The first time the teenagers are coming down the emergency stairs in the hospital, the brace on Matt's leg changes from his left to his right leg, and then subsequently changes back to his left leg again.
While on the run in the hospital, the cobwebs on Joey's face appear and disappear between scenes.
The hospital has candy stripers doing duties that only RNs, LPNs or Doctors can perform. Candy stripers, in real life hospitals, do not practice medicine.