Respiratory 1 Flashcards
label the diagram
where does gas exchange take place?
alveoli
Large SA to maximise gas exchange
describe the epithelium of the alveoli?
very thin squamous epithelium called type 1 alveolar cells
what is special about type 1 alveolar cells ?
minimise the the distance between th inhaled gases and ythe blood vessels that will then absorb those gases to carry around the body
what are type 2 secretory alveolar cells?
secrete a surfactant
reduces water tension in lungs which prevents the existing fluid in lungs to prevent alveoli from opening up
where do we find pseudo stratified columnar epithelium ?
in bronchioles and bronchi
what is special about the pseudo stratified columnar epithelium?
has cilia - waft mucus up to pharynx so it can be coughed out or swallowed
- cilia and mucus act as barriers against infections
what is the function of the lungs
o2 absorption and co2 removal
gas exchange by diffusion
what are 02 and co2 levels detected by?
chemoreceptors in aortic arch and carotid artery
what happens when there is increase in cp2 and low o2
- signal to brain to increase rate and depth of breathing so inhale more 02 and exhale more c02
why is also having PH receptors important In identifying co2 levels?
c02 makes blood more acidic a sit creates carbonic acid
how is excess c02 and acid base balance controlled?
by breathing
what happens if there Is load of c02 in blood?
- more acid is detected by ph receptors increase in ventilation in lungs to remove c02 and restore blood ph
how many ppl are diagnosed from asthma per yr?
160000
in adults or children
what is asthma
inflammation in bronchioles causes the muscles around them to contract and thus narrowing the airways
mucosa of airways becomes oedematous and blocked up with fluid
XS mucus production
what is severe asthma
lasting chronic inflammation
preventative medication needed
what are the triggers for asthma
- early in morning or night
- allergy pollution
- inhaling smoke or second hand smoke
- cold weather
- infections
- NSAIDS
what does atopic mean?
ppl who have asthma who have allergies and are often suffering from hay fever and eczema as they produce XS IgE
list the things we use to manage asthma ?
what do short acting beta 2 agonist do in the management of asthma?
- reliever = salbutamol or tabultailne - use these for asthma attack - beta 2 agonist
- they dilate airways by relaxing smooth muscle
- not speicif to airways receptors they will act on other beta receptors cause sensation of palpitations as beta agonist act on sympathetic pathway and stimulate heart to beat faster
- they thicken saliva and increase caries
if reliever isn’t working what do doctors prescribe?
preventative inhaler
- inhaled corticosteroid
- reduce airway inflammation
- end in azone or anide
- can lead to oral thrush
- advise pt to use spacer or wash inhaler regularly or rinse mouth after use
what will the doctors prescribe if the inhaled corticosteroid doesn’t work?
leukotriene receptor antagonist
tablet eg. montelukast which dilates airwaves and acts as an anti inflammatory
what will doctors prescribe if leukotriene receptor antagonist don’t work ?
- long acting beta 2 antagonists
- same mechanism as deliver inhaler
- but lasts for long time
- starts alongside with preventer and reliever
- eg. salmetorol
what is MART?
maintenance and reliever therapy
- combination of inhalers
- inhaler for poorly controlled asthma
- has reliever and preventer drug in it
eg. foster
what happens if MART doesn’t work?
long acting muscarinics
- block bronchoconstruction
eg. iprotropium , theophylline tablets (anti inflammatory, dilate airways)
prednisolone (long term or rescue med for bad flare up)
what happen if our pt is on more Etna just beta 2 agonist or more than three drugs for asthma?
- if thy have an asthma attack need to call ambulance
how do we manage acute exacerbation of asthma?
what signs will a pt show if they’re experiencing asthma attack ?
Airways - tight chest and short breath and wheeze = due to bronchial contraction impeding ventilation
Cough= due mucus in oedema of mucosa
siting up right = to compensate for feeling shortness of breath
increase respiratory rate = due to narrow airways
tensing of sternocleidomastoid = using accessory muscles to help with breathing
high hr = in attempt to deliver limited oxygen supply
eventually pt becomes hypoxic and will decompensate
what can asthma cause in the long run?
permanent airway obstruction due to repeated exacerbations can cause fibrosis and inflammation in bronchioles
- we can detect this by using a peak flow meter
what does a peak flow meter do?
measures maximum rate at which a pt can exhale air
limited in asthma pt due to bronchial constriction
do this in ABCDE
what questions to ask for asthmatic pts?
what is COPD?
airway obstruction
cigarettes smoke causes damage to bronchi and alveoli
cells produce XS mucus to clear smoke
this causes mucus producing cells to hypertrophy therefore more and bigger mucus producing cells
this is called chronic bronchitis which is long term inflammation
damage to walls of alveoli = they merge together and cause emphysema
COPD = encompass either or both of these conditions
what is the difference between asthma and COPD ?
asthma is episodic
COPD is chronic
asthma bronchoconstriction is reversible whereas COPD bronchoconstriction is irreversible
what meds do we use to treat COPD?
- short acting beta agonist
- corticosteroid inhaler
- carbosystine - thins XS mucus so easy to clear
what does barrel chested mean?
lungs appear expanded at rest
struggle exhale gas from lungs
list the symptoms of severe COPD
why do pts purse their lips ?
increase pressure inside the thorax to help them exhale as exhalation comes from a pressure gradient from lungs to the outside
why are pts on long term 02 therapy?
as they become chronically hypoxic
why does right side heart failure occur?
increase resistance blood flow thru lung due to tissue damage which puts strain on RHS of heart leads to oedema
what are the different types of respiratory failure?
type 1 - hypoxia
type 2 - hypercapnia
what is type 1 respiratory failure?
- low 02 stats
- normal c02 levels
due to impaired gas exchange
what is type 2 rest failure?
high c02 in blood due to diffulcy ventilating
we see this in COPD
what happens if we give COPD pts too much 02 in an exacerbation?
- decrease in RR and depth so less co2 is exhaled
- O2 in excess, move blood to areas of lungs, hard to remove CO2, displace CO2 by where its buffered by haemoglobin so becomes more acidic causing
- pt appears Flushing, headache, tremor, confusion, drowsy as reduced respiratory rate so reduced CO2 removal
why does hyperventilation happen?
Anxiety- increase depth and respiratory rate therefore blowing off CO2 causing respiratory alkalosis - responsible for tingling sensation an slight headed ness
can be managed my breathing techniques
not low o2 but low co2
COPD in dentistry?
- access routes in building
- lying flat makes breathing difficult
- dry mouth from pursed lips
- use BNF to check drug interxn
