Respiratory physiology 5 Flashcards
Why is glycosolated haemoglobin clinically important?
HbA1c can be used as an indicator of diabetes
Where is myoglobin found?
Cardiac and skeletal muscle
What 2 types of haemoglobin have a higher affinity for oxygen than adult haemoglobin?
Myoglobin and Foetal haemoglobin (HbF)
What are the 5 main types of hypoxia?
Hypoxaemic hypoxia (reduction of O2 diffusion)
Anaemic hypoxia (reduction of O2 capacity)
Stagnant hypoxia (inefficient pumping)
Histotoxic hypoxia (prevents utilising of O2)
Metabolic hypoxia (O2 demand by cells isnt met).
What nerves innervate the diaphragm?
Phrenic nerves (c3-c5)
What are 4 factors control respiratory centres?
Emotion
Voluntary over-ride
Mechanic-sensory input from thorax
Chemical composition of blood
Where are the respiratory centers located?
Medulla and pons
What does the dorsal respiratory group innervate?
Inspiratory muscles (via phrenic and intercostal nerves)
What are the 2 major groups of neurones within the respiratory centres?
Dorsal respiratory group (DRG)
Ventral respiratory group (VRG)
What does the ventral respiratory group innervate?
Creates a basal tone in expiratory muscles (tongue, pharynx, larynx)
To allow for slow, controlled expiration.
What are the 2 chemoreceptors?
Central and peripheral
What is the role of central chemoreceptors?
To detect changes in [H+] in CSF
What is hypercapnea?
Excess CO2 in the blood
What does hypercapnea cause?
Hyperventilation
Why can central chemoreceptors not respond in changes in plasma?
As ions cannot pass the blood-brain barrier.
