CPT code for 48 hours observation?

Does anyone know what CPT code to use for the 2nd day of service of a 48 hour observation patient?

observation codes

99218, 99219, 99220. discharge is 99217. It is expected that the patient will be discharged the second day (99217). In the RARE circumstances that they are still in observation use an outpatient/office visit E/M.

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Thanks,
Paula