T59.4X4D — Toxic effect of chlorine gas, undetermined, subsequent encounter
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- This article provides billing/coding guidelines that complement Local Coverage Determination L34417 for CT of the head; consult LCD L34417 for specific coverage, coding, and documentation requirements.
- A specific written order (referral/prescription) by the physician or appropriate NPP must be on file for all respiratory care services.
- Medical records must fully document that services were reasonable and medically necessary, with results and usage of the test documented in the record and available upon request.
- Each claim must be submitted with ICD-10-CM code(s) that reflect the patient's actual condition; listing a diagnosis code alone does not justify the test without supporting clinical context.
Key Coverage Criteria
- Therapeutic respiratory procedures (HCPCS G0237, G0238, G0239) using an individualized physical conditioning and exercise program with breathing techniques are covered for patients with documented activity limitations.
- Pulmonary function tests (PFTs) represented by CPT codes 94070, 94200, 94640, 94726, 94727, and 94729 are covered when reasonable and medically necessary with supporting clinical documentation and a written order by a physician or appropriate NPP.
- Spirometry (CPT 94010, 94011, 94012, 94060, 94070, 94150, 94200, 94375, 94726, 94727) is covered when clinically indicated and documented in the medical record.
- Lung volume determination (CPT 94013, 94726, 94727, 94728) and diffusion capacity testing (CPT 94729) are covered when medically necessary and documented.
- Pulmonary stress testing (CPT 94617, 94618, 94619, 94621) is covered when clinically indicated and supported by the medical record.
- Device demonstration and/or evaluation (CPT 94664) is covered when used for device demonstration/evaluation purposes and documented as such in the medical record.
6 Active Policies
A57225 — Billing and Coding: Respiratory Care
A56612 — Billing and Coding: CT of the Head
A57224 — Billing and Coding: Respiratory Care
L34417 — CT of the Head
L34149 — Respiratory Care
Related Codes
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