- Fixative- 60 to 120 seconds; solution 1- 30 to 60, solution 2- 50 to 60 seconds, then gently rinse under cold tap water for 15 seconds
- Impression smears are often best for "oozy" lesions or tissues, for biopsied tissues impression smears should be made with the cut surface of fresh tissue-be sure to BLOT FIRST
- Secondary to trauma, coagulopathy, or any other hemorrhage process (evidence of prior hemorrhage/erythrocyte turnover)- this should NOT be confused with blood contamination which frequently occurs with sample collection
- ALWAYS interpret cytologic findings in the clinical context of your patient and correlate with other findings (history, imaging, presentation, lab data)
- Infectious- bacterial, fungal, protozoal; non-infectious- trauma/irritation, immune-mediated
- non-diagnostic because too thick and poorly stained so cell demarcation is not clear
- Take a wooden stick with material on it and roll it out on slide for at least two lines
- Direct smear- line prep/blood smear, sediment, squash prep, cytospin prep
- Staining protocols can vary depending on the source, but ALL involve successive exposure to three solutions, the thicker the specimen the longer the fixation it will need and stain times, regularly change your stain because old/contaminated stain can result in issues
- Red top to preserve cellular detail and prevent clotting if blood in it, purple top is just to keep some in case you want to do more testing
- UNCOMMON, depend on experience of operator/size of needle/type of lesion aspirated, bleeding so evaluate for bleeding disorders before obtaining an aspirate, tumor needle tract implantation- observe for 12-24 hours after pulmonary aspiration for pneumothorax, may see hypo/hypertension with adrenal mass aspiration
- Put material on one slide and take another slide perpendicular to the other and push away
- Place a drop of fluid on bottom slide, use another slide at an angle to make contact with the fluid and then pull back
- Contact (squash) prep, tissue imprint, camelhair brush- roll rows onto slide
- Put material and take another slide and squash the material and pull up and push down on another part of the bottom slide
- AVOID nicking any vessels or getting just adipose tissues, AVOID getting into any viscera
- Lower magnification (10X) and scan the entire area and then work your way up to a higher magnification
- Make sure the specimen is spread THIN on the slides, air dry the slides, label slides with proper patient information and specimen ID, DO NOT heat fix slides, STAY AWAY from formalin
- Loss of tissue architecture and unable to determine surgical margins, may obtain nondiagnostic samples, limited special stains/follow up techniques on submitted samples
- Some tissues do not exfoliate well like CT so ALWAYS prepare owner that a biopsy follow up may be required