HDCN Article Review/Hyperlink

Petersen J, Kang MS, Yeh I

The site of injection affects erythropoietin levels during dialysis

ASAIO J (Jul) 42:263-265 1996

EPO, when given intravenously, is usually given as a bolus into the venous line at the end of dialysis. The venous injection can be via a sampling port which is between the dialyzer and drip chamber (Cobe Centry 3) or between the venous drip chamber and patient (Fresenius lines). An alternative site of injection is into the venous drip chamber itself. The authors compared blood EPO levels after injecting their patients with EPO one week via the sampling port, and one week via the drip chamber. Both Cobe and Fresenius lines were used.

When the EPO was given via the Cobe lines, it made no difference if it was injected into the sampling port or into the drip chamber itself. Both methods resulted in a prompt increase in plasma EPO levels. However, with the Fresenius lines, a good plasma EPO increase was seen after injection into the sampling port, but only a minimal increase was seen when EPO was injected directly into the drip chamber. The authors suggest that the lack of rise in plasma EPO after injection into the drip chamber directly is due to trapping of the injected EPO at the top of the blood/air interface, which apparently occurs to a lesser extent with the cartridge type of drip chamber found with the Cobe lines. They suggest that injection of EPO into the drip chamber via Fresenius lines might be a covert cause for EPO "resistance".

Comment: With the high costs of EPO, this article has an extremely high clinical and cost relevance. (John T. Daugirdas, M.D., University of Illinois at Chicago)