Anesthesia Auto-Coding

HANK CODES reads the whole anesthesia encounter. It reads the anesthesia record, the surgeon procedure note, procedure notes for lines and blocks, and the facesheet. It identifies the surgical procedure, selects the anesthesia (ASA) code, extracts case times, and builds the claim with modifiers and diagnoses.

How the autocoder picks the ASA code

First the autocoder identifies the surgical procedure from the documentation. It then assembles the anesthesia codes that map to that procedure. Every mapped code is an equally valid option.

The selection rule has two steps:

1. Keep only the codes the documentation supports.
2. Among those codes, pick the one with the highest base units.

The autocoder never prefers one mapped code because it is listed first. If two supported codes tie on base units, the autocoder picks the more anatomically specific code.

Documented, not booked

The autocoder codes what the documentation supports. It does not code the booked or scheduled procedure.

Printed words are evidence wherever they appear, and booking text counts as words. A printed CPT code number is not evidence on its own. The autocoder does not expand a printed code number into its official description to find procedure details that nobody documented. So a booked therapeutic endoscopy code does not establish that a therapeutic act happened. The documented words must say so.

Printed anesthesia codes in the 0xxxx range stay trusted.

When the autocoder declines to pick a code

The autocoder is not forced to pick from the mapped list. If no mapped code is supported by the documentation, it returns no primary code and raises an alert instead of guessing.

Two related alerts help you see these cases:

• anes_code_no_procedure_doc_support (FINANCIAL, severity 5). A billed anesthesia code cites only plan or history documentation, although the encounter also contains procedure documentation.
• anes_crosswalk_gap_review (FINANCIAL, severity 6 or 7). A documented procedure has no usable anesthesia mapping, and it may outweigh the procedures that did map.

Anesthesia type comes from documented evidence

The autocoder decides general, MAC, regional, spinal, epidural, or combined spinal-epidural from documented evidence. It ranks the evidence by the note that carries it. A post-operative or intra-operative anesthesia note outranks a pre-operative note, and both outrank an "Anesthesia: MAC" header in the surgeon operative note. Documented airway management overrides everything.

If a case resolves to MAC on the surgeon note alone, the autocoder suppresses the MAC modifier and raises mac_modifier_low_trust (HARDSTOP, severity 7). A coder confirms MAC against general anesthesia. When the anesthesia record itself documents MAC, the modifier stays and no alert fires.

Times and modifiers

The autocoder extracts start and stop times per line item and calculates billable minutes. A line item with no times raises anes_time_no_times (HARDSTOP, severity 10). Flat-fee anesthesia codes skip the time checks.

The autocoder also applies physical status and medical direction modifiers. If the record documents a physical status but no P-modifier reaches the claim, asa_modifier_missing asks a coder to add it.

Your facility configuration controls alert severities and most processing rules. Contact your Hank representative to change them.

For every anesthesia alert, its trigger, and the reviewer action, read Anesthesia Alerts Reference.

How this reaches you

What happens next depends on how your organization consumes HANK CODES. In HANK Claim Maker, a HARDSTOP alert places the claim in the review queue your administrators configured for it. Organizations that consume the coding API directly decide in their own workflow which alerts pause a claim, who reviews them, and when a claim is released.