For an observation encounter spanning three days, which code applies for the discharge on the third day?

In the context of observation services, code 99217 is specifically designated for use during the discharge of a patient from observation care. This encounter can occur after a patient has been observed for a period, typically involving a comprehensive assessment of the patient's condition before concluding the observation stay.

The criteria for billing this code typically include the following: the patient's stability, the evaluation of the clinical status, and the provision of follow-up instructions upon discharge. This code implies that the physician performed the necessary tasks related to the discharge process for a patient who had been undergoing observation.

The other codes listed have distinct meanings and contexts in coding for evaluation and management services. Code 99291 is intended for critical care services that are considerably different from observation care; codes 99224 and 99220 are used for diagnostic services during the observation stay but do not apply to the discharge process itself. Thus, 99217 is appropriately used for documenting the discharge encounter for a patient after a multi-day observation period.