Impact of Treatment Modalities on Intensive Care Unit Length of Stay for Patients Admitted With Severe Hyponatremia

The diversity in presentation and cause of hyponatremia leads to a wide array of treatment modalities which are selected based on severity, chronicity, volume status, and putative cause. Due to the variability in treatment selection, it is pertinent to identify the clinical impact of the various treatment modalities and rescue therapies to inform future care.

To evaluate the association between treatment modality and length of stay for patients with severe hyponatremiaMethods:This single-center, retrospective study included patients 18 years of age or older with glucose-corrected serum sodium levels of <125 mEq/L upon admission to the intensive care unit (ICU). The primary endpoint was ICU length of stay, and its association with treatment modality was assessed using multivariable Poisson regression with the following explanatory variables: 3% sodium chloride, 1.8% sodium chloride or isotonic fluids, diuretics, proactive therapy, rescue therapy, nephrology consultation, baseline volume status, and pretreatment sodium level.

Eighty-two patients were included with a median age of 65 years old (Q1, Q3: 57, 72). The median glucose-corrected serum sodium was 116.3 mEq/L (Q1, Q3: 112.9, 120.5) and the median ICU length of stay was 3 days (Q1, Q3: 2, 4). Multivariable analysis, adjusting for baseline serum sodium levels, revealed the use of proactive and early reactive therapy (incidence rate ratio [IRR] 1.38, 95% confidence interval [CI] 1.11-1.71) and nephrology consultation (IRR 1.22, 95% CI 1.01-1.46) were associated with increased length of ICU stay.

Nephrology consultation and the use of proactive therapies were associated with increased ICU length of stay. Accurate identification of patients at high risk for osmotic demyelination syndrome that may benefit from proactive therapies is imperative, as use of proactive therapies in low-risk patients may prolong length of stay.