The Study Of Regional Citrate Anticoagulation In Continuous Veno-Venous Hemofiltration

Objectives:To study the safety and effect of RCA in continuous veno-venous hemofiltration (CVVH).Methods:Fourteen patients were treated by CVVH, they were treated 34 times. Simplify anticoagulation protocol, 4% sodium citrate is added in the replacement fluid. The citrate replacement fluid was infused proximal to the filter 3L/h or 2L/h,while ionized calcium and ionized magnesian are infused postfilter or by venous pump from peripheral veins. The doses of sodium citrate: 4% sodium citrate 150ml/h for patients weighing less than 50kg;4% sodium citrate 170ml/h for patients weighing 50-65 kg;4% sodium citrate 190ml/h for patients weighing over 65kg.Observing closely the patients'situation during treatment. Monitoring of BUN,Scr,PT,APTT,TT,FIB,Serum Na+,Mg2+,Cl-,K+,serum ionized calcium(Ca2+),total calcium as well as complete blood-gas analysis at the beginning and during the treatment, adjusting the infusing rate of sodium citrate and calcium. FUN/BUN ratio were measured every 4 h during the treatment.Results:1. There were 34 cases in the treatment, altogether 544 hours. The hemofilter life span was 6-28 hours, 14.79±5.98 hours on the average.2. The prefiler Ca2+ level decreasing of 8 patients was more than 0.1mmol/l (7 of them happened within 4 hours after the treatment began). The prefiler Ca2+ level of 7 patients were rectified after adjusting treating plans. The treatment one patient with hypoxemia was discontinued because of serious complication. None of the patients appeared with hypernatremia or metabolic alkalosis during the RCA. No significant bleeding events attributed to RCA.3. No markedly charges of PT,APPT,TT in postfliter blood after sodium citrate infusion.4. The significant decreasing of Ca2+,Mg2+ concentration and significant increasing of the negative value of base excess in postfliter blood were detected after sodium citrate infusion.5. 34 cases were treated by RCA, the first 20 cases by Ca2+ infused postfilter,8 of them appeared clotting in venous chamber. No clotting in venous chamber was detected after the calcium infusion way was changed by peripheral veins.Conclusion:1. RCA is of good treating effect in CVVH. The suitable doses of citrate anticoagulation have closed relationship with patients'body weight.2. The simplified anticoagulation protocol by adding sodium citrate replacement fluid can be applied safely in replacement fluid>2L/h of CVVH and it can completely avoid the complications of hypernatremia and metabolic alkalosis caused by sodium citrate anticoagulation.3. PT,APTT and TT can not be used as monitoring indexes of sodium citrate anticoagulation treating effect.4. The ionized magnesian concentration in extracorporeal circulation is markedly decreased after the infusion of sodium citrate. But it is unnecessary to raise the ionized magnesian concentration in replacement fluids in citrate anticoagulation treatments.5. It should be careful to those patients with hypoxemia when they are treated by citrate anticoagulation because there maybe serious complications.6. The complications of citrate anticoagulation often happen within 4 hours after the treatment.7. During RCA, it is more reasonable to have calcium replenishment from peripheral veins than from postfilter.