Medicine Flashcards
List the 4 syndromes of visceral pain.
- Distension
- Ischaemia
- Mesenteric tension
- Increased intraluminal pressure in hollow viscera
What are the common causes of chest pain?
Usually parietal pleural.
- pleuritis
- pleuropneumonia
- pneumonia
- lung abscess
What are the possible causes of headshaking?
- Trigeminal neuralgia
2. Photophobia
Define hyperthermia.
Significant increase in body temperature where the core body temperature set point is unaltered.
Define fever.
Significant increase in temperature where temperature set point is elevated.
List some causes of hypothermia.
- Accidental eg. cold damp environment, surgery
2. Pathological eg. sepsis, shock, intracranial disease, hypothyroidism
Describe possible treatment options for a headshaking horse.
- Trigeminal neurectomy (?)
- Caudal compression of infraorbital nerve
- Avoidance of stimuli eg. tinted contact lenses, face masks/hoods/nets
- Cyproheptadine +/- carbamazine (together may have short effect and cause drowsiness)
- Permanent tracheostomy- avoids stimulating airflow in nasal cavity
What empirical antibiotics should be used to treat neonatal pneumonia?
Cephalosporin
What are the potential sequelae to fractured ribs in the foal?
Haemothorax
Pneumothorax
Lacerated lung/pericardium/myocardium/diaphragm
List the differentials for neonatal respiratory disease.
Pneumonia Fractured ribs Aspirated meconium Prepartum EHV-1 infection Inadequate lung maturation
Outline the pathology and clinical signs of Rhodococcus equi infection in the growing foal.
Multifocal pulmonary abscessation +/- abscessation in other organs e.g. GIT. Clinical signs: -debility -ill thrift -progressive dyspnoea -immune-mediated polysynovitis
How might you treat Rhodococcus equi infection in the foal?
A/bs: macrolide (erythromycin) + rifampin
How can you prevent Rhodococcus equi infection in a group of growing foals?
- Improve husbandry e.g. reduce stocking density, prevent dusty areas, rotate paddocks
- Administer appropriate prophylactic antibiotics
- Administer specific hyperimmune serum
List the clinical signs of strangles.
Dysphagia Bilateral purulent nasal discharge Lymphadenopathy (submandib/submax/pharyngeal) Extended neck Dyspnoea
Define ‘bastard strangles’.
Abscessation in other tissues besides usual LNs- including mediastinal + mesenteric LNs, joints. Dramatic weight loss and pyrexia occurs.
List the potential sequelae following a strangles infection.
Bastard strangles
Purpura haemorrhagica
Guttural pouch emphysema
What is the aetiological agent of strangles?
Streptococcus equi var equi
What disease does EHV-1 cause?
Reproductive disease (abortion) and encephalomyelopathy
What disease does EHV-2 cause?
Respiratory disease
What causes recurrent airway obstruction (RAO)?
Airway inflammatory response to organic dust particles (endotoxins, moulds, particulates) inhaled from poorly conserved hay/straw
List the clinical signs of recurrent airway obstruction (RAO).
Bilateral mucopurulent nasal discharge
Coughing (!!!)
Heave line
Audible wheezes/crackles
How is recurrent airway obstruction (RAO) treated?
- Turn out or house in dust-free enviro e.g. shavings/paper bedding, haylage/chopped dred alfalfa/cubed diet, ventilation
- Bronchodilators e.g. atropine
- Prednisolone
- Maintain hydration
What causes summer pasture associated obstructive pulmonary disease (SPAOD)?
Affects pastured horses with NO access to hay/straw in the Spring-Autumn. May be hypersensitivity to inhaled polens or outdoor moulds?
Where does bleeding originate from in exercise-induced pulmonary haemorrhage (EIPH)?
Dorsocaudal lung
On bronchoscopy of a horse with EIPH, what might you expect to find post-exercise at:
i) 30 minutes
ii) few days
iii) week
iv) What would you find on BALF/tracheal aspirates after a few months?
i) Fresh blood in trachea
ii) Blood in large bronchi
iii) Haemosiderin tinged secretions
iv) Macrophages containing haemosiderin
List the clinical signs of pulmonary abscesses/pleuropneumonia.
Pyrexia Anorexia Ventral oedema Pleural pain Lethargy
What parasite causes lungworm infestation in horses?
Dictyocaulus arnfieldi
List the causes of poor performance in the athletic horse.
- Musculoskeletal
- Respiratory
- Lack of fitness
- Unrealistic expectations (of horse/rider)
- Inappropriate training
- Cardiovascular
- Other e.g. medical, neuro
Describe the features of atrial fibrillation i) on auscultation and ii) on ECG.
i) irregular rhythm with LOUD 3rd heart sound and NO 4th heart sound, may be tachycardic if secondary to mitral regurgitation
ii) irregularly irregular rhythm with no p-waves and atrial fluttering- ‘f-waves’
Describe the treatment options for atrial fibrillation.
DO NOT TREAT if: only diagnosed 2-3 days ago (may spontaneously resolve), no effect on exercise or if there is evidence of heart failure.
- Quinidine sulphate via nasogastric tube every 2 hours (beware toxicity).
- Electric defibrillation via direct shock under GA
Describe the ECG features of i) premature atrial beats, ii) premature ventricular contraction and iii) 3rd degree AV block.
i) abnormal p-wave shape, early p-wave and QRS complexes
ii) no p-wave with wide bizarre QRS complexes
iii) multiple p-waves with no QRS complexes
List the causes of pericardial effusion.
Idiopathic fibrinous/effusive pericarditis
Neoplasia
Traumatic H+
Septic disease
List the causes of cardiac murmurs.
Acquired valvular: mitral regurgitation, tricuspid regurgitation, aortic insufficiency
Congenital: ventricular septal defect
Which pathology produces a pansystolic murmur loudest over the 5th intercostal space?
Mitral regurgitation
Which pathology produces a soft grade 2-3 pansystolic murmur loudest on the RHS?
Tricuspid regurgitation
Which pathology produces a diastolic musical murmur loudest over the 5th LHS intercostal space?
Aortic insufficiency
Describe the aetiology of tricuspid regurgitation.
LV failure -> pulmonary hypertension -> RV overload
Describe the aetiology of aortic insufficiency.
Progressive thickening and fibrosis of valve leaflets in older (>10yo) horses.
List the potential causes of mitral regurgitation.
Ruptured chordae tendinae
Any condition causing dilation of valve annulus e.g. DCM, aortic insufficiency, VSD
Congenital malformation of valve
Infective endocarditis
Eccentric hypertrophy and increased blood volume
Degenerative thickening of the valve leaflets.
List the causes of icterus.
Regurgitation icterus: reduced excretion of bilirubin with liver of biliary tract disease
Haemolytic/prehepatic icterus: increased production of bilirubin with haemolytic anaemia
Hepatic icterus: reduced conjugation or hepatic uptake of bilirubin with liver disease
List the methods which can be used to determine the cause of icterus.
- Relative amounts of conjugated vs. unconjugated bilirubin
e. g. >25% conjugated = heptaocellular disease, >30% conjugated = cholestasis - Liver-derived enzymes- to assess if assoc w/ liver damage
- Bile acids- to assess if assoc w/ liver failure
- PCV + RBCC- to assess if assoc w/ haemolysis
What is the likely cause of icterus with increased unconjugated bilirubin in the serum and reduced PCV?
Haemolysis
What is the likely cause of icterus with increased unconjugated bilirubin in the serum, normal PCV and liver enzymes?
Anorexia
What is the likely cause of icterus with increased unconjugated and conjugated bilirubin in the serum and rincreased liver enzymes and bile acids?
Liver disease
Which liver-derived enzymes are specific to hepatocytes?
GLDH (spec), AST
Which liver-derived enzymes are specific to the biliary tract?
GGT (spec), AP
What are the clinical signs of equine liver disease?
Icterus
Photosensitisation
Severe pruritus
Hepatic encephalopathy -> neuro signs e.g. dull vacant expression, yawning, ataxia, tremors, circling, head pressing, aggression
Bilateral laryngeal paralysis -> dyspnoea, stridor at rest
Petechiae
Coagulopathy
Describe how you would treat hepatic encephalopathy.
Sedate with low dose alpha-2 agonists
Correct metabolic, fluid and electrolyte abnormalities
Reduce GIT production/absorption of potential neurotoxins through laxative and oral neomycin/metronidazole
Lactulose- reduce intestinal neurotransmitter production/absorption
What would a negative response on the thoracolaryngeal reflex suggest?
Possibly recurrent laryngeal neuropathy
Describe where you would perform a CSF tap in horses.
- Atlantooccipital (AO)
- Lumbosacral
Always tap closest to the lesion!
What is the most common cause of equine brain disease in the UK?
Hepatic encephalopathy
What is the causative agent of leukoencephalomalacia?
Fusarium species mycotoxicosis from mouldy feed.
What is the cause of polyneuritis equii?
Chronic granulomatous inflammation of extradural nerve roots of many peripheral nerves.
What are the clinical signs of polyneuritis equii?
Cranial nerve deficits (VII/VIII first)- progressive
What is the cause of temperohyoid osteoarthropathy?
Proliferative osteopathy of unknown cayse of temporal and hyoid bone and temperohyoid joint. Tongue movement can fracture the temporal or stylohyoid bone which damages facial and vestibulocochlear nerves.
What are the clinical signs of temperohyoid osteoarthropathy?
Vestibular/facial nerve signs
Head shaking
Dysphagia
Which cranial nerves are most commonly affected by guttural pouch mycosis?
7, 8-sympathetic, 9, 10, 12