Two lumens at one vascular site

Read an original fictional chart, identify the supported facts, and explain your coding workflow.

Chart gym · Original fictional record

Service date: 2026-09-09 · Outpatient professional or facility service as stated; Medicare relationship

Use your code books and write your reasoning before opening the walkthrough. This exercise contains no real patient information.

Encounter

Fictional adult attends one outpatient infusion encounter for ordered treatment. The access record documents one catheter entering a single vascular site. The catheter has two lumens. No second vascular puncture or separate access site is used during the encounter.

Administration

Two different ordered substances are administered through the separate lumens. Each has its own medication administration record, dose and timing. The case does not ask for the final administration codes because the exact drugs and complete timing intervals are not supplied.

Claim proposal

The draft contains two initial infusion services, one for each lumen. The proposed justification is that two substances and two lumen labels appear in the record. No separately necessary second site or independently necessary return encounter is documented.

Review scope

Determine whether the documented access facts establish the separate-site exception. Then explain what additional information would be needed to select initial, subsequent or concurrent entries for the actual administrations. Do not infer two sites from two medication records.

Your coding worksheet

Count vascular access sites.
Distinguish lumens from sites.
Evaluate the two-initial-service proposal.
List the missing facts for final administration selection.

In your notebook, record the supported facts, your index route, the instructions you checked, and any missing detail that limits your answer.

Compare with the worked explanation

There is one vascular access site.
Both lumens belong to the same catheter entering that site.
NCCI B.3 does not support two initial services merely because both lumens are used.
Final entries require the actual substances, setting, purpose, timing and complete administration instructions.

Reference sections: B.2–3

Practice the linked chart questions