«Internal Medicine»
CHAPTER “PULMONOLOGY”
1. Theme of practical lesson # 19: Pulmonary insufficiency
2. Importance of the problem.
One of the most common conditions that accompany the course of a large group of
lung diseases are respiratory failure (synonym pulmonary insufficiency - PI).
Among these can be identified primarily nosology: bronchial asthma, chronic
obstructive pulmonary disease, bronchiectasis, lung cystic fibrosis, oncopathology,
interstitial lung disease, pneumonia, lung disease caused by drugs and others.
In the literature, there is no exact data on the incidence of PI. There are some data
on PI in certain diseases. For example, pneumonia accompanied by pulmonary
insufficiency in 15-65% of cases. After thoracic surgery it develops in 3,5-34% of
cases, in a case of COPD - respiratory failure develops always. Given the fact that
the frequency of COPD now occupy the third-fourth place and their number
doubles every 5 years, pulmonary insufficiency considered as prevailing syndrome.
3. Content of lesson
Definition
PI – it is a condition in which the lung cannot fulfill its primary function of maintaining adequate
gas exchange leading to PaO2 less than 60mmHg and/or PaCO2 more than 50 mmHg .
Etiology
- Airway obstruction: Airway inflammation, tumor, foreign bodies, fibrosis scar COPD and
asthma
- Alveolar or interstitial lung diseases: pneumonia, emphysema, pulmonary tuberculosis, diffuse
interstitial pulmonary fibrosis, pulmonary edema
- Pulmonary vascular diseases: Pulmonary embolism, pulmonary vasculitis
- Chest wall or pleural diseases: Flail chest caused by trauma, pneumothorax, severe spinal de-
formity, massive pleural effusion
- Neuromuscular diseases: Cerebrovascular diseases, craniocerebral trauma, cerebritis and seda-
tive-hypnotic, poliomyelitis, polyneuritis, myasthenia gravis
Pathogenesis
Hypoxemia
• Alveolar ventilation ↓
• FiO2↓
• Diffusion abnormality
• V/Q mismatch : V/Q>0.8 or V>Q - dead space effect
A-V shunt (V/Q < 0.8 or Q>V)
Hypercapnia(CO2 retention)
• CO2 production↑ (fever, infection, sepsis, epilepsy)
Alveolar ventilation ↓(neuromuscular diseases or fatigue of respiratory muscles
• obstructive ventilation disorder)
Classification
According to pathophysiology and arterial blood gas analysis:
Type I: A failure of gas exchange
Hypoxemia, PaO2 < 60 mmHg
Type II: A failure of ventilation
, 2
PaO2 < 60 mmHg, PaCO2 > 50 mmHg
PaO2 > 60 mmHg, PaCO2 >50 mmHg
Iatrogenic
According to the involved site
Central respiratory failure
• Change of respiratory rhythm and frequency
Peripheral respiratory failure
• Dyspnea
According to onset of respiratory failure
- Acute, develops in seconds or hours
- Chronic, develops in days or longer, elevated HCO3-
- Acute onset of Chronic respiratory failure
- Have no definitive borderline
According to mechanisms
Pump failure is caused by dysfunction of respiratory pump; characterized by
- Low respiratory drive due to central or peripheral nervous system diseases, neuromuscular
junction problem or fatigue of respiratory muscles→hypoventilation
- manifested as type Ⅱ respiratory failure
Lung failure is caused by disorder of lung parenchyma, pulmonary vascular or airway obstruc-
tion
-Airway obstruction → hypoventilation，manifested as type Ⅱ respiratory failure
- Disorder of lung parenchyma → dysfunction of oxygenation, manifested as hypoxemia
- Disorder of pulmonary vascular system → ventilation/perfusion mismatch, manifested as hy-
poxemia
Classification of PI (LF)according to functional parameters
Restrictive: TLC < 80%, FEV1/VC >85%
Obstructive: FEV1/VC)< 70%
Mixed
Classification of PI according to degree of severity
Degree РаО2, mmHg SaO2, %
Normal ≥80 ≥95
I 60–79 90–94
II 40–59 75–89
III <40 <75
Influence of hypoxemia
Central nervous system
Oxygen consumption of brain--3 ml/100g·min
If jugular vein PaO2 <20mmHg: unconsciousness, coma
PaO2 <20mmHg: irreversible damage to nerve cells in several minutes (4~5min)
Mild hypoxemia: impaired concentration, disorientation, hypomnesia
Severe hypoxemia: dysphoria, unconsciousness, coma
Cardiovascular system
Myocardium oxygen consumption: 10 ml/100g/min
Early stage of acute hypoxia–stimulation of sympathetic nerve→HR、BP、CO
Chronic hypoxia → small pulmonary arteries contraction → pulmonary hypertension— Cor pul-
monale
Respiratory system
CHAPTER “PULMONOLOGY”
1. Theme of practical lesson # 19: Pulmonary insufficiency
2. Importance of the problem.
One of the most common conditions that accompany the course of a large group of
lung diseases are respiratory failure (synonym pulmonary insufficiency - PI).
Among these can be identified primarily nosology: bronchial asthma, chronic
obstructive pulmonary disease, bronchiectasis, lung cystic fibrosis, oncopathology,
interstitial lung disease, pneumonia, lung disease caused by drugs and others.
In the literature, there is no exact data on the incidence of PI. There are some data
on PI in certain diseases. For example, pneumonia accompanied by pulmonary
insufficiency in 15-65% of cases. After thoracic surgery it develops in 3,5-34% of
cases, in a case of COPD - respiratory failure develops always. Given the fact that
the frequency of COPD now occupy the third-fourth place and their number
doubles every 5 years, pulmonary insufficiency considered as prevailing syndrome.
3. Content of lesson
Definition
PI – it is a condition in which the lung cannot fulfill its primary function of maintaining adequate
gas exchange leading to PaO2 less than 60mmHg and/or PaCO2 more than 50 mmHg .
Etiology
- Airway obstruction: Airway inflammation, tumor, foreign bodies, fibrosis scar COPD and
asthma
- Alveolar or interstitial lung diseases: pneumonia, emphysema, pulmonary tuberculosis, diffuse
interstitial pulmonary fibrosis, pulmonary edema
- Pulmonary vascular diseases: Pulmonary embolism, pulmonary vasculitis
- Chest wall or pleural diseases: Flail chest caused by trauma, pneumothorax, severe spinal de-
formity, massive pleural effusion
- Neuromuscular diseases: Cerebrovascular diseases, craniocerebral trauma, cerebritis and seda-
tive-hypnotic, poliomyelitis, polyneuritis, myasthenia gravis
Pathogenesis
Hypoxemia
• Alveolar ventilation ↓
• FiO2↓
• Diffusion abnormality
• V/Q mismatch : V/Q>0.8 or V>Q - dead space effect
A-V shunt (V/Q < 0.8 or Q>V)
Hypercapnia(CO2 retention)
• CO2 production↑ (fever, infection, sepsis, epilepsy)
Alveolar ventilation ↓(neuromuscular diseases or fatigue of respiratory muscles
• obstructive ventilation disorder)
Classification
According to pathophysiology and arterial blood gas analysis:
Type I: A failure of gas exchange
Hypoxemia, PaO2 < 60 mmHg
Type II: A failure of ventilation
, 2
PaO2 < 60 mmHg, PaCO2 > 50 mmHg
PaO2 > 60 mmHg, PaCO2 >50 mmHg
Iatrogenic
According to the involved site
Central respiratory failure
• Change of respiratory rhythm and frequency
Peripheral respiratory failure
• Dyspnea
According to onset of respiratory failure
- Acute, develops in seconds or hours
- Chronic, develops in days or longer, elevated HCO3-
- Acute onset of Chronic respiratory failure
- Have no definitive borderline
According to mechanisms
Pump failure is caused by dysfunction of respiratory pump; characterized by
- Low respiratory drive due to central or peripheral nervous system diseases, neuromuscular
junction problem or fatigue of respiratory muscles→hypoventilation
- manifested as type Ⅱ respiratory failure
Lung failure is caused by disorder of lung parenchyma, pulmonary vascular or airway obstruc-
tion
-Airway obstruction → hypoventilation，manifested as type Ⅱ respiratory failure
- Disorder of lung parenchyma → dysfunction of oxygenation, manifested as hypoxemia
- Disorder of pulmonary vascular system → ventilation/perfusion mismatch, manifested as hy-
poxemia
Classification of PI (LF)according to functional parameters
Restrictive: TLC < 80%, FEV1/VC >85%
Obstructive: FEV1/VC)< 70%
Mixed
Classification of PI according to degree of severity
Degree РаО2, mmHg SaO2, %
Normal ≥80 ≥95
I 60–79 90–94
II 40–59 75–89
III <40 <75
Influence of hypoxemia
Central nervous system
Oxygen consumption of brain--3 ml/100g·min
If jugular vein PaO2 <20mmHg: unconsciousness, coma
PaO2 <20mmHg: irreversible damage to nerve cells in several minutes (4~5min)
Mild hypoxemia: impaired concentration, disorientation, hypomnesia
Severe hypoxemia: dysphoria, unconsciousness, coma
Cardiovascular system
Myocardium oxygen consumption: 10 ml/100g/min
Early stage of acute hypoxia–stimulation of sympathetic nerve→HR、BP、CO
Chronic hypoxia → small pulmonary arteries contraction → pulmonary hypertension— Cor pul-
monale
Respiratory system
