resp

Question 1

what physiological change would occur in the lungs in response to low oxygen saturation ?

Answer 1

the pulmonary arteries vasoconstrict

> a fall in the partial pressure of oxygen in the blood leads to vasoconstriction of the pulmonary arteries, this allows blood to be diverted to better aerated areas of the lung and improves the efficiency of gaseous exchange

Question 2

a man walks into ICU following an emergency abdominal aortic aneurysm repair, he develops abdominal pain and diarrhoea and is profoundly unwell , what are his ABGs likely to show ?

Answer 2

metabolic acidosis - secondary to a mesenteric infarct

Question 3

controls of ventilation

Answer 3

• peripheral chemoreceptors are located in the bifurcation of the carotid arteries and arch of the aorta
• central chemoreceptors respond to increased hydrogen ions in brain interstitial fluid to increase ventilation
• the respiratory centres control the rate and depth of respiration
• involuntary control of respiration is from the medulla and pons
• irritant receptors cause bronchospasm

Question 4

what are the three respiratory centres

Answer 4

• medullary resp. centre
• apneustic centre
• pneumotaxic centre