Respiratory Pathophysiology Flashcards
What are the signs & symptoms of respiratory acidosis?
Diaphoresis, headache, tachycardia, confusion, restlessness, apprehension.
What can cause respiratory acidosis?
Gram-negative bacteremia leading to hyperventilation.
What are the signs & symptoms of respiratory alkalosis?
Rapid, deep breathing, paresthesia, light-headedness, twitching, anxiety, fear.
What can cause metabolic alkalosis?
Loss of hydrochloric acid from prolonged vomiting or gastric suctioning, or decreased plasma potassium levels.
What are the signs & symptoms of metabolic alkalosis?
Slow & shallow breathing, confusion, hypertonic muscles, twitching, restlessness, irritability, apathy, tetany, coma, seizure.
What can cause metabolic acidosis?
Diarrhea, small bowel fistulas, chronic kidney disease, hepatic disease, endocrine disease.
What are the signs & symptoms of metabolic acidosis?
Rapid & deep breathing (Kussmaul’s), fatigue, fruity breath, headache, drowsiness, lethargy, nausea, vomiting, coma.
What characterizes obstructive disorders?
Airway obstruction & reduced airway flow rates, especially with forced exhalation.
What percentage of FEV1/FVC indicates an obstructive disorder?
Less than 70%.
Which lung volumes are decreased in obstructive disorders?
Vital capacity (VC), inspiratory reserve volume (IRV), expiratory reserve volume (ERV).
Which COPD is characterized by excess mucus production?
Chronic bronchitis.
Which COPD involves destruction of terminal bronchioles & alveolar walls?
Emphysema.
What are the GOLD grades for COPD patients?
GOLD 1: mild, FEV1 >= 80; GOLD 2: between 50-80; GOLD 3: between 30-50; GOLD 4: lower than 30.
What are two types of COPD assessment tests?
CAT (over 10 symptoms) and mMRC (2 or more symptoms).
What happens to oxygen saturation during exercise for emphysema patients?
Desaturation.
What happens to oxygen saturation during exercise for chronic bronchitis patients?
May decrease, but exercise may help in earlier stages by clearing mucus.
What is panacinar emphysema?
Alveoli affected, distributed throughout lungs, loss of surface for air exchange, predominantly lower lobes, genetic.
What is centrilobular emphysema?
Most common due to smoking, affects respiratory bronchioles, primarily upper lobes, progression of chronic bronchitis.
What does an emphysema x-ray show?
Hyperlucency & formation of bullae, which are balloon-like due to hyperinflation.
What deformity results from hyperinflation in emphysema?
Barrel chest, leading to a flattened diaphragm.
How are levels of PaCO2 & PaO2 initially in emphysema patients?
Normal due to increased hyperventilation.
True or False: Cardiac output is not affected in emphysema patients.
False (slight decrease due to muscle wasting & fatigue).
What are the initial stages of emphysema characterized by?
Decreased breath sounds, increased FRC & RV, decreased FEV1, FEV1/FVC, VC, equal deficit of V & Q, increased compliance.
What gas level increases in emphysema intermediate stages?
CO2 while O2 diffusion decreases.
What happens to ventilation during forced exhalation in emphysema intermediate stages?
Decreased ventilation.
What are the end stages of emphysema characterized by?
Hypoxemia leading to pulmonary artery hypertension, edema & fluid overload from Na+ retention, right-sided heart failure, increased risk of nocturnal death, and multi-organ ischemia.
How many ribs should normally show in an x-ray?
5-7.
What can cause cyanosis in chronic bronchitis patients?
Hypoxemia.
Which COPD disease has polycythemia?
Chronic bronchitis.
What are two signs associated with cor pulmonale?
Jugular venous distension (JVD) and fluid retention/edema.
True or False: CO2 diffusion is increased with chronic bronchitis.
False.
How are PaCO2 & PaO2 affected in chronic bronchitis?
CO2 increased, O2 lowered.
What is cor pulmonale?
Right ventricular failure due to pulmonary hypertension from chronic bronchitis.
What is status asthmaticus?
Acute exacerbation of asthma leading to respiratory failure and death.
What type of asthma is allergenic with periodic exacerbations?
Juvenile asthma.
What type of asthma is intrinsic with chronic low-level bronchospasm?
Adult asthma.
What does bronchospasm in asthma lead to?
Wheezing during expiration, especially in early to mid-severe exacerbations.
What can cause inflammation of the bronchial wall in asthma?
Eosinophilic reaction.
What do asthma patients experience due to hyperinflated lungs?
Air trapping, difficulty exhaling, and reduced FEV1.
What is exercise-induced asthma often caused by?
Water or heat loss in airways leading to bronchoconstriction within minutes of completion.
What is bronchiectasis?
Dilation of bronchial walls with retained secretions, usually resulting from recurrent infections.
What is the primary treatment of bronchiectasis?
Bronchial hygiene.
What are the three types of bronchiectasis?
Cylindrical, varicose, saccular (cystic).
What characterizes restrictive disorders?
Reduction in vital capacity, which can be pulmonary (e.g., pulmonary fibrosis) or extrapulmonary (e.g., neuro-musculo-skeletal).
What else besides VC is decreased in restrictive disorders?
RV, FRC, VT, TLC, compliance.
What pressure is required in restrictive lung disease to give the same increase in volume?
Greater pressure.
What characterizes obstructive lung disease pressure/volume relationship?
Normal with normal breathing, but greater pressure needed to overcome resistance when breathing rapidly, leading to smaller volume of each breath.
What are some acute pulmonary restrictive disorders?
Atelectasis, pneumothorax, pneumonias (lobar, bronchial), acute respiratory distress syndrome (ARDS).
What are some chronic pulmonary restrictive disorders?
Bronchopulmonary dysplasia, pulmonary fibrosis, SLE, scleroderma, occupational lung diseases (silicosis, asbestosis, pneumoconiosis), lung carcinomas (bronchogenic).
What are some skeletal extrapulmonary restrictive disorders?
Fractures, kyphosis, scoliosis, rheumatoid arthritis, ankylosing spondylitis.
What are some neuromuscular extrapulmonary restrictive disorders?
Stroke, spinal cord injury, amyotrophic lateral sclerosis, multiple sclerosis, muscular dystrophy, myasthenia gravis.
What are some other extrapulmonary restrictive disorders?
Pleural effusion (empyema), abdominal ascites (pushes diaphragm up), intrathoracic surgical implants (LVAD).
What is atelectasis?
Partial collapse of lung parenchyma (alveoli).
What is microatelectasis?
Alveolar collapse perhaps related to surface tension changes.
What is obstructive/regional atelectasis?
When bronchus becomes occluded, air distal to obstructed is absorbed, leading to lung region collapse.
Which type of atelectasis is most common and occurs quickly?
Microatelectasis, most often due to bed rest & immobility.
What causes microatelectasis?
Hypoventilation and low mechanical pressure in the lung.
What disorders are associated with microatelectasis?
Respiratory distress syndrome and left ventricular failure.
What are some signs of microatelectasis?
Reduced chest wall expansion, crackles, bronchial sounds (consolidation), tracheal & mediastinal shift on x-ray.
What direction does the trachea shift in obstructive atelectasis?
Towards the collapse.
What type of pneumonia is characterized by little consolidation and inflammation of airways?
Bronchial pneumonia.
What type of pneumonia is caused by pneumococcus and involves consolidation of parenchyma?
Lobar pneumonia.
What is the exudative phase of ARDS?
Leakage of water, protein, inflammatory cells, and RBCs into interstitium & alveolar lumen, damaging alveolar epithelium & vascular endothelium.
Which alveolar cell, when damaged, is irreversible and associated with deposition of proteins?
Type I alveolar cells.
What occurs in the proliferative phase of ARDS?
Type II cells proliferate, epithelial cells regenerate, and there is a fibroblastic reaction & remodeling.
What characterizes the fibrotic phase of ARDS?
Irreversible fibrosis, development of microcysts, and collagen deposition in alveolar, vascular, & interstitial beds.
How does a patient with ARDS present?
Dyspnea, tachypnea, decreased lung compliance, pulmonary interstitial edema, x-ray shows fluffy infiltrates, hypoxemia leading to confusion, SOB, cyanosis, labored breathing.
