transition - physiology

Question 1

where is resp rhythm generated

Answer 1

medulla

Question 2

where are the peripheral chemoreceptors situated

Answer 2

carotid bodies, aortic bodies

Question 3

what do the peripheral chemoreceptors sense

Answer 3

oxygen co2 and h+ in the BLOOD

Question 4

where are central chemoreceptors situated

Answer 4

surface of medulla

Question 5

what do central chemoreceptors respond to

Answer 5

H+ conc of the CSF (csf separated from blood by BBB)

Question 6

what is hypoxic drive of respiration via

Answer 6

peripheral chemoreceptors

Question 7

when is hypoxic drive important

Answer 7

in chronic co2 retention (COPD)

Question 8

what is H+ drive of respiration via

Answer 8

peripheral chemoreceptors

Question 9

what is the function of H+ drive of respiration

Answer 9

major role in adjusting acidosis by the addition of non-carbonic acid H+ to blood

Question 10

Loss of transmural pressure gradient across the lungs?

Answer 10

pneumothorax

Question 11

inspiratory muscles

Answer 11

diaphragm contraction and external intercostals to lift ribs and move out sternum

Question 12

accessory muscles

Answer 12

sternocleidomastoid and scalenus

Question 13

muscles of active inspiration

Answer 13

internal intercostals and abdominal muscles

Question 14

what keeps alveoli open

Answer 14

transmural pressure gradient, pulmonary surfactant and alveolar interdependence

Question 15

parasymp effect on lungs

Answer 15

bronchoconstriction

Question 16

sympathetic effect on lungs

Answer 16

bronchodilation

Question 17

is what condition is the v/q ratio high

Answer 17

PE = decrease perfusion, but normal ventilation

Question 18

heart failure shifts frank-starling curve what way

Answer 18

right

Question 19

what factors shift oxygen haemoglobin dissociation curve right - and what does that mean

Answer 19

inc pCO2
inc H+ (dec pH)
inc 2,3-DPG
inc temp

= decreased affinity for O2 to bind to haemoglobin

Question 20

cardiac output calculation

Answer 20

CO = SV x HR

Question 21

stroke vol calculation

Answer 21

SV = EDV - ESV

Question 22

what determines preload

Answer 22

EDV

Question 23

left sided HF features

Answer 23

pulmonary oedema and SOB

Question 24

what is the pO2 value in anaemia

Answer 24

normal

Question 25

maximum volume of air that can be inspired at the end of a normal quiet expiration

Answer 25

inspiratory capacity

Question 26

what one is the green one

Answer 26

normal

Question 27

what one is red

Answer 27

asthma

Question 28

what one is blue

Answer 28

COPD

Question 29

what is the COPD spirometry confirmed diagnosis

Answer 29

post bronchodilator FEV1/FVC<0.7

Question 30

Question 1: functional residual capacity: A usually increased in obese people B measured by spirometry C decreased in COPD D normally 40% of total lung capacity E approximately 20% vital capacity

Answer 30

= D FRC: expiratory reserve + residual volume FRC decreased in obese people due to diaphragm being pushed up by fat Cannot measure FRC by spirometry because you cannot take residual volume out of lungs COPD- in emphysema FCR is increased

Question 31

Question 2: patient with pulmonary fibrosis, FEV1/FVC% is likely to be A 45 B 50 C 60 D 65 E 85

Answer 31

Ans: 85

Question 32

Question 3: 67 YEAR OLD, SMOKES SINCE TEENS AND BEEN DIAGNOSED WITH COPD. His FEV1/FVC is <70% and his airflow limitation is moderate. What is his post bronchodilator FEV1 (% predicted of normal) likely to be>? A 20% B 40% C 60% D 80% E 90%

Answer 32

Ans: 60

Question 33

Question 4: 23 y woman sees GP about intermittent breathlessness. Feels breathless when she's in a crowded room. When she's breathless she also notices numbness and tingling around mouth. FBC reveals Hb 10.5g/dl A increased work of breathing due to reversible airways obstruction B increased central and autonomic arousal C reduced 02 carrying capacity of blood D stimulation of peripheral chemoreceptors E reduced SA for gas exchange

Answer 33

Ans: B Tingling round mouth- co2 out from ventilation so blood ph increases ie respiratory alkalosis Calcium decreased

Question 34

Question 5: what is correct about normal lungs A low po2 causes pulmonary vasoconstriction B larger airways are supplied by pulmonary circulation C beta 1 agonists cause bronchodilation D parasympathetic stimulation causes bronchodilation E SA for gas exchange remains constant in absence of disease

Answer 34

Ans: A In lungs low po2 causes vasoconstriction, would rather perfuse more well ventilated areas Large airways have their own blood supply via bronchiole arteries B2 agonists cause bronchodilation Parasympathetics cause bronchoconstriction SA changes when you exercise, hyperventilate

Question 35

Question 6: 72 y/o woman has had 2 MIs in the past and a recent echocardiogram has shown moderately impaired LV function. She has SOB worse at night A increased alveolar surface tension B increased work of breathing due to reversible airways obstruction C reduced o2 carrying capacity of blood D reduced pulmonary compliance and impaired gas diffusion E stimulation of central chemoreceptors

Answer 35

Ans: D Oedema affects pulmonary compliance and gas exchange

Question 36

Question 7: in patient with COPD A inspiration more difficult than expiration B dynamic airway compression likely to occur during active expiration C presence of emphysema will help alleviate dynamic airway compression D o2 saturations should be maintained near 100% if patient is retaining co2 E dynamic airway compression likely to occur during inspiration

Answer 36

Ans: b

Question 37

Question 8: which is correct about patient with emphysema A gas exchange unaffected B work of breathing decreased C pulmonary compliance increased D total lung volume decreased E FEV1/FVC ratio increased

Answer 37

Ans: c Work of breathing increases with emphysema

Question 38

Question 9: for TPX: A intra-pleural pressure becomes more negative B trachea can deviate to same side C patient likely to be hypotensive D breath sounds increased E chest pain not a symptom

Answer 38

Ans: c INTRA-PLEURAL PRESSURE BECOMES MORE + IN EQUALIBRIUM WITH LUNG OR OUTSIDE PRESSURE

Question 39

Question 10 Previous fit 22 year old has been unwell for 2 days, px with cough productive of green sputum, fever, SOB. Her PO2 is 8.2kPa. What are her saturations likely to be? A 70 B 75 C 80 D 90 E 98

Answer 39

ANS: D Function residual capacity- normally 40% of lung capacity

Question 40

Answer 40

a - DKA

Question 41

Answer 41

c

Question 42

Answer 42

B acute MI with pul oedema nitrate infusion dilates peripheral veins and decreases preload

Question 43

Answer 43

D thyroid function tests

Question 44

Answer 44

A

Question 45

Answer 45

= a Tingling around mouth and fingers = respiratory alkalosis

Question 46

Answer 46

E

Question 47

Answer 47

D