IV Therapy (Venipuncture) Updated Cleaning Technique (Circular vs Back-and-Forth Friction) using ChloraPrep cleanser. When performing any type of venipuncture procedure (drawing blood, phlebotomy, or starting an IV), you want to properly clean the area before venipuncture. Updated guidelines from CLSI (Clinical and Laboratory Standards Institute) suggest that new evidence shows that a back and forth motion with friction is superior to a circular motion (from inside to outside). Always ref