Like many of the Chicago area's 20 safety-net hospitals, which act as a stop-gap medical system for the poor, St. Anthony is facing unprecedented pressure to adjust its business model amid the most sweeping changes to the health care system in decades. While their larger and better-financed counterparts are investing millions in new facilities, equipment and physicians, many of Chicago's safety nets live day-to-day, week-to-week, much like their patients.Closure of such hospitals, often the largest employers in their neighborhoods, would have major implications on local economies but also could create health care deserts where major swaths of the city would be left without immediate access to health care.