Respiratory Flashcards
(47 cards)
What are the causes of bronchiectasis?
Congenital - impaired microcilary transport
Cystic fibrosis, Young’s syndrome, primary ciliary dyskinesia, Kartagener’s syndrome
Acquired - Post infection: measles, pertusis, bronchiolitis, pneumonia, TB, HIV Bronchial obstruction: foreign body, tumour Allergic broncopulmonary aspergillosis, Hypogammaglobulinaemia, RA UC Idiopathic
What is bronchiectaisis?
Abnormal permanently dilated airways with inflamed thickened bronchial walls.
On CT see signet ring sign and on CXR see tramline and ring shadows
What are the clinical features of bronchiectasis?
Persistent cough, copious purulent sputum, intermittent haemoptysis,
Clubbing, coarse inspiratory crackles, wheeze,
Complications - pneumonia, pleural effusion, pneumothorax, cerebral abscess, amyloidosis
Describe the illness cystic fibrosis:
Autosomal recessive condition
Mutation in 7q31.2 results in defect in cystic fibrosis transmembrane conduction regulator (Chlorine channel)
Failure of opening of the channel when cAMP increases in the cells, leads to a decrease in chlorine excretion into the airway lumen. This leads to an increase in the reabsorption of Na into the epithelial cells, which is followed by water, so there is less water excreted which increases the viscosity of the secretions.
The result of the increased viscosity of the secretions is an increase in respiratory infections leading to chronic lung disease, infections and bronchiectasis.
Patients also have pancreatic insufficiency leading to malnutrition and diabetes
What are the clinical features of cystic fibrosis at the different ages?
Neonate - Meconium ileus
Children and young adults -
Respiratory: cough, wheeze, chronic infections, etc Pts start with staph aureus and strep pneumonia infections and then develop chronic pseudomonas and burkholderia cepacia later on.
GI: energy needs increase by 130%, pancreatic insuffieceny requires enzymes, diabetes, GI obstruction more common
Other: infertility, osteoporosis, arthritis, vasculitis,
What result on the sweat test would diagnosis CF?
> 60mmol/l with chloride > Sodium
What are the three characteristics of asthma?
Airflow limitation - reversible
Airway hyperesponsiveness
Bronchial inflammation : T and Mast cells, plasma exudation, oedema, muscle hypertrophy, matrix deposition, mucus plugging
There are three factors that contribute to the airway narrowing:
- bronchial muscle contraction
- mucosal swelling
- increased mucus production
What are the steps in asthma management?
Step 1: inhaled short acting B2 agonist
Step 2: Add inhaled corticosteriod 200-800 ug/ day
Step 3: Add inhaled long acting B2 agonist
if good response from LABA cont
if response to LABA but inadequte control increase steroid to 800ug if not yet on
if no response to LABA stop it and increase steroid. if still inadequate consider adding leukotriene receptor agonist or SR theophylline
Step 4: increased steroid to 2000ug/day
think of adding a fourth drug (leukotriene receptor agonist, SR theophylline or B agonist tablet
Step 5: use daily steroid tablet - refer for specialist care
What are the different levels of acute asthma?
Moderate asthma:
increasing symptoms
PEF >50 - 70% best or predicted
Severe asthma: PEF 33-50% best or predicted RR >25 HR >110 inability to complete full sentences
Life threatening asthma: PEF <8 normal pCO2 Silent chest Cyanosis Poor respiratory effort Arrhythmia Exhaustion, altered LOC Hypotension
Near Fatal:
Increased PaCO2
How do you treat acute asthma?
Oxygen:
Maintain stats between 94-98%
Use oxygen to drive nebuliser
Salbutamol:
2.5 - 5mg nebuliser - back to back if not helping
Can use IV but only in patients not responsive to nebs
Ipratropium Bromide:
0.5 mg neb 4-6hrly
Steroids:
100mg IV hydrocortisone or 30mg pred PO STAT
continue 40-50mg pred for 5 days post attack
Magnesium sulphate
IV 1.2-2g over 20mins (need to be on cardiac monitor)
When do you need to refer an asthmatic patient to ITU?
ANY ONE WHO HAS ACUTE OR LIFE THREATENING ASTHMA
need to refer early!!
What is a significant diurnial variation when diagnosing asthma?
> 20% difference in peak flow on >3days a week for 2 weeks.
What are the three commonest causes of a chronic cough with a normal chest xray?
Asthma
Sinusitis and post nasal drip
Reflux oesophagitis
What are the differences between community acquired, hospital acquired and aspiration pneumonia?
CAP - pneumonia developed in the community
Strep pneumoniae is the most common, followed by haemeophilus influenzae
HAP - pneumonia developed >48hrs after hospital admission.
Gram -ve enterobacteria or staph aureus most common
Aspiration - results from aspiration of oropharyngeal organisms.
More common in patients with stroke, myasthenia, low consciousness, oesophageal disease
What is the CURB 65 score?
A scoring system to help guide if hospital management of pneumonia is needed.
Confusion (AMTS 7 = 1 point) Respiratory rate (>30 = 1 point) BP (systolic 3 indicates severe disease inform ITU
Which pneumonia is most commonly complicated by influenza?
Staphylococcal
Causes bilateral cavitating bronchopneumonia
Where does Klebsiella pneumonia usually affect?
The upper lobes
Which pathogens cause atypical pneumonia, and what is atypical about them?
Mycoplasma pneumonia
occurs in epidemics every 4 years
has insidious onset with flu like symptoms followed by dry cough
CXR usually looks worse than the symptoms suggest Autoimmune haemolytic anaemia may occur as a result of cold agglutinins
Associated with skin rashes
Legionella pneumophilia
Colonizes water tanks and air conditioning units
Flu like symptoms preceed a dry cough and SOB.
Extra pulmonary features - anorexia, D+V, hepatitis, renal failure, confusion
CXR - bibasal consolidation
Lymphopenia, hyponatraemia
Urine - haematuria,
Chlamydophila pneumoniae
Biphasic illness: pharyngitis followed by pneumonia
Chlamydophila psittaci
Acquired from parrot
Headache, fever, ,dry cough, lethargy, arthralgia,
Extra pulmonary - menigoencephalitis, infective endocarditis, hepatitis, nephritis, rash, splenomegaly
Who gets PCP?
Patients are are immunocompromised
Now called pneumocystis jiroveci
Dry cough, exertional dyspnoea, fever. bilateral creps
What are the causes of PE?
Clot breaking off from a pre-existing venous thrombosis
RARE: Right ventricular thrombus (post MI) Septic emboli (right sided endocarditis) Fat, air or amniotic fluid embolism Neoplastic cell Parasites
What risk factors increase the chance of developing a PE?
Recent surgery - espc abdominal/ pelvic or ortho Thrombophilia Leg # Prolonged bed rest Malignancy Pregnancy, the pill, HRT Previous PE
What are the symptoms, signs and results seen in PE?
Acute breathlessness and chest pain
Haemoptysis
Dizziness and syncope
Pyrexia, cyanosis, tachypnoea, tachycardia, hypotension, raised JVP, pleural rub
Signs of a DVT
Low PaO2 and PaCO2
Normal CXR
ECG - sinus tachy with signs of right heart strain or SI, QIII TIII
-ve d-dimer rules out, a +ve one does NOT rule it in
How do you treat a PE
LMWH + warfarin until INR is stable for 3months if provoked
If unprovoked then longer than 3 months depending on risks
If cardiovascularly unstable may need to thrombolyse
What is the scoring system used to classify patients risk of developing a VTE?
Wells Score
for PE: Clinical signs of DVT Is PE the most likely diagnosis HR >100 Immbolisation for >3days or surgery in previous 4 weeks Haemoptysis Malignancy
for DVT: Paralysis or casting of leg Bed ridden for 3 days or surgery in previous 4 weeks Swelling of entire leg Calf swelling >3cm compared to other leg Greater pitting odeama in symptomatic leg Collateral non varicose veins Malignancy Other diagnosis more likely (-2 points)
