The furious pace of oil exploration that has made North Dakota one of the healthiest economies in the country has had the opposite effect on the region’s health care providers. Swamped by uninsured laborers flocking to dangerous jobs, medical facilities in the area are sinking under skyrocketing debt, a flood of gruesome injuries and bloated business costs from the inflated economy.

The problems have been acute at McKenzie County Hospital here. Largely because of unpaid bills, the hospital’s debt has climbed more than 2,000 percent over the past four years to $1.2 million, according to Daniel Kelly, the hospital’s chief executive. Just three years ago, Mr. Kelly added, the hospital averaged 100 emergency room visits per month; last year, that average shot up to 400.