Can legal action be taken against a restaurant that does not call the ambulance for 4 hours knowing an employee slipped and fell (resulting in surgery due to a hemorrhage)?

Injuries to workers are governed by worker's compensation statutes and limit employees to worker's comp benefits.  Unless your employer did something intentional or almost intentional, it is unlikely that you would recover anything more than your medical and lost wage benefits.  However, I suggest that you consult with a couple worker's compensation lawyers in your area to discuss this.