Resp Flashcards

(44 cards)

1
Q

types of pneumothorax

A

primary spontaneous

  • tall, thin males
  • no history of lung disease
  • family history, marfans, smoking

secondary spontaneous

  • due to underlying lung disease
  • most commonly COPD
  • also
  • > TB
  • > pneumocystis jerovecii
  • > cystic fibrosis

traumatic

  • penetrating or blunt chest trauma
  • iatrogenic

tension
-complication of any of above

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2
Q

tension pneumothorax

A
  • occurs when pleural pressure exceeds atmospheric during inspiration and expiration
  • forms one way valve
  • > air can enter pleural space with inspiration
  • > less can exit with expiration
  • increasing pressure compresses veins
  • > reduced venous return
  • > decreased CO and hypotension
  • compression of lung tissue
  • > resp failure
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3
Q

hx and exam pneumothorax

A

hx

  • dyspnoea
  • pleuritic chest pain
  • > usually ipsilateral
  • spontaneous often occurs at rest
  • > can recount it occuring
  • risk factors
  • tension
  • > distressed
  • > severe dyspnoea

exam

  • typical
  • > increased work of breathing
  • > decreased chest expansion
  • > ipsilateral hyperinflation with intercostal widening
  • > tracheal deviation to contralateral
  • > hyper-resonate to percussion
  • > decreased breath sounds ipsilateral
  • > subcut emphysema
  • tension
  • > cyanosis
  • > decreased GSC
  • > diaphoresis
  • > hypotension
  • > tachycardia
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4
Q

ddx pneumothorax

A

EMPTIED

  • embolus
  • musculoskeletal
  • pericarditis
  • tamponade (haemopericardium)
  • infarct
  • effusion (eg haemothorax)
  • dissection
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5
Q

investigations pneumothorax

A

ABG
-resp alkalosis
ECG

FBC
trops
d-dimer

CXR

  • visceral pleural line
  • simple
  • > no mediastinum shift
  • tension
  • > mediastinum and tracheal shift to contra
  • > flaying of ribs
  • > flattening diaphragm

consider

  • ultrasound
  • > in trauma
  • > absence of lung sliding
  • CT
  • > in occult
  • > more sensitive than CXR
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6
Q

PE investigations

A
ECG
-non specific changes (RV strain)
ABG
-hypoxia
-alkalosis, hypocapnea
D-dimer
Troponin 
-can be elevated (RV strain)
FBC
-leukocytosis
EUC
-contrast
ESR
LFTs
Coags
-INR and aPTT (anti-coagulation)
bHCG
-pregnant female (thrombolysis)
CXR
-hamptoms hump
-westermarks sign
CTPA
V/Q scan
Compression U/S leg (proximal/whole)
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7
Q

PE investigation pathway

A

Pretest probability

  • Well’s PE
  • Geneva

Score interpretation

  • low=<2
  • intermediate=2-6
  • high=>6

PERC rule
-8 criteria to identify patients with low probability of PE where risk of testing outweighs risk of PE

Low

  • fulfil 8 PERC criteria = no testing needed
  • doesn’t fulfil all 8 = D-Dimer
  • D-Dimer >500ng/mL = CTPA
  • D-Dimer <500ng/mL = no further testing needed

Intermediate

  • D-Dimer <500ng/mL = no testing (unless frail)
  • D-Dimer >500ng/mL = CTPA

High

  • negative D-dimer cannot rule out (5% risk)
  • CTPA
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8
Q

indications for intubation

A

Airway patency?

  • decreased level of conscious –> loss of protective resp reflexes
  • PEF

Oxygenation/ventilation (respiratory failure)

  • worsening hypoxia/hypercapnea
  • RR>40

Clinical

  • work of breathing
  • exhaustion
  • cyanosis

Expectation of need for intubation

  • senior clinician expects deterioration
  • need for transport out of ED

Non responsive to NIPPV

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9
Q

investigations acute asthma

A
Pulse oximetry
ABG
PEF
-normal = >80%
-severe = <60%
ECG
FBC
EUC
LFTs
Trops
NT- BNP/BNP
D-Dimer 

CXR

Consider

  • CT chest (foreign body if non-opaque)
  • tryptase (anaphylasis)
  • spirometry (once stable)
  • > safety to discharge (%FEV1)
  • > useful in follow up
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10
Q

ddx asthma

A

Immediately Page FACEM

  • infection (pneumonia)
  • pneumothorax
  • foreign body
  • Anaphylaxis
  • COPD exacerbation
  • Embolism
  • MI (APO)
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11
Q

asthma pathophys

A

Most commonly IgE mediated hypersensitivity

Airway inflammation

  • mast cell activation central
  • > sensitisation to allergen
  • > degranulation of pulmonary mast cells with further exposure
  • early phase
  • > release of preformed mediators (eg. histamine)
  • > production of eicosanoids (eg. PGD2, cysteinyl LTs)
  • > direct stimulation of airway smooth muscle
  • > mucous production
  • > stimulation of neural reflex pathways (release of ACh)
  • late phase
  • > influx of inflammatory cells (basophils, eosinophils neutrophils, T helper cells)
  • > release of cytokines activates smooth muscle
  • > bronchoconstriction

Airway obstruction

  • can be regional or global
  • large and small airways involved
  • initially obstruction -> air trapping and hyperinflation
  • > predominately due to bronchoconstriction
  • > oedema and thickening of airway wall
  • > airway plugging with mucous and cellular debris

Airway remodelling

  • irreversible structural change superimposed on effects of inflammation and bronchoconstriction
  • histopath
  • > loss of normal pseudostratified epithelium
  • > increase in goblet cells
  • > fibrosis and thickening of reticular layer of basement membrane
  • > increased myofibroblasts
  • > increased vascularity
  • > increased smooth muscle mass and ECM

Bronchial hyper-responsiveness

  • decrease in FEV1 20% with challenge (eg. histamine)
  • alteration in smooth muscle function/mass
  • enhanced sensitivity of neural pathways
  • remodelling and structural abnormalities (eg. loss of airway parenchymal interdependence)
  • > tethering forces maintaining patency

Additional histo

  • Curschmann spirals
  • > spiral of mucous plugs from subepithelial glands
  • Charcot leyden crystals
  • > eosinophilic binding protein in sputum
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12
Q

Pathophys pneumonia

A

Gain access to lower respiratory tract

  • aspiration from oropharynx most common
  • > microaspiration normal, particularly in elderly
  • > increased risk with decreased LOC
  • > intubation
  • > dysphagia/motility disorders
  • haematogenous spread
  • > eg. tricuspid IE
  • local spread
  • > pleural or mediastinum

Overcome mechanical factors

  • gag and cough reflex
  • > bypassed with intubation
  • > decreased LOC
  • > neuromusculuar dysfunction (eg. stroke)
  • hairs and turbinates of nares
  • > sufficiently small particles
  • mucociliary elevator
  • > impaired in chronic lung disease (eg. COPD/CF)
  • > mucous thinned by influenza
  • > chlamydia pneumoniae produce ciliostatic factor
  • > mycoplasma pneumoniae shears off cilia
  • normal flora crowds out potential pathogens
  • > overwhelming inoculum
  • > overgrowth of commensals

Evade innate immune system
-alveolar macrophage phagocytosis, destruction, mucociliary elevator or lympthatics
->overwhelming inoculum
->virulence factors (eg. mycobacterium resistant to phagocytes)
-IgA opsonisation
->Strep pneumoniae produce protease that splits IgA
Neutrophil response
-immunocompromise
->diabetes, HIV
-drugs
->anti TNF alpha

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13
Q

path pneumonia

A

Pathology
Increased alveolar capillary permeability
-initially oedema (proteinaceous exudate)
->red hepatization (extravasation of RBCs and neutrophils)
->grey hepatization (neutrophils and fibrin deposition with bacterial clearance)
-resolution
->clearance of cell debris and fibrin by macrophage

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14
Q

ddx pneumonia

A

BE ACCTIVE

  • Bronchiectasis exacerbation
  • Exacerbation COPD/Asthma
  • Aspiration/foreign body
  • Cancer/mets
  • CCF
  • TB
  • ILD
  • Viral (bronchitis/influenza)
  • Empyaema (eg. IE)
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15
Q

CXR pneumonia types

A

Lobar

  • > most common strep pneumoniae
  • > consolidation of alveolar spaces
  • > homogenous opacification of lobe
  • > sparing of bronchi -> air bronchogram

Bronchopneumonia (lobular)

  • > associated with staph aureus
  • > direct inhalation and colonisation of bronchi
  • > patchy nodular or reticularnodular
  • > asymetrical and bilateral
  • > often lung bases
  • > does not cross fissures

Atypical

  • atypical bacteria, viruses and fungi
  • inflammation confined to interstitium and interlobular septa
  • patchy reticular pattern
  • often involves hilum
  • lack of consolidation

Round

  • seen only in paediatric
  • > lack of pores of Kohn
  • rounded opacities

Cavitating

  • complication of pneumonia
  • radiolucency superimposed on consolidation

Hemorrhagic

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16
Q

ddx PE

A

EMPPATHIIC

  • exacerbation of COPD/asthma
  • musculoskeletal
  • pneumothorax
  • pericarditis
  • aortic dissection
  • tamponade
  • HTN (pulmonary - chronic emboli)
  • infarct (MI)
  • infection (pneumonia/bronchitis)
  • CCF

DDx for DVT (BITCH Leg)

  • bakers cyst (ruptured)
  • injury (eg. tear)
  • tumour (leading to venous congestion)
  • cellulitis
  • haematoma
  • lymphagitis
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17
Q

investigations pneumonia

A

ABG

FBC
EUC
-risk score
LFT
-liver failure = poor prognosis
ESR
-monitor treatment
-non specific but high levels supports infection
Procalcitonin 
-non specific
-higher levels correlate with bacterial infection
Microbiology:
-treatment is usually successful with empiric
-diagnosis of causative agent rare
-indicated here due to severity/treatment resistance
Blood cultures
-positive for causative oragnism
Sputum culture and gram stain
-prior to antibiotics
PCR 
->faster than bacterial culture
->improves sensitivity/specificity
->can provide information on resistance 
->predominately for rapid identification of viral infection

CXR
-PA and lateral

Consider
-bronchoscopy
->bronchoalverolar lavage = 10^4 CFU/mL
->protected specimen brushing = 10^3CFU/mL
-urinary antigen
->once diagnosis has been made, if it can change therapy
->legionella
->strep pneumoniae
Serology for atypicals
->IgM for mycoplasma
->acute and convalescent phase (change in IgG status) for mycoplasma, chlamydophila, coxiella

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18
Q

severity score pneumonia

A

Severity

  • most sensitive is SMARTCOP
  • > indicates mortality risk
  • > predicts need for intensive respiratory support and pressor support
  • > requires invasive testing and many investigations (eg. CXR)
  • CORB
  • > predicts need for intensive respiratory support and pressor support
  • > Confusion (acute onset)
  • > O2 <90%
  • > RR >30
  • > Blood pressure (SBP <90, DBP <60)
  • > score of 2 or more = high risk and need for ICU
19
Q

Admission score pnuemonia

A

CURB 65

  • > recommended by british thoracic society and eTG
  • > Confusion (acute onset)
  • > Uraemia
  • > RR >30
  • > BP (SBP <90, DBP <60)
  • > Age >65
  • scores
  • > 0-1 = 30 day mortality <3% (outpatient)
  • > 2 = 30 day mortality 9% (inpatient)
  • 3-5 = 30 day mortality 15-40% (consider ICU)

Also CRB65
PSI no longer used

20
Q

pneumonia complications

A

SARACEN

  • Sepsis/septic shock
  • ARDS
  • Rash (haemophilus: maculopapular, SJS)
  • Abscess/empyema
  • Cardiac (CCF, MI, arrhythmias)
  • Effusion
  • Necrotising
21
Q

pathogenesis COPD

A

Oxidative stress

  • in a genetically susceptible individual
  • chronic smoke exposure
  • > great than 10-15 pack year

Protease/antiprotease

  • oxidants activate macrophages and epithelial cells
  • > release of cytokines and influx of inflamm cells (neutrophils)
  • > imbalance of protease/antiprotease
  • > elastase from neutrophils, MMP from macrophages
  • > degradation products of both activate each other
  • > destruction of elastic fibres and ECM

Oxidant/antioxidant

  • deactivation of histone deacytelases
  • > transcription of proinflammatory genes
  • recruitment and activation of CD8 T cells and neutrophils
  • > imbalance in oxidant/antioxidant pathways
  • > drives inflammation and immune cell activation

Apoptosis and ineffective repair

  • chronic inflammation continues long after smoking cessation
  • drives apoptosis
  • impaired phagocytosis of cellular debris
  • > inadequate release of growth factors
  • septation and alveologenesis does not appear possible in adult lung
22
Q

pathology COPD

A

Large airways

  • chronic inflammation
  • > predominantly lymphocytes, macrophages, neutrophils
  • > hyeraemia and oedema of mucosa
  • hyperplasia and hypertophy of mucous glands
  • > trachea, bronchi and bronchioles
  • > hypersecretion and mucopurelent sputum
  • squamous cell metaplasia
  • > carinogenesis
  • > impaired mucociliary apparatus
  • smooth muscle hypertrophy

Small airways

  • Replacement of Clara cells by goblet cells
  • > increase mucous secretion and plugging
  • > increased surface tension and narrowing
  • further obstruction
  • > oedema
  • > inflammatory infiltrate
  • > fibrosis
  • airflow obstruction
  • > progresses to hyperinflation

Parenchyma (Emphysema)

  • perforation and obliteration of gas exchanging spaces
  • > coalesce into enlarged airspaces distal to terminal bronchioles
  • > respiratory bronchioles, alveolar ducts, alveoli
  • different types
  • > centrilobular most common, seen in smokers = resp bronchiole
  • > panlobular, alpha 1 antitrypsin = everything distal to resp bronchiole
  • > distal-lobular = pneumothorax

Vasculature

  • chronic hypoxia
  • > intimal hyperplasia
  • > smooth muscle hypertrophy/plasia
  • emphysema
  • > loss of capillary bed
  • all leads to HTN
23
Q

ddx COPD

A

BATCHED

  • Bronchiectasis
  • Asthma
  • TB
  • Constrictive bronchiolitis
  • Heart failure
  • Esophageal reflux
  • Drugs (eg. ACEI)
24
Q

investigations COPD

A
ABG
-respiratory failure
->type 1 = PaO2 <60
->type 2 = hypoxia with PaCO2 >50
-resp acidosis 
-HCO3 compensation to chronic resp acidosis
->increase 4 mmol/L for every 10mmHg increase in CO2
ECG
FBC
-anaemia
-WCC
EUC
-electrolytes
-acidosis
BNP
TSH
Glucose
-lethargy

CXR

  • ddxs
  • hyperinflation
  • > 6 anterior ribs mid clavicular line
  • flattened diaphragm
  • increased retrosternal airspace
  • attentuation of vascular markings
  • bullae
  • pulmonary HTN
  • > pulmonary artery prominent
  • > hilar vascular shadows
  • > cardiothoracic ration >0.5

Spirometry

  • pre and post bronchodilator
  • > obstruction (GOLD criteria) = FEV1/FVC <0.7 post
  • no reducibility in COPD

Consider:

  • sputum culture/stain
  • flow/volume loops
  • DLCO
  • > emphysema
  • body plesthismography
  • > hyperinflation vs restriction
  • alpha 1 anti trypsin
  • > if family hx
25
lights criteria
if anyone one of following is present = exudate - pleural/serum protein >0.5 - pleural/serum LDH >0.6 - pleural LDH >2/3 upper limit normal
26
pleural effusion ddx
exudative (PAINTERS) - pneumonia - abscess - infarct - neoplasia - TB - empyema - rheumatoid pleurisy - SLE/sarcoid/scleroderma transudative (CHARM - CCF/cirrhosis - hypothyroidism - albumin - renal failure - mets to draining nodes
27
pleural effusion investigations
Urinalysis Glucose ECG ABG ``` FBC EUCs -kidney failure LFTs -cirrhosis CMP Albumin Serum protein CRP LDH BNP/NT BNP ``` CXR ->ultrasound if positive to localise fluid Thoracocentesis -pleural fluid analysis Consider - chest CT - >malignancy and TB - culture/gram stain (if signs of infection) - >blood - >sputum - >pleural fluid
28
hx and exam PE
DVT -wells criteria PE Hx - dyspnoea (and orthopoea) - pleuritic chest pain - cough - wheezing - haemoptysis - calf pain - palpitations - syncope PE exam - tachypnea - tachycardia - obstructive shock - rales - wheeze - soft breath sounds - prominent P2 - elevated JVP - tender, erythematous, swollen calf
29
post acute care asthma
Don't discharge until - Spiro FEV1 >60% predicted - SABA <4 hrly Hx: - consider patient context (eg. help at home/time of day) - psych factors - risk factors for life threatening (eg. previous ICU) If discharged: - >continue oral prednisone 5-10 days - >start/continue ICS - >review inhaler technique - >assess adherence to drug regime - >identify triggers, discuss avoidance - >formulate and discuss asthma action plan - >GP within 2 days - >consider specialist review
30
spiro asthma
FEV1/FVC normal range - 0.85 for teenager - minus 0.05 every decade after FEV1 improvement - after 4 puffs salbutamol - after 15 mins - increase 12% or 200mL
31
asthma control and risk assessment
Risk - asthma flare ups within 12 months - no action plan - ED/ICU visits Good Control: - daytime symptoms <2 per week - use SABA <2 per week - no limitation on ADLs - no night symptoms Poor Control: -absence of above criteria
32
asthma triggers
PADDIES - Pollen - Animal dander - Drugs (aspirin, beta blockers) - Dust/dust mites - Infection (viral URTI) - Exercise - Smoking/smoke/air pollution
33
monitoring asthma
Timing - following flare ups and hospital admissions - 6 monthly - opportunistically for non-asthma appointment Assess - symptom control - >Primary care Asthma Control Screening tool - >frequency reliever medication - >spirometry annually - treatment issues - >inhaler technique (6 monthly) - >adherence - >understanding/review of asthma action plan (annually) - >comorbidities
34
ddx caveatting lesion on CXR
CASINO - Cyst/bullae - Autoimmune/vasculitis (granulomatosis with polyangitis) - Septic emboli - Infarct - Neoplasia - Organising pneumonia
35
hx and exam COPD
``` HPC -chronic cough -sputum production ->usually mucoid, purulent during exacerbation ->less than bronchiectasis -dyspnoea ->initially exertional then at rest -wheezing -chest tightness -weight gain or loss -lethargy -ddx ->fever, night sweats, infective symptoms ->coryzal symptoms = post nasal drips ->atopy = asthma PMH -exacerbations -asthma -GORD -comorbid ->lung cancer ->bronchiectasis ->CCF ->anxiety and depression FHx -COPD -alpha 1 anti trypsin -lung cancer Meds -ACEI Social .-impact on ADLs -pack year history -occupational exposure ->dust, smoke etc -travel ->TB ``` Exam - appearance - >can be cyanotic - >cachexic - increased work of breathing - >accessory muscles - >tripod - >pursed lips - barrel chest - diaphragm - >harrisons sulcus - >hoovers sign - hands - >nicotine staining - >asterixis - auscultation - >wheeze - >crepitations - >reduced air entry - percussion = hyper-resonate - heart - >elevated JVP - >distant heart sounds - >hepatomegaly - >kussmauls sign
36
spiro measures
FEV1: - most important for monitoring progress/severity - normal - >4L man - >3L women - abnormal - >best if lower 5th percentile - >below 80% predicted - COPD - >normal less than 1-1.5L FEV1/FVC - most important for identifying obstruction - abnormal - >best is lower 5th percentile - >less than 0.7
37
flow loops
Graph - flow on Y axis, volume on X - FEF50/FIF50 - >flow at mid vital capacity for insp/exp - >normal = <1 - variable intrathoracic obstruction - >FEF/FIF reduced - >normal inspiratory curve - >flattened exp - variable extrathoracic - >FEF/FIF increased - >normal expiratory curve - >flattened inspiratory - lower airway obstruction (COPD) - >scooped out expiratory curve - >loss of elastic recoil/compliance during effort-independent phase - restrictive (ILD) - >sharp rise and fall in expiratory (increased elasticity) - >decreased vital capacity - abnormal inspiratory and expiratory - >normal FEF/FIF - >tracheal stenosis - >severe COPD
38
pleural effusion pathophys
INCREASED FLUID ENTRY increased permeability (exudative) - eg. tumour - >local release of cytokines such VEGF - >mast cell release of tryptase - as protein content is not altered by fluid absorption - >high protein content increased pressure (transudative) - increase sieving of proteins - >low protein content in fluid - usually due to elevation in venous pressure - >systemic for parietal pleura - >pulmonary for visceral pleura - cardiogenic - >increase pulmonary venous pressure - >increase in bronchial capillary pressure - >interstitial oedema (interlobular septae and peribronchovascular space) - >filter across visceral pleura decrease pleural pressure - seen in atelectasis - decreases extravascular hydrostatic force decrease plasma oncotic pressure -hypoalbuminaemia DECREASED FLUID EXIT lymph exit dependent on... decreased lymph contractility - hypothyroidism - exotoxins resp motions -paraylsis patency -pleural fibrosis or malignancy lymphatic or venous verus pleural pressure - decrease in pleural pressure with atelectasis - increase in systemic venous - >eg superior vena cava syndrome - increase in lymphatic - >eg. malignancy of draining lymphatics
39
pleural fluid analysis
gross observation - pale straw coloured = transudate - blood = malignancy or trauma - milky = chylothorax lights - protein - LDH transudate - BNP/NT BNP in pleural fluid - LFTs - EUCs/urinalysis exudate - cholesterol - >high in exudative - triglycerides - >high in chylothorax - glucose - >low in infection/neoplasia/rheumatoid - pH - >low in infection - cell count and differential - >lymphocytes = ?TB - >eosinophilia = low in malignancy - adenosine deaminase - >TB
40
whooping cough pathophys
aetiology - bordetella pertussis - >also other bordetella species pathophys - spread by aerosol droplets - >highly infectious - >80% of susceptible household contacts with develop clinical disease after sick contact - adhesins - >binding to resp epithelium of upper tract and nasopharynx - tracheal cytotoxin - >local tissue damage - >micro aspiration and cough - pertussis toxin - >lymphocytosis - eventually colonisation - >alveolar macrophages - >ciliated resp epithelium - adenylate cyclase - >evades phagocytosis and immune destruction - >chronic cough
41
whooping cough clinical stages
stage 1: catarrhal - URTI symptoms - 1-2 weeks stage 2: paroxysmal - usually last 6 weeks - cough - >becomes progressively worse then improves within this time - typical symptoms - >post tussive emesis - >inspiratory whoop stage 3: convalescent - 2-3 weeks - cough - >declining in frequency - exacerbations - >common with URTI for many months after
42
investigations whooping cough
SpO2/ABG - >apnea - >hypoxic encephalopathy FBC -lymphocytosis EUC -electrolytes with vom nasopharyngeal - swab - >culture - >fastideous - >neg culture does not rule out diagnosis - aspirate - >PCR - >high sensitivity and specificity consider - serology - >IgA/IgG - >only indicates previous infection or immunisation - CXR - >pneumonia is complication - >atelectasis, perihilar infiltrates
43
ddx whooping cough
Uncontrolled Apnea GASP - URTI - >viral - Aspiration foreign body - GORD - Asthma - Sinusitis - >allergic - >post nasal drip - Pneumonia - >CAP
44
ddx haemoptysis
CHAIN - cardiovascular - >LV failure with mitral stenosis - >AVM - haematological - >coagulopathy - autoimmune - >rheumatoid pleurisy - >wegeners - infectious - >bronchitis (most common) - >bronchiectasis - >pneumonia - >TB - neoplasia - >primary (mainly SCLC) - >mets (skin, breast, colon, renal) - >lymphoma