Abstract 2672: Osmotic Therapy in the Management of Cerebral Edema after Stroke across the United States.

Abstract

Introduction Osmotically active substances like mannitol and hypertonic saline are widely accepted options in management of cerebral edema after ischemic stroke. However, use of these agents can be very heterogeneous in practice given the lack of randomized clinical trials to confirm and compare their effectiveness. We queried the PREMIER database to investigate the differences in the use of osmotic therapy in ischemic stroke patients across the United States. Methods First ever ischemic stroke-related hospitalizations (ICD-9 codes 433.x1, 434.x1 and 436) of patients aged 18+ years were reviewed for fiscal years of 2007-2010 from the Premier Perspective™ Database. Use of osmotic therapy and time of its administration were determined through pharmacy billing records for mannitol and hypertonic saline while presence of documented cerebral edema was identified using ICD-9 diagnosis code 348.5.Differences in osmotic treatment were tested by gender and race of the patient as well as hospital characteristics. Results We identified 244,482 patients with first ever ischemic stroke. Of these, 12,301 (5%) were treated with osmotic therapy, the majority of which occurred within 7 days of hospitalization. Of those receiving osmotic therapy, 64% received mannitol, 44% received hypertonic saline and 7% received both treatments. The ICD -9 code for cerebral edema was associated to 11% of these cases. Essentially no differences in race (63% whites) and sex distribution (49% females) were found. The majority of osmotic therapy use occurred in urban areas (93%). There was no difference in use between teaching vs non-teaching institutions (51% vs 49%). Conclusions Despite the lack of evidence to support its effectiveness, we found that osmotic therapy was given to 5% of stroke patients during fiscal years 2007-2010, primarily in urban centers. Only a minority of treated cases were associated with the ICD-9 code for cerebral edema, which is the principal indication for this treatment, likely reflecting a diffuse underutilization of this diagnostic code in practice. Mannitol was more frequently used than hypertonic saline in both teaching and non-teaching hospitals. Randomized control trials are warranted to demonstrate the efficacy of osmotic therapy using mannitol or hypertonic saline in ischemic stroke.