Monitored Anesthesia Care
Monitored anesthesia care (MAC) is a set of anesthesia services defined by the type of anesthesia personnel present during a procedure, not specifically by the level of anesthesia needed. The American Society of Anesthesiologists (ASA) defined MAC, and the following is derived from the ASA's statements:
"Monitored anesthesia care is a specific anesthesia service for a diagnostic or therapeutic procedure. Indications for monitored anesthesia care include the nature of the procedure, the individual's clinical condition and/or the potential need to convert to a general or regional anesthetic.
Monitored anesthesia care includes all aspects of anesthesia care-a pre-procedure visit, intra-procedure care, and post-procedure anesthesia management. During monitored anesthesia care, the anesthesiologist provides or medically directs a number of specific services, including but not limited to:
Diagnosis and treatment of clinical problems that occur during the procedure
Monitored anesthesia care may include varying levels of sedation, analgesia, and anxiolysis as necessary. The provider of monitored anesthesia care must be prepared and qualified to convert to general anesthesia when necessary. If the individual loses consciousness and the ability to respond purposefully, the anesthesia care is a general anesthetic, irrespective of whether airway instrumentation is required."
In 2004 (amended in 2014), ASA defined 4 levels of sedation and analgesia, as shown in Table 1.
Table 1. ASA's Definitions of General Anesthesia and Levels of Sedation and Analgesia
Terms | Minimal Sedation (Anxiolysis) | Moderate Sedation or Analgesia (Conscious Sedation) | Deep Sedation or Analgesia | General Anesthesia |
Responsiveness | Normal response to verbal stimulation | Purposeful response to verbal or tactile stimulation | Purposeful response following repeated or painful stimulation | Unarousable even with painful stimulation |
Airway | Unaffected | No intervention required | Intervention may be required | Intervention often required |
Spontaneous ventilation | Unaffected | Adequate | May be inadequate | Frequently inadequate |
Cardiovascular function | Unaffected | Usually maintained | Usually maintained | May be impaired |
Adapted from American Society of Anesthesiologists (2013).
ASA: American Society of Anesthesiologists.
Because sedation is a continuum, it is not always possible to predict how an individual will respond. Hence, practitioners intending to produce a given level of sedation should be able to rescue individuals whose level of sedation becomes deeper than initially intended. Individuals administering moderate sedation or analgesia (conscious sedation) should be able to rescue individuals who enter a state of deep sedation or analgesia, while those administering deep sedation or analgesia should be able to rescue individuals who enter a state of general anesthesia.
Sedation for Diagnostic and Therapeutic Procedures
Multiple diagnostic and therapeutic procedures performed in the outpatient setting (e.g., endoscopy, colonoscopy, bronchoscopy, interventional pain management procedures) rely on some degree of sedation for anxiolysis and pain control. Regardless of sedation depth, sedation and anesthesia services provided in outpatient settings should be administered by qualified and appropriately trained personnel. Moderate sedation is generally sufficient for many diagnostic and uncomplicated therapeutic procedures. Moderate sedation using benzodiazepines, with or without narcotics, is frequently administered under the supervision of the proceduralist.
According to the ASA's standard for monitoring, MAC should be provided by qualified anesthesia personnel, including physicians and nurse specialists. By this standard, the personnel must be, in addition to the proceduralist, present continuously to monitor the individual and provide anesthesia care. For individuals at high risk of an unsuccessful procedure under moderate sedation, this allows for the safe continuation of the procedure under deep sedation or general anesthesia by trained personnel.
Moderate sedation can be achieved using pharmacologic agents for sedation, anxiolysis, and analgesia. A frequently used combination is an opioid and benzodiazepine (e.g., fentanyl with midazolam) at doses individualized to obtain the desired sedative effect. Other combinations have also been used. While benzodiazepines and opioids can cause respiratory depression, effective reversal agents exist for both.
Propofol has increasingly been used to provide sedation for procedures. It is associated with a rapid onset of action and fast recovery from sedation. However, there are concerns about potential adverse effects and safety when used by non-anesthesiologists. Propofol has the potential to induce general anesthesia, and there is no pharmacologic antagonist to reverse its action. When used as moderate sedation, propofol may be administered by anesthesia personnel or under the direction of the proceduralist. ASA has offered practice guidelines for the provision of sedation by non-anesthesiologists, stating that personnel must be prepared to respond to deep sedation and loss of airway protection should these complications inadvertently occur during sedation.
Regulatory Status
In 1989, propofol Diprivan® (AstraZeneca) was approved by the U.S. Food and Drug Administration (FDA) through the premarket approval process for the induction and maintenance of anesthesia. The current FDA-approved label for Diprivan® states that it is indicated for initiation and maintenance of MAC sedation, combined sedation, and regional anesthesia; the label also states that Diprivan® is indicated for the sedation of adults in the intensive care unit who have been intubated or mechanically ventilated. Moreover, Diprivan® is also approved for induction of general anesthesia in individuals 3 years of age and older and maintenance of general anesthesia in individuals 2 months of age and older.
Many other FDA-approved medications for pain relief, anxiolysis, and sedation may be used in outpatient sedation.
The use of monitored anesthesia care may be considered medically necessary for gastrointestinal endoscopy, bronchoscopy, and interventional pain procedures when there is documentation by the proceduralist and anesthesiologist that specific risk factors or significant medical conditions are present.Those risk factors or significant medical conditions include any of the following:
Table PG1: ASA's Physical Status Classification System
Class | Definition |
ASA I | A normal, healthy patient |
ASA II | A patient with mild systemic disease |
ASA III | A patient with severe systemic disease |
ASA IV | A patient with severe systemic disease that is a constant threat to life |
ASA V | A moribund patient who is not expected to survive without the operation |
ASA VI | A declared brain-dead patient whose organs are being harvested |
ASA: American Society of Anesthesiologists
The use of monitored anesthesia care is considered not medically necessary for gastrointestinal endoscopic, bronchoscopic, or interventional pain procedures in individuals at average risk related to use of anesthesia and sedation
00635 | 01936 | 01991 | 00520 | 00740 | 00810 | 96373 |
96374 |
C15.3 | C15.4 | C15.5 | C15.8 | C15.9 | C16.0 | C16.1 |
C16.2 | C16.3 | C16.4 | C16.5 | C16.6 | C16.8 | C16.9 |
C17.0 | C17.1 | C17.2 | C17.3 | C17.8 | C17.9 | C18.0 |
C18.1 | C18.2 | C18.3 | C18.4 | C18.5 | C18.6 | C18.7 |
C18.8 | C18.9 | C19 | C20 | C21.0 | C21.1 | C21.2 |
C21.8 | C22.0 | C22.1 | C22.2 | C22.3 | C22.4 | C22.7 |
C22.8 | C22.9 | C23 | C24.0 | C24.1 | C24.8 | C24.9 |
C25.0 | C25.1 | C25.2 | C25.3 | C25.4 | C25.7 | C25.8 |
C25.9 | C26.0 | C26.1 | C26.9 | C34.00 | C34.01 | C34.02 |
C34.10 | C34.11 | C34.12 | C34.2 | C34.30 | C34.31 | C34.32 |
C34.80 | C34.81 | C34.82 | C34.90 | C34.91 | C34.92 | D01.0 |
D01.1 | D01.2 | D01.3 | D01.40 | D01.49 | D01.5 | D01.7 |
D01.9 | D02.20 | D02.21 | D02.22 | D12.0 | D12.1 | D12.2 |
D12.3 | D12.4 | D12.5 | D12.6 | D12.7 | D12.8 | D12.9 |
D13.0 | D13.1 | D13.2 | D13.3 | D13.30 | D13.39 | D13.4 |
D13.5 | D13.6 | D13.7 | D13.9 | D14.30 | D14.31 | D14.32 |
G56.40 | G56.41 | G56.42 | G56.43 | G57.70 | G57.71 | G57.72 |
G57.73 | G89.0 | G89.11 | G89.12 | G89.18 | G89.21 | G89.22 |
G89.28 | G89.29 | G89.3 | G89.4 | G90.50 | G90.511 | G90.512 |
G90.513 | G90.519 | G90.521 | G90.522 | G90.523 | G90.529 | G90.59 |
J40 | J41 | J41.0 | J41.1 | J41.2 | J41.8 | J42 |
J43.0 | J43.1 | J43.2 | J43.8 | J43.9 | J44.0 | J44.1 |
J44.9 | J45.20 | J45.21 | J45.22 | J45.30 | J45.31 | J45.32 |
J45.40 | J45.41 | J45.42 | J45.50 | J45.51 | J45.52 | J45.901 |
J45.902 | J45.909 | J47.0 | J47.1 | J47.9 | J96.00 | J96.01 |
J96.02 | J96.10 | J96.11 | J96.12 | J96.20 | J96.21 | J96.22 |
J96.90 | J96.91 | J96.92 | J98.01 | J98.09 | J98.11 | J98.19 |
J98.2 | J98.3 | J98.4 | J98.51 | J98.59 | J98.6 | J98.8 |
J98.9 | J99 | K80.00 | K80.01 | K80.10 | K80.11 | K80.12 |
K80.13 | K80.18 | K80.19 | K80.20 | K80.21 | K80.30 | K80.31 |
K80.32 | K80.33 | K80.34 | K80.35 | K80.36 | K80.37 | K80.40 |
K80.41 | K80.42 | K80.43 | K80.44 | K80.45 | K80.46 | K80.47 |
K80.50 | K80.51 | K80.60 | K80.61 | K80.62 | K80.63 | K80.64 |
K80.65 | K80.66 | K80.67 | K80.70 | K80.71 | K80.80 | K80.81 |
K81.0 | K81.1 | K81.2 | K81.9 | K82.0 | K82.1 | K82.2 |
K82.3 | K82.4 | K82.8 | K82.9 | K82.A1 | K82.A2 | K83.01 |
K83.09 | K83.1 | K83.2 | K83.3 | K83.4 | K83.8 | K83.9 |
K85.00 | K85.01 | K85.02 | K85.10 | K85.11 | K85.12 | K85.20 |
K85.21 | K85.22 | K85.30 | K85.31 | K85.32 | K85.80 | K85.81 |
K85.82 | K85.90 | K85.91 | K85.92 | K86.0 | K86.1 | K86.2 |
K86.3 | K86.81 | K86.89 | K86.9 | K87 | M25.50 | M25.511 |
M25.512 | M25.519 | M25.521 | M25.522 | M25.529 | M25.531 | M25.532 |
M25.539 | M25.541 | M25.542 | M25.549 | M25.541 | M25.542 | M25.549 |
M25.551 | M25.552 | M25.559 | M25.561 | M25.562 | M25.569 | M25.571 |
M25.572 | M25.579 | M54.00 | M54.01 | M54.02 | M54.03 | M54.04 |
M54.05 | M54.06 | M54.07 | M54.08 | M54.09 | M54.10 | M54.11 |
M54.12 | M54.13 | M54.14 | M54.15 | M54.16 | M54.17 | M54.18 |
M54.2 | M54.30 | M54.31 | M54.32 | M54.40 | M54.41 | M54.42 |
M54.5 | M54.6 | M54.81 | M54.89 | M54.9 | M79.60 | M79.601 |
M79.602 | M79.603 | M79.604 | M79.605 | M79.606 | M79.609 | M79.621 |
M79.622 | M79.629 | M79.631 | M79.632 | M79.639 | M79.641 | M79.642 |
M79.643 | M79.644 | M79.645 | M79.646 | M79.651 | M79.652 | M79.659 |
M79.661 | M79.662 | M79.669 | M79.671 | M79.672 | M79.673 | M79.674 |
M79.675 | M79.676 | R52 | Z12.0 | Z12.10 | Z12.11 | Z12.12 |
Z12.13 | Z12.2 | Z13.811 | Z13.83 | Z80.0 | Z80.2 | Z82.5 |
Z83.6 | Z83.71 | Z83.79 | Z85.00 | Z85.01 | Z85.020 | Z85.028 |
Z85.030 | Z85.038 | Z85.040 | Z85.048 | Z85.110 | Z85.118 | Z86.010 |
Practice Guidelines and Position Statements
American Society of Anesthesiologists
In 2014, the American Society of Anesthesiologists (ASA) updated its statement on the safe use of propofol:
"The Society believes that the involvement of an anesthesiologist in the care of every individual undergoing anesthesia is optimal. However, when this is not possible, non-anesthesia personnel who administer propofol should be qualified to rescue individuals whose level of sedation becomes deeper than initially intended and who enter, if briefly, a state of general anesthesia."
"Rescue" was defined as correcting "adverse physiologic consequences of the deeper-than-intended level of sedation (such as hypoventilation, hypoxia, and hypotension) and returns the individual to the originally intended level."
In 2016, ASA updated its statement on anesthetic care during interventional pain procedures. ASA indicated that:
"Many individuals can undergo interventional pain procedures without the need for supplemental sedation in addition to local anesthesia. For most individuals who require supplemental sedation, the physician performing the interventional pain procedure(s) can provide moderate (conscious) sedation as part of the procedure. For a limited number of individuals, a second provider may be required to manage moderate or deep sedation or, in selected cases other anesthesia services….
Significant anxiety may be an indication for moderate (conscious) sedation or anesthesia services. In addition, procedures that require the individual to remain motionless for a prolonged period of time and/or remain in a painful position may require sedation or anesthesia services. Examples of such procedures include but are not limited to sympathetic blocks (celiac plexus, paravertebral and hypogastric), chemical or radiofrequency ablation, percutaneous discectomy, trial spinal cord stimulator lead placement, permanent spinal cord stimulator generator and lead implantation, and intrathecal pump implantation. Major nerve/plexus blocks are performed less often in the chronic pain clinic, but the Committee believes that these blocks may more commonly require moderate (conscious) sedation or anesthesia services (e.g., brachial plexus block, sciatic nerve block, and continuous catheter techniques)."
In 2014, ASA updated its statement on respiratory monitoring during endoscopic procedures. The statement advised that "Monitoring for exhaled carbon dioxide should be conducted during endoscopic procedures in which sedation is provided with propofol alone or in combination with opioids and/or benzodiazepines, and especially during these procedures on the upper gastrointestinal tract."
Guidelines on sedation during gastrointestinal endoscopy were released in 2018 by the American Society for Gastrointestinal Endoscopy (ASGE). The guidelines stated that anesthesia provider assistance during gastrointestinal endoscopy should be considered in the following situations: prolonged or therapeutic endoscopic procedures requiring deep sedation, anticipated intolerance to standard sedatives, increased risk for adverse event because of severe comorbidity (ASA class IV or V), and increased risk for airway obstruction because of anatomic variant. The guidelines made the following recommendations for the use of propofol during endoscopies:
In 2015, ASGE published quality indicators for all gastrointestinal endoscopic procedures. Specific to this evidence review, ASGE stated: "Individuals administering moderate sedation should be able to rescue individuals who enter a state of deep sedation, whereas those administering deep sedation should be able to rescue inidividuals who enter a state of general anesthesia."
In 2013, ASGE published guidelines for endoscopic modification for geriatric individuals. Specific to this evidence review, ASGE recommended "standard monitoring procedures in the elderly during moderate sedation with heightened awareness of this population's increased response to sedatives."
In 2014, ASGE issued guidelines on the safety of the endoscopy unit, which made several recommendations on procedural sedation: "Staff Recommendations for intra-procedure care based on level of sedation
In 2009, ASGE-along with the American Association for the Study of Liver Diseases, American College of Gastroenterology, and American Gastroenterological Association-issued a joint position statement on non-anesthesiologist administration of propofol (NAAP) for gastrointestinal endoscopy. The societies found that NAAP was as safe and effective as anesthesiologist-administered propofol. They asserted that proper training and proper individual selection were necessary for the safe practice of NAAP sedation.
European Society of Gastrointestinal Endoscopy et al
The European Society of Gastrointestinal Endoscopy, as well as the European Society of Gastroenterology and Endoscopy Nurses and Associates, updated their guidelines on NAAP in 2015. Table 2 summarizes the main recommendations.
Table 2. Recommendations on NAAP for GI Endoscopy
Recommendation |
SOR |
QOE |
1. Before NAAP, individual assessment of physical status, age, body mass index, Mallampati's classification, and obstructive sleep apnea risk factors |
Strong |
Moderate |
2. Primary involvement of an anesthesiologist for high risk individualsa |
Weak |
Low |
3. Capnographic monitoring in high risk individuals, intended deep sedation, and long procedures |
Weak |
High |
4. Propofol monotherapy except in particular situations |
Weak |
High |
5. Administration of propofol through intermittent bolus infusion or perfusor systems, including target-controlled infusion and individual-controlled sedation |
Strong |
High |
6. Individual listen to self-selected music during upper and lower GI endoscopy procedures |
Weak |
Moderate |
7. Do not use pharyngeal anesthesia during propofol sedation for upper GI endoscopy |
Weak |
Moderate |
8. Use post-anesthetic discharge scoring system to determine individualdischarge |
Weak |
Low |
9. For individuals of ASA class >2, upon discharge, individualshould be accompanied by a responsible person and refrain from driving, drinking alcohol, operating heavy machinery, or engaging in legally binding decisions for 24 hours. Advice should be provided verbally and in written form |
Strong |
Low |
10. For individuals of ASA classes 1-2 who have received low-dose propofol monotherapy, a 6-hour limit is suggested |
Weak |
Low |
ASA: American Society of Anesthesiologists; GI: gastrointestinal; NAAP: non-anesthesiologist-administered propofol; QOE: quality of evidence; SOR: strength of recommendation.
aASA class ≥3, with a Mallampati's class ≥3 or other conditions that put them at risk of airway obstruction, in individuals receiving significant amounts of narcotic analgesics, or in long-lasting procedures.
Internal Medical Policy Committee 11-14-2019 Annual Review
Current medical policy is to be used in determining a Member's contract benefits on the date that services are rendered. Contract language, including definitions and specific inclusions/exclusions, as well as state and federal law, must be considered in determining eligibility for coverage. Members must consult their applicable benefit plans or contact a Member Services representative for specific coverage information. Likewise, medical policy, which addresses the issue(s) in any specific case, should be considered before utilizing medical opinion in adjudication. Medical technology is constantly evolving and the Company reserves the right to review and update medical policy periodically.