Know the 4 states of consciousness. If your practice sees patients that require electroencephalography (EEG), there are three main codes you’ll most likely be dealing with. The trick is knowing what makes each code tick — in other words, what are the main elements of these three EEG codes? Read on to learn what information to look for in the medical documentation when coding for EEG tests. Confirm State of Consciousness First When the surgeon documents an EEG procedure, you have three codes to choose from depending upon the patient’s state of consciousness during the procedure: Coding tip: Based upon the code descriptors above, you can list four states of consciousness: Knowing these four terms will lead you to the correct code for the EEG. Always read through the procedure note to confirm what the patient’s state of consciousness was when the surgeon performed the EEG. The physician obtains assessments in different conscious states for specific reasons. For example, the surgeon will obtain an EEG when the patient is awake and drowsy to confirm that the symptoms and signs persist when the activity of the patient’s brain is depressed. On the other hand, the physician may perform the EEG testing on the patient who is “asleep” to check if the patient has brain activity during a state of deep sleep or brain death. Observe EEG Duration Period When your physician performs an EEG, make sure he documents how long the recording lasted. The codes 95816-95822 apply to 20 to 40 minutes of recording time. “Once the duration of testing exceeds 40 minutes, the state of consciousness is no longer considered when choosing the appropriate CPT® code,” says Gregory Przybylski, MD, director of neurosurgery at the New Jersey Neuroscience Institute, JFK Medical Center in Edison. “Rather, the extended duration itself determines the appropriate code.” Extended EEG: When the physician records between 41 and 60 minutes of EEG time, you will choose from the extended EEG codes for 41-60 and more an hour, respectively. If the physician records between 41 and 60 minutes of EEG time, you will report 95812 (Electroencephalogram (EEG) extended monitoring; 41-60 minutes). On the other hand, when the EEG recording time exceeds 60 minutes, you should report 95813 (… greater than 1 hour) instead. Don’t miss: No matter whether the physician performed the recording in an awake/drowsy, awake/asleep, or asleep/coma state, you should always choose from codes 95812 and 95813 when the physician does an extended EEG. For example, the documentation indicates that the physician performed an awake/drowsy EEG that lasted 48 minutes. You would report 95812 for this service rather than 95816. Look for E/M Evidence You should always check to see if the physician performed a scheduled EEG or if he decided to perform an EEG for a patient who underwent an evaluation for a complaint in the same encounter. In the latter situation, you can report a separate evaluation and management (E/M) service. “In this circumstance, one would report the E/M service with modifier 25 (Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service) if the decision to perform the EEG on the same day is made during the E/M service,” Przybylski says. Coding example: The physician saw a patient he operated on six months ago for a brain cyst. The patient has come in today complaining of headaches. The physician performed a problem-focused history and an expanded problem-focused exam. The notes indicated low-complexity medical decision-making (MDM). Then, the physician conducted an awake/asleep EEG that lasted about 30 minutes. In this case, you can report both the EEG code as well as the E/M services. For the EEG, you will report 95819, and for the E/M service, you should report 99213 (Office or other outpatient visit for the evaluation and management of an established patient, which requires at least 2 of these 3 key components: an expanded problem focused history; an expanded problem focused examination; medical decision making of low complexity…) You should then append modifier 25 to 99213 to show that the E/M service was separately identifiable from the EEG service. And don’t forget to report ICD-10 code R51 (Headache) as the diagnosis for the headache.