Basic Procedure Coding Systems – Week 3 Lecture 1

Overview of Anesthesia

We have covered a lot of material in a short period of time! During Week 1 we reviewed CPT coding and when this code set would be used for patient encounters. Last week, we focused on HCPCS coding and the proper use of this code set. This week we will review another section of the CPT manual. Anesthesia is the smallest section of CPT but there is a lot of important guidelines and instructional notes surrounding these codes that are important for medical coders to review when applying codes to patient documentation accurately from this section.

Additionally, Anesthesia codes use a special formula that calculates what would be billed to a third-party payer for reimbursement purposes. This formula for an anesthesia payment would be B (base units) + T (time units) + Modifying units (if allowed) x conversion factor which would equal the total amount of a claim submitted to an insurance company. Your chapter readings, videos, live lecture, and assignments will provide examples and break this formula down further.

Another key difference with Anesthesia codes are qualifying circumstances and physical status modifiers. Qualifying circumstance CPT codes are add-on codes (designated by the + sign symbol), that are reported in addition to the anesthesia procedure code. Examples may be for patient of an extreme age, such as younger than 1 year old or older than 70 years old (+99100). Another example may be Anesthesia that is complicated by an emergency condition (+99140). It is essential for you to have a firm understanding of these unique rules when coding for anesthesia otherwise, accuracy will not be achieved, and your claim will either be denied or not reimbursed correctly. Below is an example of qualifying circumstance add-on codes and descriptions.

Physical status modifiers are used in conjunction with an anesthesia code which helps to identify the patient’s health at the time of a procedure. There are a total of six physical status

modifiers as outlined below with their descriptions:

Putting it all together:

Let’s now see how this would look if we are breaking down all components:

A 77-year old female patient (qualifying circumstance for extreme age, value 1), with uncontrolled Type II diabetes (value of 1) has a 3-cm lesion removed from her left knee (base value of 3). The total anesthesia time was 60 minutes, and the third-party payer prefers time in units of 15 minutes (4 units total). During the procedure the Anesthesiologist recorded that the patient’s physical status was a P3 for severe systemic disease (relative value of 1), for the uncontrolled Type II diabetes.

Ø 3 base procedure value

Ø 4-time units

Ø 2 modifiers: physical status = 1; and extreme age = 1

Ø 9 total units

The codes selected that would identify these elements for this patient encounter would be:

Ø 00400-P3 (Anesthesia for procedures on the integumentary system on the extremities with severe system disease (uncontrolled diabetes Type II))

Ø +99100 (Anesthesia for a 77-year-old patient

Ø 9 Units will be billed to the third party

The conversion factor is the dollar value for each unit that varies based on geographic location due to the cost of practicing medicine which can differ throughout the country. As you can see from the below example, the conversion factor is valued differently depending on which state and region the Anesthesiologist is practicing. This would be the final step of the formula that is added to a CMS-1500 claim form.

Next week we will begin reviewing the Surgery section, which is the largest section of the CPT manual as codes are included for each body system in this section. Your understanding of proper use of anesthesia coding will increase your knowledge of coding when we move to the Surgery section.