High-cost hospital claims: how to submit them without errors

High-cost hospital claims concentrate the largest billable amounts and the greatest risks of denial. A surgery with OPME (implants and special materials), a prolonged ICU stay or a chemotherapy cycle bring together, in a single bill, dozens of items with different documentation requirements, per-procedure authorizations and specific traceability rules. An error at any of these points can compromise a claim of significant value before it even reaches the payer’s auditor.

The process of building and submitting these claims does not tolerate the same room for improvisation as less complex claims. That is why it is essential to know what needs to be ready before starting, how to organize each category of item and what to review before submission.

What makes a claim high‑cost

In hospital billing, the term “high cost” describes claims that combine a high unit value per item with a high density of billable items. There is no minimum amount that places a claim in this category: what defines it is the complexity of the building process and the financial impact of each error.

In practice, four profiles account for most of these claims:

• ICU stays, with daily accumulation of daily rates, fees, continuous medications and bedside procedures;

• major surgeries using OPME, in which the value of the materials often exceeds that of the physician fees;

• cancer treatments with chemotherapy or immunotherapy, in which claims can exceed R$ 2 million in drugs alone;

• highly complex procedures such as transplants and cardiovascular surgeries, with multiple professionals and long hospital stays.

What these profiles have in common is that each billable item has its own documentation chain: authorization, record in the medical record, coding in the correct table and, in some cases, physical traceability of the material. Failures at any link in this chain result in a denial, and the financial impact is proportional to the item’s value.

Before building the claim: what needs to be ready

Building a high-cost claim starts before the billing specialist opens the system. Three elements need to be available and verified before any entry is posted.

1. Prior authorization that is valid and within scope.

For each procedure, material or drug that requires authorization, it is necessary to confirm that the authorization was issued, is still valid and covers exactly what was performed. Additional procedures performed during the hospital stay, dose adjustments in chemotherapy or OPME substitutions need their own authorization. An original authorization does not cover variations that were not communicated to the payer.

2. Complete and closed medical record

The medical record is the claim’s source of truth: everything that can be billed must be recorded in it. Physician progress notes, prescriptions, medication administration records, surgical descriptions and test reports need to be complete and consistent with one another before billing begins. Starting to build the claim with an incomplete medical record is the path to denials.

3. OPME traceability, when applicable

The Ministry of Health’s Manual of Good Practices for OPME Management requires every implantable material to come with traceability labels, with one copy in the medical record, one in the tax documentation and one in the patient’s document. Without this traceability formalized before billing, the material has no documentary basis to be charged.

How to build the claim by item category

Each category of item in a high-cost claim has specific coding, documentation and checking rules. Treating them all the same way is one of the most common causes of billing errors.

Procedures and physician fees

Each procedure must be coded in the TUSS table with the correct code for what was actually performed, including qualifiers for access route, surgical technique and tier.

In surgeries with multiple procedures, the CBHPM percentage reduction rules apply and must be calculated correctly before posting.

Fees for the surgical team, including the anesthesiologist, assistants and scrub technician, must be recorded with each professional’s CRM (Regional Medical Council) number and be consistent with the tiers posted. A missing team member or a mismatch between the surgical tier and the fee charged are frequent causes of technical denials in surgical claims.

OPME and special materials

For each OPME item used, the claim must contain:

• the material’s code according to the table contracted with the payer;

• the exact quantity used;

• the invoice linked to the material;

• the surgical description confirming its use and the traceability label in the medical record.

The charge must match exactly the material authorized by the payer. Any substitution of material during surgery, even by a clinical equivalent, requires a record of communication to the payer and, when possible, authorization for the new material before billing.

High-cost drugs

Immunobiologics, chemotherapy drugs and other restricted-use medications require a prior authorization that is valid at the time of administration, a medical prescription with dosage and treatment regimen, an administration record in the medical record and coding consistent with the authorized presentation.

The dosage charged must match exactly what was administered, with a record of each application. Charges for doses without an administration record made at the time of care are frequently denied and rarely reversed on appeal.

Daily rates, fees and medical gases

The type of daily rate charged must match the level of care recorded in the medical record for each day of the hospital stay. Changes in level of care, such as a transfer from the ward to the ICU or from the adult ICU to a step-down unit, must be documented with date and time.

Fees for the operating room, post-anesthesia recovery and special procedures must have a record of completion in the medical record.

For medical gases, the volume charged must be consistent with the prescription and the administration record of each shift, with special attention to duplicates at shift changes.

Pre-submission review: what to check

The pre-submission review is the last chance to correct inconsistencies before they become denials. For high-cost claims, this step must be systematic, covering at least five points.

The first is consistency between the ICD code and the procedures charged. The diagnosis recorded in the medical record must clinically support each procedure, material and drug posted to the claim.

The second is compliance with the authorization. Each item that requires prior authorization must be checked against the scope of the authorization issued.

The third is OPME traceability. For each implantable material in the claim, check whether the traceability label is in the medical record, whether the invoice is linked and whether the surgical description confirms its use. The absence of any of these elements is direct grounds for denying the material.

The fourth is validation of the TISS file. The XML file must pass the system’s own validation before submission, with all required fields filled in and no structural errors.

The fifth is the contractual deadline. Each payer has a deadline for receiving claims after the patient’s discharge. For high-cost claims, where building and reviewing take longer, the risk of missing this deadline is greater. The deadline must be visible to the team from the moment the claim is closed.

Prospective audit is the process that formalizes this review, ensuring systematic coverage of all items before submission, with defined responsibilities and a record of each check performed.

The most common errors when submitting high‑cost claims

Beyond building errors, submission itself involves a set of recurring operational failures that compromise technically well‑built claims.

Authorization expired at the time of submission

One of the most frequent errors. In long hospital stays, authorizations issued at admission can expire before the claim is closed. The hospital performs the procedures within the authorization period but submits the claim after it expires. The payer denies it on formal grounds, regardless of whether the authorization was valid during care.

TISS batch with a required field missing or filled in incorrectly

The wrong payer code, a plan member card number with a mismatched digit or a date of service outside the authorized period result in automatic rejection of the batch before any review on the merits. These errors can be avoided by validating the file before submission, but they often go unnoticed in teams with a high volume of claims.

Submission to the wrong payer code

Hospitals that work with multiple products from the same insurer need to use the specific code for each one. Submissions to the wrong code result in rejection or in incorrect processing that can take weeks to identify.

Contractual deadline missed due to a backlog of pending issues

High-cost claims have a longer closing cycle because they depend on more documents, more authorizations and more checks. When the team does not monitor the deadline from the start, the backlog of pending issues at the end of the process leads to late submission, with total loss of the right to charge for that claim.

A well-built claim is protected revenue

In high-cost claims, the quality of the billing process has a direct financial impact proportional to the claim’s value. A R$ 500 thousand claim submitted with an authorization error or after the deadline is not a claim with a problem: it is lost revenue. The effort of disputing it rarely recovers what could have been avoided with a rigorous building and review process.

In 2024, Brazilian private hospitals had R$ 5.8 billion in payments withheld by health plans through denials. A significant part of this amount is concentrated in high-cost claims, where each individual denial has a greater impact on the hospital’s results.

Rivio audits 100% of hospital claims before they are submitted to the payer, automatically checking coding, OPME traceability, compliance with authorizations and TISS validation, with oversight from billing specialists at every stage of the process.

Frequently asked questions about billing high‑cost claims

What is a high-cost hospital claim?

A high-cost claim is one that combines a high unit value per item with a high density of billable items, each with its own documentation requirements. The most common profiles are ICU stays, surgeries with OPME, cancer treatments and highly complex procedures such as transplants and cardiovascular surgeries.

What are the main errors in billing high‑cost claims?

The most frequent errors are: authorization expired at the time of submission, a TISS batch with a required field missing or incorrect, submission to the wrong payer code, a contractual deadline missed due to a backlog of pending issues and a mismatch between the ICD code and the procedures charged. Most can be avoided with a systematic review process before submission.

What needs to be documented before building a high‑cost claim?

Three elements need to be ready before billing begins: a prior authorization that is valid and within scope for each procedure that requires one, a complete and closed medical record with all care records, and formalized OPME traceability when there is implantable material. Starting to build the claim without these elements means starting with gaps that will become denials.

How can denials be avoided in ICU and oncology claims?

Prevention starts before billing: strict control of authorizations during the hospital stay, recording of all administered items at the time of care and immediate communication to the payer about changes in level of care or protocol. When building the claim, each category of item must be checked against specific criteria. The pre-submission review must cover ICD-procedure consistency, compliance with the authorization, OPME traceability, TISS validation and the contractual deadline.