Influencing Factors to the Filter Life on Continuous Venovenous Hemodiafiltration without Anticoagulantion

Han, Young Mi; Im, Eun Young; Chang, Jai Won; Lee, Eun Hee; Kim, Mi Hye; Yang, Won Seok; Kim, Soon Bae; Lee, Sang Koo; Park, Su Kil; Park, Jung Sik

Abstract

BACKGROUND
Continuous venovenous hemodiafiltration (CVVHDF) is advantageous in ARF patients with the unstable emodynamics and multiorgan failure. However, use of anticoagulation is sometimes hampered by their concurrent bleeding tendency. We performed the retrospective analysis to investigate the factors that could influence on the filter life. METHODS: The patients on CVVHDF without anticoagulation who required exchange of filter 8 times or more due to clotting were included. We measured filter life, clotting time, hemoglobin, platelet count, blood flow rate, dialysate flow rate, replacement fluid flow rate and blood pressure just before the initiation of every filter. We also measured mechanical pressures relevant to the filter, such as access pressures, filter pressure, return pressure and transmembrane pressure (TMP) within the last 6 hours before termination of every filter. RESULTS: Twenty-three patients (age 57+/-16, M: F=19: 4) showed the median filter life of 9 hours 20 minutes. The filter life was not influenced by the included variables. TMP significantly increased every hour during the last 6 hours before the end of filter life (p<0.01). When TMP was greater than 120 mmHg, TMP significantly increased every hour thereafter and CVVHDF was terminated within 4 hours. CONCLUSION: This study suggested that the possibility of filter clotting should be suspected when TMP is greater than 120 mmHg in the setting of CVVHDF without anticoagulation.