What does the phrase '4 hours after hanging' refer to in transfusion tubing usage?

• A. Time to hang the tubing after receiving blood
• B. Time to discard the tubing after use
• C. Maximum duration the tubing is usable after hanging
• D. Time the tubing remains sterile before use

Answer: (C)

The key idea is a safety rule for transfusion tubing: once you start the transfusion (when the blood product is hung), the tubing can be used for a maximum of four hours. This window helps limit bacterial growth and maintains the product’s safety while it’s exposed to room temperature. So the phrase four hours after hanging is referring to the total allowable time the tubing remains in use after you begin the transfusion. If the transfusion finishes within that four-hour window, you discard the tubing after completion; if the four-hour limit is reached and the transfusion isn’t finished, you stop, discard the remaining product and tubing, and start anew if more transfusion is needed.