P1089REGIONAL CITRATE ANTICOAGULATION VERSUS LOW MOLECULAR WEIGHT HEPARIN ANTICOAGULATION FOR CONTINUS VENOVENOUS HEMOFILTRATION IN PATIENTS WITH SEVERE HYPERCALCEMIA: A RETROSPECTIVE CASE-CONTROL STUDY

Abstract Background and Aims Severe hypercalcemia, poor conservative treatment effect, or combined with renal dysfunction, heart failure, intermittent hemodialysis treatment is recommended. But calcium-free hemodialysis could cause rebound of serum calcium, hypovolemia and hypotension. Continuous renal replacement therapy (CRRT) is the most commonly used treatment in critically ill patients with severe AKI. Some case reports showed that CRRT successed control calcium with stable hemodynamics, no rebound hypercalcemia, but there was only one case used continuous venovenous hemofiltration (CVVH). During CVVH treatment, clotting in the extracorporeal circuit shortens the filter and catheter lifespan, causes blood loss, and decreases solute clearance, consequently, reduces the effectiveness of CVVH and increases the treatment cost and medical stuff’s workload. So how to safely decrease calcium level and how to choose appropriate anticoagulants during CVVH in esvere hypercalcemia patients is a challenging work. We conducted a retrospective study to evaluate the efficacy and safety of regional citrate anticoagulation (RCA) versus low molecular weight heparin (LMWH) anticoagulation for CVVH in severe hypercalcemia patients. Method Between January 2014 and May 2019, severe hypercalcemia patients requiring CVVH were screened and divided into the RCA and LMWH-anticoagulation group according to the CVVH anticoagulation strategy they accepted. Serum calcium reduction rate (RRSeCa), filter lifespan, bleeding, totCa/ionCa ratio, citrate accumulation, and catheter occlusion were evaluated as outcomes. Results Of the 33 included patients, RCA and LMWH-anticoagulation were employed for CVVH in 14 and 43 filters, respectively. The serum calcium reduction rate (RRSeCa) was not significantly different between the LMWH-anticoagulation and RCA group (P = 0.320). Compared to LMWH-anticoagulation, RCA significantly prolonged the filter lifespan (> 72 hours vs. 24.0 hours [IQR, 15.0-26.0], P = 0.012). The incidence of filter failure was 55.8% (24/43) in the LMWH -anticoagulation group and 21.4% (3/14) in the RCA group (P = 0.033), respectively. The adjusted results demonstrated that RCA could significantly reduce the risk of filter failure (P = 0.028, 95% CI 0.076-0.859, HR = 0.255). No citrate accumulation was observed in RCA-CVVH patients. Conclusion In patients with severe hypercalcemia who underwent CVVH, both RCA CVVH and LMWH-anticoagulation CVVH could effectively decrease calcium levels. RCA CVVH had better filter lifespan and no obvious adverse events, compared with the LMWH-anticoagulation CVVH. Further prospective, randomized, control studies are warranted to obtain robust evidences.