 14 weeks, whereas the permanent ones had 51% 1 year use life, well under the 50% 3 year use life of PTFE grafts in the authors' hands. Only 4% of "temporary" catheters were removed for infection, while 54% of permanent one were removed for that reason.

Comment: Angioaccess remains the Achilles heel* of hemodialysis. With an aging ESRD population and the increased prevalence of diabetes and peripheral vascular disease in our patients, it is not surprising that our technical advances are often insufficient to keep up with their needs. This paper is an excellent review of dialysis access experience with cuffed venous catheters. As the authors have published extensively on angioaccess, their results should be viewed as representing the current state of the art on the use of these catheters. Even in their hands, 1 year catheter failure is nearly 50%; despite excellent results with catheter placement and fibrin sheath removal, the problem of catheter loss to infection remains to be solved.

These catheters are clearly suboptimal in terms of blood flow; it would have been interesting to note what Kt/Vs were achieved in the group in which the Perm-Cath was used as the definitive access. I also would be curious as to the incidence of switching the A and V ports to achieve some dialysis rather than none in a given session. One minor point regarding the stratification to temporary vs. permanent use: it seems that the authors assigned the "trial of hemodialysis..." patients to the permanent group; it would seem that these should be viewed as temporary, inasmuchas if the patient were to respond to hemodialysis, then an evaluation for permanent access would proceed as usual.

We see a group of patients who have subclavian stenoses due to prior percutaneous catheter use, forcing us to use the IVC as a last resort for Perm-Cath placement for hemodialysis. It would be interesting to learn if the authors have used that approach, and what results they obtained. Overall, this is a very instructive report on the current status of Perm-Cath type catheters. (James A. Sondheimer MD, Wayne State University, Detroit, MI)

*(Note: while typing this, I made the Freudian slip of writing "hell" instead of "heel"; perhaps I should have let the oroginal wording stand!)