Control of Lung Flashcards
What is the dorsal respiratory group
Inspiratory centre
Controller of inspiration
Set rate
What is the ventral respiratory group
Expiratory centre
Inactive during quiet breathing
Inhibit apneustic centre
What is apneustic centre
Stimualte activity in DRG
Inhibited by pulmonary afferents
What is pneumotaxic centre
Inspiratory off switch
Regulates depth and frenquency
What is DIVE
Dorsal inspiration Ventral expiration
How does C02 get pass the blood brain barrier
Co2 is highly lipid soluble can pass through the blood brain barrier
What are irritant receptors affect ventilations
Afferent receptors embedded within and beneath airway epithelium
Leads to cough: forecful expiration against closed glottis with sudden glottal opening leading to high velocity expulsion
What are stretch receptors
Excessive inflation of lungs which activates pulmonary stretch receptors
Afferent signals inhibit DRG and apneustic centre and stimulate pneumotaxic VRG
Inspiration inhibited and expiration stimulated
What are J receptors in the lung
Sensitive to oedema (swellign fluid and high pressure in pulmonary vessels) and pulmonary capillary engorgement
Increase breathing frequency
How does volitional apnoea happen
Increase in the starting level of oxygen
CO2 threshold for breathing is closer to o2 treshold for blackout
Why does the acidity of blood need to be regulated
Alter the 3D structure of proteins
Why did the dog not die after beign injected with acid
Has an enormous buffering capacity and can react almost immediately to imbalances
What is alkalaemia
High than normal pH of blood
What is acidaemia
Lower than normal pH of blood
What is alkalosis
Circumstances that will decrease protons and increase pH
What is acidosis
Circumstances that will increase portons and decrease pH
Why do you use ventilation to change the pH
Stimulate a RAPID compensatory response to change CO2 elimination and alter pH
Kidney stimulate a slow compensatory response
Why is having chemoreceptors in the aortic arch important
This is where most of the blood going to the brain comes from
What are the emotional changes to ventilation
Special senses are switched on which triggers an emotional response
Limbic system is involved which is close to brainstem
What happens during breathing during exercise
Efferents from primary motor cortex to skeletal musculature partially innervate medulla
Afferents from muscle and golgi tendon innervate medulla on the way to brain
What happens when skin gets cold on breathing
Immersion in cold water <10C induces hyperventilation/inspiratory gasp
due to superficial nerve endings in the skin
