Maryland emergency workers use these guidelines to determine whether a patient needs to be taken to a trauma center rather than a local hospital emergency room. If a trauma center is more than 30 minutes away by ambulance, the patient is transported by medevac helicopter. The fatal medevac trip this weekend was judged warranted based on the intrusion of an object into the car, not the injuries of the patients.

• Vital signs and level of consciousness: Check for signs of head injury, severely low blood pressure or low respiratory rate

• Anatomy of injury: Check for severe wounds such as penetrating injuries to the head, neck or torso; crush injuries; long-bone fractures; skull or pelvic fractures; and paralysis

• Mechanism of injury: Patients are transported if they have suffered falls of 20 feet for adults or 10 feet for children; if an object has intruded into a car by more than 12 inches near an occupant or 18 inches elsewhere; a motorcycle crash of greater than 20 miles per hour; and a crash involving an automobile and a pedestrian

• Other factors: Patients may be transported at the emergency worker's discretion based on criteria such as burns, age, pregnancy or the need for dialysis