nchsls:c:cytopathology:document:08

Procedure for primary sample collection & handling

NameUnique ID Edition/Date of Edition
Procedure for primary sample collection & handling nchsls:c:Cytopathology:document:08 03-01-2015
Preparing authorityApproving authorityReview period
All teaching staffIn-charge Cytopathology1 year
Controlled copy of this document exists only in electronic form at IP address 10.207.3.241 of LAN at NCH, Surat
Printed copy of this document with signature of authorized person is to be considered controlled.

1. Completion of request form

2. Preparation of the patient for sampling:

  1. A clear explanation of the procedure.
  2. Explain procedure and possible side effects.
  3. Take informed consent
  4. The procedure is carried out in supine position on a simple examination couch or a chair with head rest for aspiration from head & neck area.
  5. Local Anesthesia is given by clinician in deep seated lesion are to be aspirated with aid of CT or USG

3. Primary sample collection:

Preparation of FNA- Equipment
  • Standard Disposable
    • Needle – 22/24 gauge, 30-50 mm long
    • Syringe – 10-20 ml.
    • Small containers with lid.
    • Glass slides.
    • Fixatives- 70-90% ethanol in Copline Jar.
  • 22 gauges, 90 mm disposable lumber puncture needle with trocar are convenient for most aspiration in deep seated sites.
Procedure:
  • To increase the yield, the needle should be moved back & forth with negative pressure. In very vascular tumors in thyroid, bone, kidney, FNA without aspiration is recommended to prevent admixture with blood.
  • After aspiration of superficial lesions pressure should be applied over the aspiration site to minimize bruising and to decrease the chance of hematoma.
  • The sample contained in the needle is expelled on a clean and dry microscopy slide using air in the syringe.
  • The aspirate is smeared with the edge of a microscopy slide exerting a light pressure to achieve a thin even spread. (Too much pressure produce artifact. This should be done before coagulation occurs otherwise cells and tissue particles present in the clot and will not spread adequate on slide.
Fixation:
  • Those slides to be stained with MGG stain - Air dried
  • Those slides to be stained with H& E and PAP stain -Alcohol fixed (wet fixed)
Fixatives:
  • 100% Methanol
  • 95 % Ethanol
  • 95% Denatured alcohol
  • 80% Propanol
  • 80% isopropanol
Pleural fluid Aspiration
  • Pre- anaesthetic medication- Inj. Atropine 0.6 mg
  • Position – Patient sites up against a backrest.
  • Site- 7th or 8th ICS in midaxillary or scapular line
  • Clean the site with catavlon, ether, iodine & spirit.
  • Local anaesthetic- skin, subcutaneous tissue & parietal pleura are infiltrated with 2 % lignocaine.
  • Puncture – introduce the aspiration needle at right angles to the skin, mid way between two ribs, till

the parietal pleura gives in, the needle is then attached to a 50 ml syringe & fluid is aspirated.

  • Seal- The site is sealed with tincture benzoin seal.

Note: Specimen should be transported as early as possible at room temp. (As to prevent disintegration of cells)

Preservation of Material
  • If specimen is to be submitted for immediate processing, no fixative is needed.
  • Sputum- If refrigerated can be preserved for 12-24 hrs.
  • Specimen with high protein content eg. Pleural, peritoneal & pericardial may be preserved for 24-48 hrs without refrigeration.
  • Urine & CSF will endure only 1-2 hrs delay (or then color be protein content) will be refrigerated.
  • Specimen with low PH like gastric material must be collected and prepared with in minute of collection.
For Sputum collection
  • Early morning sample is collected.
  • Patient should be instructed that, the diagnostic material comes from deep within the lungs.
  • They should be asked to clear their nasal passages and rinse their mouth with water, discarding that material before collecting a specimen.
  • Ideal diagnostic material is obtained from a spontaneous deep cough, which should be expelled in a wide mouth container with screw cap with fixative
Sample collection & Labeling
  • Please mention Patient Name, Test, Date and Type of sample on the tube.
  • Sample collection should be as mentioned.
  • Unlabelled samples will not be processed.
Type of sampleCollected in
PAP Smear100% Methanol for 30 minute
FluidsEDTA vacutainer
Note: Urine: Collect mid stream urine in plain container. CSF: Collect CSF in EDTA vacutainer after releasing cap and removing vacuum. Body Fluids: Collect Body fluids in EDTA vacutainer after releasing cap and removing vacuum.

5.Availability of clinical advice on ordering of examinations and on interpretation of examination results.

  • Specimen of fluid should be submitted to the laboratory as early as possible within 2 hours of collection.
  • Patient selection:In patient with clotting disorders deep seated lesions should not be aspirated.
  • While taking Pap smear
    • Women should not use any vaginal medication, contraceptives during the 48 hours prior to the sample collection.
    • Mucous or any other discharge from the cervix should be gently removed by a folded gauze pad.
    • The cervix should not be cleaned by washing with saline as it may result in a relatively acellular sample.
    • Wet smears should immediately be fixed without delay
Contraindications of FNAC
  • Carotid body tumors
  • Pheochromocytomas
  • Highly vascular tumors
  • Hemangiomas
  • Prostatitis
  • Ovarian cyst aspiration
  • Hydatid cysts
  • Lung lesions like severe emphysema, pulmonary hypertension-condition associated with severe hypoxemia.
nchsls/c/cytopathology/document/08.txt · Last modified: 2022/08/13 07:34 (external edit)