Crit-Line In-Line Monitor
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This policy describes Aetna's coverage stance for the Crit-Line in-line monitor used to measure hematocrit and oxygen saturation during hemodialysis and which members/providers it affects.
No material clinical or coverage changes in this revision.
Coverage Determination
Not established as medically necessary / investigational
Aetna's coverage conclusion for the Crit-Line In-Line Monitor
Statement of noncoverage stance based on insufficient evidence.
Use of the Crit-Line In‑Line Monitor for monitoring hematocrit and oxygen saturation is considered experimental and investigational and is excluded from coverage under this policy.
The device is considered investigational because the effectiveness of the Crit‑Line In‑Line Monitor in avoiding intra‑dialytic morbid events, in preventing ischemia due to intra‑dialytic hypoxia, and in determining access re‑circulations has not been demonstrated. Clinical reports (for example Steuer et al.) have evaluated blood‑volume monitoring and tolerance of additional fluid removal but do not establish that use of the Crit‑Line reduces intradialytic morbidity or prevents ischemic events.
Coding and Billing
| 90935 | Hemodialysis procedure with single evaluation by a physician or other qualified health care professional. |
| 90937 | Hemodialysis procedure requiring repeated evaluation(s) with or without substantial revision of dialysis prescription. |
| S9335 | Home therapy, hemodialysis; administrative services, professional pharmacy services, care coordination, and all necessary supplies and equipment (drugs and nursing services coded separately), per diem. |
| N17.0 - N17.9 | Acute kidney failure. |
| N18.1 - N18.9 | Chronic kidney disease (CKD). |
| N19 | Unspecified kidney failure. |
| N26.1 | Unspecified contracted kidney. |
| N26.9 | Unspecified contracted kidney. |
| Z49.31 | Encounter for adequacy testing for hemodialysis. |
| Z49.32 | Encounter for adequacy testing for peritoneal dialysis. |
| Z99.2 | Dependence on renal dialysis. |
Provider Notice, Authorization & Billing Guidance
Denial Risk for Use
The Crit-Line In-Line Monitor is considered experimental and investigational for monitoring hematocrit and oxygen saturation because its effectiveness for avoiding intra-dialytic morbid events, preventing ischemia due to intra-dialytic hypoxia, and determining access re-circulations has not been proven. Use of this device may be denied as not medically necessary.
- Experimental / investigational for monitoring hematocrit and oxygen saturation
- May be denied for the uses described due to insufficient evidence
Prior Authorization Not Specified
Aetna does not specify any prior authorization codes or prior authorization procedure for the Crit-Line In-Line Monitor in this policy. Providers should follow standard plan-specific prior authorization processes when applicable and verify requirements with the member's benefit plan.
- No specific prior authorization codes listed in this policy
- Verify member-specific prior authorization requirements with the plan
Provider Documentation / Authorization Absence
No provider documentation or authorization instructions are provided in this policy. Providers must retain appropriate medical records to support services rendered and consult the member's plan for any documentation or authorization requirements.
- No policy-level documentation or authorization steps described
- Maintain clinical records to justify medical necessity if services are rendered
Step Therapy Not Specified
There are no step therapy requirements described for the Crit-Line In-Line Monitor in this policy.
- No step therapy or prior treatment sequence required per this policy
Coding and Documentation References
Relevant coding references listed in the source include related hemodialysis and home therapy codes. ICD-10 diagnosis codes are listed as not covered for indications in the CPB (examples include acute and chronic kidney failure codes). Providers should bill using the applicable hemodialysis procedure or HCPCS codes when appropriate and note that no specific CPT/HCPCS code is designated for the Crit-Line device itself.
Provider Guidance / Additional Information
This policy does not provide provider-facing actions beyond the above notices. For additional information, refer to Aetna clinical policy resources and the member's benefit plan documents.
- See Aetna Clinical Policy Bulletins and plan-specific documents for more information
Device Background
The Crit‑Line In‑Line Monitor is an optical, in‑line monitoring system that measures hematocrit and oxygen saturation in real time by placing a sterile disposable blood chamber and sensor in‑line between the arterial tubing and the dialyzer. Readouts include hematocrit, percent blood‑volume change, and oxygen saturation displayed graphically during hemodialysis.
Definitions and Key Terms
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