Anesthesia Coding Alert

Question: Our CRNA was asked to provide anesthesia during a patient’s colonoscopy. How do we bill the anesthesia? I’m not sure about the base code and subsequent time increment codes. Could you also share an example of coding for a diagnostic colonoscopy, screening colonoscopy, and EGD? Do we append modifiers since the gastroenterologist is directing/supervising the CRNA?

Massachusetts Subscriber

Answer: The correct anesthesia base code will depend on the documentation of exactly what took place. Your options are as follows:

• For a screening colonoscopy, report 00812 (Anesthesia for lower intestinal endoscopic procedures, endoscope introduced distal to duodenum; screening colonoscopy), which has a base unit value of 4 in the RVG^® although Medicare only allows 3 units.
• For diagnostic colonoscopy, submit 00811 (Anesthesia for lower intestinal endoscopic procedures, endoscope introduced distal to duodenum; not otherwise specified) with a base unit value of 4.
• For EGD (esophagogastroduodenoscopy), report 00731 (Anesthesia for upper gastrointestinal endoscopic procedures, endoscope introduced proximal to duodenum; not otherwise specified) with a base unit value of 5.

When a screening colonoscopy becomes a diagnostic procedure, CMS directs you to report 00811 with the PT modifier (Colorectal cancer screening test; converted to diagnostic test or other procedure). It is not unusual for this situation to occur, so pay attention to your provider’s notes so you won’t miss the add-on modifier.

Based on the information you provide, you’ll need to append modifier QX (Qualified nonphysician anesthetist without medical direction by a physician) to the appropriate anesthesia code to indicate that the CRNA performed the anesthesia service under supervision of the gastroenterologist. If the CRNA is medically directed by an anesthesiologist, the modifier will change to QY (Medical direction of one certified registered nurse anesthetist (CRNA) by an anesthesiologist) for the CRNA service.

Tip: The surgeon is not allowed to bill or report an anesthesia claim for medical direction or supervision of a CRNA.

Time reporting: The proper way to report anesthesia time is to record it in minutes. Many payers follow one unit of time for each 15-minute increment of anesthesia time. For example, a 45-minute procedure, from start to finish, would represent three units of anesthesia time.

Example: Let’s say the anesthesia code is 00731 (for EGD), the anesthesia start time is 11:01, and the anesthesia end time is 11:21. This translates to 20 anesthesia minutes, or 1.3 to 2 time units, depending on whether the insurance recognized exact time (like Medicare) or rounds time up to the nearest whole number. To calculate the charge, you would add the time units (2) to the procedure base units (5) for a total unit value of 7 units. Multiply 7 by the correct anesthesia conversion factor for your practice to reach the final value of the charge.