Coding for Anesthesia and Surgeries

Procedure Performed: Examination of the right knee under general anesthesia. Diagnostic arthroscopy with subtotal medial meniscectomy and chondroplasty of the medial femoral condyle.

Under satisfactory endotracheal general anesthesia, the patient was placed supine on the operating table. The right leg was placed in a well-padded, thigh-holding device flexing the hip 20 degrees. A pneumatic tourniquet was applied at 300 mm Hg but not inflated. A routine 10-minute Betadine scrub followed by prep and sterile draping of the extremity was carried out.

Through a transpatellar tendon approach, after infiltration of the skin and subcutaneous tissue with 0.25% Marcaine and Epinephrine, a patellar tendon splitting incision was made. A 25-degree Wolf arthroscope was introduced into the suprapatellar pouch, after successive insertion of a blunt cannula and trocar. A medial irrigation portal was established with satisfactory flow. An accessory anteromedial portal was then made.

The right knee was examined and appeared to be stable. The patella had some Grade II changes in the medial femoral condyle. The lateral femoral condyle, tibial plateau and meniscus were normal. The medial femoral condyle had some Grade III changes. The medial meniscus had a complex posterior horn tear.

Using basket forceps and a motorized shaver, a subtotal medial meniscectomy was carried out. A generous chondroplasty and a very limited medial synovectomy of the femoral condyle were performed. The joint was thoroughly irrigated, infiltrated with Marcaine and a sterile dressing was applied.

The patient tolerated the procedure well and was transferred to the recovery room in satisfactory condition with her neurovascular status of the extremity normal.

ICD-9-CM CODE ASSIGNMENTS

Preoperative ICD-9-CM Diagnoses:

717.3 Other and unspecified derangement of medial meniscus

727.00 Synovitis and tenosynovitis, unspecified

Postoperative ICD-9-CM Diagnoses:

717.2 Derangement of posterior horn of medial meniscus

733.92 Chondromalacia

727.00 Synovitis and tenosynovitis, unspecified

717.7 Chondromalacia of patella

CPT Code Assignments and Rationale

When assigning CPT codes for anesthesia services, you must first determine the type of anesthesia being administered and by whom. Once you have determined these two items, you can begin to assign the appropriate codes. Medicare requires you to assign one anesthesia code(s) for surgical procedures, while most other payers require assignment of the primary or principle surgical code.

The best way to determine codes for anesthesia services is to first assign the surgical CPT codes. In the case above, you would go to the index and check under the boldface term Arthroscopy. As this was a surgical procedure, and not diagnostic (one of the other options listed), you will look under Surgical and then the indented term Knee, which lists 29871-29889 as the choices.

A review of the codes in the CPT book shows that the following is the correct code to assign for the above case study.

29881 Arthroscopy, knee, surgical; with meniscectomy (medial OR lateral, including any meniscal shaving)

Next, go to Anesthesia in the CPT manual index, then to the term Arthroscopic Procedures. Checking the indented terms, you will find the word Knee followed by 01382, 01400. Review the descriptions for these codes and you will see that the fol-lowing is the correct choice.

01400 Anesthesia for open or surgical arthroscopic procedures of knee joint; not otherwise specified

No anesthesiologist was present at this procedure. Therefore, modifier QZ would be assigned to reflect that a non-medically directed CRNA provided the anesthesia service.

QZ CRNA service without medical direction by a physician

If this were a Medicare patient, you would then “crosswalk” the CPT surgical code 29881 to the appropriate CPT anesthesia code. (This crosswalk is published yearly by the American Society of Anesthesiologists.) Code 29881 crosswalks to 01400 to which you would assign modifier QZ.

For Medicare, assign the following:

01400-QZ Anesthesia for open or surgical arthroscopic procedures of knee joint; not otherwise specified

For other (non-Medicare) payers, assign the following:

29881 Arthroscopy, knee, surgical; with meniscectomy (medial OR lateral, including any meniscal shaving)

The assignment of the QZ modifier is required by Medicare. Other third-party payers may or may not want this modifier, so be sure to verify this requirement with your specific payer.

Kathleen Mundy is manager of consulting services, Physician Division, with Medical Learning, Inc. (MedLearn®), St. Paul, MN.