Respiratory Flashcards
Respiratory causes of SIADH
Malignancy and infective
1) SCLC
2) Pneumonia
3) TB
1st line investigations to diagnose asthma in adults
FeNO >50ppb or Eosinophil count >0.6x10^9
2nd line investigations to diagnsoe asthma in adults
1st) BDR:
- Pre test FEV1 increases by 12%/200ml or 10% of normal predicted value
2) If above is unavailable - PEFR BD for 14 days - >20% variability
3rd line investigation to diagnose asthma in Adults
Test for bronchial hyper-responsiveness
1st line investigation to diagnose asthma in Children aged 5-16YO
1) FeNO >35ppb
2nd line investigations to diagnose asthma in children aed 5-16 yo
1) BDR
- FEV1 increased by 12%/200ml or 10% of normal predicted value
2) If delay in above then PEFR BD for 14 days - >20% Variability
3rd line investigation to diagnose asthma in children aged 5-16yo
1) Skin prick test to dust mites and testing IGE Levels
- Dx if there is a rise in IgE levels and eosinophil count >0.5x10^9
Diagnosing asthma in children <5
1) Trial of inhaled corticosteroids
2) if attends A&E for wheeze x2 within 12 months then for specialist referral
Key clinical fatures to distinguish sarcoid from other DDX
Lupus Pernio - Blue/purpule nodules/plaques often around the nose/cheeks
Hypercalcaemia
X-ray - Bilateral hilar lymphadenopathy
(Generic)
Systemic features - Chronic cough, Weightloss, Fatigue, SOB, Joint pains
What is sarcoidosis
Systemic granulomatomous disease of UNKNOWN aetiology
Pathophysiology of hypercalcaemia in sarcoidosis
Granulomas activate macrophages which produce 1-alpha-Hydroxylase
This metabolizes 25,HydroxyVit D to Calcitriol (1,25 VitD)
This then increase Ca2+ reabsorbtion at the level of the kidneys
Investiagtions to Dx Sarcoidosis
CXR - Bilateraly Hilar Lymphadenopathy
Bloods - Hypercalcemia, Raised Serum ACE, Low PTH in response to Hypercalcaemia
Most common cause of COPD world wide
Smoking
What is a genetic cause of COPD
Alpha-1 Anti-trypsin deficiency
(Px <45 yo)
6 Causes of COPD
Smoking
A1-Antitrypsin deficiency
Occupational exposure:
- Coal
- Cadmium
- Cotton
- Grains
- Cement
Main cause of cystic fibrosis
Homozygousmutation in Delta F508 gene
- Derecruitment of CFTR protein which forms a channel that enables cl- ions to the membrane surface to enable thining of mucous
Six Indications of Lung transplantation in Cystic fibrosis
1) Severe exacerbations requiring ICU admission
2) Pulmonary Hypertension
3) FEV1 <30% of predicted
4) Recurrent Haemoptysis despite embolisation
5) Recurrent Pneumothorax
6) Recurrent exacerbations requiring Abx therapy
Contraindication to lung transplanatation in Cystic fibrosis
1) Colonisation with Burkholderia cepacia (B. Cepacia) - Poor outcomes/recurrent infections post op
What is the most common colonising bacteria in CF (Adults)
Pseudomonas Aureginosa (70%)
What is the most common colonising bacteria in CF patients (Children)
S. Aureus (75%)
Principles of management of CF patients - Non drug
1) BD chest physio and drainage
2) High calorie/High fat diet
3) Pancreatic enzyme supplementation
4) Avoid contact with other CF patients for prevention of spread of P.Aueriginosa/ B.Cepacia spread
5)Lung transplant - if indications are met
Drug maagement for CF patients with HOMOZYGOID delta F508 Mutations
ORKAMBI - Lumacaftor/Ivacaftor
Mechanism of action of orkambi
Lumcaftor - Recruits CFTR to membrane surface
Ivacaftor - potentiates CFTR to enable Cl- to pass through channel core
Pathophysiology of COPD/Emphysema
Overall imbalance between protease enzymes (Neutrophil elastase) and anti-protease (Alpa 1-anti trypsin)
Overall breakdown of elastin of the alveolar cell walls and permenant destruction of air space distal to terminal bronchioles
Results:
- Gas trapping
- Poor gas exchange
- Impaired elastic recoil
