What is the correct sequence to obtain a sterile urine sample from an indwelling catheter?

• A. Clamp the catheter, clean the port with alcohol, withdraw urine with sterile syringe
• B. Remove catheter, collect from collection bag
• C. Unclamp, aspirate from drainage port with non-sterile syringe
• D. Collect from the urethral meatus

Answer: (A)

Obtaining a sterile urine sample from an indwelling catheter requires aseptic technique and using the catheter’s dedicated sampling port. Clamping the catheter temporarily lets sterile urine pool in the sampling port so you can draw it without drawing from the bag. Cleaning the port with an alcohol wipe reduces surface bacteria that could contaminate the specimen. Using a sterile syringe to withdraw the urine preserves the sample’s sterility, giving an accurate representation of bladder urine rather than something contaminated by the catheter surface or drainage system. After collecting, unclamp the catheter to resume drainage.

Collecting from the collection bag exposes the specimen to contamination and does not provide a true sterile sample. Using a non-sterile syringe or aspirating from the drainage system without proper sterile technique risks introducing organisms. Collecting from the urethral meatus is nonsterile and not representative of bladder urine, leading to inaccurate results and infection risk.