CNA Basic Nursing Skills 20 2 — Questions and Answers
Question 1: When collecting a clean-catch urine specimen, what instruction should the CNA give the resident?
- Collect the first portion of urine in the container
- Clean the urethral area, begin urinating into the toilet, then collect the midstream urine in the container (Correct answer)
- Collect the last portion of urine only
- Use any method that is most convenient for the resident
Correct answer: Clean the urethral area, begin urinating into the toilet, then collect the midstream urine in the container
A midstream clean-catch specimen reduces contamination from periurethral bacteria by first cleansing the area and discarding the initial urine stream before collection.
The initial stream of urine flushes bacteria from the urethra and periurethral area. By discarding the first portion and catching the midstream, contamination is minimized, improving the specimen's accuracy for culture and sensitivity testing. The periurethral area must be cleaned before collection. The CNA assists as needed based on the resident's ability while maintaining dignity.
Question 2: A 24-hour urine collection has begun. A resident urinated but the CNA forgot to collect it. What should the CNA do?
- Continue collecting from the next void without telling anyone
- Discard all collected urine and restart the 24-hour collection, notifying the nurse (Correct answer)
- Add more water to the collection bottle to compensate
- Estimate the amount missed and add water to the bottle
Correct answer: Discard all collected urine and restart the 24-hour collection, notifying the nurse
Missing a single void invalidates the entire 24-hour collection because the volume and composition of the urine collected will be incomplete and inaccurate.
A 24-hour urine collection measures substances excreted over a full day (creatinine, hormones, proteins). Missing any portion makes the result inaccurate. The correct action is to notify the nurse immediately, discard the incomplete collection, and restart with a new container. All team members must be informed of the restart so the schedule can be reset and all voids collected from that point forward.
Question 3: How should a stool specimen be collected?
- Collect from inside the toilet bowl with a tongue depressor
- Have the resident defecate into a clean container or hat, then transfer a small amount using the applicator provided (Correct answer)
- Collect a full bowel movement and place it in the specimen cup
- Use a sterile needle to aspirate stool from the rectum
Correct answer: Have the resident defecate into a clean container or hat, then transfer a small amount using the applicator provided
The resident defecates into a collection hat or clean container; a small amount is transferred with the applicator to the specimen cup to avoid contamination from toilet water.
Stool specimens are collected to test for occult blood, parasites, bacteria, or C. difficile. Toilet water contaminates the specimen and can cause false results. The resident uses a bedpan or collection hat placed under the toilet seat. The CNA wears gloves, uses the applicator from the specimen kit to collect a small amount, and places it in the labeled specimen cup. The specimen is labeled and sent to the lab promptly.
Question 4: A resident needs a sputum specimen. When is the best time to collect it?
- Immediately after a meal
- In the morning upon waking, before eating or oral hygiene (Correct answer)
- During afternoon rest time
- After vigorous exercise
Correct answer: In the morning upon waking, before eating or oral hygiene
Sputum is most concentrated and easiest to expectorate in the morning before oral hygiene or eating, providing the best specimen quality.
During sleep, respiratory secretions accumulate in the airways. Morning collection before oral care avoids contamination from oral bacteria and yields a more representative lower respiratory specimen. The CNA instructs the resident to take deep breaths and cough deeply (not just spit), directing mucus from the lungs — not saliva — into the sterile specimen cup. The cup should not be touched on the inside.
Question 5: Which of the following is essential when labeling a specimen before sending it to the laboratory?
- The CNA's name only
- The resident's full name, date of birth, date and time of collection, and type of specimen (Correct answer)
- The time of collection only
- The nurse's name and room number
Correct answer: The resident's full name, date of birth, date and time of collection, and type of specimen
Complete, accurate labeling prevents specimen mix-ups and ensures results are matched to the correct resident.
Specimen mislabeling is a serious patient safety error that can lead to incorrect treatment. The minimum required identifiers typically include the resident's full name, date of birth (or facility ID), collection date and time, and specimen type. Most facilities also require the ordering nurse's or physician's name. The label is applied at the bedside immediately after collection, never in advance or retroactively.
Question 6: Why must a blood glucose specimen be taken at the scheduled time rather than early or late?
- Blood glucose is only accurate during specific times of the day
- Timing relative to meals directly affects glucose levels, so deviations make results uninterpretable (Correct answer)
- Lab equipment is only available at scheduled times
- The resident's insurance requires specific timing
Correct answer: Timing relative to meals directly affects glucose levels, so deviations make results uninterpretable
Blood glucose values are interpreted in the context of meals; fasting, pre-meal, and post-meal results have different normal ranges, so timing errors make clinical decisions unreliable.
Fasting glucose (before breakfast) tests baseline glucose without food influence. Post-prandial glucose (1-2 hours after eating) tests the body's glycemic response to meals. If timing is off, the physician cannot correctly interpret whether the resident's diabetes is controlled. The CNA performing or assisting with blood glucose monitoring should document the exact time and the resident's meal or fasting status alongside the glucose value.
CNA Basic Nursing Skills 20 2
When collecting a clean-catch urine specimen, what instruction should the CNA give the resident?