Manifestations of respiratory system dysfunctions

1. Manifestations of respiratory system dysfunctions M. Tatár

2. Cardinal respiratory symptoms and signs cough sputum dyspnoea wheezing cyanosis chest pain

3. Disorders of lung mechanics

4. Disorders of the lung mechanics • Airway obstruction • nasal cavity: nasal congestion • pharynx: collapse during sleep • larynx: suffocation • central aw: • trachea: stridor • main bronchi: dyspnoea, wheezing • lobar bronchi: asymptomatic or minor dyspnoea • peripheral aw: dyspnoea • Lung parenchyma ( compliance): dyspnoea • Chest wall (abnormalities): dyspnoea • Respiratory muscles (fatigue): dyspnoea

5. Disorders of airway defence mechanisms

6. Disorders of airways defence mechanisms • Nasal cavity • sneezing • nasal discharge • Airways • Cough: acute respiratory infections, foreign body aspiration, chronic bronchitis, chronic cough • Haemoptysis • Expectoration - Sputum • mucoid (mainly macrophages) • purulent (neutrophils) • Pneumococcus - bloody or rust-colored • Pseudomonas, Haemophilus - green sputum

7. Hyperplasia and hypertrophy of submucosal glands

8. Cough • Physiologic reflex • Pathologic reflex • Acute cough • Chronic cough • Rhinitis/sinusitis • Asthma • Gastroesophageal reflux disease

9. Disorders of gas exchange

10.  ventilatory drive 100 40 50 50 PaO2 PaCO2 120 30 70% chemoreceptors SaO2 100% hypoxemia normocapnia hypoxemia hypercapnia

11. Disorders of gas exchange Respiratory insufficiency (failure) • Hypoxemic • Decreased ventilation/perfusion ratio • Venous admixture (right-to-left intrapulmonary shunt) • Diffusion impairment • Hypercapnic • Overall alveolar hypoventilation • Critical amount of the compartments with low V´/Q´ ratio + limits for hyperventilatory compensation

12. Hypoxemia Tachycardia, tachypnea, dyspnoea, mental confusion and irritability Secondary polycythemia ( hematocrit) Cyanosis threshold for central cyanosis is a capillary reduced haemoglobin content of 50 g/L !!! ancillary non-specific signs

13. Relation between SaO2 and arterial Hb

14. Cyanosis • Central • haemiglobin – methemoglobin, sulphhemoglobin •  content of reduced haemoglobin • Heart disorders – lung congestion • Lung disorders • acute: pneumonia, lung oedema • chronic: COPD, severe lung fibrosis • Peripheral • local perfusion disorders • False • pigmentation (silver)

15. Central cyanosis

16. Hypercapnia Morning headaches Papilloedema, dilated conjunctival and superficial facial blood vessels CO2 narcosis (rapid accumulation): anxiety may progress to delirium and somnolence

17. Disturbed regulation of breathing Cheyne-Stokes breathing Sleep apnoea Hyperventilation (tetany) Gasping Hypopnoea

18. Cheyne-Stokes breathing

19. Dyspnoea - breathlessness • Air hunger, awareness of the act of breathing, chest tightness • Sensations: shortness of breath, feeling puffed, inability to get enough air, suffocation • Subject´s feelings – needs for increased ventilatory activity; mechanical rather than chemical disturbances • Tachypnoea with either shallow or deep breathing • Increased workload of respiratory muscles – normal gas exchange cannot be achieved without increased ventilatory effort

20. Pathophysiology of dyspnoea • Hyperventilation – acute hypoxemia • Relative hyperventilation - decreased ventilatory surface (atelectasis, pleural effusion, lung congestion, pneumothorax) • Disordered lung mechanics (most frequent cause) - Upper airways stenosis - Increased airways resistance = obstruction of peripheral airways (asthma, COPD, heart failure) - Decreased muscle force (polyomyelitis, diaphragm paralysis, myasthenia gravis) - Limited chest movements (kyphoscoliosis) !!! acute or chronic state; rest or physical activity

21. Causes of dyspnoea Oxygen content in atmosphere Oxygen consumption during physical activity Lung function disorders Heart function disorders Decreased haemoglobin content (during exercise) Respiratory centre dysfunction (Cheyne-Stokes, acidosis) Stimulation of airway and lung nerve-endings (pneumonia, lung congestion) Obesity Emotive factors (chronic hyperventilatory syndrome) Brain disorders Metabolic disorders – hyperthyroidism

22. Systemic non-respiratory responses Fever Weakness, fatigue Decreased exercise tolerance Immunity: eosinophilia Weight loss: advanced disease Distant effects: finger clubbing and osteoarthropathy (periosteal overgrowth)

23. Primary respiratory disorders can significantly affect the function of other systems Most frequently CVS (the lung is the recipient of the entire cardiac output through the lesser circulation) • Cor pulmonale: elevated jugular venous pulse, peripheral oedema • Massive pulmonary embolism and tension pneumothorax  circulatory shock: hypotension, weakness, pallor, cold sweat, oliguria, and develops impaired mentation • Obstructive sleep apnoea syndrome: daytime sleepiness, right heart failure, systemic arterial hypertension