Catheter flushing in hospitals: when to charge and how to avoid denials

Peripheral venous catheter flushing is a nursing procedure performed several times a day on hospitalized patients. However, it is also one of the most underreported procedures in hospital billing: performed routinely, often without a structured entry in the medical record, it is frequently missing from the forms sent to payers.

The result is twofold: lost revenue for the hospital and exposure to denials when the charge is made without documentation to support it.

This article explains when flushing should be charged, the conditions for payers to accept the charge and how correct documentation protects the institution’s billing.

What peripheral venous catheter flushing is

Flushing, also called saline locking, is the procedure that keeps the peripheral venous catheter clear and working between uses. It consists of infusing a small amount of saline solution (0.9% sodium chloride) through the device, ensuring the line stays patent (unobstructed) for the next administration of medications, solutions or blood products.

The procedure is the exclusive responsibility of the nursing team. It is up to this team, together with the Hospital Infection Control Service (CCIH), to define the indication, technique and frequency of saline flushing according to the institutional protocol in force.

From a clinical standpoint, flushing prevents clots from forming in the catheter, reduces the risk of phlebitis and device-associated infection, and ensures the continuity of intravenous treatment without interruptions caused by line obstruction.

When flushing should be performed

The standard frequency recommended in the literature is every 6 hours for catheters in intermittent use. Beyond this routine, flushing is indicated in three specific situations:

• Before administering medications:to check catheter patency and confirm the line is patent (clear) before starting any infusion.

• After administering medications:to clear the catheter and prevent drug residue from precipitating inside the device, which can cause obstruction or an unwanted drug interaction.

• After blood draws or infusion of blood products:blood and blood components increase the risk of clotting in the catheter. Saline flushing immediately after these procedures is essential to keep the line clear.

In adult patients, these three situations, added to the every-6-hours routine, determine the actual frequency of flushes over a hospital stay. In patients with long-term catheters or on continuous vesicant medications, the frequency may be higher, according to institutional protocol.

How to perform flushing: technique and materials

The technique described below is widely used in care practice. Each institution should adapt the procedure to its internal protocol validated by the CCIH.

Materials needed

• Kidney dish.

• Ampoule of 0.9% sodium chloride.

• 10 ml syringe.

• 40 x 12 needle.

• Two alcohol swabs.

• Pair of procedure gloves.

Step by step

1. Perform hand hygiene before gathering the materials.

2. Disinfect the sodium chloride ampoule.

3. Draw up the contents of the ampoule with a 10 mL syringe and 40 x 12 needle.

4. Put on the procedure gloves.

5. Disinfect both ports of the Y-connector (Polifix) with an alcohol swab.

6. Test catheter patency with approximately 2 ml of saline solution, keeping the syringe connected to the IV line port.

7. Administer the medication through the other port of the connector, if any.

8. Flush both ports of the connector with about 2 mL of saline solution, regardless of the amount of medication administered.

9. Organize and dispose of the materials in the appropriate place.

10. Perform hand hygiene.

11. Check off the procedure on the prescription and record it in the nursing progress notes.

Step 11 is the most critical from a billing standpoint. Without the check-off on the prescription and the entry in the medical record, the procedure performed has no documentary support for billing.

How to charge for flushing in hospital billing

Charging for flushing depends on the type of contract between the hospital and the payer. Broadly speaking, there are two scenarios:

When it is included in the daily rate:many contracts provide that routine nursing procedures, including catheter saline flushing, are part of the admission package. In this case, the procedure does not generate a separate charge, but it must be recorded for care audit purposes.

When it is charged per event:in contracts that pay for nursing procedures separately, flushing can be charged for each documented occurrence. In this case, the reference code to use must be checked against the price table agreed with the payer, usually linked to the inpatient nursing procedures listed in TUSS.

What both scenarios have in common is documentation. Without clear documentation in the medical record indicating the time, the port and who performed it, the payer has grounds to deny the charge or question care compliance.

Before billing flushing per event, the billing manager must check the contract with each payer to confirm whether the procedure is covered and which code should be used. Skipping this check is one of the main causes of technical denials for this type of charge.

Correct documentation: what must be in the medical record

The flushing record must contain, at a minimum: date and time performed, port used (which of the connector’s ports), solution used (volume and concentration of the sodium chloride), identification of the professional who performed the procedure and the check-off on the medical prescription.

Generic entries such as “catheter patent” or “saline flush performed” without the data above are not enough to support the charge in an audit. The payer may interpret the note as incomplete and deny the item.

Beyond completeness, traceability is essential. Records in an electronic system with a timestamp and identification of the professional carry far more weight in a denial appeal than unstandardized handwritten notes on paper.

Standardizing the record, established in the institutional protocol and reinforced in periodic training for the nursing team, is the main mechanism of billing protection for this procedure.

How Rivio protects hospital revenue

Flushing is a clear example of a procedure that generates invisible losses: performed frequently, rarely charged rigorously and almost never audited in real time. During a five-day hospital stay, a patient may receive dozens of flushes, many of them without a traceable record.

Rivio automatically audits nursing records by cross-checking the progress notes in the medical record against the items billed. When something was performed but not charged, or charged but not recorded, the system flags the inconsistency before the form is sent to the payer. The result is fewer denials, fewer appeals and more revenue actually received.

FAQ - frequently asked questions about catheter flushing

Can flushing be charged under every contract with payers?

It depends on the contract. In some, the procedure is included in the nursing daily rate. In others, it is paid per event. The billing manager must check each payer’s contract before charging separately.

Which code should be used to charge for flushing?

The code varies according to the agreed price table. In general, the procedure falls under the inpatient nursing procedure codes listed in TUSS. The check should be based on the contract in force with each payer.

What happens if flushing is charged without an entry in the medical record?

The payer may deny the item for lack of documentation proving it was performed. Incomplete records, without the time, identification of the professional or the check-off on the prescription, do not support the charge in an audit.

Is the 6-hour frequency mandatory, or can it vary?

The 6-hour frequency is the recommended standard for catheters in intermittent use, but each institution should define the frequency based on its internal protocol validated by the CCIH. In specific situations, such as the use of blood products or vesicant medications, saline flushing may be more frequent.