Randomized study of efficacy of flushing to avoid venous pain in colorectal or gastric cancer patients who are receiving oxaliplatin through peripheral vein

Interventions: 1st cycle : normal saline solution 2nd cycle : 5% glucose solution 1st cycle : 5% glucose solution 2nd cycle : normal saline solution Primary outcome(s): To evaluate the application site pain with NRS Study Design: Parallel Randomized