On the surface, coding preoperative evaluation visits is straightforward: choose the E/M code that best reflects your medical decision-making. The details of medical billing decide what is payable in the outpatient setting and help you avoid payer scrutiny, says AAPC's Raemarie Jimenez: "It's one thing to go through the steps for good clinical care," she says. "It's another thing as to when it's a billable service."

Jimenez provides the following 5 best practices to help coders report preoperative visits correctly using pre-op CPT (current procedural terminology) codes and avoid costly denials.

The purpose of a preoperative visit is to evaluate a patient's complicating health condition to determine whether they can withstand surgery. Healthy patients don't generally require a preoperative examination. 

Surgeons may evaluate healthy patients to determine whether surgery is necessary. However, they don't typically need to send these patients to a primary care physician, internist, or specialist to clear them for the surgery.

Typical candidates for clearance include those with cardiovascular risk, hypertension, or pulmonary disease. When concerns arise, healthcare professionals coordinate perioperative risk assessment with primary care and, when indicated, a cardiologist, and document whether care will occur in an outpatient or inpatient setting to support safe patient care.

Specialists and internal medicine physicians most often perform pre-op clearance because they manage conditions that could affect anesthesia or recovery. When criteria are met, a separate office visit may be reportable with the right documentation, procedure codes, and management services that support medical necessity.

Once the decision to operate is made, the surgeon's related pre-op work falls under global surgery. The global surgical package includes preoperative visits after that decision, the day before a major procedure, and the day of surgery for a minor procedure. Attempts to unbundle these services can put reimbursement at risk.

The surgeon's routine history and physical is included in the package and isn't separately billable. For example, if a patient delays surgery and the surgeon brings the patient back into the office for an evaluation the day before, that visit is typically bundled.

Use modifier guidance correctly. Modifier -57 applies when the visit documents the first decision for a major surgery on the day of, or the day before, surgery. Modifier -24 applies to unrelated E/M during the postoperative period, but it does not make a routine pre-op H&P separately payable. Policies can vary across Medicare and Medicaid contracts, so confirm plan terms before billing.

 Visits for preoperative clearance require ICD-10-CM codes that denote the following information:

Sequence Z01.81x first, then the surgery reason, then comorbidities. Doing this signals to payers that the visit's primary purpose is a pre-op exam (per FY 2025 ICD-10 guidelines).

Consider this example: A patient with COPD exacerbation is sent for knee surgery due to right knee osteoarthritis. Report an E/M for the visit and: Z01.811 (encounter for preprocedural respiratory examination), M17.11 (unilateral primary osteoarthritis, right knee), J44.1 (COPD with acute exacerbation). Then, update the medical record to reflect your pre-op evaluation rationale.

You may report more than one Z code when multiple systems are evaluated. For cardiac risk, add Z01.810 (preprocedural cardiovascular exam) and, if laboratory tests are central, use Z01.812. Then list the surgical indication, followed by the comorbidity diagnoses (e.g., arrhythmia) assessed for preoperative clearance.

To justify medical necessity, make sure your notes clearly support the service provided and the setting.

Documentation should include:

Clear, specific documentation helps teams across healthcare verify the rationale and withstand audit review.

Visits for pre-op clearance are separate from a decision for surgery. The latter is an outpatient E/M encounter where the clinician decides to proceed with a major operation and documents why.

Report the E/M with modifier -57 when the decision occurs on the day of, or the day before, a major surgery. If the visit happens earlier, modifier -57 isn't required. Choose the level that fits the note, whether the patient is new or an established patient.

Policies can differ by payer. Some follow CMS rules on consultation codes, while others still accept them. Verify plan requirements and, if needed, reference the CMS MLN Evaluation & Management Services guide for policy notes and level selection.

Start with sequencing. Lead with Z01.81x, then add the diagnosis for the planned procedure and any comorbidities assessed during pre-op clearance. That order helps payers understand intent and keeps your note aligned with policy.

Back it up in the chart. Document medical necessity with pertinent history, physical exam, and laboratory tests, and make the level of medical decision-making clear for the E/M service. Small details in wording and structure often decide whether a claim is payable.

Respect packaging rules. Under global surgery, preoperative visits after the decision to operate are included. This should be the day before a major procedure and the day of surgery for a minor procedure. Use modifier -57 only when the first decision for a major surgery is made on those dates.

Standardize the process. Build templates in your EHR for pre-op evaluation and routing, and use the medical billing software and workflows from Tebra to streamline submissions and reduce preventable denials.