case 5 resp Flashcards
what type of cartilage exists in the trachea?
hyaline
which cells in the airway make mucus?
goblet cells
in which syndrome does mucociliary escalator not work?
kartagener syndrome
parasympathetic innervation of the airways has what 3 main functions?
- bronchoconstriction
- vasodilation
3 mucus secretion
sympathetic innervation of the airways has what 3 main functions?
- bronchodilation
- vasoconstriction
- modulation of cholinergic transmission
what is the relationship between airway resistance and airflow?
high resistance = low airflow
structurally how can an airway have increased resistance?
purely structurally
long airway + small radius = high resistance
low amount of what protein will cause neonatal respiratory distress syndrome?
function of this thing?
surfactant
surfactant stops alveolar collapse
how does compliance change in emphysema?
high compliance
how does compliance change in pulmonary fibrosis?
low compliance
what happens to airways in asthma (structurally)?
constricts
is this condition obstructive or restrictive?
asthma
obstructive
is this condition obstructive or restrictive?
pulmonary fibrosis
restrictive
is this condition obstructive or restrictive?
emphysema
obstructive
is this condition obstructive or restrictive?
motor neurone disease
restrictive
Va:Q ratio
what does Va stand for?
what does Q stand for?
Va - ventilation
Q - perfusion
what is the anatomical dead space?
what is the value of the Va:Q ratio in the dead space?
where there is no capillary perfusion but there is ventilation.
infinity
how can an anatomical dead space be created pathologically?
pulmonary embolism
in a right to left shunting of blood what is Va:Q ratio?
how can this shunting occur in the lungs pathologically?
-2
0
occluded airway or
fluid filled alveoli (i.e. pulm oedema)
how does perfusion change moving down the lung?
increases
how does ventilation change moving down the lung?
increases
in a normal alveoli, how much O2 is there in mmHg?
100 mmHg
in a normal alveoli, how much CO2 is there in mmHg?
40mmHG
in a normal alveoli, how much O2 is there in kPa?
13.3kPa
in a normal alveoli, how much CO2 is there in kPa?
5.3kPa
if there is low Va (ventilation) in a certain area of the lung how does pulmonary vasculature react to stop V:Q matching?
why does it do this?
pulmonary vasculature vasoconstricts
stop Va:Q mismatching
someone is at high altitude and gets global lung hypoxia.
how does pulmonary vasculature react in this situation?
what complication will this lead to?
-2
global pulmonary vasculature vasoconstricts
pulmonary HTN –> R.sided heart failure
where is the central control area for breathing in the brain?
what is this centre called?
medulla, brain
medullary respiratory centre
what two receptors feed the
medullary respiratory centre
information?
central chemoreceptors &
peripheral receptors
of the two receptors feeding the medullary respiratory centre with info:
which is sensitive to CO2 only?
central chemoreceptors
of the two receptors feeding the medullary respiratory centre with info:
which is sensitive to O2 and CO2?
peripheral receptors
of the two receptors feeding the medullary respiratory centre with info:
which has a fast response time?
peripheral receptors
of the two receptors feeding the medullary respiratory centre with info:
which has a slow response time?
central chemoreceptors
where are the central chemoreceptors found?
ventrolateral surface of medulla
where are the peripheral chemoreceptors found?
near carotid and aortic arteries
the medullary respiratory centre is most sensitive to what:
hypoxia
hypercapnia
or both
both - synergy of hypoxia & hypercapnia increases minute ventilation the most
what are the functions of the lung?
-6
blood reservoir
make ACE
bring blood into contract with alveoli (gas exchange)
source of heparin (blood thinner)
source of thromboplastin (blood clotter)
protects body from emboli vis mechanical filtration
how do pulmonary arterioles differ from systemic arterioles?
-4
thinner
less elastin
less smooth muscle
more compliant
what happens to pulmonary arterial pressure moving up the lung?
decreases
where is ventilation best in lung, bottom or top?
bottom
why does top of lung have worst ventilation?
top of lung has more negative pressure - so alveoli keep expanded - thus less ventilation
as you move up the lung, blood flow through the pulmonary vasculature only occurs when?
why
in systole
because pulmonary arterial pressure decreases moving up the lung
in which pathologies will there be no blood flow through pulmonary vasculature?
- 2 main ones
why?
- step by step
sepsis, massive haemorrhage
because these pathologies have less blood volume, so less BP, so less pulmonary arterial pressure, so blood not pushed through vasculature/ can not overcome alveoli pressure
for blood to move through pulmonary vasculature what must the pulmonary arterial pressure overcome?
-2 things
alveoli pressure
pulmonary venous pressure
there is an over ventilated area in the lung.
how does lung respond to minimise V/Q mismatch?
bronchoconstriction
there is local ischaemia in an area of the lung.
how does lung respond to minimise V/Q mismatch?
bronchoconstriction
there is local hypoxia in an area of the lung.
how does lung respond to minimise V/Q mismatch?
vasoconstriction
if there is increased perfusion pressure (i.e. more blood flow in the lung) say during exercise.
what adaptations does the lung have to stop pulmonary vascular resistance in response to the increased perfusion pressure?
-2
if the lung did not adapt what complications will develop?
-2 (they are linked to each other)
vessels distend
recruits dormant pulmonary capillaries
pulm HTN –> R.sided heart failure
vasoconstriction will cause what to happen to lumen size?
what does this increase in the airways?
what complication will now occur?
decreases/narrower
resistance
pulm HTN
pulmonary HTN will eventually lead to what major complication?
R.sided heart failure
cor pulmonale
Right ventricular failure due to a lung problem is called what?
how will the RV adapt to increased pulmonary HTN?
cor pulmonale
RV muscle becomes thicker
what happens to cardiac output in cor pulmonale eventually?
↓CO
where does the oedema occur in R.sided heart failure?
systemic oedema
where does the oedema occur in L.sided heart failure?
pulmonary oedema
features or cor pulmonale (basically R.sided heart failure)
cyanosis SOB ascites raised JVP big neck and veins swollen ankles
drug group to get rid of fluid in cor pulmonale?
diuretics
restrictive lung diseases can be divided into what two categories?
pulmonary &
extra-pulmonary
which lung cell type produces surfactant?
type 2 alveolar cells
which cells in the lung make collagen?
fibroblasts
which cells in the lung make elastin?
fibroblasts
define fibrosis
tissue scars and thicken (too much collagen)
CT of lung with pulmonary fibrosis shows what hallmark feature?
honeycomb appearance
symptoms & signs of pulmonary fibrosis?
-5
dry cough SOB finger clubbing peripheral cyanosis fine end inspiratory crackles
with pulmonary fibrosis, what decreases on spriometry?
FVC, functional vital capacity
extra-pulmonary restrictive lung disease examples?
-5
obesity
scoliosis/ kyphosis
motor neuron disease
pleural effusion
why does pleural effusion cause restrictive lung disease?
extra fluid (between parietal and visceral) compresses on lung
define FEV1?
air you blow out in 1 second
define FVC?
total volume of air blown out
define respiratory failure?
pulmonary gas exchange is insufficient and hypoxaemia occurs (with or without hypercarbia)
what are the two types of respiratory failure?
type 1: hypoxaemia only
type 2: hypoxaemia and hypercarbia
what is the cut off value for hypoxaemia?
- kPa
- and mmHg
PaO2 <8kpa/ 60mmHg
what is the cut off value for hypercarbia?
- kPa
- and mmHg
PaCO2 >7kPa/55mmHg
mainstay (immediate) treatment for hypoxaemia?
give O2
which respiratory failure occurs when there is ventilatory failure?
define this type of respiratory failure?
type 2
type 2: hypoxaemia and hypercarbia
mainstay (immediate) treatment for type 2 respiratory failure?
ventilation
high CO2/ hypercarbia symptoms
drowsy
sleep in day
confused
headache
high CO2/ hypercarbia sign at the hand?
hand flap
why should you not over oxygenate a pt with hypercarbia which is ultimately result of ventilatory problem?
over oxygenation can reduce their ventilatory drive since low O2 tells medulla to ventilate more.
what electrolyte is lacking in cystic fibrosis mucus?
what effect does this have on mucus viscosity?
Cl-
mucus thick
how does peripheral nervous system affect mucus production?
more PNS = more mucus
2 types of COPD?
emphysema
chronic bronchitis
pathophysiology of chronic bronchitis?
sub mucosal glands and goblet cells hypertrophy –> excess mucus made –> can not get rid of all mucus –> get infected again –> more inflammation and thus more mucus made again.
main way smoking causes chronic bronchitis?
paralyses mucociliary escalator
emphysema pt use what type of breathing?
why?
pursed lip breathing
created negative pressure to stop airways collapsing
which protein is destroyed in emphysema?
elastin
step by step outline how COPD can cause cor pulmonale and systemic oedema?
sever COPD –> lung hypoxic –> pulmonary vasculature constrict –> more pulmonary resistance –> pulmonary HTN –> pressure on right ventricle, eventually fails –> cor pulmonale –> back pressure in systemic venous now so fluid pushed out
obstructive value on spirometry?
<0.7
restrictive value on spirometry?
> 0.7
how does sputum become green in infection?
neutrophils go to fight infection –> neutrophil rupture –> ooze out myeloperoxidase –> myeloperoxidase make sputum green
what score is used for pneumonia severity?
CURB65
what does CURB65 stand for?
confusion urea rep rate BP 65+ age
define pneumonia?
lung tissue itself infected
hallmark feature of bronchiectasis?
dilated airways filled with mucus
hallmark feature of bronchiectasis on CXR?
signet ring
main cause of bronchiectasis>
infection
what test is used to check for CF?
sweat chloride test
pt has bronchiectasis.
what is head on ausculation?
coarse crackles
what test is used to estimate left atrium pressure in LV heart failure?
pulmonary capillary wedge pressure
why is it risky to give lots of opioids in pt with type 2 resp failure?
opioids diminish resp drive
pt has hypercapnia.
how will headache severity change during day?
headache worst in morning
how do you treat infant respiratory distress syndrome?
cPAP
which pneumonia, hospital or community has higher mortality?
hospital
