ClotPro testing clarifies clotting in 84 hospitalized dogs

By Elena Vasquez

A retrospective study of 84 client-owned dogs found that ClotPro measurements broadly corresponded with conventional coagulation results and captured patient-specific differences in clot formation, strength, and breakdown, but the test did not reliably identify disease or predict thrombosis.

What did the study test?

The Journal of Veterinary Internal Medicine published “ClotPro viscoelastic testing in coagulation disorders in dogs: a retrospective analysis” on October 9, 2026, in Volume 40, Issue 5. The full article is open access.

Authors Pavlos G. Doulidis, Carolina Frizzo-Ramos, Larissa J. Prankch, Barbara Rütgen, Iwan A. Burgener, and Nicole Luckschander-Zeller conducted the work at the University of Veterinary Medicine Vienna in Austria.

The study evaluated 84 client-owned dogs with naturally occurring diseases, all hospitalized. Conditions included acute hemorrhagic diarrhea syndrome, liver disease, thrombocytopenia, immune-mediated hemolytic anemia, protein-losing nephropathy, protein-losing enteropathy, hyperadrenocorticism, thrombosis, and other disorders associated with coagulation abnormalities.

Researchers compared ClotPro with prothrombin time (PT), activated partial thromboplastin time (aPTT), platelet counts, and D-dimer concentrations. Conventional tests assess selected coagulation-cascade components; ClotPro uses whole blood to track clot initiation, strength, and fibrinolysis, the breakdown of a formed clot.

Takeaway: The study tested whether a broader coagulation profile adds useful information, not whether ClotPro-guided treatment improves survival.

What did ClotPro reveal?

Clotting time from the extrinsic-pathway channel had a moderate positive correlation with PT, while intrinsic-pathway clotting time correlated with aPTT. Those relationships indicate that the system captured biologically meaningful information from the same pathways assessed by conventional laboratory testing.

Higher platelet counts tended to accompany greater maximum clot firmness. The fibrinogen contribution to clot formation also correlated with overall firmness, supporting roles for both platelets and fibrin in clot stability.

ClotPro also used an aprotinin-based channel to help separate true fibrinolysis from other changes in clot firmness. Greater clot breakdown accompanied reduced firmness, and higher D-dimer concentrations had a modest association with increased fibrinolysis.

Although excessive fibrinolysis was uncommon overall, it appeared in approximately 33% of dogs with liver disease and 21% of dogs with acute hemorrhagic diarrhea syndrome that had sufficient test data. The group sizes were small, so the percentages require caution and cannot define routine screening rules.

Takeaway: ClotPro can show how an individual dog forms and breaks down clots now; it does not supply a universal bleeding or clotting rule.

Can ClotPro identify a disease or predict thrombosis?

Some expected disease patterns emerged. Immune-mediated hemolytic anemia, protein-losing enteropathy, protein-losing nephropathy, and hyperadrenocorticism can carry increased thrombotic risk in some patients, while thrombocytopenia and severe bleeding disorders can accompany reduced clot strength or delayed clot formation.

The overlap proved decisive.

The groups did not separate reliably. Two dogs with the same diagnosis could have substantially different coagulation profiles, while dogs with different diseases could show similar abnormalities.

A composite hypercoagulability index, built from clotting speed and clot strength, differed significantly across disease groups and may characterize a tendency toward increased clot formation. A second index accounting for platelet and fibrinogen contributions did not differ significantly between diseases.

An abnormal coagulation pattern therefore did not reliably reveal its cause or establish that a dog would develop a thrombotic event. ClotPro characterizes current hemostatic state, but the study does not support it as a stand-alone diagnostic test for a particular disease.

Takeaway: An abnormal coagulation profile can exist without revealing its cause, and abnormality does not mean thrombosis will follow.

What changes at the exam table?

For emergency and critical-care teams, the findings support ClotPro as a complement to conventional diagnostics in dogs with complex coagulation disorders. Critically ill patients can have rapidly changing abnormalities involving several mechanisms; reading clot formation, strength, and fibrinolysis together may give a fuller picture than PT, aPTT, and platelet counts alone.

The platform may also help track changes over time in patients with bleeding or thrombotic disease. That monitoring use remains plausible rather than proven, because the study did not measure actual thrombotic events, transfusion requirements, bleeding complications, survival, or whether treatment guided by ClotPro reduced complications.

The evidence also carries clear limits. The retrospective design, small sample, and sparse numbers in some disease categories restrict generalization. Not every dog had complete results from every channel, particularly those used to assess fibrinolysis. Thresholds for hypercoagulability came from this population rather than established canine diagnostic reference intervals.

Hematocrit, platelet count, sample handling, and inflammatory status may independently alter viscoelastic measurements. Clinicians should therefore interpret ClotPro alongside a complete blood count, conventional coagulation results, and the patient's clinical condition rather than treating a channel as a diagnosis.

Takeaway: Use ClotPro to add context to standard testing and serial assessment, not to replace either or make a stand-alone thrombotic-risk call.

Which species and public-health settings can use these findings?

• Companion animals: The findings apply directly to hospitalized dogs and support considering ClotPro alongside conventional testing in complex cases, within the study's limits.
• Food animals: The study included no cattle, pigs, or other food-producing species and therefore establishes no testing recommendation for food animals.
• Public health: The report did not assess zoonotic transmission, population-level risk, or public-health interventions, so it supports no public-health conclusion.

Takeaway: The actionable evidence applies to dogs; it does not transfer to food animals or public-health programs without separate studies.

What needs to happen next?

Prospective canine studies should establish usable reference intervals, address incomplete fibrinolysis data, and test whether ClotPro-guided decisions reduce bleeding, transfusion requirements, thrombotic events, or complications and improve survival. Until then, the open-access analysis provides performance data rather than a treatment algorithm.

Takeaway: The next evidentiary step is to determine whether better coagulation characterization translates into better patient outcomes.