A few minutes on the U.S. CDC web site yielded the following round numbers for annual mortality in the United States from 2013, the most recent available data, in categories selected by me. (Some deaths will be in multiple categories.) This is out of about 2,500,000 deaths total.
Complications of surgical or medical care: 2,800
Motor Vehicles: 43,500
Off hand, speaking as a dilettante economist, I’d say if we want to make a real difference in saving lives, we should start by outlawing cigarettes. Then alcohol.