Analysis of the optical concentration curve to detect access recirculation.

The optical blood volume curve sometimes presents either a positive or a negative rapid and reversible variation (spike) during the step of the dialysate conductivity, automatically set by the monitor for the ionic dialysance (ID) measurement. We studied whether this feature was in relation with access recirculation. Firstly, we studied if the manoeuvre of reversed position of the blood lines created the same feature in the blood volume curve.

[Performance of central catheters on the filtration yield measured by ionic dialysance ].

Certain number of dysfunctions, particularly decline of blood flow or, recirculation, can decrease the adequacy of depuration, when central catheters are used. Ionic dialysance is available on some monitors (Integra), and reflects perfectly the effective urea clearance, permits to watch any variation in the effective clearance of the depuration system due to these dysfunctions. We report on our experience in a retrospective study from 01/01/2000 to 30/11/2000 where we compared the effective clearance of depuration measured by the ionic dialysance of all the sessions of dialysis made on central catheters in our center, with the forecast clearance of sessions made in the same conditions of dialysis but with a non pathologic fistula.