PFTs (Pulmonary Function Tests) are important tools in the diagnosis of respiratory maladies, enabling the clinician to evaluate lung capacities, air flow efficiency, and gas exchange. Proper coding and billing of these tests become indispensable for any healthcare firm wishing to receive legitimate claims while staying in compliance with payer-specific stipulations. This guide tackles the specific minutiae involved in CPT and ICD-10-CM coding as applied to PFTs, tailored for an audience that includes pulmonologists, PCPs, and medical billing specialists.
Basic Principles of Pulmonary Function Testing
The major aim of PFTs lies in assessing different abnormal diagnoses related to conditions such as asthma, chronic obstructive pulmonary disease (COPD), and interstitial lung diseases. Thus, the tests, in general, have five major methods: spirometry, lung volume assessment, diffusion capacity assessment, bronchial provocation, and cardiopulmonary stress testing. Each test type corresponds to specific Current Procedural Terminology (CPT®) codes that reflect the technical complexity and clinical intent of the procedure.
Clinical Actionability for PFTs
PFTs are generally indicated when one has symptoms of dyspnea, chronic cough, or exercise intolerance and also during the follow-up of a known respiratory ailment. Preoperative risk stratification and occupational health programs are also very common applications. The choice of a specific test depends upon the considerations for the suspected pathology, with spirometry being the first-line test for obstructive lung diseases, while diffusion capacity testing would be most important in the evaluation of restrictive pathologies12
Implementation of CPT Codes for Different Pulmonary Function Testing Modalities
Spirometry Protocols
Spirometry remains the backbone of pulmonary diagnostics, measuring forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). The CPT system distinguishes between simple and advanced spirometry. The differentiating codes are:
- CPT 94010: Basic spirometry without bronchodilator administration documenting FVC and FEV1.
- CPT 94060: Pre- and post-bronchodilator spirometry in assessing reversible airflow obstruction crucial in diagnosing asthma.
- CPT 94070: Bronchial challenge testing using methacholine or mannitol to evaluate airway hyper-responsiveness, usually coded together with spirometry if performed subsequently12.
Difficult situations could often prompt the use of CPT 94200 (maximal voluntary ventilation) to assess respiratory muscle endurance, especially in evaluating patients with neuromuscular disease.
Lung Volume Quantification Techniques
Different methods are used to measure total lung capacity (TLC) and residual volume (RV). The body plethysmography (CPT 94726) is a less accurate measurement of expiration volume than a gas dilution method (CPT 94013). Therefore in obesity-related breathing disorders, lung plethysmography is given high priority since it is accurate in the detection of air trapping. In contrast, in children, the dilutional nitrogen methods may be preferred.
Diffusion Capacity Studies
The single-breath test for carbon monoxide diffusion capacity (CPT 94729) measures the integrity of the alveolar-capillary membrane by DLCO values. Clinicians conducting interpretation must document hemoglobin levels, as anemia can spuriously lower DLCO values. This examination is considered indispensable in the evaluation of pulmonary hypertension and interstitial lung diseases.
Bronchoprovocation Testing
Bronchial challenge testing is governed by both the CPT codes 95070 and 95071, with the latter being applicable for subsequent tests performed on that same day. Properly documented must be the provoking agent (e.g., methacholine, exercise), response thresholds, and the clinical rationale for conducting the test12
Cardiopulmonary Exercise Test-CPET
CPET considers ventilatory and cardiovascular measurements during exertion (CPT 94679-94681). Selected codes depend on the monitoring’s complexity:
- 94680: Basic exercise oximetry.
- 94681: Advanced metabolic gas analysis including ventilatory threshold determination.
Medicare Compliance and Medical Necessity
The hellish standards of medical necessity that PFTs are held to get approval for reimbursement by CMS are not simple. Services covered must be expected to show relevance to any of the following:
- Initial diagnosis of suspected respiratory pathology
- Quantification of disease severity for disability determinations
- Preoperative risk assessment protocols for thoracic surgeries
- Monitoring purposes to evaluate therapeutic benefit of biologics (e.g., nintedanib in IPF)
Coding combinations put out by Medicare entail:
- 94010 + 94729, in COPD follow-up
- 94726 + 94727 + 94729, in interstitial lung disease panels
Documentation must directly link the test result to the clinical decision-making process and must avoid routine surveillance testing lacking any symptoms or functional changes12.
ICD-10-CM Diagnostic Mapping
Accurate diagnosis coding requires precise orientation in fulfilling PFT indications:
Obstructive Lung Diseases
- J44.9: COPD, unspecified
- J45.909: Unspecified asthma, uncomplicated
Restrictive Lung Diseases
- J84.112: Idiopathic pulmonary fibrosis
- J84.9: Interstitial lung disease, unspecified
Occupational Lung Disorders
- J68.9: Unspecified respiratory conditions due to chemical vapors
- J70.5: Acute pulmonary toxicity due to radiation
Specific codes should not be used as an independent justification for complex PFT panels12.
Operational Best Practices
Documentation Standards
- Spirometry tracings must fulfill the American Thoracic Society (ATS) acceptability criteria.
- DLCO reports reference hemoglobin-adjusted values as well.
- Exercise test protocols should require a detailed description of the methodology.
Codings Audits
Quarterly audits should include a focus on:
- Code bundling errors (e.g. billing for 94010 and 94726 separately when done in conjunction)
- The misuse of modifier -59 in bronchoprovocation sequences
- Medical necessity concerning local coverage determinations (LCDs)
Technology Integration
Now pulmonary labs may be doing things as fairly integrated systems of EHR-PFTs, which automatically:
- Populate clinical indications from structured data.
- Perform Correct Coding Initiative (CCI) edits in real time.
- Report to patients in a user-friendly way, including guidelines for interpretation.
Revantage Healthcare Solutions in Pulmonary Practice Revantage Health streamlines pulmonary billing:
- Compliance-First Coding
Our certified coders sustain a 98% accuracy rate through ongoing education on CMS updates as well as the ATS/ERS technical standards.
- Denial Management
Proactive appeal strategies bring back 85% of initially denied claims through:
- Payer-to-peer discussions with insurers
- Supplemental collection of clinical information
- Coupling regulatory citations to appeal letters
- Revenue Cycle Analytics
Custom dashboards track:
- Payer-specific approval timelines
- Test utilization patterns versus benchmarks
- Modifier effect on reimbursement rates
- Provider Education
Bi-monthly webinars deal with:
- Documentation improvement strategies
- Novel PFT technologies (e.g., impulse oscillometry coding)
- Telehealth-integrated home spirometry billing
Conclusion
Effectively driving PFT coding requires a dual focus on technical code application and changing regulations. The increasing pressure on payer policies to seek outcome-based justification for diagnostic testing mandates providers to follow very granular documentation practices and be well-disciplined in their billing system. This, in turn, allows for their timely payment from claims. Thus, joining forces with a specialized revenue cycle management company such as Revantage Healthcare assures the financial viability of pulmonary practices while they concentrate their maximum potential on new ways of innovating patient care.
For personalized consultation on optimizing your pulmonary function test reimbursement, contact Revantage Healthcare at info@revantagehbs.com or (925) 217-8110.
Note: CPT is a registered trademark of American Medical Association
Reference: https://www.medisysdata.com/
