Always leave blank spaces in your calendar to accommodate the unexpected, because the unexpected is often more important than the expected.

- Lee Cockerell, Creating Magic

Whether or not you're into time management and keeping a careful schedule, you know how quickly an emergency can derail even your most carefully laid plans.  And that's the thing about planning - you can't plan for the unexpected.  Or can you? 

As Lee Cockerell suggests, what if it's as simple as leaving blocks of time open in your daily schedule to allow for whatever may arise?  I personally have starting putting a block in the morning and a block in the afternoon with the nice, friendly message "Don't Panic" as the title (suggested reading: this).  So far, so good, as it's always easier to remove those block and move things forward in your schedule than it is to move them back.