ICD-10 Coding: Moderate “Conscious” Sedation vs. “Monitored” Sedation – Are you compliant?

Coders must ensure documentation supports the service, either moderate sedation or MAC.

Coding moderate sedation (or conscious sedation) and monitored anesthesia care (MAC) is not difficult; however, distinguishing what the services provided are and deciphering conflicted information about which physicians can report what codes can be confusing for some coders and physicians.

Misinterpretation Clouds Payer Judgement
History and changing terminology play a role in the confusion. Until the mid-1980s, anesthesiologists classified anesthesia into three types: general, regional, and local standby. Some payers, however, interpreted “standby” in the literal sense—mistakenly thinking the anesthesiologist was “standing by” and not providing a service—and would not pay for local standby services.

To clear up the confusion, the American Society of Anesthesiologists (ASA) replaced the term “standby” anesthesia with “monitored anesthesia care,” approving its first position statement on MAC in 1986. Both the new term and position statement demonstrated active involvement in patient care. In 1998, the MAC position statement was revised and the concept of a sedation continuum as illustrated by L. Charles Novak, M.D. became part of ASA’s efforts to educate non-anesthesiologists about conscious sedation (Cohen/McMichael, 2004). The MAC position statement was last updated Sept. 2, 2008.

MAC vs. Moderate Sedation
MAC services are rendered by anesthesia providers who aren’t involved in the diagnostic or procedural service and include the same care as any other anesthesia service: a pre-anesthesia assessment, documentation of vital signs during the procedure, and post anesthesia patient care. If necessary, the anesthesia provider must convert to a general anesthetic, which requires anesthesia training.

In contrast, moderate (conscious) sedation, as defined by the CPT^®, closely matches the ASA’s definition of a drug induced depression of consciousness. CPT^® further indicates that moderate sedation does not include the MAC codes (00100-01999) found in the anesthesia section of the CPT^® book. In 2017, CPT® added new Moderate sedation codes 99151-99157 after removing the symbol, that represented “including moderate sedation” from hundreds of procedural and diagnostic codes. The codes 99151-99153 require the conscious sedation service be provided by the same physician performing the diagnostic or therapeutic service, along with an independent trained observer to assist in monitoring the patient.

Many payers, also require the physician to document their supervision of the sedation services in their procedural note, not just refer to nurse’s sedation note. Codes 99154-99157 require the sedation service be provided by a physician other than the one performing the diagnostic or therapeutic codes, but an independent trained observer is not required. There are additional CPT^® instructions for services performed in a facility or non-facility setting, as well as exclusions for codes listed in Appendix G of the CPT^® book. These codes are first based on age of patient, then how much “intraservice” time was spent, supervising the sedation services.

Although a coder may expect that anesthesia codes are only reported by trained anesthesia providers, existing insurance policies indicate non-anesthesia providers will be reimbursed when billing the appropriate anesthesia codes. The billing physician, however, must report anesthesia time in minutes and meet the requirements for MAC as defined by the ASA. An anesthesia modifier (G8 Monitored anesthesia care (MAC) for deep complex, complicated, or markedly invasive surgical procedure, G9 Monitored anesthesia care for a patient who has a history of severe cardio-pulmonary condition, or QS Monitored anesthesia care service) identifying the service must also be appended.

Several Medicare Administrative Contractors (MACs), formerly known as fiscal intermediaries, have published Local Coverage Determinations (LCD) related to MAC services. Statistical anesthesia modifiers are required to track MAC cases.

Since 1992, all Medicare contractors require the anesthesia modifier QS, and LCD’s will identify those carriers that require G8 and G9. Usually, it isn’t necessary to report both modifier QS and either modifier G8 or modifier G9 (as applicable to the patient due to high risk) because each of these anesthesia modifiers indicate MAC was used during the procedure. If the procedure converts from a MAC to general anesthesia, no modifier is necessary.

Coders must understand the reported and billed service, and ensure documentation supports the reported service, whether it is moderate sedation or MAC. It is also important to follow Medicare LCD and medical necessity guidelines for any procedure performed. American Society of Anesthesiologists (ASA) Definitions Monitored anesthesia care and moderate sedation are clinically distinct services.

Here’s how the ASA defines each:

Moderate sedation/analgesia (conscious sedation) Codes 99151-99157, 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.

Independent trained observer: The physician or qualified healthcare provider would supervise an independent, trained observer in monitoring the patient during the procedure. The trained observer must not have any other duties during the procedure.

Note: Reflex withdrawal from a painful stimulus is NOT considered a purposeful response. Possible Moderate (conscious) Sedation Medications: Benadryl®, Versed®, Demerol® to name a few.

Monitored anesthesia care (MAC), like Propofol® for example, Codes 00100-01999, 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.

MAC 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 the following:

• 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

MAC 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.

MAC is a physician service provided to an individual patient. It should be subject to the same level of payment as general or regional anesthesia. Accordingly, the ASA Relative Value Guide® provides for the use of proper base procedural units, time units and modifier units as the basis for determining payment.

Moderate Conscious Sedation is paid separately, but there is a sliding scale based on place of service. Further, In the physician RVU file there is a column labeled “PCTC IND” which designates when a code is technical-only or professional-only. The add-on code for each additional 15 minutes of moderate sedation by the physician performing the procedure (99153) is indicated as technical-only (3) in this field. In addition, there is an NA in the RVU file column titled “FACILITY NA INDICATOR”. The NA indicates “that this procedure is rarely or never performed in the facility setting”. Since code 99153 is technical only, a physician cannot report this code when performed in the facility setting.

The other moderate sedation codes (99151, 99152, 99155, 99156, and 99157) are assigned a “9” indicating the TC/PC concept doesn’t apply; there are different RVU values for facility and non-facility site of service. The NA is not in the “FACILITY NA INDICATOR” column for these other codes.

When a physician performing the procedure oversees moderate sedation in the facility setting, only a code describing the initial 15 minutes of sedation (99151 or 99152) may be reported when billing for the physician. The hospital may bill 99153 when documented (MUE is 9), or if the physician performed this service in POS 11, office, then it may be reported. The physician must still document all the required components of the moderate sedation as detailed in the CPT® codebook.

To be compliant with payer documentation, we offer the example below for appropriate physician documentation, for moderate conscious sedation.

“I attest that Moderate Conscious Sedation was provided under my direct supervision with the sedation trained nurse using 4mg of intravenous Versed and 75 mcg of Benadryl to sedate the patient.  Start time 8:24am and End time 8:45am. There were no complications. See nurse’s sedation sheet I signed and dated for further details. There were no complications.”