99356, prolonged services inpatient

In order to bill 99356 w/ 99233 does the time for the 99356 have to be 1 hour over and above the 35 mins for the 99233 or at least an hour all together?

re: 99356, prolonged services inpatient

I would say over and above because the descriptor for 99356 says "beyond the usual service" and the introduction to that section says that a prolonged service of less than 30 minutes total duration is not separately reported because that is in the regular E/M codes.