Respiratory Failure Flashcards
What is a respiratory infection?
Syndrome of inadequate gas exchange due to dysfunction of one or more components of the respiratory system
Where does a respiratory infection affect?
Nervous system
CNS/Brainstem
Peripheral nervous system
Neuro-muscular junction
Respiratory muscle
Diaphragm & thoracic muscles
Extra-thoracic muscles
Pulmonary
Airway disease
Alveolar-capillary
Circulation
In men and women, what is the biggest risk factor for chronic respiratory disease?
Males: Smoking biggest risk factor
Women: Household air pollution from solid fuels
How does ventilation across the lung work?
PPL is more negative (-8 cmH2O)
Greater transmural pressure gradient (0 vs. -8)
Alveoli larger and less compliant
Less ventilation
PPL is less negative (-2 cmH2O)
Smaller transmural pressure gradient (0 vs. -2)
Alveoli smaller and more compliant
More ventilation
How does perfusion across the lung work?
Lower intravascular pressure (gravity effect)Less recruitment
Greater resistance
Lower flow rate
Higher intravascular pressure
(gravity effect)
More recruitment
Less resistance
Higher flow rate
Describe oxygen transport when loading in the lungs?***
Describe the pulmonary transit time?
Ventilation perfusion matchin?
Describe the structural properties of lung tissue*
COMPLIANCE
The tendency to distort under pressure
πͺπππππππππ= βπ½/βπ·
ELASTANCE
The tendency to recoil to its original volume
π¬ππππππππ= βπ·/βπ½
What is an acute respiratory disorder
Pulmonary: Infection, aspiration, Primary graft dysfunction (Lung Tx)
Extra-pulmonary: Trauma, pancreatitis, sepsis,
Neuro-muscular: Myasthenia/GBS
What is a chronic respiratory disorder
Pulmonary/Airways: COPD, Lung fibrosis, CF, lobectomy
Musculoskeletal: Muscular dystrophy
What is an acute on chronic respiratory disorder
Infective exacerbation
COPD, CF
Myasthenic crises
Post operative
Lung volumes and capacities?*
How to work out minute ventilation?
Gas entering and leaving the lungs
Tidal volume x Breathing frequency
How to work out alveolar ventilation?
(Tidal volume - Dead space) x Breathing Frequency
What is the physiologic classification in terms of type I?
Type I or Hypoxemic (PaO2 <60 at sea level):
Failure of oxygen exchange
-Increased shunt fraction (Q S /QT )
-Due to alveolar flooding
-Hypoxemia refractory to supplemental oxygen
What is the physiologic classification in terms of type II?
Type II or Hypercapnic (PaCO2 >45): Failure to
exchange or remove carbon dioxide
-Decreased alveolar minute ventilation (V A )
-Dead space ventilation
What is the physiologic classification in terms of type III?
Type III Respiratory Failure: Perioperative respiratory
Failure
-Increased atelectasis due to low functional residual capacity
(FRC) with abnormal abdominal wall mechanics
-Hypoxaemia or hypercapnoea
-Prevention: anesthetic or operative technique, posture,
incentive spirometry, analgesia, attempts to lower intra- abdominal pressure