Diagnostic test and Specimen collection

posted Feb 6, 2012, 8:39 PM by Huong-Giang Pham   [ updated Feb 6, 2012, 9:09 PM ]
- Diagnosis: to verify alterations identified in the nursing health history and physical examination.
- Establish baseline: to provide information about the illness, the effect of treatment and progression of disease
- Screening: to identify actual or potential health care problems and risk of disease (early detection)

Nursing responsibilities

Health teaching

- Explain the procedure, the purpose, the preparation and restrictions to patient and family
- Explain sequencing of procedure
- Answer questions
- Explain any side effects
- Teach relaxation techniques
- Explain what will happen after the procedure

Preparing patient
- Physically prepare patient. For example: enemas, NPO, full bladder
- Use proper collection equipment
- Keep patient NPO
- Follow proper procedure according to specific agency
- Use Universal precautions to ensure no contact with body fluids
- Ensure patient has proper ID band
- Administer medications, including analgesics prn
- May require transfer to another agency for the procedure

- Communicate to other health care professionals that affect procedure. Eg: allergies to shellfish, physical limitations...
- Documentation:
    + Label specimen appropriately with patient name, ID number, date, source of specimen
    + Document patient teaching, patient response and the procedure on patient chart

Assisting with procedure
Nurse's role
- Use standard (universal) precautions
- Position patient in correct position
- Use proper equipment for specimen collection
- Handle sterile equipment properly: do not touch inside, turn cap upside down on table and recap promptly to avoid contamination
- Provide emotional support for the patient
- Send specimen to lab in Biohazard bag
- Explain what patient can expect post-procedure, eg. no intercourse... it is particular for every agency.

After test
Patient safety:
1. Primary responsibility is to assess the client
- Airway
- Vital signs
- Comfort and warmth
- Pain relieve
- Emotional support
- Post test restrictions, e.g. diet, positioning

2. Responsibility to ensure proper technique

Specimen collection
- Correctly labeled
- Correctly handled using Standard (universal) precautions
- Correctly stored: refrigerated, on ice, specimen to lab stat
- Correct documentation
- Correct disposal of equipment

Policies and procedures
- Describe the role of the nurse and other health care providers
- Provide important information about patient teaching/education
- Provide essential information about patient care before, during and after procedure
- Describe correct handling of specimens
- Each institution may follow different procedures

- Universal precautions should be used for all specimen collection
- Specimens are placed in a sealed plastic bag before sending to lab
- Labeled properly

Urine tests
- Easy to obtain and provides valuable information about many body system functions
    + Kidney function
    + Glucose metabolism
    + Various hormone levels
- Assess patient's ability to produce specimen appropriately

Routine and Microbiology (R&M)
- Use first morning specimen, it is more concentrated
- Need clean test tube
- Random urine specimen can be collected anytime

To find more information about urine tests and related medical diagnosis, click here

Culture and sensitivity (C&S)
- Proper midstream collection in sterile container
- Culture: grow in petri dish in lab to determine causative organism
- Sensitivity: apply medication discs to determine which medication is effective
- Can be obtained by catheterization from indwelling urinary catheter aslo
- Refrigerate specimen

24-Hour urine specimen
- Discard the first specimen and record the time
- Use proper gallon container with preservative and keep on ice or in refrigerator
- No stool or toilet paper in specimen
- Exactly 24 hours later, have patient void and send specimen to lab with proper label

- Examination of feces provides important information that aids in differential diagnosis of various gastrointestinal disorders
- Fecal studies may also be used for microbiologic studies, chemical determinations and parasitic examinations

- Clean container
- No urine or toilet paper in specimen
- Some collections (occult blood) require dietary restrictions before collection (red meat, no iron meds, certain vegetables)
- Some stool specimens must be taken to lab within 30 minutes of collection
- Some specimens are repeated. e.g. 3 days
- Some are obtained with tongue depressor and smeared on medium
- Others are collected in sterile container

Tests done: C & S, Occult blood, Ova and parasites

- Specially trained personnel for venipuncture and arterial collection
- Practical nurse can perform finger/heel prick
- Is fasting required e.g blood sugar, cholesterol
- Are routine medications identified on label?
- Has time and date been recorded?

Arterial blood gases:
- Drawn from artery full with oxygen
- Keep on ice, get right to lab
- High risk of bacterial
- Get protected

- Useful for diagnosing microorganisms causing respiration infection and for detecting malignant
- Ensure sample is sputum and not saliva
- Always C&S specimen that is refrigerated

Tests done: C&S, ACID-FAST BACILLI (AFB) (determine presence of Mycobacterium tuberculosis), Cytology (examination of slough cells for cancer diagnosis)

- Throat, cheek, nose
- Peri-anal, rectal, vaginal
- Wounds: clean with NS (normal saline) first
- Some agencies moisten swab with normal saline
- Always sterile C&S specimen
- Collection test tube with medium

Assessing result
- Abnormal values: outside the normal range for that particular test
- Normal blood sugar: 3.5 - 6.1 mmol/L
- Abnormal blood sugar 6.5 mmol/L

What is the clinical significance of results?

Critical lab values
- If left untreated, could be life threatening or place the patient at serious risk
- Critical results need to be communicated immediately to physician
- Notifying doctor is often nursing role

Invasive vs. Noninvasive
- Invasive: involve puncture, incision, or insertion of a foreign object into the body e.g needle, probe, IV
- Noninvasive: a device or procedure that does not penetrate the skin or enter any orifice in the body E.g X-ray, ultrasound, CT scan

Routine admission test
- Complete blood count (CBC): Red blood cell count (RBC), hemoglobin (Hb, Hgb), Hematocrit (Hct)
- White blood count (WBC) or leukocytes
- Glucose
- Electrolytes
- Urinalysis
- Blood urea nitrogen (BUN)
- Creatinine

Huong-Giang Pham,
Feb 6, 2012, 9:07 PM
Huong-Giang Pham,
Feb 6, 2012, 9:07 PM