Knowledge Base › Troubleshooting Atlas › Cytology preparation
Smears too thick / obscured by blood
Also known as: thick smears, bloody smears
What it looks like
The slide shows a thick layer of cells with significant blood obscuring the cellular details.
Where it usually appears: Typically seen in samples from highly vascularized tissues or in cases of hemorrhage.
Likely causes
- Excessive blood in the sample
- Improper fixation technique
- Inadequate spreading during preparation
Immediate checks
- Evaluate the sample for blood content
- Assess the spreading technique used
Corrective action
- Dilute the sample with saline before preparing smears
- Use a different spreading technique to achieve a thinner layer
Preventive action
- Use appropriate anticoagulants if necessary
- Ensure proper collection techniques to minimize blood contamination
This atlas is for educational purposes for laboratory professionals. It does not replace your institutional SOPs, manufacturer instructions, validated protocols or pathologist judgment. Adapt any action to your laboratory and equipment.
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