Respiratory Flashcards
3 key features of asthma?
- airflow limitation which is reversible
- airway hyper-responsiveness to a wide range of stimuli
- inflammation of the bronchi
symptoms of asthma
cough often worse at night
dyspnoea
wheeze
chest tightness
signs on spirometry of asthma
FEV1 significantly reduced
FVC normal
therefore FEV1/FVC <70%
shows bronchoconstriction
Mx of asthma
SABA e.g. salbutamol
SABA + ICS e.g. budenoside 400mcg OD or beclomethasone
SABA + ICS + LTRA (leukotriene receptor antagonist) e.g. Montelukast
SABA + ICS + LABA e.g. salmeterol (can continue LTRA)
SABA +/- LTRA + MART (maintenance and reliever therapy- contains low dose ICS and LABA)
Trial of long-acting muscarinic antagonist or theophylline
increase ICS
SEs of ICS?
oral candidiasis and stunted growth in children
when should children with asthma be given a paediatric ICS?
Not controlled with SABA
OR
Newly-diagnosed asthma with symptoms >= 3 / week or night-time waking
what are the steps after SABA + pICS for childhood asthma?
- add leukotriene receptor antagonist
- then stop LTRA and add LABA (different to adult guidance)
- SABA + MART
What is MART
a form of combined ICS and LABA
used for both daily maintenance therapy and the relief of symptoms as required
signs of life-threatening of acute asthma?
PEFR <33% O2 sats <92% Silent chest, cyanosis or feeble respiratory effort bradycardia, dysrhythmia, hypotension exhaustion, confusion, coma
signs of severe acute asthma?
PEFR 33-50%
Can’t complete sentences
RR >25/min
Pulse >110 bpm
mx of acute severe asthma?
salbutamol nebs prednisolone or IV hydrocortisone magnesium sulphate 1.2-2g IV over 20 mins IV aminophylline IV salbutamol
causes of COPD?
Smoking
alpha-1 antitrypsin deficiency
causes of IECOPD?
H.influenza
Strep pneumoniae
Moraxella catarrhalis
features of COPD?
Cough: often production
dyspnoea
wheeze
Right heart failure
Ix of COPD?
airflow obstruction- FEV1/FVC ratio <70%
CXR
FBC-exclude polycythaemia
FEV1 severity of COPD?
>80%= stage 1- mild 50-79%= stage 2- moderate 30-49%= stage 3- severe <30%= stage 4- very severe
general management of COPD?
stop smoking
annual influenza vaccination
one-off pneumococcal vaccine
pulmonary rehab
drug management of COPD
- SABA or SAMA is first line
- if not steroid responsiveness- LAMA (tiotropium)+ LABA
- if steroid responsiveness- LABA (salmeterol) + ICS (beclomethasone 200mcg BD)
- Consider adding theophylline
others- azithromycin (oral prophylactic antibiotic therapy), mucolytics
who shouldn’t you offer LTOT for COPD?
If people continue to smoke
who should get LTOT?
Long-term O2 therapy- >15 hours a day. Used in patients with pO2 <7.3kPa or 7.3-8kPa and one of:
- very severe airflow obstruction (FEV1 <30%)
- cyanosis
- polycythaemia
- peripheral oedema
- raised JVP
- O2 sats <92%
What is a well’s score?
Shows likelihood of DVT
Active cancer (treatment ongoing, within 6 months, or palliative)
- Paralysis, paresis or recent plaster immobilisation of the lower extremities
- Recently bedridden for 3 days or more or major surgery within 12 weeks requiring general or regional anaesthesia
- Localised tenderness along the distribution of the deep venous system
- Entire leg swollen
- Calf swelling at least 3 cm larger than asymptomatic side
- Pitting oedema confined to the symptomatic leg
- Collateral superficial veins (non-varicose)
- Previously documented DVT (-2)
> 2= DVT likely
1 or less= unlikely
An alternative diagnosis is at least as likely as DVT
what to do if DVT is likely?
proximal leg vein USS
if negative-> D-dimer
what to do if DVT unlikely?
D-dimer
if positive -> arrange USS asap
if can’t do USS in 4 hours -> LMWH
Mx of DVT?
LMWH or fondaparinux- continued until INR >2 for at least 24 hours
Give a vitamin K antagonist i.e. warfarin for 3 months
At 3 months clinicians should assess the risks and benefits of extending treatment.
If unprovoked DVT- full physical examination, CXR, bloods (FBC, serum calcium, LFTs) and urinalysis
what needs doing in patients over 40 with first unprovoked DVT/PE?
investigate for malignancy with abdo-pelvic CT scan
features of PE?
Chest pain (pleuritic) dyspnoea haemoptysis tachycardia tachypnoea
mx of PE?
Same as DVT
thrombolysis if massive PE where there is circulatory behaviour
IVC filters if repeat PE
causes of upper zone fibrosis
CHARTS Coal worker's pneumoconiosis Hypersensitivity pneumonitis Ankylosing spondylitis Radiation TB Silicosis/sarcoidosis
diagnosis of lung fibrosis
restrictive picture: FEV1 normal/decreased, FVC decreased, FEV1/FVC increased
CXR- ground-glass appearance, progresses to opacities
CT-diagnostic
what is coal-workers’ pneumoconiosis?
caused by long term exposure to coal dust particles, can be a long lead time 1st exposure and development of disease
caused by accumulation of macrophages in the alveoli which starts an immune response, causing damage to the lung tissue
what can coal-workers’ pneumoconiosis lead to?
Simple pneumoconiosis- opacities in lungs, can be asymptomatic
Progressive massive fibrosis- dust exposure causes patients to develop round fibrotic masses which can be several cms. Symptomatic with SOB, cough, black sputum
What are the effects of asbestos on the lung?
- pleural plaques
- pleural thickening
- asbestosis- lower lobe fibrosis
- mesothelioma- malignant disease of the pleura
- lung cancer
which type of lung cancer has the worst prognosis?
SCLC
What are the main types of non small cell LC?
squamous (35%)
adenocarcinoma (30%)
large cell (10%)
features of SCLC?
Arises from APUD cells
Associated with ectopic ADH, ACTH secretion
ADH-> hyponatraemia
ACTH -> cushing’s syndrome, bilateral adrenal hyperplasia
Lambert-Eaton syndrome: antibodies to voltage gated calcium channels causing myasthenic like syndrome
mx of SCLC?
usually mets at time of diagnosis
surgery
chemoradiotherapy
features of NSCLC?
SCC-
typically central, associated with PTHrP secretion -> hypercalcaemia + finger clubbing
HPOA- hypertrophic pulmonary osteoarthropathy
Adenocarcinoma-
typically peripheral
most common type in non-smokers, can cause HPOA and gynaecomastia
large cell- typically peripheral, poorly differentiated tumours with a poor prognosis, may secrete bHCG
mx of NSCLC?
Only 20% suitable for surgery
curative or palliative radiotherapy
2 week wait criteria for lung cancer
CXR features that suggest lung cancer over 40 with unexplained haemoptysis over 40 with 2 of the following: - cough - fatigue - SOB -chest pain - weight loss - appetite loss
Consider if over 40 and persistent chest infections, clubbing, supraclavicular lymphadenopathy, thrombocytosis
what is bronchiectasis?
a permanent dilatation of the airways secondary to chronic infection or inflammation
causes of bronchiectasis?
post-infective- TB, measles, pertussis, pneumonia
CF
Bronchial obstruction
Immune deficiency- selective IgA, hypogammaglobulinaemia
ABPA
What is a transudate and exudate?
transudate= <30g/L of protein exudate= >30g/L of protein
causes of transudate pleural effusion?
heart failure
hypoalbuminaemia (liver disease, nephrotic syndrome, malabsorption)
Meig’s syndrome
causes or exudate pleural effusion?
Infection e.g. pneumonia. TB subphrenic abscess connective tissue disease- RA, SLE neoplastic pancreatitis PE Dressler's syndrome yellow nail syndrome
features of pleural effusion?
dyspnoea
non-productive cough or chest pain
Ix of pleural effusion?
CXR
Pleural aspiration- USS guided
contrast CT
How to distinguish between transudate and exudate pleural effusion?
Light’s criteria if the protein level is between 25-35g/L
an exudate is likely if at least one of the following criteria are met:
- pleural fluid protein/ serum protein >0.5
- pleural fluid LDH/ serum LDH >0.6
- pleural fluid LDH more than 2/3 the upper limits of normal serum LDH
what diagnosis is likely if pleural effusion has blood staining?
Mespthelioma
PE
TB
what diagnosis is likely if pleural effusion is purulent or turbid/cloudy?
infection (needs chest drain)
how to manage a recurring pleural effusion?
recurrent aspiration
pleurodesis
indwelling pleural catheter
opioids to relieve dyspnoea
what is sarcoidosis?
a multisystem disorder of unknown aetiology characterised by non-caseating granuloma
RFs of sarcoidosis?
young adults
African descent
features of sarcoidosis?
Acute- erythema nodosum, bilateral hilar lymphadenopathy, swinging fever, polyarthralgia
Insidious- dyspnoea, non-productive cough, malaise, weight loss
Skin- lupus pernio
Hypercalcaemia
Ix of sarcoidosis
clinical Dx ACE levels- 60% sensitive and 70% specific high calcium, high ESR CXR Spirometry- restrictive defect tissue biopsy- non-caseating granuloma
mx of sarcoidosis?
steroids if CXR stage 2 or 3, hypercalcaemia, eye, heart or neuro involvement
common organisms for aspiration pneumonia?
Streptococcus pneumoniae
staph aureus
H. influenzae
pseudomonas aeruginosa
Common organisms causing pneumonia?
Streptococcus pneumoniae
H.influenzae (esp if COPD)
Staph aureus
Mycoplasma pneumoniae- atypical pneumonia- presents as dry cough and atypical chest signs/CXR
Legionella pneumophilia- secondary to air conditioning units. Hyponatraemia and lymphopenia common
Klebsiella pneumoniae
PCP- HIV patients
how does PCP present
HIV patients
dry cough, exercise-induced desaturations and the absence of chest signs
S+S of pneumonia?
cough, sputum, dyspnoea, chest pain, fever
reduced breath sounds, bronchial breathing
reduced O2 sats
Ix for pneumonia?
CXR Bloods- FBC, U&Es, CRP ABG Blood and sputum cultures Pneumococcal and legionella urinary antigen tests
how are patients assessed for pneumonia?
CURB65 Confusion (AMT <8) Urea (>7mmol/L) Resp rate >30/min Blood pressure: SBP <90 or DBP <60 65 years plus
0- manage in community
1- SaO2 assessed which should be >92% to be safely managed in the community and CXR performed
2- manage in hospital
mx of low severity CAP?
Amoxicillin- 5 days
if allergic macrolide or tetracycline
mx of moderate and high severity CAP?
Dual abx therapy with amoxicillin and a macrolide -7-10 day course
if high severity- use co-amoxiclav instead
what is FEV1?
volume of air exhaled in 1 second
what is FVC?
Maximum volume of air a person can exhale
What spirometry readings does thoracic kyphosis produce?
restrictive disease
means air can leave the lungs quickly but due to poor lung expansion FVC is low so ratio is higher
what is TLCO?
Total gas transfer
an overall measure of gas transfer for the lungs from the alveoli into the capillaries and reflects how much O2 is taken up into the red cells
what medications are given to help smoking cessation?
nicotine replacement therapy
varenicline- nicotine receptor partial agonist (start 1 week before stop date)
bupropion- NA and DA reuptake inhibitors
target stop date needed
SEs of NRT?
n&v, headaches, flu-like symptoms
SEs of varenicline?
nausea, headaches, insomnia, abnormal dreams
CI- pregnancy and breast feeding
SEs of bupropion?
risk of seizures
CI- epilepsy, pregnancy and breast feeding
S&S of pneumothorax?
dyspnoea chest pain: often pleuritic sweating tachypnoea tachycardia
what is a tension pneumothorax?
lung parenchymal flap is formed following trauma
trachea shift and hyper-resonance on affected side
tx of tension pneumothorax?
needle decompression and chest tube
mx of pneumothorax?
if the rim of air is <2cm and the patient is not SOB -> discharge
otherwise, aspiration
chest drain if not successful
RFs for pneumothorax?
pre-existing lung disease
connective tissue disease- marfan’s, RA
ventilation
catamenial pneumothorax (spontaneous in menstruating women)
what meds to give in hospital acquired pneumonia of <5 days?
co-amoxiclav or cefuroxime
what meds to give in hospital acquired pneumonia of >5 days?
piperacillin with tazobactam or broad spec cephalosporin e.g. ceftazidime
what is ARDS?
Acute respiratory distress syndrome (ARDS) is caused by the increased permeability of alveolar capillaries leading to fluid accumulation in the alveoli, i.e. non-cardiogenic pulmonary oedema
causes of ARDS?
infection: sepsis, pneumonia massive blood transfusion trauma smoke inhalation acute pancreatitis cardio-pulmonary bypass
features of ARDS?
dyspnoea
elevated respiratory rate
bilateral lung crackles
low oxygen saturations
Ix of ARDS?
CXR
ABG
mx of ARDS?
due to the severity of the condition patients are generally managed in ITU
oxygenation/ventilation to treat the hypoxaemia
general organ support e.g. vasopressors as needed
treatment of the underlying cause e.g. antibiotics for sepsis
certain strategies such as prone positioning and muscle relaxation have been shown to improve outcome in ARDS
What are the key indications for non-invasive ventilation?
COPD with respiratory acidosis pH 7.25-7.35*
type II respiratory failure secondary to chest wall deformity, neuromuscular disease or obstructive sleep apnoea
cardiogenic pulmonary oedema unresponsive to CPAP
weaning from tracheal intubation
what is tidal volume?
volume inspired or expired with each breath at rest
500ml in males, 350ml in females
causes of respiratory acidosis?
COPD
decompensation in other respiratory conditions e.g. life-threatening asthma / pulmonary oedema
neuromuscular disease
obesity hypoventilation syndrome
sedative drugs: benzodiazepines, opiate overdose
causes of respiratory alkalosis?
anxiety leading to hyperventilation pulmonary embolism salicylate poisoning* CNS disorders: stroke, subarachnoid haemorrhage, encephalitis altitude pregnancy
criteria for steroid-responsiveness in COPD (asthmatic features)
prev diagnosis of asthma
higher blood eosinophil count
sustainable variation in FEV1 over time
substantial diurnal variation in peak expiratory flow (at least 20%)
what type of asbestos is the most serious form?
crocidolite (blue)
what is mesothelioma and symptoms?
malignant disease of the pleura
- progressive SOB
- chest pain
- pleural effusion
mx of mesothelioma?
palliative chemo
review areas in a CXR?
behind the heart
under diaphragm
apices
costophrenic angles
predisposing factors for pneumothorax?
COPD asthma pulmonary fibrosis cystic fibrosis trauma iatrogenic- central venous line obstruction, mechanical ventilation
description of pulmonary fibrosis on CXR?
diffuse reticulonodular shadowing
causes of upper lobe fibrosis?
BREAST Berylliosis Radiation fibrosis EAA AS Sarcoidosis TB
causes of lower lobe fibrosis?
connective tissue disease
asbestosis
cryptogenic fibrosing alveolitis
drug-induced- amiodarone, methotrexate
causes of unilateral pleural effusions?
malignant tumours parapneumonic PE infarction rheumatoid disease
3 most common causes of left lower lobe collapse (sail sign)
- central hilar or endobronchial mass
- endobronchial foreign body esp children
- endobronchial mucus plug e.g. asthma
Ix= bronchoscopy and CT thorax
scenario: acute on chronic SOB in a young person?
cystic fibrosis with new pneumothorax
what does pulmonary oedema look like on CXR?
bat wing sign
causes of pulmonary oedema with and without cardiomegaly?
with CM- HF
without CM- acute renal failure, ARDS, after aggressive fluid resuscitation, massive acute PE, SAH
differentials for a large globular heart and what to ask about in history?
congenital cardiac disease
cardiomyopathy
pericardial effusion
(ask about childhood illness and FH cardiac disease)
signs of mitral valve disease on CXR?
moderately enlarged heart
prominence of left atrial appendage
double RHB- enlargement of left atrium
causes of clubbing?
resp- pulmonary fibrosis, LC, abscess, bronchiectasis, CF
cardio- IE, cyanotic heart diseases
GI- IBD, coeliac, cirrhosis
thyroid- hyperthyroidism
causes of interstitial lung disease?
occupational- asbestosis, sarcoidosis, coal dust, birds, hay, fungus
meds- radiation, methotrexate, amiodarone, nitrofurantoin
idiopathic pulmonary fibrosis
connective tissue disease- RA, systemic sclerosis, AS, dermatomyositis/polymyositis
others but learn these main ones!
differential diagnosis of unilateral hilar enlargement vs bilateral hilar enlargement?
Unilateral: bronchial carcinoma TB lymphoma metastatic mediastinal lymph node disease
Bilateral: Sarcoidosis Lymphoma Pulmonary hypertension Metastatic nodal disease
differential for a cavitating lung lesion?
bronchial carcinoma TB cavitating pneumonia lung abscess rheumatoid nodule vasculitic disease e.g. Wegener's granulomatosis
signs of left upper lobe collapse on CXR?
volume loss of left hemithorax (lung) with veil sign (opacification over whole lung)
may have increased density indicating a mass around the left hilum
trachea and mediastinum may be deviated to the left
if there is lobe collapse, is the trachea deviated towards or away?
towards
If there is a ‘white-out’ of a hemithorax it is useful to assess the position of the trachea - what does central, pushed or pulled tell you?
- Towards- Pneumonectomy, complete lung collapse e.g. endobronchial intubation, Pulmonary hypoplasia
- Central- Consolidation, Pulmonary oedema (usually bilateral), Mesothelioma
- Away- Pleural effusion, Diaphragmatic hernia, Large thoracic mass
differentials for an anterior mediastinal mass?
trachea deviated away
thyroid enlargement, thymoma, teratoma, lymphoma
CT- guided biopsy
what cancer can causes cannon-ball mets in a CXR?
renal cell carcinoma
others inc testicular malignancy and choriocarcinoma
do CT chest, abdo, pelvis
if the R heart border is not visible, what lobe is affected?
right middle lobe
what follow up to do after a lobar pneumonia?
CXR 6 weeks after Abx treatment
could be an underlying carcinoma
