Iatrogenic hypoglycaemia following glucose-insulin infusions for the treatment of hyperkalaemia

To study the incidence of, and risk factors for, iatrogenic hypoglycaemia following GwI infusion in our institution.

Hyperkalaemia is a life-threatening biochemical abnormality. Glucose-with-insulin (GwI) infusions form standard management, but risk iatrogenic hypoglycaemia (glucose ≤ 3.9 mmol/L). Recently updated UK guidelines include an additional glucose infusion in patients with pretreatment capillary blood glucose (CBG) < 7.0 mmol/L.

Retrospective analysis of outcomes for GwI infusions prescribed for hyperkalaemia from 1 January to 28 February 2019, extracted from the Newcastle upon Tyne Hospitals NHS Foundation Trust electronic platform (eRecord).

132 patients received 228 GwI infusions for hyperkalaemia.

Incidence, severity and time to onset of hypoglycaemia.

Hypoglycaemia incidence was 11.8%. At least 1 hypoglycaemic episode occurred in 18.2% of patients with 6.8% having at least 1 episode of severe hypoglycaemia (< 3.0 mmol/L). Most episodes (77.8%) occurred within 3 h of treatment. Lower pretreatment CBG (5.9 mmol/L [4.1 mmol/L-11.2 mmol/L], versus 7.6 mmol/L [3.7 mmol/L-31.3 mmol/L], P = .000) was associated with hypoglycaemia risk. A diagnosis of type 2 diabetes and treatment for hyperkalaemia within the previous 24 h were negatively associated.

Within our inpatient population, around 1 in 8 GwI infusions delivered as treatment for hyperkalaemia resulted in iatrogenic hypoglycaemia. Higher pretreatment CBG and a diagnosis of type 2 diabetes were protective, irrespective of renal function. Our findings support the immediate change to current management, either with additional glucose infusions or by using glucose-only infusions in patients without diabetes. These approaches should be compared via a prospective randomized study.