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Geographic Modeling to Quantify the Impact of Primary and Comprehensive Stroke Center Destination Policies
Michael T Mullen1, William Pajerowski2, Steven R Messé2
1From the Department of Neurology (M.T.M., S.R.M., J.J.), Leonard Davis Institute of Health Economics (M.T.M., W.P., G.D.), Department of Healthcare Management, Wharton School (W.P., G.D.), Department of Emergency Medicine (C.C.M.), University of Pennsylvania, Philadelphia; Philadelphia Fire Department, PA (C.C.M.); Department of Emergency Medicine, Massachusetts General Hospital, Boston (M.A.); and Department of Emergency Medicine, Thomas Jefferson University, Philadelphia, PA (B.G.C., R.B.). michael.mullen@uphs.upenn.edu.
Background And Purpose:
We evaluated the impact of a primary stroke center (PSC) destination policy in a major metropolitan city and used geographic modeling to evaluate expected changes for a comprehensive stroke center policy.
Methods:
We identified suspected stroke emergency medical services encounters from 1/1/2004 to 12/31/2013 in Philadelphia, PA. Transport times were compared before and after initiation of a PSC destination policy on 10/3/2011. Geographic modeling estimated the impact of bypassing the closest hospital for the closest PSC and for the closest comprehensive stroke center.
Results:
There were 2 326 943 emergency medical services runs during the study period, of which 15 099 had a provider diagnosis of stroke. Bypassing the closest hospital for a PSC was common before the official policy and increased steadily over time. Geographic modeling suggested that bypassing the closest hospital in favor of the closest PSC adds a median of 3.1 minutes to transport time. Bypassing to the closest comprehensive stroke center would add a median of 8.3 minutes.
Conclusions:
Within a large metropolitan area, the time cost of routing patients preferentially to PSCs and comprehensive stroke centers is low.
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