The Use of Regional Citrate Anticoagulation Continuous Venovenous Hemofiltration in Extracorporeal Membrane Oxygenation

Patients on extracorporeal membrane oxygenation (ECMO) frequently requires continuous renal replacement therapy (CRRT). Additional anticoagulation for the CRRT circuit is usually not employed, but this may increases the risk of clot embolization, which shortens oxygenator lifespan and increases patient's risk. We report our experience on the use of regional citrate anticoagulation continuous venovenous hemofiltration (RCA-CVVH) connected to an ECMO circuit, which could be useful during low heparin or heparin-free ECMO situations. Regional citrate anticoagulation continuous venovenous hemofiltration was performed using AK200US machine with a blood flow of 150 ml/min, Acid Citrate Dextrose Solution prefilter infusion at 240 ml/hr, ultrafiltration rate of 2,040 ml/hr, and postdilutional online generated replacement fluid infused as appropriate. The circuit was aimed to run for 30 hrs. From May 2009 to May 2013, 63 patients received ECMO and 29 received RCA-CVVH. The median total CVVH time was 131 hrs (interquartile range [IQR]: 61-224 hrs), and hemofilter life was 27.2 hrs (IQR: 25.7-28.5 hrs). No hemofilter or oxygenator was changed because of clotting. Their hospital mortality was 27.6%. There were eight patients, who were judged to be too sick for anticoagulation, received predilution CRRT during the same period. Their hospital mortality was 75%. In conclusion, online postdilutional RCA-CVVH connected to an ECMO circuit is a feasible, safe, and effective CRRT technique.