Use of intravenous calcium in emergencies to treat patients with hyperkalemia and digoxin poisoning and its impact on short-term outcome

Objectives

Patients with digitalis intoxication (DI) and hyperkalaemia are frequently encountered in the emergency department (ED). This alteration may require intravenous (iv) calcium, but its administration has been considered to increase cardiotoxicity and mortality in patients with DI. We studied the effect of iv calcium on mortality and 30-day readmission in patients with hyperkalaemia and DI.

Methods

A retrospective, multicentre, retrospective cohort study including all patients with DI and hyperkalaemia from 2004 to 2023 seen in 6 hospital emergency departments. Two cohorts were created according to iv calcium administration, and demographic, clinical, electrocardiographic and outcome variables (mortality, readmission and combined event at 30 days) were collected.

Results

117 patients with ID and hyperkalaemia were collected and 29% were administered iv calcium. Seventy-eight point six percent were women, with a median age of 82.8 years. Cardiological symptoms were present in 57.3%, 47% digestive and 37.6% neurological. Cardiac arrhythmia was present in 86.3%, the most frequent type being slow supraventricular arrhythmia in 76.1%. The presence of cardiological symptoms (76.5% vs 49.4, p = 0.007), arrhythmias (97.1% vs 81.9%, p = 0.037), and higher levels of creatinine (70.6% vs 42.2%, p = 0.005) and serum potassium (94.1% vs 31.3%, p < 0.001) was more frequent in the group receiving iv calcium. An association was found between the administration of IV calcium. An association was found between calcium administration and the combined event at 30 days (ORa 3.11, 95% CI:1.02–9.53), but this increase was at the expense of more readmissions (ORa 3.58, 95% CI, 1.04–12,33), with no relationship found with mortality at 30 days (ORa 0,75, 95% CI: 0.18–3.09).

Conclusion

Calcium administration in hyperkalaemia and ID is not associated with short-term mortality.