Respiratory π« Flashcards
describe type 1 resp failure
low p02 <8 kPa
normal pco2
Ventilation - perfusion mismatch
describe type 2 respiratory failure
low PaO2 < 8kPa
high PaCO2 > 6 kPa
alveolar hypoventilation - fail to effectively oxygenate and blow off co2
what is FEV1
forced expiratory volume in 1s
volume exhaled in first second after deep inspiration and forced expiration
what is FVC
total volume of air that the patient can forcibly exhale in 1 breath
what would spirometry tell us in an obstructive resp condition
FEV1 reduced - <80%
FVC also reduced slightly but not to same extent
so FEV1/FVC ratio is reduced - <0.7
what would spirometry tell us in a restrictive lung disease
FEV1 and FVC both reduced so normal ratio
examples of restrictive lung diseases
fibrosis
obesity
myasthenia gravis
lungs canβt take as much volume but airway is not narrowed so expiration is normal speed
examples of obstructive lung diseases
asthma
COPD
cystic fibrosis
airways narrowed so canβt get air out as quickly but lung tissue is still stretchy so can take in normal volume
presentation that would suggest asthma
episodic symptoms
cough worse at night
dyspnoea
expiratory wheeze
hx of other atopic conditions such as eczema
family hx
Ix and Dx of asthma
feNO testing + spirometry with bronchodilator reversibility testing => gold standard
feNO will be raised
mx of asthma
SABA - reliever
ICS (inhaled corticosteroids) - preventer
LTRA - oral med
LABA - long term reliever
MART - preventer and reliever
LAMA
mx of asthma ladder - NICE guidelines
SABA
SABA + low dose ICS
SABA + ICS + LTRA
SABA + ICS +LTRA + LABA
consider changing to MART
increase ICS to moderate dose
signs of moderate acute asthma
PEF >50-75%
SpO2 >92%
speech normal
RR<25
pulse <110
signs of acute severe asthma
PEF 35-50
SpO2 > 92
canβt complete sentences
RR|>25
pulse > 110
signs of life threatening asthma
PEFR <33
SpO2 <92
PaO2 <8kPa
normal C02
silent chest, cyanosis
arrhythmia or hypotension
exhaustion altered consciousness
treatment of acute moderate asthma
B2 bronchodilator
if no improvement
salbutamol via nebuliser
give prednisolone
treatment of acute severe asthma
oxygen
B2 bronchodilator
prednisolone or IV hydrocortisone
what is COPD
characterised by irreversible obstruction of airways
almost always caused by smoking
umbrella term for chronic bronchitis and emphysema
presentation of COPD
productive cough
chronic SOB
wheeze
recurrent resp infections
severe : cor pulmonale
Ix COPD
spirometry reduced fev1/fvc ratio <0.7
chest x ray : hyperinflation, bullae, flat hemidiaphragm
FBC: secondary polycythaemia
mx COPD
smoking cessation + pneumococcal and flu vaccine
bronchodilator therapy
Long term oxygen therapy - non smokers + severe COPD
acute exacerbation of COPD signs and symptoms
increased SOB
cough
wheeze
increased sputum
hypoxia
confusion
mx acute exacerbation COPD
OABC
Oxygen - high flow
Antibiotics - amoxicillin or clarithomycin
Bronchodilators
Corticosteroids - oral prednisolone or IV hydrocortisone
sx and signs of lung cancer
persistent cough, SOB, haemoptysis
weight loss
finger clubbing
lymphadenopathy