During urine collection from an indwelling catheter, which instruction is essential to avoid contamination?

• A. Never disconnect the catheter from the drainage tube due to contamination risk.
• B. Do not obtain urine from the catheter.
• C. Replace the catheter before sampling.
• D. Ignore labeling.

Answer: (A)

Maintaining a closed drainage system is essential when collecting urine from an indwelling catheter. Opening the system by disconnecting the catheter from the drainage tubing creates an entry point for bacteria from the perineal area or the environment, greatly increasing the risk of contaminating the sample and causing infection. To obtain a specimen without breaking the closed system, use the designated sampling port on the drainage tubing with sterile technique: clean the port, attach a sterile syringe, withdraw the urine, then cap and label the specimen. If you need more sample, repeat the closed-system method rather than disconnecting the catheter. The other options don’t address this contamination risk and aren’t appropriate for proper sampling.