Saline Versus Balanced Crystalloids for Adults With Aneurysmal Subarachnoid Hemorrhage: A Subgroup Analysis of the SMART Trial

Abstract

Background Whether the composition of intravenous crystalloid solutions affects outcomes in adults with aneurysmal subarachnoid hemorrhage (aSAH) remains unknown. Therefore, we determined whether the use of saline is associated with a lower risk of disability and death in patients with aSAH compared with balanced crystalloids. Methods We conducted a post hoc subgroup analysis of SMART (Isotonic Solutions and Major Adverse Renal Events Trial), a pragmatic, unblinded, cluster‐randomized, multiple‐crossover clinical trial that enrolled 15 802 adults between June 2015 and April 2017. We compared IV administration of saline to balanced crystalloids in consecutively enrolled patients with aSAH aged 18 years or older whose ruptured aneurysm was procedurally secured at a single academic center in the United States. The primary outcome was the score on the modified Rankin scale (range, 0 [no symptoms]–6 [death]) at 90 days obtained from a prospective institutional stroke registry. Secondary outcome included death by 90 days. Logistic or proportional odds regression models were used to test for between‐group differences adjusted for age, hypertension, aSAH grade, and procedure type. Results Of the 79 patients with aSAH procedurally treated during the Isotonic Solutions and Major Adverse Renal Events Trial study period, 78 were enrolled (median age, 58 years; interquartile range, 49–64.5; 64% female), with 41 (53%) assigned to saline and 37 (47%) to balanced crystalloids. Plasma‐Lyte was the primary balanced crystalloid used. Among 72 patients with 90‐day modified Rankin scale assessment, the adjusted common odds ratio, for the modified Rankin scale was 0.68 (95% CI, 0.28–1.63; P=0.39), with values <1.0 favoring saline. By 90 days, 2/39 patients (5%) in the saline group and 9/35 (26%) in the balanced‐crystalloids group had died (adjusted common odds ratio, 0.06; 95% CI, 0.00–0.50; P=0.02). Conclusions Among procedurally treated patients with aSAH, the risk of disability or death at 90 days did not significantly differ between saline and balanced crystalloids. Death occurred less frequently with saline than balanced crystalloids.

Keywords

• clinical trial
• critical care
• intravenous fluids
• subarachnoid hemorrhage