Serum Potassium Trajectory during Acute Kidney Injury and Mortality Risk

Abstract

Background: The association between potassium (sK) level trajectory and mortality or the need for kidney replacement therapy (KRT) during acute kidney injury (AKI) has not been adequately explored. Methods: In this prospective cohort, AKI patients admitted to the Hospital Civil de Guadalajara were enrolled. Eight groups based on the sK (mEq/L) level trajectories during 10 days of hospitalization were created, (1) normokalemia (normoK), defined as sK between 3.5-5.5; (2) hyperkalemia to normoK; (3) hypokalemia to normoK; (4) fluctuating potassium; (5) persistent hypoK; (6) normoK to hypoK; (7) normoK to hyperK; (8) persistent hyperK. We assessed the association of sK trajectories with mortality and the need for KRT. Results: A total of 311 AKI patients were included. The mean age 52.6 years, and 58.6% were male. AKI stage 3 was present in 63.9%. KRT started in 36% patients, and 21.2% died. After adjusting for confounders, 10-day hospital mortality was significantly higher in group 7 and 8 (OR, 1.35 and 1.61, p = <0.05, for both, respectively), and KRT initiation was higher only in group 8 (OR 1.38, p = < 0.05) compared with group 1. Mortality in different subgroups of patients in group 8 did not change the primary results. Conclusion: In our prospective cohort, most patients with AKI had alterations in sK+. NormoK to hyperK and persistent hyperK were associated with death, while only persistent hyperK was correlated with the need for KRT.

Critically ill patients with COVID-19-associated acute kidney injury treated with kidney replacement therapy: Comparison between the first and second pandemic waves in São Paulo, Brazil

“…Differences between prescribed and offered KRT doses have been previously described, and it is well known that subdoses of KRT are associated with higher lethality [33][34][35]. Indeed, our study showed that the achievement of adequate markers of efficient KRT was associated with reduced lethality rates in both pandemic waves, especially with regard to serum potassium levels [36]. The decreased efficiency of KRT observed during the second wave might be attributed to several factors.…”