Acute Inpatient Hospital Services
Customize your policy alerts
Sign up for Montana Department of Public Health & Human Services Policy 470 alerts
Get alerted when Policy 470 changes without checking for updates manually.
Monitor payer policy activity
Defines coverage, medical necessity, provider and service requirements, and utilization management for acute inpatient psychiatric hospital services for Montana Medicaid members, including prior authorization rules for out-of-state placements.
No material clinical or coverage changes in this revision.
Coverage and Medical Necessity Criteria
inv-01: Admission (Medical Necessity) Criteria
Covered when ALL of the following are met
inv-02: Continued Stay Criteria
Continued stay covered when ALL of the following are met
For out-of-state facilities, the department or UR Contractor may issue continued stay authorization for as many days as deemed medically necessary.
Services must be provided under the direction of a licensed physician in a facility maintained primarily for the treatment and care of patients. The facility must be an institution that is either: (a) licensed or formally approved as an acute care hospital by the officially designated authority in the state where it is located; (b) except as otherwise permitted by federal law, meet Medicare participation requirements as a hospital and maintain a utilization review plan meeting 42 CFR 482.30; or (c) provide acute care psychiatric hospital services as defined in this manual for members. These provider and facility requirements apply to acute inpatient hospital services covered under this policy.
Acute inpatient admission is not medically necessary when the member is not dangerous to self or others and the presenting risk can be managed appropriately at a less restrictive level of care. The admission criteria require, as the primary diagnosis, any mental health diagnosis from the current DSM or ICD and that the member demonstrate danger to self or others with acuity that cannot be safely treated outside the inpatient setting. If these conditions are not met, consider outpatient, intensive outpatient, partial hospitalization, or other community-based alternatives that are less restrictive.
Definition: Inpatient Level of Care
inv-11: Inpatient — criteria group
Admission criteria: primary DSM/ICD diagnosis and danger to self/others not manageable at lower level of care. Continued stay criteria: active treatment, inadequacy of lower level of care, and likelihood of benefit or high risk of deterioration without inpatient care.
Provider Requirements, Prior Authorization, and Documentation
Prior authorization rules for in-state vs OOS placements
Prior authorization is not required for in-state acute inpatient hospital stays; prior authorization is required for out-of-state (OOS) facilities and may be submitted via AutoAuthorization. The department or the Utilization Review (UR) Contractor may issue prior authorization for as many days as deemed medically necessary, up to 60 days.
Prior authorization required for out-of-state placements
Obtain prior authorization when placing a member in an out-of-state (OOS) acute inpatient facility; failure to obtain required OOS prior authorization may result in denial of payment.
Required documentation and Certificate of Need (ages 18–21)
Document in the member's file that the member meets the medical necessity criteria for acute inpatient admission. For members age 18–21, include a Montana Medicaid Adult Certificate of Need; for emergency admissions the certificate must be completed by the team responsible for the plan of care within 14 days after admission.
- Document that the member meets medical necessity criteria (admission/continued stay requirements).
- For ages 18–21, include Montana Medicaid Adult Certificate of Need per 42 CFR 441.152 and 441.153.
- For emergency admissions (ages 18–21), complete the certificate within 14 days of admission.
Prior authorization procedures and limits for out-of-state (OOS) facilities
Submit prior authorization for any out-of-state acute inpatient admission (may be submitted via AutoAuthorization). The department or UR Contractor may authorize continued stay for as many days as medically necessary, up to 60 days.
- Use AutoAuthorization (Policy 206/206a) option when applicable.
- Anticipate that OOS authorizations may be issued up to 60 days based on medical necessity.
Available Services and Case Management
inv-12: Targeted Case Management
Service Definitions
Background and Purpose
Acute inpatient hospital services cover members who require inpatient treatment under physician direction for conditions other than tuberculosis or nonpsychiatric medical illnesses. Admission focuses on stabilization when a member poses danger to self or others and cannot be treated safely at a lower level of care. The typical scope includes diagnosis and active treatment of mental health conditions with the goal of reversing or stabilizing symptoms that meet admission criteria.
For eligibility the policy requires a primary mental health diagnosis from the current DSM/ICD and demonstrable risk that cannot be managed less restrictively; continued inpatient care must provide active treatment and a reasonable likelihood of clinically significant benefit or prevention of acute deterioration.
OpenPayer is powered by Trek Health's payer performance platform. Trek continuously ingests, validates, and normalizes Transparency in Coverage data alongside payer policies and other commercial payer data to create a structured payer intelligence foundation. OpenPayer uses this foundation to deliver personalized search results, dynamically generated policy pages, and tailored policy monitoring based on each user's payers, specialties, billing codes, and areas of interest. The same intelligence powers broader payer performance workflows, including reimbursement benchmarking, contract evaluation, payer negotiations, and financial decision-making.