N502 Pathophysiology Exam 2
Discuss the role of inflammation in asthma - ANS-Early asthmatic response: bronchospasm
(immediate peaks 30-60 min, lasts 1-2 hours)
Exposure to antigen, triggers IgE -> inflammatory response
Compare and contrast the clinical symptoms and underlying mechanisms of bacterial
pneumonia, viral pneumonia. - ANS-- Inflammatory reaction in the alveoli and interstitium
caused by an infectious agent
- Causative microorganism influences symptoms and signs, treatment and prognosis
Causes
- Aspiration of oropharyngeal secretions composed of normal bacterial flora or gastric contents
(25%-35%)
- Inhalation of contaminants
- Virus
- Mycoplasma
- Contamination from the systemic circulation
- Bacteremia from infections in the body or IV drug abuse
Patho
- Acquired when normal pulmonary defense mechanisms are compromised
- Aspiration of oropharyngeal secretion is the most common route of lower respiratory tract
infection.
- Inhalation of microorganisms.
- Bacteria from bacteremia.
Organism enters lung, multiply, and trigger pulmonary inflammation
- Inflammatory response to organism
- Alveolar spaces fill with fluid and inflammatory cells invade the site
- Acute bacterial pneumonia can be associated with significant V/Q mismatch and hypoxia d/t
fluid
- Viral pneumonia does not produce exudative fluids
S/S
Presentation varies due to pathogen, age of pt, and severity of disease
- Some just have fever, others have rales (crackles) and bronchial breath sounds over affected
lung.
- Pleuritic chest pain, myalgia, headache, chills, fever, productive cough, chest splinting,
tachycardia, dyspnea, tachypnea
- Viral pneumonia can present with fever, cough, hoarseness with wheezing and/or rales
,- Mycoplasma pneumonia is common in older children and adults. Fever cough, headache and
malaise
On auscultation: crackles, wheezing, bronchial breath sounds, breath sounds may be
decreased or absent, tactile fremitus, dullness on percussion
Differentiate between hypoxia and hypoxemia. - ANS-
Hypoxia - ANS-Reduced oxygenation of cells in tissues
- Difficult to measure (assume when blood flow or PaO2 is low)
- Can be hypoxemia
- Low cardiac output
- Shock
Hypoxemia - ANS-Reduced oxygenation of arterial blood
- Measured by ABG or pulse oximetry (O2 saturation)
Caused by
- Decreased available O2 at alveoli
- Altered diffusion of O2 into the blood (V/Q mismatch)
- Altered perfusion of pulmonary capillaries
Define acute respiratory failure and identify risk factors. - ANS-Impaired Gas Exchange
resulting in abnormal ABGs
- PaO2 ≤ 60 mmHg; PaCO2 ≥ 50mmHg; pH ≤ 7.3 on room air
Caused by direct or indirect injury to lungs, airways, or chest wall (physical injury, or disease
processes)
- A potential complication of any major surgical procedure
- Common complications include atelectasis, pneumonia, pulmonary edema, pulmonary emboli
Symptoms vary with the cause (hypoxemia or hypercapnia)
- Headache, dyspnea, confusion, restlessness, hypertension followed by hypotension and
tachycardia...
Treatment depends on primary cause - often both
- hypercapnia (↑CO2)-inadequate arteriolar ventilation
-Requires ventilatory support
- hypoxemic - inadequate O2 exchange between alveoli and capillaries
- Requires supplemental O2
Describe the pathophysiology associated with pulmonary edema and acute respiratory distress
syndrome. - ANS-Pathophysiology
- Acute injury and inflammation to the alveolocapillary membrane
, Pulmonary inflammation
Increased capillary permeability
Severe pulmonary edema*
Shunting
V/Q mismatch
Hpoxemia
Discuss the risk factors and pathologic changes associated with pulmonary hypertension. -
ANS-Risk Factors:
Classified into several groups based on cause
- No known cause
- Heart disease
- Chronic lung disease or hypoxia (COPD common)
- Multifactorial mechanisms (blood, metabolic and systemic diseases)
Hypoxemia causes vasoconstriction of pulmonary arteries
Pathologic changes:
- Endothelial dysfunction - ↑ vasoconstrictors, ↓ vasodilators
- Hypertrophy of smooth muscles in the pulmonary artery wall, narrowing the small pulmonary
artery (arterioles)
- Remodeling: Fibrosis and thickening of vessel walls increasing vascular resistance
- ↑ pressures in the lung, ↑pressures in right ventricle
Describe similarities, clinical manifestations, underlying mechanisms, and consequences of
obstructive pulmonary diseases. - ANS-Emphysema
- Progressive loss of lung tissue
- "Pink puffer"
- Weight loss
- Mild hypoxemia, no hypercapnia initially
- Hypoventilation and hypercapnia noted in later stages
- Few secretions
Chronic Bronchitis
- Chronic airway inflammation
- "Blue bloater"
- Obese
- Hypoxemia and hypercapnia
- Increased hematocrit
- Cor pulmonale
- Lots of secretions
Chronic Bronchitis - ANS-- Hyper secretion of mucus and chronic productive cough for at least
3 months of the year for at least 2 consecutive years.
Discuss the role of inflammation in asthma - ANS-Early asthmatic response: bronchospasm
(immediate peaks 30-60 min, lasts 1-2 hours)
Exposure to antigen, triggers IgE -> inflammatory response
Compare and contrast the clinical symptoms and underlying mechanisms of bacterial
pneumonia, viral pneumonia. - ANS-- Inflammatory reaction in the alveoli and interstitium
caused by an infectious agent
- Causative microorganism influences symptoms and signs, treatment and prognosis
Causes
- Aspiration of oropharyngeal secretions composed of normal bacterial flora or gastric contents
(25%-35%)
- Inhalation of contaminants
- Virus
- Mycoplasma
- Contamination from the systemic circulation
- Bacteremia from infections in the body or IV drug abuse
Patho
- Acquired when normal pulmonary defense mechanisms are compromised
- Aspiration of oropharyngeal secretion is the most common route of lower respiratory tract
infection.
- Inhalation of microorganisms.
- Bacteria from bacteremia.
Organism enters lung, multiply, and trigger pulmonary inflammation
- Inflammatory response to organism
- Alveolar spaces fill with fluid and inflammatory cells invade the site
- Acute bacterial pneumonia can be associated with significant V/Q mismatch and hypoxia d/t
fluid
- Viral pneumonia does not produce exudative fluids
S/S
Presentation varies due to pathogen, age of pt, and severity of disease
- Some just have fever, others have rales (crackles) and bronchial breath sounds over affected
lung.
- Pleuritic chest pain, myalgia, headache, chills, fever, productive cough, chest splinting,
tachycardia, dyspnea, tachypnea
- Viral pneumonia can present with fever, cough, hoarseness with wheezing and/or rales
,- Mycoplasma pneumonia is common in older children and adults. Fever cough, headache and
malaise
On auscultation: crackles, wheezing, bronchial breath sounds, breath sounds may be
decreased or absent, tactile fremitus, dullness on percussion
Differentiate between hypoxia and hypoxemia. - ANS-
Hypoxia - ANS-Reduced oxygenation of cells in tissues
- Difficult to measure (assume when blood flow or PaO2 is low)
- Can be hypoxemia
- Low cardiac output
- Shock
Hypoxemia - ANS-Reduced oxygenation of arterial blood
- Measured by ABG or pulse oximetry (O2 saturation)
Caused by
- Decreased available O2 at alveoli
- Altered diffusion of O2 into the blood (V/Q mismatch)
- Altered perfusion of pulmonary capillaries
Define acute respiratory failure and identify risk factors. - ANS-Impaired Gas Exchange
resulting in abnormal ABGs
- PaO2 ≤ 60 mmHg; PaCO2 ≥ 50mmHg; pH ≤ 7.3 on room air
Caused by direct or indirect injury to lungs, airways, or chest wall (physical injury, or disease
processes)
- A potential complication of any major surgical procedure
- Common complications include atelectasis, pneumonia, pulmonary edema, pulmonary emboli
Symptoms vary with the cause (hypoxemia or hypercapnia)
- Headache, dyspnea, confusion, restlessness, hypertension followed by hypotension and
tachycardia...
Treatment depends on primary cause - often both
- hypercapnia (↑CO2)-inadequate arteriolar ventilation
-Requires ventilatory support
- hypoxemic - inadequate O2 exchange between alveoli and capillaries
- Requires supplemental O2
Describe the pathophysiology associated with pulmonary edema and acute respiratory distress
syndrome. - ANS-Pathophysiology
- Acute injury and inflammation to the alveolocapillary membrane
, Pulmonary inflammation
Increased capillary permeability
Severe pulmonary edema*
Shunting
V/Q mismatch
Hpoxemia
Discuss the risk factors and pathologic changes associated with pulmonary hypertension. -
ANS-Risk Factors:
Classified into several groups based on cause
- No known cause
- Heart disease
- Chronic lung disease or hypoxia (COPD common)
- Multifactorial mechanisms (blood, metabolic and systemic diseases)
Hypoxemia causes vasoconstriction of pulmonary arteries
Pathologic changes:
- Endothelial dysfunction - ↑ vasoconstrictors, ↓ vasodilators
- Hypertrophy of smooth muscles in the pulmonary artery wall, narrowing the small pulmonary
artery (arterioles)
- Remodeling: Fibrosis and thickening of vessel walls increasing vascular resistance
- ↑ pressures in the lung, ↑pressures in right ventricle
Describe similarities, clinical manifestations, underlying mechanisms, and consequences of
obstructive pulmonary diseases. - ANS-Emphysema
- Progressive loss of lung tissue
- "Pink puffer"
- Weight loss
- Mild hypoxemia, no hypercapnia initially
- Hypoventilation and hypercapnia noted in later stages
- Few secretions
Chronic Bronchitis
- Chronic airway inflammation
- "Blue bloater"
- Obese
- Hypoxemia and hypercapnia
- Increased hematocrit
- Cor pulmonale
- Lots of secretions
Chronic Bronchitis - ANS-- Hyper secretion of mucus and chronic productive cough for at least
3 months of the year for at least 2 consecutive years.
