This document addresses anesthesia services during gastrointestinal endoscopic procedures. Anesthesia services include all services associated with the administration and monitoring of analgesia or anesthesia to an individual in order to produce partial or complete loss of sensation. Examples of various methods of anesthesia include moderate sedation ("conscious sedation"), monitored anesthesia care (MAC), regional anesthesia and general anesthesia. This document addresses the medical necessity of anesthesia services. It does not address whether or not reimbursement is provided for the anesthesia service. This document is not intended to explain the billing and reimbursement of anesthesia. 

NOTE: Please see the following related document for additional information:

• CG-MED-21 Anesthesia Services and Moderate ("Conscious") Sedation

Medically Necessary: 

Moderate Sedation
Moderate sedation ("conscious sedation") ordered by the attending physician and administered by the surgeon or physician performing the gastrointestinal endoscopic procedure or an independent trained practitioner is considered medically necessary.

Other Types of Anesthesia Services including Monitored Anesthesia Care (for definition, see Discussion below)
Other types of anesthesia services including MAC are considered medically necessary during gastrointestinal endoscopic procedures when there is documentation by the operating physician and the anesthesiologist that demonstrates any of the following higher risk situations exist:

• Prolonged or therapeutic endoscopic procedure requiring deep sedation; or
• A history of or anticipated intolerance to standard sedatives (e.g., individual on chronic narcotics or benzodiazepines, or has a neuropsychiatric disorder); or
• Increased risk for complication due to severe comorbidity (American Society of Anesthesiologists [ASA] class III physical status or greater. See Appendix for physical status classifications); or
• Individuals over 70; or
• Individuals under the age of 18; or
• Pregnancy; or
• History of drug or alcohol abuse; or
• Uncooperative or acutely agitated individuals (e.g., delirium, organic brain disease, senile dementia); or
• Increased risk for airway obstruction due to anatomic variant including any of the following:
  • History of previous problems with anesthesia or sedation; or
  • History of stridor or sleep apnea; or
  • Dysmorphic facial features, such as Pierre-Robin syndrome or trisomy-21; or
  • Presence of oral abnormalities including but not limited to a small oral opening (less than 3 cm in an adult), high arched palate, macroglossia, tonsillar hypertrophy, or a non-visible uvula (not visible when tongue is protruded with individual in sitting position e.g., Mallampati class greater than II); or
  • Neck abnormalities including but not limited to short neck, obesity involving the neck and facial structures, limited neck extension, decreased hyoid-mental distance (less than 3 cm in an adult), neck mass, cervical spine disease or trauma, tracheal deviation, or advanced rheumatoid arthritis; or
  • Jaw abnormalities including but not limited to micrognathia, retrognathia, trismus, or significant malocclusion

Not Medically Necessary:

The routine assistance of an Anesthesiologist or Certified Registered Nurse Anesthetist (CRNA) for individuals not meeting the above criteria who are undergoing standard upper or lower gastrointestinal endoscopic procedures is considered not medically necessary.

The following codes for treatments and procedures applicable to this document are included below for informational purposes.  Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy.  Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

Adequate sedation and analgesia is an integral part of a diagnostic or therapeutic gastrointestinal procedure. Sedation may be defined as a drug-induced depression in the level of consciousness. The purpose of sedation and analgesia is to relieve an individual's discomfort and anxiety, improve the outcome of the examination and diminish the individual's memory of the event. In a joint statement on sedation in endoscopy issued by the American College of Gastroenterology (ACG), American Gastroenterological Association (AGA), and American Society for Gastrointestinal Endoscopy (ASGE) (2004), the recommendations included the following statements:

• In general, diagnostic and uncomplicated therapeutic endoscopy and colonoscopy are successfully performed with moderate ("conscious") sedation.
• The routine assistance of an anesthesiologist/anesthetist for average risk patients undergoing standard upper and lower endoscopic procedures is not warranted.
• Complex procedures and procedures in high-risk patients may justify the use of an anesthesiologist/anesthetist to provide conscious and/or deep sedation.

The ACG released a Position Statement (Vargo, 2009) which recommends that "the use of anesthesiologist-administered sedation for healthy, low-risk patients undergoing routine GI endoscopy results in higher costs with no proven benefit with respect to patient safety or procedural efficacy."

There is no single age cut-off for individuals in a pediatric age group that would clearly determine an individual to be at higher risk. Several organizations have proposed age cut-offs for monitored sedation ranging from 19 to 21 years and other organizations are silent regarding at what age an individual is no longer considered to be in the pediatric age group (American Academy of Pediatrics, 2006; ASGE, 2008a; National Institute for Health and Clinical Excellence, 2010). Typically by the age of 18, an individual will have finished growing in regards to facial structures and airway size.

Anesthesia services are provided by or under the supervision of a physician. Services consist of the administration of an anesthetic agent in various types of anesthesia.

Moderate Sedation: Involves the administration of medication with or without analgesia to achieve a state of depressed consciousness while maintaining the individual's ability to respond to stimulation. Moderate sedation is administered by the surgeon or physician performing the procedure or an independent trained practitioner for the purpose of assisting the physician in monitoring the individual's level of consciousness and physiological status. It includes pre- and post- sedation evaluations, administration of the sedation and monitoring of the cardiorespiratory function. Cardiorespiratory functions monitored include heart rate, blood pressure and oxygen level. 

Monitored Anesthesia Care (MAC)*: MAC was developed in response to the shift to providing more surgical and diagnostic services in an ambulatory, outpatient or office setting without the use of the traditional general anesthetic. Accompanying this, there has been a change in the provision of anesthesia services from the traditional general anesthetic to a combination of local, regional and certain conscious altering drugs. This type of anesthesia is referred to as MAC if directly provided by anesthesia personnel. Based on the American Society of Anesthesiologists' standards for monitoring, MAC should be provided by qualified anesthesia personnel (anesthesiologists or qualified anesthetists such as certified registered nurse anesthetists). These personnel must be continuously present to monitor the individual and provide anesthesia care.

As described by the ASA's Position on Monitored Anesthesia Care (2008):

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 patient'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 preprocedure visit, intraprocedure care and postprocedure 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
• Support of vital functions
• Administration of sedatives, analgesics, hypnotics, anesthetic agents or other medications as necessary for patient safety
• Psychological support and physical comfort
• Provision of other medical services as needed to complete the procedure safely

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 patient loses consciousness and the ability to respond purposefully, the anesthesia care is a general anesthetic, irrespective of whether airway instrumentation is required.

General Anesthesia: A reversible state of unconsciousness and the inability to perceive pain, produced by anesthetic agents, with absence of pain sensation over the entire body and a greater or lesser degree of muscular relaxation; the drugs producing this state can be administered by inhalation, intravenously, intramuscularly, rectally, or via the gastrointestinal tract. 

American Society of Anesthesiologists Levels of Sedation/Analgesia (2009) 

Minimal Sedation (Anxiolysis): is a drug-induced state during which patients respond normally to verbal commands. Although cognitive function and coordination may be impaired, airway reflexes, and ventilatory and cardiovascular functions are unaffected. 

Moderate Sedation/Analgesia ("Conscious Sedation"): is a drug-induced depression of consciousness during which patients respond purposefully** to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained. 

Deep Sedation/Analgesia: is a drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully** following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate. Cardiovascular function is usually maintained.

American Society of Anesthesiologists Definition of General Anesthesia (2009) 

General Anesthesia: is a drug-induced loss of consciousness during which patients are not arousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired. Patients often require assistance in maintaining a patent airway, and positive pressure ventilation may be required because of depressed spontaneous ventilation or drug-induced depression of neuromuscular function. Cardiovascular function may be impaired.

Because sedation is a continuum, it is not always possible to predict how an individual patient will respond. Hence, practitioners intending to produce a given level of sedation should be able to rescue*** patients whose level of sedation becomes deeper than initially intended. Individuals administering Moderate Sedation/Analgesia ("Conscious Sedation") should be able to rescue*** individuals who enter a state of Deep Sedation/Analgesia, while those administering Deep Sedation/Analgesia should be able to rescue*** patients who enter a state of General Anesthesia.

*Monitored Anesthesia Care does not describe the continuum of depth of sedation rather it describes "a specific anesthesia service in which an anesthesiologist has been requested to participate in the care of a patient undergoing a diagnostic or therapeutic procedure."

**Reflex withdrawal from a painful stimulus is NOT considered a purposeful response.

***Rescue of an individual from a deeper level of sedation than intended is an intervention by a practitioner proficient in airway management and advanced life support. The qualified practitioner corrects adverse physiologic consequences of the deeper-than-intended level of sedation (such as hypoventilation, hypoxia and hypotension) and returns the patient to the originally intended level of sedation. It is not appropriate to continue the procedure at an unintended level of sedation.

Peer Reviewed Publications:

1. Rex DK, Overley CA, Walker J. Registered nurse-administered propofol sedation for upper endoscopy and colonoscopy: Why? When? How? Rev Gastroenterol Disord. 2003; 3(2):70-80.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Academy of Pediatrics, American Academy of Pediatric Dentistry, Charles J. Coté, Stephen Wilson; The work group on sedation guidelines for monitoring and management of pediatric patients during and after sedation for diagnostic and therapeutic procedures: an update. Pediatrics. 2006; 118(6):2587-2602.
2. American College of Gastroenterology (ACG), the American Gastroenterological Association (AGA) and the American Society for Gastrointestinal Endoscopy (ASGE). Recommendations on the administration of sedation for the performance of endoscopic procedures. a joint statement of a working group from the American College of Gastroenterology (ACG), the American Gastroenterological Association (AGA) and the American Society for Gastrointestinal Endoscopy (ASGE). March 2004. Available at: http://www.acg.gi.org/physicians/nataffairs/trisociety.asp. Accessed on May 16, 2011.
3. American Society for Gastrointestinal Endoscopy. ASGE guideline: modifications in endoscopic practice for the elderly. Gastrointestinal Endoscopy. 2006; 63(4):566-569.
4. American Society for Gastrointestinal Endoscopy. Guidelines for conscious sedation and monitoring during gastrointestinal endoscopy. Gastrointest Endosc. 2003; 58(3):317-322.
5. American Society for Gastrointestinal Endoscopy. Modifications in endoscopic practice for pediatric patients. Gastrointestinal Endoscopy. 2008a; 67(1):1-9.
6. American Society for Gastrointestinal Endoscopy. Sedation and anesthesia in GI endoscopy. Gastrointestinal endoscopy. 2008b; 68(5):815-826.
7. American Society of Anesthesiologists. ASA position on monitored anesthesia care (approved by the House of Delegates on October 21, 1986; amended on October 25, 2005; last updated on September 2, 2008). For additional information visit the ASA website: http://www.asahq.org. Accessed on May 16, 2011.
8. American Society of Anesthesiologists. Continuum of depth of sedation definition of general anesthesia and levels of sedation/analgesia (approved by ASA House of Delegates on October 27, 2004, and amended on October 21, 2009). For additional information visit the ASA website: http://www.asahq. Accessed on May 16, 2011.
9. American Society of Anesthesiologists. Statement on respiratory monitoring during endoscopic procedures (approved by the ASA House of Delegates on October 21, 2009). For additional information visit the ASA website: http://www.asahq.org. Accessed on May 16, 2011.
10. American Society of Anesthesiologists task force on management of the difficult airway. Practice guidelines for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology. 2003; 98(5):1269-1277.
11. American Society of Anesthesiologists task force on sedation and analgesia by non-anesthesiologists. Practice guidelines for sedation and analgesia by non-anesthesiologists. Anesthesiology. 2002; 96(4):1004-1017.
12. Cohen LB, Delegge MH, Aisenberg J, et al. AGA Institute review of endoscopic sedation. Gastroenterology. 2007; 133(2):675-701.
13. National Institute for Health and Clinical Excellence. Clinical guideline 112. Sedation in children and young people: sedation for diagnostic and therapeutic procedures in children and young people. December 2010. Available at: http://www.nice.org.uk/nicemedia/live/13296/52130/52130.pdf. Accessed on June 17, 2011.
14. Vargo JJ, Cohen LB, Rex DK, Kwo PY. Position statement: Nonanesthesiologist administration of propofol for GI endoscopy. Am J Gastroenterol 2009; 104(12):2886–2892. Available at: http://www.acg.gi.org/members/nataffairs/Nonanesthesiologist_Administered_Propofol_Statement.pdf. Accessed on May 17, 2011.

Anesthesia Services, Gastrointestinal Endoscopic Procedures
Conscious Sedation, Gastrointestinal Endoscopic Procedures
General Anesthesia, Gastrointestinal Endoscopic Procedures
Moderate Sedation, Gastrointestinal Endoscopic Procedures
Monitored Anesthesia Care (MAC), Gastrointestinal Endoscopic Procedures

American Society of Anesthesiology Physical Status Classifications:

Class I: A normal healthy patient 

Class II: A patient with mild systemic disease

Class III: A patient with severe systemic disease

Class IV: A patient with severe systemic disease that is a constant threat to life

Class V: A moribund patient who is not expected to survive without the operation

Class VI: A declared brain-dead patient whose organs are being removed for donor purposes