Flashcards in SIgns of Respiratory DIsease Deck (32):
WHat is abnormal respiratory noise termed?
What is bronchoconstriction a component of?
cough reflex, but slower onset and longer lasting
What does coughing clear material from?
What is the neural basis of coughing?
- irritant receptors in trcheobronchial tree
- afferent input carried in vagus
- central cough centre in brain stem
- efferent motor: vagus, phrenic, intercostal, lumbar, trigem, facial hyoglossal and acessory nerves
Stimuli for ocughing?
- inhaled particles
- cold or hot air
- intramural/extramural pressure
- epithelial sloughing
- ^ epithelial permeability
How can character of cough indicate type of problem?
> upper airway: IgA mediated response: harsh, loud, non-productive
> lower airway: IgG: soft, muted, productive (swallow after coughing)
- painful conditions more muted as they dont want to cough
Where does the sneezing reflex originate?
URT - mucous membranes of nasal cavity
- easily induced by chemical or mechanical stimuli
- can be 2* to more distal sources
What reflex is most common in respiratory disease?
Where are drug targets for cough reflex?
- adrenaline agonists
> no drugs act on NANC system
which species are opioid drugs used more commonly in for coughing?
Smallies, not so much horses
What is hyperpnoea?
- ^ rate and depth of breathing
Normal respiratory rate of horse, cow, sheep, pigs, goats, foals, calves, puppies, kittens, rabbit kittens?
> horse: 8-15
> cow,sheep, pigs:10-30
> goats: 25-35
> foals and calves: 20-40
> puppies: 10-30
> kittens: 24-42
> rabbit kits: 30-60
What are the physiological and pathological cuases of tachy and hyperpnoea?
- pain, exertion, heat, anxiety (anything that stimulated SNS)
- ^ CO2
- low pH
- low O2
- compoensating metabolic acidoisis
- excessive environmental heat
- damaged or diseased CNS (resp centres)
- pain or resitrcition of breathing structures
Signs of dyspnoea?
- laboured b reathing
- abnormala rate/rhythm/character
- nostril flaring
- exaggerated intercoastal/abdominal effort
- abducted elbows
- anxious expression
-extended head and neck
- mouth breathing (except horses obligate nasal breathers)
2 causes of inspiratory distress?
> extrathoracic non-fixed airway obstruction eg. URT obstruction: laryngeal hemiplegia, soft palate disorders
> restrictive diseases (limit lung expansion) eg. pleural effusion, chest wall wont expand despite ^ effort
causes of expiratory distress
intrathoracic airway obstruction eg. bronchoconstriction associated with RAO in horses, Farmer's disease in cattle, tracheal collapse in dogs and horses
clinical sign of chronic expiratory distress?
heave line (hypertrophy of abdo muscles)
What is inspiraotry and expiratory distress combined due to?
Extra-thoracic fixed obstruction eg. intraluminal mass, foreign body
How can nasal discharge be characterised?
- Serous, mucoid, sanginous (haemmorhagic), purulent
- disa hrging ingested food/milk ? GI disease
Where does unilateral discharge tend to originate?
- structures rostral to caudal end of nasal septum
- low volume discharges from lower in resp tract can be unilateral
Where does bilateral disacharge oriniginate?
caudal structures or bilaterally affected rostral structures
What may foul smelling discharge indicate?
- anaerobic infections, necrotising conditions, pathology connected to oral cavity eg. tooth root infection in horses
What may presence of food/water indicate? ?
Communication between oral and nasal cavities eg. oronasal fistule, cleft palate
Presence of frank blood at external nares
presence of blood in sputum (coughed up)
What can epistaxis or haemoptysis be caused by?
- erosive or invasive conditions (fungal or neoplasm)
excercise associaed (EIPH)
Causes of cyanosis? Which systems do these reflect problems in?
- pulmonary: hypoxaemia eg. V/Q mismatch, alveolar hypoventilation, shunting, diffusion important
- cardiac: R_L shunting
- acquired: usually reducing agent eg. acetaminophen (paracetamol), nitrates, red maple leaf -> methaemoglobin
Where does stridor usually orginiate?
How is repiration linked to stride in horses?
- expire when leading forelimb contacts ground at GALLOP only
Potential causes of stridor?
- fixed or dynamic obstruction eg. laryngeal paralysis, brachycephalic breeds, stenotic/paralysed nares, nasal masses, soft palate elongation
What level of oxygenation is cyanosis seen at? hat is a normal level of oxygenation?
<50mmHg (normal 100mmHg)