Balanced multi-electrolyte solution versus normal saline for fluid therapy in aneurysmal subarachnoid hemorrhage: an influence on fluid and electrolytes balance and outcome.

Introduction: Isotonic crystalloids are commonly used for maintaining fluid balance and cerebral perfusion pressure in critical care patients with aneurysmal subarachnoid hemorrhage (aSAH). However, the relatively high concentration of chloride in normal saline (NS) might lead to hyperchloremia or acute kidney injury, comparing with multi-electrolyte solutions (BMES). The aim of the study is to compare the incidence of hyperchloremia in aSAH patients and provide feasibility and safety research for further study. Methods: This is a pilot study of a single center, randomized, controlled trail. Patients were enrolled randomly to receive BMES or NS for 3 days of ICU stay. Results: Overall, 87 patients were randomized to receive BMES or NS, 60 patients (30 in each group) were enrolled for final analysis. Within 3 days of randomization, hyperchloremia occurred in 18/30 (60%) patients in the BMES group and 23/30 (76.7%) in the NS group (p = 0.165, relative risk 0.58, 95% CI 0.27-1.28). Incidence of hyperchloremia (BMES 36.7% vs. NS 63.3%, p = 0.039) and hyperchloremic acidosis (BMES 36.7% vs. NS 63.3%, p = 0.039) were decreased on trial day 1. There were no differences on bicarbonate, anion gap, serum creatinine, incidence of acute kidney injury, or length of hospital stay between groups. Discussion: For patients with aSAH, the use of BMES did not result in a lower risk of hyperchloremia, and also did not increase the incidence of hyponatremia or intracranial hypertension over NS, which warrants further research.