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Abstract: FR-PO557

Effluent Colors in Continuous Hemodiafiltration

Session Information

Category: Trainee Case Report

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Dias goncalves, Priscila, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
  • Reis, Thiago A., CDRB - Clinica de Doencas Renais de Brasilia, Brasilia, DF., Brazil
  • Freitas, Geraldo Rubens Ramos, USP, Brasilia, Brazil

Continuous venovenous hemodiafiltration (CVVHDF) is widely used as a renal replacement therapy modality on patients with acute kidney injury .It usually generates a yellow citrine outflow that is stored as effluent . Bellow we describe 2 cases of unusual effluent color changes due to special clinical situations in our center.

Case Description

Case Report 1- Red effluent fluid: An 38 year- old female patient admitted to the ICU after mitral valve replacement surgery developed Acute Kidney Injury ( AKI) . CVVHDF was attempted and on the 14th day after surgery , effluent fluid was red colored ,concomitant with the spike of CPK and the diagnosis of rhabdomyolysis .Dipstick analysis revealed the presence of hemoglobin( false positive). Microscopic evaluation of the effluent fluid was negative for the presence of red blood cells, thus excluding the possibility of rupture of the filter.Myoglobin concentration on the effluent was 1765 UI/L.
Case report 2- Green effluent fluid :An 50 year-old male patient admitted to the ICU after myocardial revascularization surgery developed AKI and CVVHDF was attempted .Due to refractory shock methylene blue was added to the vasoactive drugs arsenal and 30 minutes later the effluent fluid removed by CVVHDF was green colored.


Changes on the CVVHDF effluent color to red should alert the nephrologist to the possibility of hemolysis or dialyzer membrane compromise. Because of it’s high molecular weight and a Sieving coefficient of less than 0,1% hemoglobin is not expected in the dialysate . However myoglobin has a much smaller molecular weight and a Sieving Coefficient of 40% , therefore it should be considered as a possible cause of red dialysate.Blue colored effluent occurred most likely due to and additive effect of the methylene blue with the usual citrine yellow effluent color.