4.3 Specimen Collection and Therapeutic/Technical Procedures
Key Takeaways
- A clean-catch midstream urine specimen is collected after cleaning the perineal area and catching the sample mid-flow to avoid contaminating it with surface bacteria.
- A 24-hour urine collection discards the first void, saves every void for the next 24 hours, and must be restarted from the beginning if any void is missed.
- Every specimen must be labeled at the bedside immediately after collection with the resident's name, ID, date, time, and specimen type — never labeled in advance.
- Applying non-sterile dressings and elastic stockings (TED hose) is within a nurse aide's scope, but inserting catheters, giving injections, and performing venipuncture are not.
- When a resident or situation pressures a nurse aide to perform a task outside their scope, the correct response is always to decline and notify the nurse.
Collecting Specimens Accurately
Nurse aides frequently collect body specimens that the laboratory uses to help diagnose and monitor a resident's condition. Because a contaminated or mislabeled specimen can lead to a wrong result or a wasted, uncomfortable recollection, technique and labeling accuracy are heavily tested on the NNAAP exam.
Clean-Catch (Midstream) Urine Specimen
A clean-catch midstream urine specimen is collected to reduce contamination from skin bacteria so the lab result reflects what is actually inside the bladder. The technique:
- Wash hands and put on gloves.
- Clean the perineal area (front to back for a female resident; in a circular motion at the tip of the penis for a male resident) with the provided antiseptic wipes.
- Have the resident begin urinating into the toilet or bedpan, then move the sterile specimen container into the stream midstream — after the first few seconds of flow — to collect the sample without touching the container to the skin.
- Cap the container without touching the inside of the lid or container, and remove it before the resident finishes voiding.
Exam trap: a question may ask why the first few seconds of urine are not collected. The answer is that the initial flow washes away surface bacteria, and catching the specimen midstream keeps that bacteria out of the sample.
24-Hour Urine Collection
A 24-hour urine collection gathers every void over a full day to measure substances, such as protein or hormone levels, that vary throughout the day. Key points:
- The collection starts by having the resident void and discarding that first specimen (it is not saved), then noting the exact start time.
- Every urine void for the next 24 hours is saved in the collection container, which is typically kept on ice or refrigerated.
- The collection ends exactly 24 hours later, when the resident voids one final time and that last specimen is added to the container.
- If a single void is missed or accidentally discarded during the 24 hours, the entire collection is invalid and must be restarted — a detail exam writers like to test.
Stool Specimen Collection
A stool specimen is collected using a clean, dry bedpan or a specimen collection device fitted into the toilet, and it is never combined with urine, since urine can interfere with lab results. Using gloves and the tongue blade or scoop provided in the collection kit, a small sample is placed into the specimen container, which is then labeled and sent to the lab promptly. Some stool tests, such as a fecal occult blood test, may require the resident to avoid certain foods or medications beforehand per the nurse's instructions.
Labeling and Chain of Custody
Every specimen must have the right label on the right container at the right time — label the container at the bedside, immediately after collection, never in advance and never after leaving the room. A correct label includes the resident's full name, identification number, date, time of collection, and the type of specimen. An unlabeled or mislabeled specimen must be discarded and recollected rather than guessed at; documenting who collected the specimen and when preserves the chain of custody the lab needs to trust the result.
Non-Sterile Dressings and Elastic Stockings
Within a nurse aide's scope, you may apply a non-sterile dressing to a clean, dry, intact wound edge, such as replacing a simple gauze cover that a nurse has already assessed, and you may apply elastic stockings (TED hose), which reduce the risk of blood clots by promoting venous return in the legs. TED hose should be applied while the resident is lying down, before the legs swell from sitting or standing, smoothed to avoid wrinkles or bunching (which can create a tourniquet effect and cut off circulation), and removed and reapplied on the facility's schedule so the skin underneath can be checked.
What Is Outside a Nurse Aide's Scope
The NNAAP exam frequently tests the boundary of nurse aide practice, and questions often describe a task that sounds simple but is legally restricted to licensed staff. A nurse aide cannot:
- Insert, remove, or irrigate a urinary catheter
- Give injections of any kind, including insulin
- Insert a feeding tube or administer tube feedings that require clinical judgment beyond what is delegated
- Change a sterile dressing or perform wound care requiring sterile technique
- Administer medications of any kind, with rare state-specific delegated exceptions that are not assumed on this exam
- Perform venipuncture (drawing blood) unless specifically certified and delegated to do so in that role
Exam trap: a scenario may show a resident asking the nurse aide to just hand over pills from the medication cart, or to put in a new catheter since the nurse is busy. The correct answer is always to decline the task and notify the nurse, because these tasks are outside the nurse aide's legal scope of practice regardless of how simple or urgent the request seems.
Why is the initial flow of urine not included in a clean-catch midstream specimen?
Which of the following tasks are OUTSIDE a nurse aide's scope of practice? (Select all that apply)
Select all that apply
A 24-hour urine collection begins at 7:00 a.m. when the resident voids. What should the nurse aide do with that first voided specimen?
A resident who normally takes oral medication independently asks the nurse aide to hand over pills from the medication cart since the nurse is busy. What should the nurse aide do?