[Influence of post-filter ionic calcium gradients on the longevity of CRRT local citrate anticoagulation in extracorporeal circulation].

Objective

To investigate the influence of different post-filter ionic calcium (Ca2+) gradients (0.25-0.35 mmol/L vs>0.35-0.50 mmol/L) on the extracorporeal lifetime of local citrate anticoagulation (RCA) for continuous renal replacement therapy (CRRT).

Methods

Patients who underwent CRRT with RCA at West China Hospital of Sichuan University from March 2021 to June 2022 were retrospectively selected. The basic information and the values of post-filter Ca2+at 0, 2, and 6 hours after the start of treatment and every 6 hours thereafter were collected. The patients were divided into low concentration group (0.25-0.35 mmol/L mmol/L) and high concentration group (>0.35-0.50 mmol/L) according to the mean value of Ca2+concentration per treatment, and propensity score matching was performed in a 1∶1 ratio to evaluate the effect of post-filter [iCa2+] on the duration of extracorporeal circulation in different groups.

Results

A total of 232 patients (147 males and 85 females) aged (58.2±16.9) years were enrolled. There were 431 cases treated with CRRT for 12 592 h, including 317 cases (73.5%) in the low concentration group and 114 cases (26.5%) in the high concentration group. The baseline data of the two groups were matched and analyzed. Coagulation events occurred in 54.9% (62/113) and 54.0% (61/113) in the low and high concentration groups, respectively (P=0.894). The median survival on extracorporeal circulation was 65.0 (29.0, 72.0) h and 68.0 (31.5, 72.0) h in the two groups, respectively (P=0.805). Multivariate Cox regression analyses showed that post-filter [iCa2+] had no effect on extracorporeal life expectancy (HR=0.99, 95%CI:0.55-1.79).

Conclusion

During CRRT treatment with RCA, the desired anticoagulant effect can still be achieved when the post-filter [iCa2+] target was set to 0.25-0.50 mmol/L.