Chapter 14: Anesthesia Notes
Anesthesia
Introduction
Anesthesia codes are grouped anatomically, starting with the head.
Many codes are "not otherwise specified" to cover cases without a specific code.
Example: Code 00920 for male genitalia procedures, including open urethral procedures.
Selecting anesthesia codes is similar to assigning procedure codes.
Check the CPT® Index under "Anesthesia" or the Anesthesia section (00100-01999).
New coders should use the Anesthesia section to learn the codes.
Codes aren't always under the surgical description (e.g., mastectomy under "breast").
Liver harvesting (code 01990) is under "Other procedures."
Anesthesia crosswalk books link surgical codes to anesthesia codes.
If multiple codes are suggested, choose the most applicable.
Types of Anesthesia
Three primary types:
General Anesthesia: Affects the brain, causing unconsciousness.
Regional Anesthesia: Loss of nerve sensation in a body region via anesthetic injection.
Spinal anesthesia: Injected beneath the spinal cord membrane (subarachnoid/intrathecal).
Epidural anesthesia: Injected into the epidural space.
Nerve block: Injected around nerves near the operative field.
Monitored Anesthesia Care (MAC): Light or no sedation during surgery with local anesthesia.
Patient responds to stimulation and maintains their airway.
Anesthesia provider is ready to convert to general anesthesia if needed.
Local anesthesia is part of the surgical package and not reported separately.
Anesthesia Providers
Anesthesiologist: Physician with anesthesiology program completion.
Can perform, medically direct, or supervise anesthesia care team members.
Certified Registered Nurse Anesthetist (CRNA): APRN with nurse anesthetist training.
May be medically directed or non-medically directed.
Anesthesiologist Assistant (CAA): Healthcare professional with premedical background and master's degree.
Must be medically directed by an anesthesiologist.
Anesthesia Resident: Physician in anesthesiology residency.
Student Registered Nurse Anesthetist (SRNA): APRN in nurse anesthetist training.
Anesthesia Coding Terminology
One-Lung Ventilation (OLV): One lung ventilated, the other collapsed for surgical access in the thoracic cavity.
Pump Oxygenator: Cardiopulmonary bypass (CPB) machine used as heart and lungs during surgery.
Intraperitoneal: Within the peritoneal cavity. Upper abdomen organs: stomach, liver, gallbladder, spleen, jejunum, ascending/transverse colon. Lower abdomen: appendix, cecum, ileum, sigmoid colon.
Extraperitoneal/Retroperitoneal: Outside/behind the peritoneum. Lower abdomen: ureter, bladder. Upper abdomen: kidneys, adrenals, lower esophagus. Also: aorta, inferior vena cava.
Radical: Extensive surgery for severe health threats like cancer.
Diagnostic or Surgical Arthroscopic Procedures: Procedures on joints. Assign diagnostic code only if no surgery is performed. Assign surgical code if a surgical procedure like meniscectomy is performed.
Postoperative Pain Management
Surgeon can request postoperative pain management, billed separately if anesthesia isn't dependent on the regional anesthetic technique.
Nerve block codes (e.g., 64415) are reported with general anesthesia if placed solely for postoperative pain management.
Nerve block codes are not separately reported if the block is the anesthesia for the procedure.
Example: Carpal tunnel procedure with axillary block uses anesthesia section code (01810 + time), no separate block code.
Coding depends on medication, injection site, and single/continuous block.
CPT code appended with modifier 59 for distinct procedural services.
Ultrasound/fluoroscopic guidance reported separately with modifier 26, unless included in the code.
Codes 64415-64417 and 64445-64448 include imaging guidance, when performed.
Acute pain diagnosis codes in ICD-10-CM category G89.
Continuous catheter codes (e.g., 64448) are for continuous anesthesia administration for postoperative pain management.
If infusion catheter is placed for operative anesthesia, use anesthesia code plus time.
Code 01996 for daily hospital management of epidural/subarachnoid continuous drug administration.
Not reported with femoral/sciatic nerve catheters (e.g., 64448, 64446).
Anesthesiologists report E/M service for re-evaluating postoperative pain if documentation supports the level of service.
Continuous infusion in cervical/thoracic area is reported as 62324.
When epidural/subarachnoid catheter placed for labor, injection codes typically not reported. Use codes under "Anesthesia for Obstetrics." The CPT codes to describe labor epidural/subarachnoid services are listed under the Anesthesia for Obstetrics subsection.
Daily management (01996) cannot be reported on the day of catheter placement, only starting the first postoperative day.
ICD-10-CM Coding
Postoperative diagnosis is coded because the preoperative diagnosis may change intra-operatively.
Supporting diagnosis codes are reported if relevant to either substantiate medical necessity or support physical status modifiers.
Follow standard coding guidelines:
Identify reason for anesthesia service.
Review for supporting diagnosis codes.
Check the Index to Diseases and Injuries and then check the code in the Tabular List
Locate main entry term.
Pay attention to notes in main terms.
Understand coding conventions.
Look for additional instructions in the Tabular List.
Code to the highest level of specificity.
Assign pertinent related ICD-10-CM codes.
CPT Coding
Services included in the base unit value:
Preoperative and postoperative visits.
Anesthesia care during the procedure.
Administration of fluids/blood products.
Non-invasive monitoring (ECG, temperature, blood pressure, pulse oximetry, capnography, mass spectrometry).
Unusual monitoring (arterial lines, central venous catheters, pulmonary artery catheters) are not included.
Base unit values are not in CPT®; ASA determines them based on procedure difficulty and Medicare also publishes a list.
Determining Anesthesia Charges
Base value is the first step.
Time reporting is the second step.
Anesthesia time: Begins when anesthesiologist starts preparing the patient in the operating room or equivalent area; ends when the anesthesiologist is no longer in personal attendance and the patient is safely placed under postoperative supervision. Pre-anesthesia assessment is not included.
Time doesn't need to be continuous.
Example: Axillary block in holding room, then more time in the operating room.
Time reporting varies; no national guideline.
Time units added to base unit value based on local custom.
Medicare requires exact time reporting, not rounded, reported in 15 minutes increments.
Medicare Calculation Example
Anesthesia starts at 11:02, ends at 11:59 (57 minutes).
57 minutes / 15-minute increments = units.
If base value is 6 units, total units = units.
Multiply by Anesthesia Conversion Factor for the area.
Other Insurances
May process time in different increments (exact, 10, 12, 15 minutes).
Multiple Procedures
Report the surgery representing the most complex procedure (highest base unit value).
Report total anesthesia time.
The diagnosis code related to the higher based valued procedure is reported in thr primary position. Reporting additional diagnoses may explain why the reported time is longer that normally expected.
The surgical time does not play a role in determining anesthesia time.
Example
Inguinal hernia repair (00830, base 4) and ventral hernia repair (00832, base 6).
Report ventral herniorrhaphy (00832) because it has a higher base value.
Report total time for both procedures.
Report diagnosis code for the ventral hernia in the primary position.
Reporting the inguinal hernia diagnosis as secondary helps explain why reported anesthesia time is longer than normally expected.
Add-on Codes
Only one anesthesia code is reported unless there is an anesthesia add-on code (e.g., Burn Excision/Debridement, Obstetric).
Add-on codes must be reported with a primary anesthesia code.
Example: +01953 for burn excision/debridement exceeding 9% TBSA, reported with 01952.
Example: 40% TBSA
01952 + Time units (first 4-9% of TBSA)
+01953 x 4 (remaining 31% in 9% increments, with the 4% considered a "part thereof")
01952 is reported with time units; +01953 is reported in units only.
Physical Status Modifiers
Describe the patient's physical status.
Not recognized by Medicare for extra payment, but non-Medicare payers typically pay additional base units.
P1: Normal healthy patient (no extra value).
P2: Mild systemic disease (no extra value).
P3: Severe systemic disease (1 extra unit).
P4: Severe systemic disease that is a constant threat to life (2 extra units).
P5: Moribund patient not expected to survive without the operation (3 extra units).
P6: Declared brain-dead patient for organ donation (no extra value).
Example: Non-Medicare patient with severe systemic disease undergoing CABG with pump oxygenator: 00567-P4.
Qualifying Circumstances
Anesthesia add-on codes for difficult circumstances.
ASA assigns base unit values (not in CPT®).
Not recognized by Medicare for additional payment.
+99100: Extreme age (younger than 1 year or older than 70) - 1 extra unit.
+99116: Total body hypothermia - 5 extra units.
+99135: Controlled hypotension - 5 extra units.
+99140: Emergency conditions - 2 extra units.
Documentation must support the code.
Emergency: Delay in treatment would significantly increase threat to life or body parts.
Highlight parenthetical notes about qualifying circumstance codes.
Example: Do not report 00326 with 99100.
Anesthesia calculation for non-Medicare payers: BASE + TIME + PHYSICAL STATUS MODIFIERS + QUALIFYING CIRCUMSTANCES, all multiplied by the CONVERSION FACTOR.
Medicare calculation: BASE + TIME multiplied by the MEDICARE CONVERSION FACTOR for the region.
Additional Items Billable
Invasive monitoring devices placed by anesthesia provider are coded separately.
If another provider places the line/catheter, the anesthesia provider doesn't report it.
Time is not reported separately for flat-fee procedures and the codes are found in the surgery section of the CPT® book.
Common codes reported in addition to anesthesia:
31500: Emergency endotracheal intubation (when not undergoing anesthesia; intubation during anesthesia is included).
36620: Arterial catheterization for sampling, monitoring, or transfusion.
36555/36556: Non-tunneled central venous catheter insertion (age-related).
93503: Flow-directed catheter (e.g., Swan-Ganz) insertion for monitoring.
Look for documentation of PAC or SG placement in the anesthesia record or procedure notes.
Moderate Sedation
Can be provided by a physician other than the surgeon or by an anesthesiologist.
Provided without an anesthesia machine and backup for general anesthesia.
Does not include minimal sedation, deep sedation, or monitored anesthesia care.
Coders are directed to the Anesthesia section of CPT® to report services. Only anesthesia providers report anesthesia codes.
Monitored Anesthesia Care (MAC)
Involves sedatives, analgesics, hypnotics, anesthetic agents as needed.
Patient remains arousable and maintains an open airway.
Anesthesia plan is case-by-case.
Anesthesia provider must be qualified and ready to convert to general anesthesia if needed.
If the patient loses consciousness and the ability to respond purposely, the anesthesia care is a general anesthetic.
MAC services are paid like general/regional anesthesia.
Insurances request special modifiers to identify MAC.
CPT® Modifiers
23: Unusual anesthesia - procedure usually doesn't need anesthesia but is done under general anesthesia due to unusual circumstances (e.g., pediatric patient).
47: Anesthesia by surgeon - surgeon provides regional/general anesthesia (anesthesia providers don't report).
53: Discontinued procedure - procedure started but stopped due to extenuating circumstances. Check with payer. Most payers may not required for anesthesia CPT® codes. Report the anesthesia code and the time for the discontinued procedure after the start of anesthesia.
59: Distinct procedural service - service is distinct/independent. Used on post-operative pain management to show it's separate from surgery anesthesia.
Direction, Supervision, and Monitoring
Medical direction: Anesthesiologist involved in two, three, or four anesthesia procedures concurrently or one procedure with a qualified anesthesia resident, CRNA, or anesthesiologist assistant.
CMS requirements for medical direction:
Pre-anesthetic exam and evaluation.
Prescribe anesthesia plan.
Personally participate in the most demanding procedures, including induction and emergence.
Ensure procedures not performed by the anesthesiologist are done by a qualified anesthetist.
Monitor anesthesia administration frequently.
Remain physically present and available for emergencies.
Provide indicated post-anesthesia care.
If one or more of above services is not performed, it is not considered medical direction.
While medically directing, anesthesiologists shouldn't provide services to other patients except for:
Short-duration emergencies in the immediate area
Epidural/caudal anesthetic for labor pain
Periodic monitoring of obstetrical patient
Receiving patients for the next surgery
Checking/discharging patients from PACU
Coordinating scheduling
Medical supervision: Anesthesiologist involved in five or more concurrent procedures or doesn't meet medical direction criteria.
Non-medically directed CRNAs: Work without medical direction.
MAC includes monitoring vital signs anticipating the need for general anesthesia or adverse physiological reaction.
MAC Performance:
Pre-anesthetic examination and evaluation.
Prescription of anesthesia care.
Completion of an anesthesia record.
Administration of necessary medication.
Providing postoperative anesthesia care
The anesthesiologist, CRNA, or a qualified individual under the medical direction of an anesthesiologist, must be continuously present to monitor the patient and provide anesthesia care.
Report medical direction modifiers from HCPCS Level II.
HCPCS Level II Modifiers
Anesthesiologist modifiers:
AA: Anesthesia personally performed by anesthesiologist.
AD: Medical supervision by a physician: More than four concurrent anesthesia procedures.
QK: Medical direction of two, three, or four concurrent procedures involving qualified individuals.
QY: Medical direction of one CRNA by an anesthesiologist.
GC: Service performed by a resident under a teaching physician.
CRNA/Anesthesiologist Assistant modifiers:
QX: CRNA service with medical direction.
QZ: CRNA service without medical direction.
The state scope of practice may prohibit an anesthesiologist assistant (AA) from reporting claims with a non-medical direction modifier. If a provider moves from QK Medical direction of 2, 3, or 4 concurrent anesthesia procedures involving qualified individuals to AD Medical supervision by a physician: more than four concurrent anesthesia procedures, the CRNA still I reports QX as the CRNA would not necessarily know the number of cases the anesthesiologist is overseeing.
Medical direction modifiers in the first position.
Additional anesthesia-related modifiers in the second position are informational/statistical.
Modifiers affecting payment are before informational modifiers.
Physical status modifiers are in the second or third position, as applicable.
Examples
00910-AA-P3: Personally performed physician service with a physical status 3 patient.
00142-QK-QS-P3 and 00142-QX-QS-P3: Medically directing physician and CRNA service with a physical status 3 patient under monitored anesthesia care.
MAC Modifiers
CMS and insurers may require:
QS: Monitored anesthesia care service.
G8: MAC for deep, complex, complicated, or markedly invasive surgical procedure.
G9: MAC for patient with a history of severe cardiopulmonary disease.
Reporting G8 or G9 negates the need to report QS separately.
Most anesthesia modifiers are only with anesthesia codes.
Anesthesia-Related Teaching Rules
From Medicare Internet-only Manual, Chapter 12, Section 50.
Payment at Personally Performed Rate:
Physician personally performed the entire anesthesia service alone
The physician is involved with one anesthesia case with a resident, the physician is a teaching physician
The physician is involved in the training of physician residents in a single anesthesia case, two concurrent anesthesia cases involving residents or a single anesthesia case involving a resident that is concurrent to another case paid under the medical direction rules.
The physician is continuously involved in a single case involving a student nurse anesthetist
The physician is continuously involved in one anesthesia case involving a CRNA (or AA)
The physician and the CRNA (or AA) is involved in one anesthesia case and the services of each are found to be medically necessary.
Payment at the Medically Directed Rate
The physician can medically direct two, three, or four concurrent procedures involving qualified individuals, all of whom could be CRNAS, AAs, interns, residents, or combinations of these individuals.
The GC modifier is reported by the teaching physician to indicate he rendered the service in compliance with the teaching physician requirements in the Medicare Claims Processing Manual, Chapter 12, §100.1.2. One of the payment modifiers must be used in conjunction with the GC modifier.
Glossary
Add-on Codes: Procedures commonly carried out in addition to the primary procedure performed.
Anesthesiologist Assistant: A health professional who has completed an accredited anesthesia assistant training program.
Anesthesiologist: A physician licensed to practice medicine and has completed an accredited anesthesiology program.
Anesthesia Time: Begins when the anesthesiologist (or anesthesia provider) begins to prepare the patient for the induction of anesthesia and ends when the anesthesiologist (or anesthesia provider) is no longer in personal attendance.
Arterial Line: A catheter inserted into an artery, used most commonly to measure real-time blood pressure, and obtain samples for arterial blood gas.
Base Unit Value: Value assigned to anesthesia codes for anesthetic management of surgery and diagnostic tests.
Cardiopulmonary Bypass (CPB): A technique used to take over temporarily the function of the heart and lungs.
CRNA (Certified Registered Nurse Anesthetist): A registered nurse who has completed an accredited nurse anesthesia training program.
Controlled Hypotension: A technique used in general anesthesia to reduce blood pressure to control bleeding during surgery.
Conversion Factor: A unit multiplier to convert anesthesia units into a dollar amount for anesthesia services.
Central Venous Catheter: A catheter placed in a large vein such as the internal jugular, subclavian, or femoral vein with the tip of the catheter close to the atrium, or in the right atrium of the heart.
CVP (Central Venous Pressure): A direct measurement of the blood pressure in the right atrium and vena cava.
Emergency: A delay in treatment would lead to significant increase in the threat to life or body part.
Flat Fee: A flat fee is based on the physician fee schedule.
General Anesthesia: Drug-induced loss of consciousness during which patients cannot be aroused.
Hypothermic Circulatory Arrest: Implies a temperature of 20 degrees centigrade or less.
Medical Direction: Occurs when an anesthesiologist is involved in two, three, or four concurrent anesthesia procedures.
Medical Supervision: Occurs when an anesthesiologist is involved in five or more concurrent anesthesia procedures or fails to meet required medical direction criteria.
Monitored Anesthesia Care: Refers to a technique for many surgical procedures that do not require deep sedation or a general anesthetic.
PAC-Pulmonary Artery Catheter (e.g., Swan-Ganz): A flow-directed catheter inserted into the pulmonary artery.
Physical Status Modifier: A modifier used to report the physical status assigned to each patient undergoing anesthesia.
Pump Oxygenator: Term used when a cardiopulmonary bypass (CPB) machine is used to function as the heart and lungs.
Qualifying Circumstances: Circumstances significantly affecting the character of an anesthesia service.
Regional Anesthesia: Loss of sensation in a region of the body, produced by application of an anesthetic agent.
Relative Value Unit: Unit measure used to assign a value to services.
Resident (anesthesia resident): A physician who has completed his or her medical degree and entered a residency program specifically for anesthesiology training.
SRNA (Student Registered Nurse Anesthetist): An advanced practice registered nurse training in an accredited nurse anesthesia program.
Surgical Field Avoidance: Anesthesia provider avoids an area where the surgeon is working (usually on procedures around the head, neck, or shoulder girdle).
Total Body Hypothermia: Deliberate reduction of a patient's total body temperature, reducing the general metabolism of the tissues.