Regional citrate anticoagulation with calcium replacement in pediatric apheresis

The objective of this retrospective analysis was to present our single-center experience with intravenous (IV) calcium replacement and regional citrate anticoagulation in pediatric apheresis therapy with the aim of developing a standard operating procedure to minimize symptomatic hypocalcemia.

We analyzed apheresis procedures in patients <18 years of age over a 2-year time period (Jan 2012 to Dec 2014). Procedures in tandem with other extracorporeal therapies, including continuous renal replacement therapy, extracorporeal liver support, and extracorporeal membrane oxygenation, were excluded.

Two-hundred and six patients underwent 1176 procedures. All procedures were performed with acid citrate dextrose formula A (ACD-A) for anticoagulation and IV calcium replacement. The majority of procedures (56.7%) were therapeutic plasma exchange (TPE). The average rate of IV calcium chloride (2.16 mg/mL of elemental calcium) was 60.4 ± 21.4 mL/h while inlet flow rate was 43.7 ± 16.3 mL/min. Patients experienced hypocalcemia in 63 of 1176 procedures (5.3%), including 48 episodes (4.1%) of hypocalcemia during apheresis treatment. Two procedures with hypocalcemia had symptoms: one slight lip twitch and one patient with abdominal pain. No hemodynamic alterations were noted in any procedure associated with hypocalcemia. Hypocalcemia was seen the least with RCE. For patients with hypocalcemia prior to the apheresis session, we used a calcium infusion running at 1.6 times the inlet flow rate.

Running IV calcium at 1.4 times the inlet flow rate resulted in a lower incidence of hypocalcemia than reported in literature describing other approaches to apheresis. It nearly eliminated episodes of symptomatic hypocalcemia.