Control of breathing Flashcards
Most of the respiratory control is found where is the brain?
Rostral medulla
What accounts for the expiratory muscles rythm?
The Bötzinger complex
What accounts for the inspiratory muscles rythm?
The pre-Bötzinger complex
What accounts for the diaphragm rythm?
Nucleus tractus solitatus
Where are the O2 sensitive chemoreceptors?
Carotid body
What happens during hypercapnia (elevated CO2 in the blood)?
H+ doesn’t cross the brain/brain barrier. But when CO2 crosses and creates H+ with H2O. This is sensed and results in slow, deep respiration to augment tidal volume.
Feedback from airways and lungs comes from what?
Vegus nerves
Feedback from chest wall comes from what?
Muscle spindle
Golgi tendon organs
Proprioceptors from costovertebral joints
Feedback from upper airways comes from what?
Glossopharyngeal nerve and laryngeal nerves
What are the five causes of hyperventilation?
Metabolic Drugs Central nervous system Lung disease Psychogenic
What lung diseases cause hyperventilation?
Asthma
Fibrosis
Pulmonary edema
Pulmonary embolism
What are the metabolic causes of hyperventilation?
Acidosis
Liver disease
Hyperthyroidism
What are the causes of hypoventilation?
Metabolic Drugs Central nervous system Respiratory pump (chest wall abnormalities, neuromuscular disease) Parenchymal lung disease
What are the metabolic causes of hypoventilation?
Alkalosis
Hypothyroidism
Why administration of very high FiO2 might worsen PaCO2?
High FiO2 blunts hypoxic ventilatory drive
When high FiO2 reach alveoli, it undoes hypoxic vasoconstriction that directs the blood away from poorly ventilated (high PACO2) alveoli
