It is very important to differentiate between postmortem clots and venous thrombi during the autopsy. Both Venous Thrombi and postmortem clots form casts of the lumen of veins.
Following are the distinguishing points.
- Venous thrombi are firm while postmortem clots are rubbery and gelatinous
- Venous Thrombi are a rich admixture of RBCs and appear red, while postmortem clots appear as dark red independent portions because in the dependent portion of vessel RBC aggregate and the supernatant portions are free of RBCs and appear as yellow chicken fat.
- Another main difference is that venous thrombi are attached to the vessel wall while postmortem clots are not.