Background and Importance Potassium metabolism disorders are the most frequent electrolyte alteration in clinical practice. Early detection of hypokalaemia could prevent future complications.

Aim and Objectives To know the prevalence of hypokalaemia disorders in adults admitted in a third-level hospital. Evaluate the aetiology and the corrective treatment during the following 24 hours. To identify improvement actions.

Material and Methods Descriptive observational study of three cross-sections carried out during December 2022. In each section, all the analytical determinations that included potassium determination were selected, and the medical records of patients with hypokalaemia (K <3.5 mEq/L) were reviewed.

The severity of the alteration and the corrective treatment were determined within 24 hours after the analytical determination.

Hypokalaemia was classified according to severity as: mild (3–3.49 mEq/L), moderate (2.51–2.99 mEq/L) or severe (≤2.5 mEq/L). Possible causes were considered: hypomagnesemia, pharmacological, idiopathic or insufficient intake (nothing by mouth without potassium supplement).

Results In each section, were identified 116, 116 and 112 (344 in total) patients with potassium determination. The patients admitted each day were 327, 323 and 321, respectively. 45/344 (13%; 95% CI [9.5–16.6]) had hypokalaemia (40 mild, 4 moderate and 1 severe).

21/45 patients had a pharmacological cause (46.7%; 95% CI [32.1–61.2]), furosemide being prescribed in 15 of them. 11/45 patients presented hypomagnesemia as a probable aetiology (24.4%; 95% CI [11.9–37]). It was identified as a possible idiopathic cause in 9/45 patients (20%; 95%CI [8.3–31]) and in 4/45 (8.9%; 95%CI [6–17.2]) insufficient supply of potassium was observed (patients on an absolute diet without supplementation).

18/45 patients did not receive corrective treatment (40%; 95% CI [25.7–54.3]).

Conclusion and Relevance Hypokalaemia occurs in 13% of daily laboratory analysis in the hospital, the main cause being pharmacological. In the first 24 hours, 40% of patients do not receive corrective treatment.

The establishment of a systematised computerised extraction of patients with alterations in potassium levels would detect unidentified alterations. It could be possible to establish corrective treatment earlier, and this fact could be able to benefit more than 5,000 patients annually in our setting.

Conflict of Interest No conflict of interest.