Endocrine Abstracts

A frail, long-term surgical inpatient, was under-nourished on TPN. He had a tendency towards hypocalcaemia and was under regular review by the surgical and nutrition team. It was noted on his routine monitoring that his Ca had fallen to 1.78 mmol/l (2.2-2.6 mmol/l). He was reviewed out-of-hours and prescribed 10mls of 10% Calcium Gluconate infused over 10 minutes, as per the hospital guidance for the treatment of hypocalcaemia. A further prescription of calcium gluconate 10% in 100mls (10x10 ampoules) in 1l of normal saline was written up following the initial infusion. Unfortunately the patient deteriorated and after further assessment, it was noted that his venous blood gas calcium was immeasurably high. A confirmatory plasma calcium was noted to be 6.4 mmol/l (and rechecked to confirm that the original sample had not be accessed from the PICC line, where the calcium infusion had been administered). An urgent endocrine opinion was sought which delineated the options of fluid hydration, haemofiltration or potential bisphosphonate infusion. An intensive care review was facilitated and the decision to continue with ’ward-based’ care was made. Fluid infusion to facilitate calcium excretion was commenced and within 24 hours, the calcium had improved to 4.78 mmol/l. Ongoing fluid management was continued but sadly the patient deteriorated and died, with sepsis contributing to his demise. On review of his care, it was noted that Calcium Chloride (and not Calcium Gluconate) had been administered (despite dual nursing verification). This has ~3 times the calcium content. [Calcium chloride 10 mmol/10ml injection = 6.8 mmol/10ml whilst Calcium gluconate 10% injection = 2.2 mmol/10ml]. As a result of this incident, calcium chloride 10 mmol/10ml injection ampoules have been removed from all ward stock lists except critical care units, cardiac specialty wards and emergency departments and guidelines which currently recommend use of calcium chloride 10 mmol/10ml injection have been updated e.g. management of hyperkalaemia.