Where this LCD applies
Each contract number is a jurisdiction on the remittance; the policy binds claims processed under these contracts and no others.
Billing and coding: diagnoses and procedure codes
Since 2019 the codes live in the companion article rather than the LCD. Billing and Coding A57224 (Billing and Coding: Respiratory Care) carries the diagnosis and procedure lists the contractor loads as the claims edit. CPT codes are shown as bare numbers because the descriptors are licensed by the AMA; HCPCS Level II descriptors are public and shown.
A57224: Billing and Coding: Respiratory Care (Billing and Coding, effective 2026-01-01)
- Covered ICD-10-CM codes
- 901
- 1 group
- Non-covered ICD-10-CM codes
- 0
- Procedure codes listed
- 37
- Full article
- cms.gov record
| ICD-10-CM | Description (FY2027) |
|---|---|
| A15.0 | — |
| A15.4 | — |
| A15.5 | — |
| A15.6 | — |
| A15.7 | — |
| A15.8 | — |
| A18.01 | — |
| A19.0 | — |
| A19.1 | — |
| A19.8 | — |
| A20.2 | — |
| A20.7 | — |
| A22.1 | — |
| A31.0 | — |
| A36.2 | — |
| A37.00 | — |
| A37.01 | — |
| A37.10 | — |
| A37.11 | — |
| A37.80 | — |
| A37.81 | — |
| A42.0 | — |
| A43.0 | — |
| A52.72 | — |
Procedure codes: 31502, 31720, 94002, 94003, 94004, 94010, 94011, 94012, 94013, 94060, 94070, 94150, 94200, 94375, 94450, 94617, 94618, 94619, 94621, 94640, 94642, 94660, 94664, 94667, 94668, 94669, 94680, 94681, 94690, 94726, 94727, 94728, 94729, 94772, G0237 (Therapeutic Procedures To Increase Strength Or Endurance Of Respiratory Muscles, Face To Face, One On One, Each 15 Minutes (Includes Monitoring)), G0238 (Therapeutic Procedures To Improve Respiratory Function, Other Than Described By G0237, One On One, Face To Face, Per 15 Minutes (Includes Monitoring)), G0239 (Therapeutic Procedures To Improve Respiratory Function Or Increase Strength Or Endurance Of Respiratory Muscles, Two Or More Individuals (Includes Monitoring)).
Coverage indications, limitations and medical necessity
Respiratory care (respiratory therapy) is defined as those services prescribed by a physician or a non-physician practitioner for the assessment and diagnostic evaluation, treatment, management, and monitoring of patients with deficiencies and abnormalities of cardiopulmonary function.
Monitoring is defined as the periodic checking of the equipment in actual use to ascertain proper functioning; real time tracking the individual’s condition to assure that he/she is receiving effective respiratory therapy services; and periodic evaluation of the patient’s progress in improvement of respiratory function.
Respiratory care (respiratory therapy) services may include but are not limited to the following:
• application techniques to support oxygenation and ventilation in an acute illness (e.g., establish/maintain artificial airway, ventilatory therapy, precise delivery of oxygen concentrations, aid in removal of secretions from pulmonary tree)
• therapeutic use/monitoring of medicinal gases, pharmacologically active mists and aerosols, and equipment (e.g., resuscitators, ventilators)
• bronchial hygiene therapy (e.g., deep breathing, coughing exercises, IPPB, postural drainage, chest percussion/vibration, and nasotracheal/endotracheal suctioning)
• diagnostic tests ordered by and for the evaluation by a physician or NPP (e.g., pulmonary function test, spirometry, and blood gas analyses etc.)
• pulmonary rehabilitation techniques (e.g., exercise conditioning, breathing retraining, and patient education regarding management of patient’s respiratory problems) and
• periodic assessment of the patient for the effectiveness of respiratory therapy services.
For Pulmonary Rehabilitation services, please refer to Noridian's Billing and Coding: Pulmonary Rehabilitation Services Local Coverage Article under Related Documents at the end of this policy.
The above services may be performed by respiratory therapists, physical therapists, nurses, and other qualified personnel as described by relevant state practice acts. Documentation in the medical record must clearly support the need for respiratory therapy services to be separately reimbursed.
Respiratory care (respiratory therapy) services can be considered reasonable and necessary for the diagnosis and treatment of a specific illness or injury. The service provided must be consistent with the severity of the patient’s documented illness and must be reasonable in terms of modality, amount, frequency, and duration of treatment. The treatment must be generally accepted by the professional community as safe and effective for the purpose used, and recognized standards of care should not be violated.
Medicare coverage of respiratory care (respiratory therapy) provided as outpatient hospital or extended care services depends on the determination by the attending physician (as part of his/her plan of treatment) that for the safe and effective administration of such services the procedures or exercises in question need to be performed by a respiratory therapist, physical therapists, nurses, and other qualified personnel as described by relevant state practice acts as listed above. In addition, Medicare may cover postural drainage and pulmonary exercises furnished by a respiratory therapist as incident to a physician's professional service.
Instructing a patient in the use of equipment, breathing exercises, etc. may be considered reasonable and necessary for the treatment of the patient’s condition and can usually be given to a patient during the course of treatment by any of the health personnel involved, (e.g., physician, nurse, respiratory care practitioner or other qualified personnel). These educational instructions are bundled into the covered service and separate payment is not made. Separate billing for one-on-one education is rarely necessary and is usually only reasonable at the start of the treatment plan. Initially, for outpatient care where a series of visits provides “… an individualized physical conditioning and exercise program using proper breathing techniques…” separate billing for one-on-one intervention is both reasonable and necessary. Provision of more information than is ordinarily provided during the course of a treatment (e.g., extensive theoretical background in the pathology, etiology, and physiological effects of the disease) is not considered reasonable and necessary. Group sessions that only offer generalized (i.e., non-individualized) education and training are not covered.
Therapeutic procedures with an individualized physical conditioning and exercise program using proper breathing techniques can be considered for a patient with activity limitations. Breathing retraining, energy conservation, and relaxation techniques are often used. Ventilatory muscle training (VMT) may be considered reasonable and necessary in a very select population of pulmonary patients who demonstrate significantly decreased respiratory muscle strength and who remain symptomatic despite optimal therapy. Routine exercise, or any exercise, without a documented need for skilled care, is not covered.
Pulmonary Function Tests
Pulmonary Function Tests (PFTs) are a broad range of diagnostic procedures that measure two components of the respiratory system's functional status: 1) the mechanical ability to move air in and out of the lungs, and 2) the effectiveness of providing oxygen to the body and removing carbon dioxide.
Pulmonary function tests are divided into five general areas:
• Spirometry,
• Lung Volume,
• Diffusion Capacity,
• Lung compliance, and
• Pulmonary Studies during Exercise Testing.
General indications for any of the pulmonary function tests include:
• To determine the presence of lung disease or abnormality of lung function;
• To determine the type of abnormality;
• To determine the extent of abnormality;
• To determine the extent of disability due to abnormal lung function, and
• To determine and evaluate one or more courses of therapy in the treatment of the particular condition.
General limitations for any of the pulmonary function tests include:
• All diagnostic tests payable by Medicare must be ordered by a treating physician and used in patient care. Community standards always apply.
• The various modalities to assess pulmonary function must be used in a purposeful and logical sequence.
• Tests performed as components rather than a single test will be denied.
• Medicare does not cover screening tests. Medicare coverage excludes routine (screening) tests for asymptomatic patients with or without high risk of lung disease (e.g., prolonged smoking history). It also excludes studies as part of a routine exam, and studies as part of an epidemiological survey.
Medical necessity is an overriding requirement for Medicare coverage of diagnostic testing. When a diagnosis or evaluation can be made clinically or when test results are not necessary to manage the patient's disease, then Pulmonary Function Testing is not reasonable and necessary. In addition, on routine visits for other medical conditions, when a patient claims to be stable or does not report clinically meaningful changes in pulmonary status, a physical exam and interview confirm this, repeat testing is unlikely to be necessary. Noridian has found that in many patients routine use of PFTs at each office visit is not a necessary and reasonable clinical practice and as such, cannot be reimbursed.
Providers should pay particular attention to guidelines for the usage of the CPT codes relative to Medicare's standards of reasonable and necessary care found in the Billing and Coding article attached under Related Local Coverage Documents below.
1. Spirometry:
Spirometry is performed by having the patient breathe into a mouthpiece that is connected to an instrument called a spirometer. The spirometer records the amount of air and the rate that it is breathed in and out over a specified amount of time (approximately 10 seconds). Some of the test measurements are obtained by normal breathing and other measurements require forced inhalation and exhalation.
Spirometry is most useful for assessing obstructive lung diseases such as asthma and chronic obstructive pulmonary disease (COPD).
Refer to the Billing and Coding article attached under Related Local Coverage Documents below for the CPT codes for Spirometry. Routine and/or repetitive billing for unnecessary batteries of tests is not clinically reasonable.
Specific indications for spirometry include:
Diagnostic indications:
• Detect the presence or absence of lung dysfunction suggested by history or clinically significant physical signs and symptoms,
• Detect the presence or absence of lung dysfunction suggested by other abnormal diagnostic tests (e.g., radiography, arterial blood gas analysis).
Monitoring indications:
• Quantify the severity of known lung disease,
• Assess the change in lung function over time,
• Assess the change in lung function following administration of or a change in therapy,
• Assess the risk for surgical procedures known to affect lung function.
Limitations to performing spirometry are:
• Routine or repetitive batteries of tests are not clinically reasonable.
• In many scenarios, simple spirometry is a mainstay of pulmonary function testing and is usually sufficient to differentiate between obstructive and restrictive disorders and evaluate their severity. Extensive testing may often not be necessary for adequate clinical assessment.
• Post-bronchodilator spirometry is used to evaluate the reversible component of bronchospasm and to determine if the patient is a bronchodilator therapy candidate. Claims for spirometry will be subject to medical review as follows: there are clinical signs and symptoms consistent with bronchospasm; or spirometry without bronchodilator is abnormal; or reversibility or nonreversibility of bronchospasm has not been demonstrated. Repeat studies are covered only with clinically significant change, necessitating adjustment/augmentation of therapy, appropriately documented.
• General clinical contraindications to spirometry include: hemoptysis of unknown origin, pneumothorax, unstable cardiovascular status, thoracic/abdominal or cerebral aneurysms, recent eye surgery, recent thoracic or abdominal surgery, and presence of acute disease processes that interfere with test performance.
2. Lung volume
The entire lung volume is not measured by simple spirometry because it is larger than the air quantity exhaled/inhaled. Lung volume is measured when a person breathes nitrogen or helium gas through a tube for a specified period of time. The change in concentration of the gas in a chamber attached to the tube is measured before and after test breathing, allowing estimation of the lung volume. Measures include total lung capacity, residual volume, and functional residual capacity.
Lung volume tests are most useful for assessing restrictive lung diseases such as those caused by scarring inside the lungs or by abnormalities in the ribcage or muscles of the chest wall.
CPT codes for lung volume determination may be added when clinically relevant (see Section 4).
Indications for a lung volume test are as follows, when consistent with community standards of reasonable clinical practice:
• Evaluation of the type and degree of pulmonary dysfunction,
• Evaluation of dyspnea, cough, and other symptoms,
• Early detection of lung dysfunction,
• Follow-up and response to therapy,
• Preoperative evaluation,
• Track pulmonary disease progression,
• Assess the effectiveness of therapy for pulmonary conditions,
• Pre and post-op evaluations for Lung Volume Reduction Surgery (LVRS).
Limitations to performing a lung volume test are:
• Functional Residual Capacity (FRC) may be artificially high if the measurement is taken at a higher lung volume secondary to pain or anxiety,
• Subject cooperation is necessary,
• A complete evaluation may require the use of inhaled gases,
• Repetitive testing of total lung volume is not usually clinically necessary.
3. Diffusion Capacity
Diffusion capacity is measured when a person breathes in a measured amount of carbon monoxide for a very short time (often just one breath). While breathing out, the concentration of carbon monoxide is measured. The difference in the amount of carbon monoxide inhaled and the amount exhaled allows estimation of how rapidly gases can travel from the lungs into the blood.
Diffusion capacity tests are most useful for the assessment of how well the lung tissues transfer oxygen from the air inside the lungs, across thin membranes, into the blood.
Indications for diffusion capacity (DLCO) are as follows, when consistent with community standards of reasonable clinical practice:
• Evaluate and follow up parenchymal lung diseases associated with dusts or drug reactions or Sarcoidosis,
• Evaluate and follow up emphysema and cystic fibrosis,
• Differentiate between chronic bronchitis, emphysema, and asthma in patient with obstructive patterns,
• Evaluate the pulmonary involvement in systemic diseases (e.g., rheumatoid arthritis, systemic lupus),
• Help in the evaluation of some types of cardiovascular disease (e.g., primary pulmonary hypertension, pulmonary edema, acute or recurrent thromboembolism),
• Predict arterial desaturation during exercise in chronic obstructive pulmonary disease,
• Evaluate and quantify the disability associated with interstitial lung disease,
• Evaluate the effects of chemotherapy agents or other drugs known to induce pulmonary dysfunction,
• Evaluate hemorrhagic disorders.
Limitations to performing a diffusion capacity test are:
• Mental confusion or muscular incoordination preventing the subject from adequately performing the maneuver,
• Single breath DLCO requires breath holding at maximal inhalation. Some patients may be limited by syncopal symptoms triggered by an associated Valsalva or Muller maneuver which may slow the heart rate.
4. Lung Compliance
Lung compliance studies are performed only when all other PFTs give equivocal results or results which must be confirmed by additional lung compliance testing. Lung compliance measures the elastic recoil/stiffness of the lungs. It is more invasive than other PFTs, because the patient is required to swallow an esophageal balloon.
The policy text continues in the CMS record.
Summary of evidence (opening)
NA
the full summary and analysis of evidence are in the CMS record.
Dates, lineage and related policies
- Original determination effective
- 2015-10-01
- Current revision effective
- 2025-10-16
- Last reviewed by the contractor
- 2023-11-08
- MCD version
- 52
The contractor lists 2 National Coverage Determinations as related: NCD 240.7 Postural Drainage Procedures and Pulmonary Exercises, NCD 240.8 Pulmonary Rehabilitation Services. Where an NCD speaks, it controls; the LCD can only address what the NCD leaves open.
Other related documents: A59531 (Response to Comments), A59532 (Response to Comments).
Using this policy on a claim
Match the documented indication to the covered indications above before the service is scheduled, carry a diagnosis from the article's covered list on the claim line, and keep the elements the documentation section asks for in the record, because the contractor can request it later through medical review. A denial under this policy arrives as CARC 50 with remark N115; the LCD lookup guide walks through the appeal path and the Advance Beneficiary Notice rules, and the Noridian Healthcare Solutions, LLC hub lists every other active policy from the same contractor.
Frequently asked questions
What does LCD L34149 cover?
Respiratory care (respiratory therapy) is defined as those services prescribed by a physician or a non-physician practitioner for the assessment and diagnostic evaluation, treatment, management, and monitoring of patients with deficiencies and abnormalities of cardiopulmonary function. The full indications and limitations are reproduced on this page from the CMS Medicare Coverage Database export of September 24, 2026.
Which states does LCD L34149 apply to?
Noridian Healthcare Solutions, LLC applies it to Medicare claims in AK, AS, AZ, CA, CNMI, GU, HI, ID, MT, ND, NF, NV, OR, SD, SF, UT, WA, WY. A Local Coverage Determination binds only the contractor that wrote it; the same service in another jurisdiction is judged under that contractor's own policy or, where none exists, claim by claim.
Which diagnosis codes support medical necessity under LCD L34149?
The companion billing and coding article A57224 lists 901 ICD-10-CM codes in 1 group that support medical necessity; the first 24 appear on this page and the complete list is in the article on cms.gov.
How do I appeal a denial under LCD L34149?
The remittance carries claim adjustment reason code 50 with remark code N115, naming the LCD. Compare the documented indication with the policy's covered indications and the article's diagnosis list, then file a redetermination within 120 days with the record attached; if the service genuinely falls outside the policy, the patient can be billed only when a valid Advance Beneficiary Notice was obtained before the service.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-02. Verify against the primary file before billing or contracting decisions.
- Medicare Coverage Database, current LCD exportVersion MCD release 2026-09-24 · effective 2026-09-20 · file lcd.csvSHA-256 2fcc4251b6ddd1eb…
- Medicare Coverage Database, current Billing and Coding Articles exportVersion MCD release 2026-09-24 · effective 2026-09-20 · file article.csvSHA-256 f31932f1df3b4035…
- ICD-10-CM FY2027 code descriptionsVersion FY2027 · effective 2026-10-01 · file icd10cm_codes_2027.txtSHA-256 3c0583a38ee0e848…
Disclaimer
The policy text and code lists are reproduced from the CMS Medicare Coverage Database export as an operational reference. Verify against the current LCD and article on cms.gov before billing; coverage depends on the full record and the contractor. Not legal, clinical or billing advice.