Below is from AMA CPT Assistant 2006 and 2011, which describes an independent trained observer administering the agent under the order by the physician and the physician reporting CPT 99144 if at least 16 minutes was performed.
I don't see that this service would be reported by the ASC for a carrier that is billed with a CMS-1500 such as Medicare but it appears the physician could report the service if it is properly documented as formal moderate sedation record.
Question
If the physician does not administer the agent, are the moderate sedation codes appropriately reported?
AMA Comment
In the case of 99143-99145 where the physician is performing the diagnostic or therapeutic service provides the sedation and the presence of an independent, trained observer to assist in the monitoring of the patient's level of consciousness and physiological status is required, it is appropriate that the agent(s) be administered by the independent, trained observer under the orders of the physician performing the diagnostic or therapeutic service.
Question: The moderate sedation codes have a reference to the February 2006 issue of CPT Assistant in which instructions were published stating that a moderate sedation procedure performed by an independent observer on an adult that lasts 35 minutes would be reported with both code 99144 and code 99145. Do the new time guidelines in the CPT 2011 codebook override the instructions published in the February 2006 issue of CPT Assistant?
Answer: Yes. The new time guidelines published in the CPT 2011 codebook override the instructions published in the February 2006 issue of CPT Assistant. Based upon current CPT guidelines, the appropriate reporting of moderate sedation that lasts 35 minutes performed by an independent observer on an adult would be reported with the only code 99144. The rationale for reporting is that when codes are ranked in sequential typical times and the actual time is between two typical times, the code with the typical time closest to the actual time is used. The "35 minutes" is closer to the stated time in code 99144 (first 30 minutes intraservice time). A unit of time is attained when the midpoint has been passed. Therefore, in order to report an additional 15 minutes of intraservice time (as represented by codes 99145 and 99150), the midpoint of 7.5 minutes must be passed.
Question: Is it appropriate to report the moderate (conscious) sedation codes for the first 30 minutes of intraservice time if only 10 minutes of moderate sedation services are provided?
Answer: No. The standards for time measurement provided in the Introduction of the CPT 2011 codebook shall apply unless there are code or code-range-specific instructions in guidelines, parenthetical instructions, or code descriptors to the contrary. As there are no code or code-range-specific guidelines for the moderate (conscious) sedation codes, the general guidelines are to be applied. A unit of time is attained when the midpoint has been passed. Therefore, in order to report a code with a unit of time of 30 minutes, 16 minutes or more of the service described by the code must be provided. If the time threshold has not been met, then the code is not reportable.