Several of the performance improvement (PI) audit filters typically used at trauma centers include a time parameter. These include:

• Craniotomy > 4 hrs
• Laparotomy > 4 hrs
• OR for open fracture > 8 hrs
• Compartment syndrome > 2 hrs

The question that needs to be asked is: 2 or 4 or 8 hours after what?

There are several possible points at which to start the clock:

• Arrival in the ED
• When the diagnosis is made
• When the decision to operate occurs

The answer is certainly open to interpretation. Here is my opinion on it:

The purpose of a PI filter is to measure system performance. There are a myriad of system problems that can delay taking a patient to the OR. These include care delays in the ED, delays in getting or interpreting diagnostic tests, delays in contact or response for consultants, delays in diagnosis, delays in OR scheduling or availability, and more. Does it make sense to limit the evaluation of your system by setting one of the later decision points as your start time?

Bottom line: I recommend starting the audit filter clock at the time of patient arrival in the ED. This enables the PI program to evaluate every system that can possibly enable or impede your patient’s progress to the OR.