CPT
00400 — Anesthesia for procedures on integumentary system, extremities, anterior trunk, perineum, NOS
Anesthesia time = base units + minutes ÷ 15. Verify the math.
Anesthesia
00100 — Anesthesia for procedures on salivary glands, including biopsy
This code covers general anesthesia for procedures on salivary glands in the head area, such as gland biopsies or removal.
- Typical setting: Hospital operating room, ASC
- National avg charge (illustrative): $200–$600 depending on time; base units = 5
- Most-disputed reason: Time padding: billing more anesthesia time units than documented start-to-finish in the anesthesia record
What it means
What 00100 actually means
This code covers general anesthesia for procedures on salivary glands in the head area, such as gland biopsies or removal. Anesthesia is billed using base units plus time units (each time unit = 15 minutes), multiplied by a conversion factor.
Common errors with this code
What goes wrong on real bills.
Most bills that look correct still contain at least one of these issues. Up to 49% of medical bills contain errors (CFPB).
- Time padding: billing more anesthesia time units than documented start-to-finish in the anesthesia record
- Billing anesthesia for a procedure performed under local anesthesia only
- Billing anesthesia for a minor procedure that falls below the threshold requiring separate anesthesia billing
If you see 00100 on your bill
Three steps before paying.
1. Get the itemized bill. If your statement only shows a summary, request the CPT-level itemized bill before paying. Generate the request language →
2. Cross-check against the EOB. Compare what your insurer's Explanation of Benefits says you owe versus what the hospital is asking. They disagree more often than people think. Read the bill-vs-EOB guide →
3. Run a free Bill Scan. Upload the bill (and EOB if you have it) and BillBusted will flag the most likely issues with this specific code in your specific state. Run free scan →
Related codes
Other codes in this category.
People who land on 00100 often also see these adjacent codes on the same bill.
CPT
00567 — Anesthesia for direct coronary artery bypass grafting; with pump oxygenator
Anesthesia time = base units + minutes ÷ 15. Verify the math.
CPT
00731 — Anesthesia for upper GI endoscopic procedure, endoscope to proximal duodenum
Anesthesia time = base units + minutes ÷ 15. Verify the math.
CPT
00811 — Anesthesia for lower intestinal endoscopic procedure, endoscope introduced distal to duodenum
Anesthesia time = base units + minutes ÷ 15. Verify the math.
CPT
01400 — Anesthesia for open or arthroscopic procedures on knee joint
Anesthesia time = base units + minutes ÷ 15. Verify the math.
CPT
01480 — Anesthesia for open procedures on bones of lower leg, ankle, and foot
Anesthesia time = base units + minutes ÷ 15. Verify the math.
Related BillBusted guides
Plain-English reads if you see 00100 on a bill.
00100 FAQ
Plain-English answers.
What does 00100 usually cost?
$200–$600 depending on time; base units = 5. Costs vary by region, payer contract, and whether the service was performed in a hospital outpatient department (which adds a facility fee) versus a free-standing clinic.
What's the most common billing error on 00100?
Time padding: billing more anesthesia time units than documented start-to-finish in the anesthesia record
What should I do if I see 00100 on my bill?
Request the itemized bill and the matching EOB from your insurer. Compare the units/quantity billed against what you actually received. Run a free BillBusted scan to flag the most likely errors specific to 00100 before paying.
Don't pay 00100 blindly.
The free scan tells you in under 60 seconds whether this charge looks reasonable for your situation.