Does T58.91XD require prior authorization?

No, T58.91XD does not require prior authorization (high confidence). Code is covered without prior authorization.

`T58.91XD` — Toxic effect of carbon monoxide from unspecified source, accidental (unintentional), subsequent encounter

ICD-10-CM

No Prior Auth Required

Code is covered without prior authorization (high confidence)

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.
When a limited or follow-up echocardiogram is performed, document the targeted cardiac problem/region and bill using the appropriate CPT code (93308 or 93321).
If the study is a screening exam, document and bill with the appropriate screening ICD-10 code; document any abnormal findings and use the resulting diagnosis for subsequent billing when applicable.
Document use of ultrasound contrast enhancement and its supplies separately when billed, and do not submit separate claims for diagnostic injection services integral to the contrast procedure.

Follow-up or limited transthoracic echocardiography performed to evaluate a single specified cardiac problem or region must be billed with CPT 93308.
Limited Doppler/follow-up echocardiographic studies (for targeted velocity or gradient assessment) should be billed with CPT 93321 (e.g., tricuspid regurgitant velocity to estimate pulmonary artery systolic pressure or sequential transmitral velocity in mitral stenosis).
Cranial CT (with or without contrast) is covered when the patient has clinical evidence of an intracranial disorder or an established intracranial disorder/disease.
Contrast-enhanced CT is reasonable and necessary to assess cerebral perfusion, for example in suspected or known cerebrovascular accident (CVA).
Contrast-enhanced CT is covered to characterize a specific intracranial lesion.
Contrast-enhanced CT is covered to detect blood–brain barrier defects such as infarcts, tumors, infection, or vasculitis.

A56612 — Billing and Coding: CT of the Head

A56625 — Billing and Coding: Echocardiography

L34417 — CT of the Head

L37379 — Echocardiography

Ask Verity about documentation requirements, denial risks, or coverage in your state.