Help! I start clinicals very soon and am trying to remember the procedure for backflushing secondary IV tubing! Do I lower the old/empty IVPB bag, and let the primary fluid run into it, then remove the old bag and attach the new IVPB med, prime, and set the pump (and lower the primary IV bag)? Are both primary and secondary clamps open or closed during the flushing? As long as the old and new IVPB meds are compatible, is backflushing always safe? Thanks so much for any help!