VetOnIt clinical notes
Five checks for unexpected veterinary laboratory results
Sample additives, lipemia, hemolysis, nucleated red cells and collection problems that can produce unexpected laboratory results, from Dr. Daniel Heinrich’s laboratory diagnostics lecture.
Published · Updated · VetOnIt
1. Check additives and specimen type
Potassium EDTA contamination can falsely increase potassium and lower calcium in a chemistry sample. The collection tube and any opportunity for additive carryover are therefore relevant when interpreting an unexpected electrolyte result. [1] [2]
Potassium released from platelets during clotting can increase serum potassium relative to plasma. In the lecture’s puppy case, the presenter considered both platelet-associated potassium release and EDTA contamination as explanations for the spurious result; neither mechanism was established as the sole cause. [1] [3]
2. Check lipemia and hemolysis
In severe lipemia, the analyzer may count large lipid particles as platelets, falsely increasing the platelet count. A platelet estimate from a blood smear provides a separate check on an unexpectedly high automated count. [1] [4] [5]
Red-cell breakdown after collection can lower the measured hematocrit. The lecture’s lipemic case illustrates a fall in hematocrit caused by progressive hemolysis in the tube while the sample waited for repeat analysis. [1] [4]
3. Check for nucleated red cells
Nucleated red blood cells can be included in a reported white-cell count, making the apparent leukocyte count too high. Blood-smear examination can identify these cells and guide correction of an affected count. The lecture illustrates how this counting problem can mask leukopenia. [1] [6] [5]
4. Check the sampling line
Blood drawn through an intravenous line can be contaminated by residual infused fluid. Potassium-containing fluid can produce a falsely high potassium result. The collection route is therefore relevant when investigating unexpected chemistry results. [1] [7]
5. Check for clotting
Clotting during collection can lower the platelet count even when no clot is seen in the submitted tube. The lecture’s catheter case illustrates why the collection history and clinical findings matter when interpreting an unexpectedly low platelet count. [1] [8]
Related lectures
On-demand lecture
Avoiding Errors in Veterinary Laboratory Diagnostics: Collection to Interpretation
View on-demand lecture →References
- Dr. Daniel Heinrich: Avoiding Errors in Veterinary Laboratory Diagnostics: Collection to Interpretation VetOnIt lecture transcript · January 13, 2026Lecture source retained by VetOnIt.
- Cornell eClinPath: Sample collection for chemistry testing External clinical source
- Cornell eClinPath: Sample collection External clinical source
- Cornell eClinPath: Interferences External clinical source
- Cornell eClinPath: Smear examination External clinical source
- Cornell eClinPath: Nucleated red blood cells External clinical source
- Cornell eClinPath: Potassium External clinical source
- Cornell eClinPath: Sample collection for hematology External clinical source