Investigators say a man driving a new Dodge Challenger crashed through a fence on the hospital grounds around 2:30am.
The car was going so fast it didn't stop until it ran into a guard rail along the helipad. The car stopped only 50 feet from the air ambulance parked there.
Two men were taken to a hospital to be treated. A police spokesperson says the driver is in serious condition, but the passenger suffered only minor scrapes and bruises.
Police say they believe alcohol may have played a role in this accident.
"We do believe at this time that alcohol was involved," said HPD Sgt. Ignacio Izaguirre. "There was an alcoholic beverage inside."
Investigators are waiting for blood alcohol test results. No charges have yet been filed.
The damage to the hospital grounds is estimated to be in the thousands or tens of thousands of dollars.