PATHOLOGY - Post Mortem Flashcards
Why do you carry out a post mortem?
- Identify cause of death
- Collect evidence as part of a legal investigation
- Collect tissue or other materials for a herd health investigaton or research
What are the two orientations that can be used to carry out a post mortem?
Dorsal recumbancy post mortem
Left lateral recumbancy post mortem
What are the sixteen steps to a dorsal recumbancy post mortem?
- External examination
- Stabilise carcass through cutting axillae and hip joints to reflect limbs
- Midline incision from mandible to pelvis and reflect to skin
- Examine exposed peripheral lymph nodes
- Expose oral cavity, tongue and continue with larynx and trachea to thoracic inlet
- Examine the thyroids and parathyroids
- Reflect abdominal wall with midline incision
- Examine abdominal cavity
- Examine diaphragm and pierce
- Open thoracic cavity
- Remove internal organs
- Evaluate individual organs, section appropriately and collect samples
- Collect bone marrow from femur
- Open joints
- Collect brain if requested
- Collect spinal cord if requested
In the dorsal recumbency approach, after you have reflected the skin from the neck, thorax and abdomen, which superficial lymph nodes can you examine?
Prescapular lymph nodes
Superficial inguinal lymph nodes
Submandibular lymph nodes
Axillary lymph nodes
What are the thirteen steps to a left lateral recumbancy post mortem?
- External examination
- Stabilise carcass through reflecting the right forelimb and both hindlimbs
- Midline incision from mandible to pelvis and reflect to skin
- Examine exposed peripheral lymph nodes
- Expose abdominal cavity by reflecting abdominal wall ventrally
- Check diaphragm and pierce
- Open thoracic cavity
- Remove abdominal organs and pluck (tongue to thoracic organs) seperately
- Evaluate individual organs, section appropriately and collect samples
- Collect bone marrow from femur
- Open joints
- Collect brain if requested
- Collect spinal cord if requested
What should you check during the external examination?
ID
Age
Breed
Sex
Body condition score
Weight
Abnormalities of the hair and skin
Physical injuries or ectoparasites
Discharges, exudates and mucosal features
Why is it so important to pierce the diaphragm before opening the thoracic cavity?
This allows you to assess the negative pressure within the thorax
What are the five types of sample you can take from a post mortem?
Histopathology
Bacteriology
Virology
Toxicology
Parasitology
What should you include on the submission form for a postmortem sample?
Complete history
Patient name
Age
Species/breed
Sex
Type of sample
Test required
What information should you include on the sample label?
Patient name
Data collected
Type of sample
What are the recommended dimensions for a histopathology tissue sample?
Tissue for histopathology should be less than 1cm in at least one dimension
Why should a tissue sample for histopathology be placed in formalin immediately after collection?
Formalin preserves the tissue and fixes the tissue in an as life like state as possible
What percentage of fomalin is preferred for preserving tissue for histopathology?
10% formalin
When fixing tissue for histopathology, what is the recommended ratio of formalin to tissue?
10 parts formalin to 1 part tissue
How long should tissue samples for histopathology be fixed in formalin before being processed in the laboratory?
24 hours
How should be prepare a sample of intestine for bacteriology and virology?
Collect a sample of intestine and tie off each end of the sample about 2-3 inches apart
