Prevalence and Prognostic Impact of Dehydration Assessed by Caval Index in Acute Ischemic Stroke: A Prospective Observational Study.

BACKGROUND

Dehydration is a common but underrecognized in acute ischemic stroke and is associated with increased complications and poor outcomes.

OBJECTIVES

This study aimed to determine the prevalence of dehydration among stroke patients presenting to the emergency department (ED) and evaluate its prognostic impact on clinical outcomes using the inferior vena cava (IVC) collapsibility index.

METHODS

In this prospective observational study, consecutive adult patients with acute ischemic stroke admitted to the ED were evaluated. Volume status was assessed at presentation by bedside ultrasound measuring the IVC collapsibility index (CI), alongside laboratory markers including blood urea nitrogen/creatinine ratio and estimated glomerular filtration rate. Dehydration was defined as CI > 50% with an IVC expiratory diameter < 2.1 cm. Neurological severity was assessed using the National Institutes of Health Stroke Scale (NIHSS), and functional outcomes were determined by the modified Rankin Scale (mRS) at discharge and 3 months. Patients were categorized by treatment modality as conservative, intravenous thrombolysis, or mechanical thrombectomy, with poor outcome defined as mRS 3-6.

RESULTS

Among 211 patients, hypovolemia was present in 72 (34.1%). Multivariable logistic regression identified collapsed IVC as an independent predictor of poor functional outcome in the anterior circulation cohort (adjusted OR: 2.606, 95% CI: 1.097-6.189, p = 0.030), even after adjusting for critical confounders such as baseline NIHSS. Conversely, no significant association between volume status and prognosis was observed in posterior circulation strokes.

CONCLUSION

Dehydration assessed by IVC collapsibility is independently associated with poor outcomes, particularly in anterior circulation strokes. Early ultrasonographic volume assessment may assist in optimizing treatment strategies in the ED.