Laboratory - Sampling Flashcards
Why do we carry out an FNA?
- To examine cutaneous masses.
- Assess cell morphology.
- Allows examination of any part of the body (including abdomen, thorax and joints).
What is the patient preparation for FNAs? In terms of positioning and chemical restraint.
- Generally done conscious and well tolerated.
- Positioning will depend on location of the lump.
What sized needle would you use for an FNA?
- 21G-25G.
If you had a sample of pleural fluids, where is this from?
- The pleural cavity lining the lungs.
If you had a sample of peritoneal fluids, where would this be from?
- The abdomen.
If you had a sample of synovial fluids, where is this from?
- The joints.
If you had a sample of cerebrospinal fluids, where is this from?
- The spinal cord.
What components make up a transudate?
- A fluid with LOW PROTEINS and LOW WBCs. Moved out of capillaries due to abnormality in pressure. E.g congestive heart failure.
What is an exudate?
- During the inflammation process (i.e wounds, fluid leaks out - capillaries dilate). Lots of protein and WBCs!
- Can lead to infection and deterioration of wound.
What is a modified transudate?
- Moderate level of protein and WBCs. Fluid build up. Can turn into exudate over time.
what is an effusion?
- An abnormal accumulation of fluid in the body/body cavities discussed earlier.
What might cause an effusion?
- If there’s inflammation it causes an increased volume of fluid.
If the effusion is red what might this mean?
- Blood, signifies trauma or inflammation.
What might it mean if the effusion was a white/cloudy colour?
- WBCs and proteins present. Infection or inflammation.
What is the difference between the turbidity of a normal and abnormal fluid/effusion?
- Normal = not cloudy, clear.
- Abnormal = Cloudy (WBC and protein build up).
What is the specific gravity?
- The density related to water.
What does a higher specific gravity of this fluid signify?
- More WBCs and proteins present. Potential infection.
What is an arthrocentesis?
- The collection of synovial fluid from the joints.
What issues does collecting this sample investigate?
- Synovitis, lameness and arthritis.
Does arthocentesis require flexion or extension of the joint and why?
- Flexion to create better access to the joint cavity.
What containers are suitable to put the synovial fluid into?
- Plain tube or EDTA tube.
What equipment is needed to carry out an arthrocentesis?
- Sample container, generally EDTA
- Needle & syringe
- Clippers
- Chlorhexadine
- Pen to label.
Why might you take a cerebrospinal fluid sample?
- Collected from a neurological patient or prior to myelography for imagine a spinal cord for possible trauma or neoplasia.
What are the 2 methods in which you can acquire this sample?
- Suboccipital puncture.
- Lumbar puncture.
Why do we carry out a thoracocentesis?
- To remove air or fluid directly from the thoracic cavity.
What 2 ways can we carry this out in terms of chemical restraint?
- GA
- Conscious with local anaesthetic.
If there is a pleural effusion, what are 2 things we might need to do?
- Chest drain if lots of fluid to continually drain/
- If emergency for sampling, butterfly catheter.
What is the technique for this?
- Clip & surgically prep area.
- Local anaesthetic administered s/c.
- Insert drain or catheter into the ventral 3rd of the intercostal space between 7th & 8th rib.
- For draining fluid - small incision is made with a scalpel and an “over the needle” catheter is used with a 3 way tap connection to avoid causing a pneumothorax.
Where are you removing fluid from for a pericardial-centesis?
- The pericardium (the membrane surrounding the heart).
What is an accumulation of fluid in the abdomen known as?
- Ascites
Why might this build up be there?
- Trauma
- Viral conditions
- Heart or liver disease.
- Infection.
- Tumours.
- Can happen from congestive heart failure.
Why might you carry out a tracheal wash or bronchoscopy?
- To investigate;
- Chronic coughing
- Suspected bacterial or fungal infections.
- Parasites (lungworm).
- Antibiotic sensitivity.
What equipment do you need to obtain a cerebral spinal fluid sample?
- specialised spinal needle.
- collection tube
- sterile gloves
- sterile drape for equipment
- sterile equipment.
What are the complications of doing a chest drain/catheter for pleural effusions?
- Could puncture a lung.
- Could introduce air via 3 way tap (pneumothorax).
- Haemothorax.
What machinery should you use to monitor during a pericardial-cenesis and what are you monitoring for?
- ECG.
- Can get arrhythmias during this procedure.
What position should the patient be in for a pericardial-centesis?
- Left lateral.
If you think you have punctured the heart during a pericardial-centesis, what should you do?
- Check the clotting. Blood will clot but fluid won’t.
Why is it good to try and do a tracheal wash with a endoscope?
- so you can see the damage/trauma.
How much sterile saline should you flush with for both a tracheal wash and a bronchoscopy?
- Tracheal - 4-6mls
- Bronchoscopy - 10-20mls.
What are the 3 different types of tissue biopsy techniques?
- Punch.
- Wedge.
- Tru-cut.
What is the difference between a punch biopsy and a wedge biopsy?
- Punch, use a little device to punch a hole/chunk out.
- Wedge - Use a blade and manually take a wedge out.
What is a tru-cut biopsy and what do you need for it?
- A special needle, looks like a pair of scissors and it’s spring loaded. Takes a slither of tissue. Less trauma.
What are tru-cut biopsies used for. Skin or organs?
- Organs.
What is the intracapsular technique for obtaining a solid biopsy sample?
- Remove mass along with the capsule it’s contained in.
What is the marginal technique for obtaining a solid biopsy sample?
- Describes the area around the mass.
What is the wide technique for obtaining a solid biopsy sample?
- Large amount of healthy tissue around the mass.
What is the radical technique for obtaining a solid biopsy sample?
- Margin close to the mass.
What is the wedge technique for obtaining a solid biopsy sample?
- Take a full thickness slice of the tissue with scalpel blade.
