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What is the normal resting respiratory rate? 14-16/min What is the primary stimulus of the central regulation of breathing, under normal conditions? Partial pressure of CO2 in the arterial blood What are the characteristics of Kussmaul breathing? The depth and the rate of breathing increase What are the characteristics of Cheyne-Stokes respiration? Periodic breathing with apnea, followed by a gradual increase, then decrease of the depth of breathing, ending in apnea again List two important pathological factors which influence the sensitivity of the respiratory center in the medulla oblongata. narcotic analgesic drugs (e.g. morphine), sleeping pills, sedatives severe chronic hypercapnia Please, list the forms of the sleep apnea syndrome! central and (peripheral) obstructive Please, define the characteristics of apnea! Respiratory arrest during expiration Please, define apneusis! Respiratory arrest during inspiration Please, define dyspnea! Shortness of breath, a subjective sensation of abnormal or uncomfortable breathing. Please, define the typical breathing pattern of obstructive lung diseases! Slow and deep breathing Please, define the typical breathing pattern of restrictive lung diseases! Frequent (rapid), superficial breathing Please, define total ventilation (per minute) at rest! About 8 liters per minute (16x500ml) What is the anatomical dead space? From 500 ml tidal volume (VT) the anatomical dead space is about 150 ml. Definition and normal value of alveolar ventilation: Alveolar ventilation is the gas exchange within the alveoli within a certain time period (1 min). From an 8000-ml (16 x 500 ml) total ventilation (at rest) 350 ml x 16 = 5600 ml reaches the alveoli. What kind of breathing pattern increases the dead space ventilation? Frequent, superficial breathing Please, list the two most important factors that determine the work of respiration! Elastic resistance of the ventilatory pump (lungs and chest) and nonelastic resistance of the airways. Please, define airway resistance! It shows the change in the alveolar pressure that is needed to create a 1-l/s airflow (a unit of airflow). The normal value of the airway resistance (Raw, measured by wholebody plethysmography) is under 0.3 kPa/l/s.

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Please, define compliance in the respiratory system? What is the normal value? The change in lung volume caused by one unit of change (1 kPa) in transpulmonary pressure. 2 l/kPa. How does the compliance change in emphysema? It increases How does the compliance change in lung fibrosis? It decreases Please, list the forms of respiratory failure! Partial or Type I Global or Type II Please, define the characteristics of partial respiratory failure! Hypoxemia - paO2 < 60 mmHg Please, define the characteristics of global respiratory failure (3)! Hypoxemia - paO2 < 60 mmHg Hypercapnia- paCO2 > 50 mmHg Respiratory acidosis What does latent respiratory insufficiency mean? Pathological blood gas values can be observed only during exercise, at rest the blood gas values are normal. Please, define ventilation/perfusion ratio (V/Q) and its optimal value! V/Q~1 (V=~8 l/min, Q=~5l/min) Please, list five major etiological factors of respiratory failure! Alveolar hypoventilation Ventilation/perfusion mismatch Disorders of the alveolo-capillary diffusion Right-left shunt A decrease in PiO2 (oxygen partial pressure of the inspired air decreases, high altitude) Please, define alveolar hypoventilation! Alveolar ventilation is insufficient compared to the metabolic requirements of the body. An increase in the arterial paCO2 (> 44 mmHg) indicates alveolar hypoventilation. In addition to that, arterial paO2 is always under 100 mmHg. Please, list the long-term consequences of alveolar pAO2↓ (min.3)! pulmonary vasoconstriction → pulmonary hypertension → chronic cor pulmonale → right ventricular failure Please, list the long-term consequences of arterial pO2↓! erythropoietin ↑ → polyglobulia → high blood viscosity → blood pressure (RR) increases Please, define alveolar hyperventilation! Alveolar ventilation exceeds the needs of the body, arterial paCO2 decreases (< 36 mmHg). What type of pH abnormality develops during alveolar hyperventilation? Respiratory alkalosis What are the consequences of hypocapnia (pCO2↓) in the cerebral circulation? cerebral vasoconstriction→dizziness, loss of consciousness What shift of the Hb-oxygen-saturation curve will occur in respiratory alkalosis?

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A left shift will develop →Hb binds oxygen too strongly→tissue oxygenation is decreased Please, list the types of tissue hypoxia (4)! Hypoxemic Stagnation (Ischemic) Anemic Histotoxic Please, list the main etiological factors of hypoxemic hypoxia (4)! High altitude Alveolar hypoventilation V/Q mismatch Diffusion disorders Right-to-left shunt Please, list the main etiological factors of anemic hypoxia (4)! Anemias (iron-deficiency, folate- or B12-deficiency, aplastic anemia, hemolytic anemias) Methemoglobinemia Abnormal hemoglobins CO poisoning Please, name at least two causes of generalized ischemic (stagnation) hypoxia! circulatory shock, severe heart failure, congenital heart malformation („blue baby”) Please, name at least two causes of regional ischemic (stagnation) hypoxia! Cold environment, venous thrombosis, peripheral artery disease (obstruction of peripheral arteries). Please, list the main etiological factors of histotoxic hipoxia? Cyanide poisoning Uremia Intracellular osmotic or pH abnormalities What is the normal partial oxygen pressure in the arterial blood? paO2~100 mmHg What is the normal partial carbon-dioxide pressure in the arterial blood? paCO2 ~40 mmHg What is the normal partial oxygen pressure in the mixed venous blood? pvO2~40 mmHg What is the normal partial carbon-dioxide pressure in the mixed venous blood? pvCO2 ~46 mmHg What is the hemoglobin-oxygen saturation like in the arterial blood? ~100% What is the hemoglobin-oxygen saturation like in the mixed venous blood? ~75% In general, how many mls of oxygen may be released from each 100 ml unit of arterial blood in healthy adults? ~20 ml What are the typical alterations of lung function tests in restrictive lung disorders (2)? Decreased static lung volumes Tiffeneau index is normal What is the Tiffeneau index?

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FEV1/FVC (Forced expiratory volume in one second /forced expiratory vital capacity) What are the typical alterations of lung function tests in obstructive lung diseases? Tiffeneau index < 70% Please, define the major feature of dyspnea! An unpleasant conscious effort in breathing Is dyspnea always associated with respiratory failure? No, it isn’t. Is respiratory failure always associated with dyspnea? No, it isn’t. What is the most frequent/important detectable cause of dyspnea? The increase in the work of breathing Please, define the forms of anatomical shunt in the lung (2)! Bronchial circulation Real arterio-venous shunts What does it mean, when the V/Q ratio is infinitely high? (Division by zero) Normal (maintained) ventilation and zero (blocked) perfusion What does it mean, when the V/Q ratio is 1? The ventilation/perfusion ratio is optimal What does it mean, when the V/Q ratio is zero? Zero ventilation with normal (maintained) perfusion How thick is the alveolo-capillary membrane? A few μm-s Please, characterize the alveolo-capillary oxygen pressure gradient! 100 mmHg (alveoli) - 40 mmHg (capillary blood) = 60 mmHg (pressure difference) What is the size of the diffusion surface in the lungs? 70-90 m2 Please, define the contact time in the lungs! It is 0.75 sec at rest, and decreases to 0.30 sec during exercise. Please, define cyanosis! Cyanosis is the blue/livid discoloration of the skin and the mucosa. What is the cause of cyanosis? Reduced Hb-content in the capillary blood reaches 40-50g/l. What types of hypoxia lead to cyanosis? Hypoxemic hypoxia Stagnation (ischemic) hypoxia What is the tidal volume? Tidal volume in the lungs is the amount (volume) of air inhaled and exhaled with each normal breath (about 500 ml). What type of obstructive disorder may cause inspiratory difficulty? Extrathoracic airway obstruction What type of obstructive disorder may cause expiratory difficulty? Intrathoracic airway obstruction What is the circulatory consequence of hypoxia in the pulmonary circulation? It triggers vasoconstriction What is the circulatory consequence of hypoxia in the systemic circulation? It triggers vasodilation What is the surfactant and what is its function in the lungs?

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Surfactant is a phospholipid that decreases surface tension, so it keeps the alveoli open Which hormons can stimulate or inhibit the production of surfactant (3)? Inhibit: insulin Stimulate: corticosteroids, thyroxin What is the most important feature of bronchial asthma? Transient, reversible airway obstruction What type of leukocyte is the most important in the pathogenesis of bronchial asthma? Eosinophil granulocyte What type leukocyte is the most important in the pathogenesis of chronic bronchitis? Neutrophil granulocyte Which are the most important allergens in bronchial asthma (min. 2)? Pollens (ragweed), house dust mite, fur or/and urine of animals Which are the most important scientifically proven etiological factors of chronic bronchitis? Smoking, air-pollution, alpha1-antitrypsin deficiency. Which respiratory disorder is characteristic and frequent in neonates? Infant respiratory distress syndrome (IRDS) What is the most important pathogenetic factor in the development of the infant respiratory distress syndrome? Surfactant deficiency What are the major characteristics of lung edema in adult/acute respiratory distress syndrome /ARDS/ (2)? It is of non-cardiac origin, rich in proteins The progression of which disorders are worsened by smoking (min. 4)? Chronic bronchitis, emphysema, atherosclerosis, osteoporosis, peptic ulcer What percentage of patient suffering from chronic bronchitis are smokers? About 90% Which respiratory disorders occur most frequently in the elderly (4)? Kyphoscoliosis, emphysema, pneumothorax, chronic bronchitis, lung cancer, pneumonia

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