Common Under-Documented Procedures

Pamela Linton, CPC, CANPC
Corporate Coding Manager – Anesthesia and Pain Management

With reimbursement pressures continuing to grow, ensuring that anesthesia practices collect every dollar they are entitled has never been more important. Fortunately, this task is made easier if providers take steps to reduce or eliminate common documentation and coding mistakes.

Reducing errors requires a detailed, up-to-date understanding of anesthesia coding, a working knowledge of anatomy, and open channels of communication between coders and physicians. A process that allows coders to follow-up with physicians on specific case questions and also offers real-time feedback regarding incomplete or inaccurate documentation can go a long way toward strengthening the anesthesia revenue cycle.

Many of the most common CPT under-coding errors affecting anesthesia reimbursement result from a lack of detail and clarity about the nature and location of the underlying surgical procedure. Here are some primary examples:

New For 2019:
Laparoscopic Hernia Repair (includes ventral, umbilical, spigelian, epigastric and incisional hernias)

2018 Crosswalk:

  • Laparoscopic epigastric, spigelian and umbilical hernia repairs crossed to 00750 with 4 base units
  • Laparoscopic ventral and incisional hernia repairs
    • Non-incarcerated hernias crossed to either 00752 or 00832 both with 6 base units
    • Incarcerated hernias crossed to 00752 with 6 Base units

2019 Crosswalk:

  • Laparoscopic epigastric, spigelian, umbilical, ventral and incisional hernia repairs now cross to either 00790 with 7 base units for upper abdominal procedures or 00840 with 6 base units for lower abdominal procedures.

***Documentation of upper abdomen, when applicable, will be the only way coders will know to assign the higher base units***

Anterior/Posterior Spinal Procedures (laminectomy and fusion procedures)

  • Anatomical location – procedures on the lumbar spine have 8 base units (00630 )while procedures on the cervical (00600) and thoracic spine (00620) have 10 base units
  • Number of Levels – multi-level procedures qualify for 13 base units (00670)
  • Instrumentation – will also qualify for 13 base units (00670)

Special Note: A multi-level procedure is defined as one that crosses over three vertebral bodies and the associated interspaces (i.e., a laminectomy performed at L2/L3 and L3/L4 would be considered a multi-level a procedure). Single level procedure done bilaterally would not be considered a multi-level procedure.

Open Abdominal Procedures

  • Location – Upper abdominal procedures have 7 base units (00790) while lower abdominal procedures have six base units (00840). The dividing landmark is the umbilicus.

Cardiac Bypass and Valve Replacement/Repair Surgery

  • On pump or off pump – On pump CABG procedures have 18 base units (00567). Off pump procedures for a CABG have 25 units (00566).

Exception to the rule – A CABG procedure done more than 30 days from the original bypass procedure (there is no time limit on how far back you can go) qualifies for 20 base units (00562).

Additional information: On pump procedures include hypotension and/or hypothermia codes. However, off pump procedures do not. Documentation of these add-on codes could result in additional revenue from most private payers. These two add-on codes are valued at 5 units.

Interstitial Radioelement Application or biopsy – Prostate

  • Is the procedure done with transrectal ultrasound? If not, the procedure has three base units (00400 or 00910). If yes, the procedure has five base units (00902)

Exception to the rule: Saturation biopsies (CPT code 55706) crosses to 00400 (3 base units).

Thoracoscopy/Thoracotomy Procedures

  • One lung ventilation – Documentation of one lung ventilation adds 3 base units to your thoracotomy/thoracoscopy procedure. Documentation of intubation with a double lumen endotracheal tube or an exchange of a single lumen tube to a double lumen tube AND documentation of one lung ventilation are both required. One lung ventilation could be documented as OLV somewhere in the remarks or on the anesthesia graph or as a notation as lung ↓ and lung ↑ somewhere on the anesthesia record. Documentation of a double lumen tube alone is not sufficient documentation for one lung ventilation. Incomplete documentation should result in a request for additional information.
  • Diagnostic VATS (Video Assisted Thoracoscopy Surgery) vs. Surgical VATS – A diagnostic procedure will have 8 (00528) or 11 base units (00529) where a surgical procedure will have 12 (00540) or 15 base units (00541). Reminder: 00529 and 00541 require documentation of one lung ventilation.

Open Epigastric Hernia Repair

  • Is the hernia incarcerated and does that incarceration involve the intestines? If so, the procedure goes from 4 base units (00750) to 7 base units (00790).


  • A regular hysterectomy has 6 base units (00840 or 00944), but a radical hysterectomy that includes a bilateral pelvic lymphadenectomy and para-aortic lymph node sampling biopsy has 8 base units (00846).

Hip Replacement vs. a Revision

  • A total hip replacement has 8 base units (01214). However, if the patient has had a prior replacement and the procedure is, in fact, a revision the procedure has 10 base units (01215).

Shoulder Arthroscopy

  • A simple diagnostic shoulder scope has 4 base units (01622). A surgical shoulder arthroscopy has 5 base units (01630).

Knee Arthroscopy

  • The same pattern holds for a knee scope. If diagnostic-only, the scope has 3 base units (01382). But a surgical knee scope has 4 base units (01400).

Simple or Partial Mastectomy

  • A simple or partial mastectomy or lumpectomy has 3 base units (00400). However, if an axillary lymph node biopsy or lymphadenectomy is performed, the procedure has 5 base units (01610).


  • The defibrillator active thresholds are tested (active threshold testing includes the induction of an arrhythmia with sensing and treatment by the ICD/C device), the procedure has 7 base units (00534).
  • The defibrillator active thresholds were not tested, the procedure has 4 base units (00530).


  • For some anatomical locations, the depth of debridement does not change the base units.
    • Debridement of hand
      • Skin and subcutaneous tissue – 3 base units (00400)
      • Muscle – 3 base units (01810)
      • Bone – 3 base units (01830)
  • For others, the difference in base units is surprisingly different.
    • Debridement of upper thigh
      • Skin and subcutaneous tissue – 3 base units (00400)
      • Muscle – 4 base units (01250)
      • Bone – 6 base units (01230)

In today’s environment where every dollar counts, a complete procedure description can go a long way in maximizing your reimbursement. Knowing what information is important is the first step in achieving this common goal. All of the procedures listed above have the potential to increase or decrease your bottom line based on the information provided for coding. Please feel free to reach out to your management team with any questions.

AMA CPT® Professional Edition 2019
ASA 2019 Relative Value Guide
ASA 2019 Crosswalk
Direct Correspondence with the American Society of Anesthesiology

Revision History:
Created – April 2016
Revised – February 2017 – to add the new guidance for Cardio Defibrillators ASA code assignment. Documentation must include defibrillator threshold testing (active threshold testing includes the induction of an arrhythmia with sensing and treatment by the ICD/C device) in order to report the service with 00534 (7 base units). Otherwise the service is reported with 00530 (4 base units)
Reviewed – January 2018 (No Revisions Necessary)
Revised – January 2019 to add the new crosswalk changes for laparoscopic hernia repair codes