Week 9: Respiratory Disorders Flashcards
If someone has a low plasma PaO2, what condition are they suffering from?
Hypoxemia
State the different types of hypoxia
Hypoxic hypoxia: when PaO2 decreases even though there are normal HgB and hCt (high altitue, hypoventilation, airway obstruction)
Anemic hypoxia: Low O2 in the blood, anything that causes low Hgb
Circulatory hypoxia: Low cardiac output
Histotoxic hypoxia: Toxic substance prevents tissue from using available O2 (cyanide poisoning)
Describe Arterial Blood values
ph: 7.34-7.45
PaO2: 80-100 mmHg
PaCo2: 35-45 mmHg
HCO3: 22-26 mmol/L
SaO2: 90-100%
Epiglottitis
Common in kids 2-4 y/o
Odynophagia (painful swallowing, drooling)
Etiology: H. Influenzae
Inflammation of airway resulting in obstruction
CM: Respiratory difficulty, dysphagia, fever, inspiratory stridor, edema
Croup
Laryngotracheobronchitis (larynx, trachea, bronchi)
Fall and early winter
Kids 6mo-3 y/o
Inflammation of ENTIRE resp tract
CM:
Barking cough and inspiratory stridor
Low grade fever
worse symptoms at night
Treatment: Nebulized epinephrine
What is a Pneumothorax?
Etiology: Accumulation of air in the pleural space
Tension pneumothorax: results from penetrating or non penetrating injury
- results from buildup of air under pressure in pleural space
- air enters pleural space but cannot escape during expiration
- lung on ipsilateral (same) side collapses and forces mediastinum towards contralateral side
decreases venous return and cardiac output
Clinical manifestations of pneumothorax (without tension)
Small pneumothoraces are usually not detectable on physical exam
- Tachycardia
- Decreased or absent breath sounds on AFFECTED side
- Hyperresonance
- Chest pain on affected side
- Dyspnea
What is pleural effusion? It is reabsorbed into where?
Pathologic collection of fluid or pus in pleural cavity as result of another disease process
- Normally 5-15 mL of serous fluid in contained pleural space
- Constant movement of pleural fluid from parietal pleural capillaires to pleural space
- Reabsorbed into parietal lymphatics
Major types of pleural effusions
Transudates
Low in protein & lactate dehydrogenase (LDH)
Exudates
High in protein & LDH
Hemothorax or Hemorrhagic
Presence of blood in pleural space
Empyema
Collection of pus in pleural space (likely due to infection in pleural space)
What are the causes of pleural effusions?
Transudates: conditions leading to edema such as (i) severe heart failure; (ii) cirrhosis with ascites; (iii) nephrotic syndrome; (iv) myxedema (hypothyroidism)
Exudates: malignancies; infections like pneumonia; pulmonary embolism; post-myocardial infarction; & pancreatic disease.
Empyema: infection in pleural space
Hemothorax: chest trauma
Clinical manifestations of Pleural Effusions
Dyspnea
Decreased chest wall movement
Pleuritic pain (sharp, worsens with inspiration)
Dry cough
Absence of breath sounds
Dullness to percussion
Decreased pleural fremitus over affected area
Contralateral tracheal shift (massive effusion)
Describe pulmonary circulation
Pulmonary circulation is high flow and low pressure normally
Primary vs. Secondary Pulmonary HTN
Primary (idiopathic) pulmonary HTN is rapidly progressive and occurs more often in women; long-term prognosis is poor and medical treatment usually ineffective
Secondary HTN: from increased pulmonary blood flow, increased resistance to blood flow and increased left atrial pressures
This is caused from known risk factors such as HF, Smoking, bad habits etc
Pathogenesis of Pulmonary HTN
Vasconstriction, obstruction, loss of capillary bed, mitral stenosis, left ventricular heart failure, artial or ventricular septal defects, polycythemia, congenintal heart disease
What are the three contributing factors to thromboemoli formation? What is this called?
Virchow’s triad:
- Venous stasis/sluggish blood flow
- Hypercoagulability
- Damage to venous wall
