Prophylactic low dose continuous calcium infusion during peripheral blood stem cell (PBSC) collections to reduce citrate related toxicity

Abstract

Background: Citrate toxicity is one of the most frequent complications of apheresis procedures. It is caused by the infusion of the acid citrate dextrose (ACD), which chelates the calcium ions.

Aims: The aim of this study is to assess the effectiveness of prophylactic continuous infusion of calcium gluconate over intermittent bolus infusion to reduce citrate toxicity during large volume peripheral blood stem cell collection.

Materials and methods: We retrospectively analysed the records of PBSC collection procedures performed from March 2010 to December 2013. Donors were selected as per the set guidelines. Machine used to perform the procedures was Cobe spectra. The study population was divided into 2 groups. One composed of intermittent intravenous bolus infusion at the onset of hypocalcaemic symptoms, the other composed of calcium gluconate administration as continuous infusion throughout the procedure.

Result: The most common reported hypocalcaemic symptoms were mild perioral paresthesia followed by digital numbness. Of the 50 individuals who were injected with bolus calcium 40 (80%) individuals suffered from symptoms of hypocalcaemia, whereas 23 of 66 individuals (34.8%) suffered from hypocalcaemia in the continuous infusion group. This difference was significant (P < 0.001). Both groups were compared with respect to age, gender ratio, weight of the individuals, total blood volume processed, ACD used, calcium gluconate dose used, time taken for the procedure, the product volume. Significant difference was noticed only with respect to the product volume. This implies that the groups were comparable with respect to parameters such as age, gender ratio, weight of the individuals, total blood volume processed, ACD used, calcium gluconate dose used, and the time taken for the procedure. Also that significantly more products (244 v/s 204 ml) was collected in the continuous infusion group.

Conclusions: Our results show that prophylactic continuous IV administration of low dose calcium-gluconate throughout the PBSC harvesting procedure reduced the incidence as well as the severity of citrate related toxicity. This increases his/her tolerance to withstand longer durations of the procedure and collect more volume of the product, hence may reduce the number of sittings of the procedure.

Keywords: ACD; Apheresis; Bolus; Calcium; Continuous infusion.