Pathology Exam-respiratory Flashcards
What are the defence mechanisms of respiratory system?
- air purifying (physical, mucociliary clearance)
- immune (alveolar/BALT, humoral)
- cough/sneeze (removing of pathogens)
What are the natural physical barriers?
- nasal hairs
- turbinates
What is mucociliary clearance?
Self-clearing mechanism of tracheobronchial tree
- respiratory epithelium
- cilia surrounded by mucus fluid film
- second viscous film of mucus
- cilia moves fluid towards pharynx
What are the cellular mechanisms?
Alveoli: -phagocytosis of very small particles -alveolar macrophage -neutrophils BALT: -respiratory tract-dedicated lymphoid tissue - in submucosa of bronchi
What is the humoral defence?
Present in alveolar surface fluid, made by type 2 cells
- lactoferrin=interferes with microbial iron metabolism
- lysozyme= general antimicrobial activity
- interferon= can enhance non-immune resistance
- surfactant= non- immune opsonization of gram+ bacteria
What is the respiratory tract microbial defence system?
Layered defense mechanisms
- inhaled bacteria is trapped by mucus
- bacteria penetrating mucus layer are facing antimicrobial peptides and phagocytes
- adaptive immune system= BALT
What is cough?
Second most important defence
Phases:
- deep inspiration
- respiratory muscle contraction, closed glottis
- glottis opening and air expelled with high velocity
What are the mechanisms for coughing?
-Irritation of cough receptors (vagus+phrenic Nerve)
-signal to cough center in brain stem
- signal to respiratory+laryngeal muscles (vagus, phrenic, spinal nerves)
-cough
Receptors in:
-Pharynx
-larynx, tracheobronchal tree, pleura
- stomach
- ear duct
- nose
- pericardium
- diaphragm
What are the types of cough?
Dry - unproductive -should be stopped Moist - productive - should not be stopped
What is sneeze?
Semi-autonomous convulsive expulsion from lungs through nose and mouth
Cleans nasal cavities
- irritation
- stimulation of nasal cavity nerve cells
- signal by vagus N to sneeze center in brain stem
-activation of muscles in pharynx, trachea, thorax
- violent airexpulsion from lungs, nose, mouth
What is dyspnoea?
Abnormal ventilation -orthopnoeic position - respiratory alteration Aetiology: -respiratory -circulatory -blood related -neurological
What is apnoea?
Absence of ventilation
What is hyperventilation?
Abnormally fast + deep breathing
What is hypoventilation?
Respiration either too slow or superficial
What is tachypnoea?
Abnormally rapid breathing
Causes:
-respiratory center stimulation (CNS trauma/inflammation, anemia)
- thoracic pain
What is bradypnoea?
Abnormally slow breathing
Causes:
-Respiratory center depression
- airway obstruction
What are the types of breathing alterations?
Abdominal breathing - most effort made by abdominal muscles -cattle Costal breathing - respiration produced by intercostal muscles - produces movement of ribs - carnivores Horses have costo-diaphragmatic breathing
What can be reasons for pathological costal breathing?
- mechanical obstruction of airways (gastric dilation, pregnancy)
- reflex inhibition of diaphragm (peritoneal disorders)
What can be causes for pathological diaphragmatic breathing?
- pain
- intercostal paralysis
- rib fractures
What can be the reasons for increased respiratory depth?
Deep breathing
- partial obstructions
What can be the reasons for decreased respiratory depth?
Shallow breathing
- costal or pleural pain
What is normal respiratory rhythm?
Inspiration is shorter than exhalation
- time between insp and exp between 1,2-1,5s
- cow fastest, equine slowest
- alterations= arrhythmia
Describe the respiratory movement
Inspiration - short - uniform - active Exhalation - 2 phases, first is abrupt
What are types of respiration rhythm alterations?
Cheyne-Stokes - respiratory center damage - severe hypoxia -cranial hypertension - rapid breathing altered with apnoea Biot - cranial hypertension - brain damage - hyperpnoea altered with apnoea Kussmaul - laboured, quick, deep -metabolic acidosis -hyoerpnoea
What is inspiratory dyspnoea?
Aetology: -obstacle cranial to intrathoracic trachea (upper airways) Characteristics: - prolonged and deep inspiration - increased respiratory sound - nostril dilation
What is expiratory dyspnoea?
Problems in breathing out -bronchial -intrathoracic trachea Characteristics: - abdominal expiration - reinforced and prolonged expiration - heaves lines in horses
What is mixed dyspnoea?
Problems breathing both in and out
- pneumonia
- edema
- pleural disease
What is exertional vs resting dyspnoea?
Exertional= after excercise Resting= in resting state
