What exactly are "suitcase handles" in a cockpit?
From the NTSB report


  "Suitcase handles" is a colloquial term for the longitudinal trim handles located on the center control
  pedestal. "Pickle switches" is a colloquial term for the trim switches located on the outboard side of each of
  the control wheels. 


The MD-80 cockpit is shown at this page, with the trim handles on the left side of the console (item 9).



Under normal operation, the pilot will use the switches on the control column to change the trim.  If there's a problem with the thumb switches, the handles on the console are available.