A mathematical estimation for quantified calcium supplementation during intermittent hemodialysis using regional citrate anticoagulation. Issue 6 (11th January 2022)

• Record Type: Journal Article
• Authors: Bi, Xiao; Zhang, Qi; Zhuang, Feng; Ding, Feng
• Is Part Of: Artificial organs. Volume 46:Issue 6(2022)
• Page Start: 1122
• Page End: 1131
• Publication Date: 2022-01-11
• Subjects: calcium -- clearance -- creatinine -- intermittent hemodialysis -- phosphate -- regional citrate anticoagulation; Artificial organs -- Periodicals; 617.956
• DOI: 10.1111/aor.14164
• Languages: English
• ISSNs: 0160-564X

Abstract

Abstract: Background: Regional citrate anticoagulation has been recommended as an alternative of anticoagulation for patients at high risk of bleeding undergoing intermittent hemodialysis. Precise calcium supplementation is important for the safety of regional citrate anticoagulation. In this study, we aimed to develop a possible method to optimize calcium supplementation for regional citrate anticoagulation in intermittent hemodialysis. Methods: The investigation consisted of a pilot study and a validation study. 18 patients undergoing intermittent hemodialysis anticoagulated by citrate, and six types of filters were included in the pilot study. The ionized calcium levels were monitored and maintained in the targeted range. Calcium‐free dialysate was used in the study. After linear regression analysis of the clearance of non‐protein bound calcium and calculating the ratio of the non‐protein bound calcium concentration to total calcium concentration, we developed a mathematical model for estimation of extracorporeal circuit calcium removal. Another 8 maintenance hemodialysis patients (12 sessions) were enrolled in the validation study to validate the new version of the calcium supplementation approach. Results: In the pilot study, positive correlations were found between the clearance of non‐protein bound calcium and the hematocrit‐adjusted clearance of creatinine and phosphate given in the dialyzer leaflet ( R 2 = 0.31, p = 0.0165). The ratio of the non‐protein bound calcium concentration to total calcium concentration at the pre‐filter point after infusion of citrate were constant about 0.75. In the validation study, we found that the systemic ionized calcium levels were stably maintained in the safe range and no filter clotting occurred during the hemodialysis when we used the new model of calcium supplementation. Conclusions: We developed a possible method to quantify calcium supplementation for intermittent hemodialysis anticoagulated by citrate which may help to avoid negative calcium balance and reduce the incidence of complications. Abstract : Calcium supplementation is important for safety of regional citrate anticoagulation. In this study, we proposed a mathematical model including various types of filters based on the clearance of creatinine, phosphate and calcium for estimation of calcium supplementation during RCA‐IHD. We also validated our model in 12 sessions of intermittent hemodialysis. (A) Dialysis circuit for intermittent hemodialysis using regional citrate anticoagulation (RCA). (B) Comparison of the actual clearance of n‐Ca with the clearance of BUN and the hematocrit‐adjusted clearance of creatinine and phosphate given in the dialyzer leaflet. (C) Linear regression analysis of the actual clearance of n‐Ca. (D) The changes of ionized calcium levels during hemodialysis with guidance of the mathematical model during the treatment.