Hypernatremia in Critically Ill COVID-19 Patients: Is it a manifestation of COVID-19 or acquired in the ICU?

Abstract

Objective: It has been noted that COVID-19 patients experienced electrolyte problems more frequently, and these disturbances were linked to unfavorable results. The purpose of this study was to investigate the incidence and consequences of hypernatremia in severely ill COVID-19 patients receiving intensive care (ICU). Methods: Retrospective data analysis was done on COVID-19 patients who were admitted to ICUs over a six-month period at two centers. Results: Data from 270 patients were collected in total. 138 (51%) patients developed hypernatremia (Na >145 mmol/l) during ICU stay. Hypernatremia was observed to be more in older or ventilated patients, whereas less in patients with chronic kidney disease. However, in patients with and without hypernatremia, unfavorable outcomes like length of stay (LOS) or mortality were comparable. Frequency of hypertension, septic shock as well as SOFA score, and serum BUN levels were significantly higher in moderate to severe hypernatremic (Na ≥150 mmol/l) vs mild hypernatremic (Na=146-149 mmol/l) group. Moderate to severe hypernatremia had worse prognosis than the mild group: ICU LOS (12 vs 9-day, p=0.033), ICU mortality (86% vs 61%, p=0.001 and 28-day mortality (89% vs 68%, p=0.004). Elevated serum BUN levels and moderate to severe hypernatremia were independent predictors of both ICU and 28-day mortality. Conclusion: Critically ill COVID-19 patients experienced hypernatremia more frequently than expected, suggesting that hypernatremia may be a manifestation of systemic involvement of COVID-19 rather than iatrogenic. Patients with and without hypernatremia were found to have similar outcomes.