Pathophysiology Flashcards
What is the modified Bernouli equation?
Change in pressure = 4v2
If a dog has a peak tricuspid regurgitant jet velocity of 1.96 m/s, what is the pulmonary arterial pressure and is the pulmonary arterial pressure normal or abnormal (if abnormal, what severity)?
15 mmHg (normal is <30mmHg)
If a dog has a tricuspid regurgitant jet of 4.3 m/s, what is the pulmonary arterial pressure? Is it normal or abnormal (if abnormal, what is the severity)?
74 mmHg - moderate severity (51-80mmHg)
What are the normal systolic pressures in the heart and great vessels?
Nickel - Dime - Quarter - Dollar
Right atrium - 5
Left atrium - 10
Right ventricle and MPA - 25
Left ventricle and Ao - 100
Cushing’s reflex
Maintenance of intracranial pressure
CPP = MAP - ICP
If MAP drops below ICP –> hypothalamus initiates ischemic reflex –> sympathetic nervous system induces vasoconstriction and increased CO until MAP is restored. Baroreceptors on carotid bodies sense hypertension –> reflex bradycardia
CSF production
Ependymal lining (pia and arachnoid) in ventricles and central canal
Choroid plexus in lateral, third, and fourth ventricles
Produced by ultrafiltration of plasma
T/F: The rate of CSF production depends on osmotic pressure, but not hydrostatic pressure (blood pressure)
True
What is the primary mechanism for CSF resporbtion?
Through the arachnoid villi outpouchings in the dorsal sagittal sinus
What is the most common digital neoplasm in the dog?
SCC
T/F: digital SCC has a worse survival time than digital malignant melanoma
False. The survival time is not dependent on histopathologic type of neoplasia; it is dependent on the tumor stage
Regarding canine digital neoplasia, which prognostic factor is associated with survival time:
- Tumor type
- Presence of metastatic disease
- Local tumor stage
- Age and sex
Only the local tumor stage is associated with survival time
Regarding dogs with appendicular bone neoplasia, which of the following are associated with pathologic fracture?
- Width of the lesion
- Length of cortical involvement
- Age
- Lytic appearance
Lytic appearance
T/F: The radius is associated with a reduced frequency of pathologic fracture due to primary bone neoplasia
True; possibly due to splint effect from the ulna. This was not seen with the tibia/fibula.
Which factors are associated with shorter survival time in urinary bladder TCC?
- Heterogeneous mass
- Trigonal location
- Wall involvement
Telangiectatic osteosarcoma
- Medium dogs
- Aggressive lesion of the tibia
- Shorter survival time than osteogenic osteosarcoma
Is the survival time between telangiectatic osteosarcoma and hemangiosarcoma significantly different?
No. tOSA (7mo) and HSA (10mo)
T/F: Amputation and chemotherapy prolong the survival time in dogs with bone HSA, but not for dogs with bone tOSA
False. Amputation and chemotherapy prolong survival for both
What is the incidence (low, medium, high) for presence of pulmonary metastasis at the time of diagnosis of tOSA? HSA?
High for both
What pathology contributes to degenerative lumbosacral stenosis?
- Hansen type 2 disc degeneration
- Subluxation of the S1 vertebral and misalignment of the facet joints
- Concurrent congenital vertebral anomalies
- Transitional lumbar vertebra
- Supernumerary lumbar vertebra
- Soft tissue and bone proliferation
- Interarcuate ligaments
- Joint capsule
- Epidural fibrosis
- Spondylosis
- Sacral osteochondrosis
- Vascular compromise to the blood supply of spinal nerves
Cats with spinal lymphoma
- Younger at time of diagnosis compared to other tumors
- Shorter duration of clinical signs
- More lesions in the CNS
- Many cats also have extra-CNS disease
Radiographic findings with leptospirosis and pathophysiology
Diffuse or caudodorsal, reticulonodular interstitial pattern
Due to hemorrhage secondary to endothelial damage and vasculitis caused by spirochete replication in the blood vessels
Ultrasonographic findings with leptospirosis
Kidneys
- Cortical and/or medullary hyperechogenicity
- Decreased corticomedullary distinction
- Pyelectasia
- Thickened cortices
- Medullary rim sign
Liver
- Hypoechoic, heptomegaly
Insulinoma metastasis
Metastasize to liver and lymph nodes (high); rarely to bone or lungs
Pathophysiology of insulinoma
Arise from B cells in the islets of Langerhans (endocrine pancreas); neoplastic cells release insulin independent of the normal suppressive effects of hypoglycemia
Medium to large breed, older dogs
Pathophysiology of IMPA
Type 3 hypersensitivity reaction where antigen-antibody immune complexes accumulate in a joint space –> complement activation –> cytokine release –> neutrophils attracted –> neutrophils release cytokines and lysosomal enzymes –> tissue damage
Erosive (rheumatoid) - also has antibody attack against collagen
Non-erosive
What joints are most commonly affected with erosive IMPA?
Stifles and carpi; digits can also be affected
Signalment for erosive IMPA versus idiopathic non-erosive IMPA
Erosive - small breed, middle aged
Idiopathic non-erosive - sporting to large breed, young
8 yo MN DSH presents for several month history of depression and acute blindness. What is your diagnosis (GRE image provided)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/317/707/805/q_image_thumb.png?1595716358)
Pituitary apoplexy - hemorrhagic infarction within a pituitary tumor. Patients usually have acute onset blindness and a history of altered mentation