When concentrated medical fluids are injected from the Y-site during infusions by such means as the intravenous push or piggyback techniques, drugs occasionally separate out due to their incompatibility. A technique called “flushing” is used to prevent this from happening. This involves the injection of a washing solution, such as physiological saline or glucose solution, from the Y-site before and/or after injection. However, no standards have been established for the use of this technique. To ascertain the most efficient flushing conditions, we studied the relationship among the amount of residual drug in the intravenous tubing, and the volume and rate of flow of the flushing solution (physiological saline) injected from the Ysite with an injectable furosemide (Lasix® Injection). The results showed that the volume of physiological saline required to prevent drug incompatibility by flushing out the intravenous tubing was five to six times the inner volume of intravenous tubing, but the flushing rate did not have any effect on flushing.
