Lay flat tubing is used as a fluid conductor for transferring fluid to and from the body of a patient. The lay flat tubing lies flat or collapsed when not in use, utilizing minimal space during transportation and storage, but which expands to form a passage when used to conduct fluid. A plurality of lumens may be formed in the lay flat tubing. At least one lumen transports infused fluid end-to-end from a source to an entry site on a patient, or in the alternative from an entry site on or in a patient. All lumens are isolated with respect to each other in order to prevent crossover of fluid from one lumen to the other.