Integrated control of breathing Flashcards
What are the steps involved in respiratory acidosis?
- Decreased ventilation
- Increased PACO2
- Increased PaCO2
- Increased [H+] which results in a decreased pH
What does a decrease in pH and an increase in PACO2 result in?
- Increase in chemoreceptor feedback
- Increase in respiratory rate
What must decrease in the event of chronic hypo-ventilation?
In the event of hypo-ventilation,HCO3- excretion must decrease to maintain normal pH
What are the causes of hypoventilation?
- Airway obstruction
- Aphyxia, choking
- Obstructive sleep apnoea
- Increased airway resistance(Asthma, COPD)
What are other causes of hypoventilation despite the fact that the airway is clear?
- Drug overdose
- Stroke
- Neuromuscular problems
Steps involved in respiratory alkalosis
- Increased ventilation
- Decreased PACO2
- Decreased PaCO2
- Decreased [H+] which results in an increased pH
What does a decrease in PACO2 and an increase in pH result in?
- Decrease in chemoreceptor feedback
- Decrease in respiratory rate
What must increase in the event of chronic hyperventilation?
HCO3- excretion must increase to maintain normal pH
What are the causes of hyperventilation?
-Anxiety
Steps involved in hyperventilation(Anxiety)
- Increased ventilation without increased metabolic demand
- Hyperventilation leading to decreased PaCO2
- Results in respiratory alkalosis
What are the causes of respiratory alkalosis?
-Altitude
-Theres an increase in alveolar ventilation to maintain
PAO2 and PaO2
-Theres increased ventilation which results in decreased
PaCO2
-Therefore results in respiratory alkalosis
What are the causes of metabolic acidosis?
- Addition of [H+]
- Decreased absorption of HCO3-
- Increased excretion of HCO3-
- All the above result in a decrease in [HCO3-]
Causes of metabolic acidosis(Lactic acidosis(sepsis))
- Infection
- Pathological immune response
- Septic shock
- Decreased oxygen delivery to tissue
- Increased lactic acid production and decrease in pH
- Therefore this results in respiratory compensation to increase O2 delivery and increase lactic acid conversion
What are other causes of metabolic acidosis?
- Diabetic ketoacidosis
- Diarrhoea
- Renal faliure
What are the causes of metabolic alkalosis?
-Removal of H+
-Increased absorption of HCO3-
Decreased excretion of HCO3-
-Results in an increase in [HCO3-]
