Respiratory Flashcards
Compare signs in upper airway infections
Croup- 3mo-5y, barking cough/stridor + coryza
EBV- teenager, malaise/fatigue, lymphadenopathy/HSM
Quinsy/paratonsillar abscess- teenager, trismus, hot potato voice, drooling
Epiglottitis- toxic, fever, drooling, stridor, unvaccinated
Bacterial tracheitis- toxic, fever, stridor
Retropharyngeal abscess- odynophagia/dysphagia, drooling, dysphonia, neck stiffness/torticollis
Indications for neuraminidase inhibitors in pneumonia
Inpatients with complicated disease thought to be related to influenza
Patients requiring ICU during influenza season
Child with suspected influenza at high risk of complications (congenital heart disease, respiratory disease, or immunosuppression)
Most common cause pneumonia <5yrs & >5yrs
<5yrs = viral most common (adeno, entero, RSV, parainfluenza etc), bacterial - ENT bugs- strep pneumo, moraxella, h.influenza, MSSA, s.pyogenes
>5yrs = strep. pneumo, mycoplasma/chlamydia (atypical)
Pathogenesis of round pneumonia
Inter-alveolar communication and collateral airways (pores of Kohn and canals of Lambert) develop as children age and allow air-drift between the parenchymal subsegments- infection walled between these spaces
Signs of empyema on pleural fluid tap
Empyema consistent with:
pH <7.0
Glucose <40 mg/DL
LDH >1000 IU
Protein level > 3.0 g/dL
Pleural fluid: serum protein ratio >0.5
Syndromes associated with laryngeal cleft
G syndrome: hypertelorism, hypospadias, stridor, and swallowing difficulties
Opitz-Frias syndrome: midline defects (as above)
Pallister-Hall syndrome
VACTER/VACTERL
CHARGE
Distinguish saccular laryngeal cyst from larygocoele
Saccular cyst distinguished from a laryngocele in that its lumen is isolated from the interior of the larynx and it contains mucous, not air
Stages of lung development
Embryonic (Wk 4 -5) lung buds from ventral foregut, lobar division
Pseudoglandular (5-17) Airway branching- vascular & conducting airways complete
Canalicular(16-25) - bronchioles/ ^ capillaries, alveolar Type 1&2 alveolar cells, air blood barrier
Saccular (24-40) Alveolar ducts, air sacs
True alveoli seen by 32 weeks gestation – recognizable by 36 weeks
Alveolar (32-36 week to 8 years)
Secondary septation occurs, marked increase of the number and size of capillaries and alveoli
Most development is postnatal - 85% of alveolarization occurs postnatally
15 million alveoli at birth (term) 🡪 300-600 million as an adult [exponentially increase until 2 years old
When do babies have true alveoli
True alveoli seen by 32 weeks gestation – recognizable by 36 weeks
Alveolar (32-36 week to 8 years)
Differences between CPAM/Sequestration
CPAM - dysplastic lung mixed w normal lung, blood supply from lungs, connected to bronchial tree
Sequestration- blood supply systemic, no connection to bronchial tree
Difference intrapulmonary vs extrapulmonary sequestration
Intrapulmonary 75-85%, lower lobe, no pleura
Extrapulmonary 15-25% boys, L) lung, 60% assoc w congenital defects- Diaphragmatic hernia
Colonic duplication
Vertebral anomalies
Pulmonary hypoplasia + CPAM
Scimitar syndrom
Compare Granulomatosis w Polyangiitis & Churg-Strauss Syndrome
Systemic disease leading to interstitial lung disease
GPA: 90% cANCA raised, pulm hemorrhage, rhinosinusitis- nasal discharge/septum degradation- skin, joint, conjunctivitis, peri/myocarditis can be rapidly progressive
Rx: long term immunosuppression, plasma exchange, rituximab
Churg-Strauss: pANCA raised, rhinitis/asthma, eosinophilia, multisystem vasculitis (kidneys, skin, heart)
Rx: steroids
Symptoms of sarcoidosis
> 8yrs
Idiopathic, multisystem inflammatory disorder
Skin rash, iridocyclitis, and arthritis- often without lung Dx
CXR shows changes despite no Sx 90%
Bloods: hypergamm, ACE elevated, high Ca, elevated CD4
Bx: non-caseating granulomas- predominant in upper lobes, ACE
Rx: 75% self resolve, if Stage 3 and above steroids +/- other immunosuppression
Symptoms of sarcoidosis
> 8yrs
Idiopathic, multisystem inflammatory disorder
Skin rash, iridocyclitis, and arthritis- often without lung Dx
CXR shows changes despite no Sx 90%
Bloods: hypergamm, ACE elevated, high Ca, elevated CD4
Bx: non-caseating granulomas- predominant in upper lobes, ACE
Rx: 75% self resolve, if Stage 3 and above steroids +/- other immunosuppression
Mx of chylothorax
50% resolve spontaneously
Enteral feeds
Medium chain triglycerides (MCTs) can be provided – absorbed directly into intestinal cells and transported directly to the liver via the portal vein – BYPASSING the thoracic duct
TPN if not improving 1-2wks
Consider pleuroperitoneal shunt
Composition chyle
TG in the form of chylomicrons
T lymphocytes
Electrolyte concentration similar to plasma
Immunoglobulins and fat soluble vitamins
Dx of this CXR?
CCAM
- Hamartomatous or dysplastic lung tissue mixed with normal lung
- Often unilateral
- Connected to pulmonary blood supply
Type 1 – macrocystic, single or several large cysts
Type 2 – microcystic, multiple small cysts
Type 3 – lesion is solid with bronchiole-like structures, poorest prognosis
Present with resp distress as neonate if large, recurrent infection in childhood if small
Dx of this CXR?
Eventration of diaphragm
- elevation, with paradoxical downwards motion in other diaphragm
-Assoc: congenital cardiac lesions, pulmonary sequestrations and chromosome trisomies
Dx of this CXR?
Congenital lobar emphysema
- Most commonly L) upper lung/upper lung fields
- Usually presents neonatal period with resp distress
- Airspace widening w mediastinal shift/contralateral atelectasis
Dx of this CXR?
CDH
- Bochaldek - most common, more L) sided, resp distress at birth/diagnosed antenatally
- Foramen of Morgani (2-6%)- anterolateral, R) sided, asymptomatic
Dx of this CXR?
Pneumomediastinum
- Spinnaker sail sign
- Elevated thymus
- Conservative Mx
Dx of this CXR?
Eosinophillic pneumonitis
- Bilateral infiltrates
- Acute: often in teenagers, idiopathic, BAL shows >25% Eosinophils, Rx: steroids
- Chronic: more common in adults
Dx of this CXR?
Churg-Strauss
- Rhinitis -> eosinophilia -> vasculitis
- Skin, heart & GI manifestations, elevated pANCA, eosinophils on BAL
- More insidious onset
Dx of this CXR?
Miliary TB
> 2 organs affected
Early complication of primary infection
Due to massive release of organisms
CXR- diffuse, bilateral, micronodular pattern
Dx of this CXR?
Primary TB
Adenopathy with small parenchymal foci
Signs/ symptoms infrequent, non-specific
TB screening principles
TST
- Preferred first line screening test in children <5 years (less reliable in those <6 months)
-Contraindicated if previous TB disease or previous large reaction to TST
Positive:
>=5 mm in children who have household contacts
>=10 mm in children with history of close contact or endemic area
>=15 mm in all other children
FN: active disease, immunocompromise, recent infection
FP: BCG vaccine 50% 9-12mo post
- All children with positive TST need CXR
TB diagnosis
CXR
AFB culture- Sputum x3 early morning samples (can take up to 6wks), GeneXpert: real time PCR, higher sensitive in smear +ve disease
Dx of this CXR?
Bronchiolitis obliterans/BOOP
Diagnosis on HRCT/Bx
Patchy consolidation with a predominantly subpleural and/or peribronchial distribution
Small, ill-defined peribronchial or peribronchiolar nodules
The reverse halo sign (atoll sign) is considered to be highly specific, although only seen in ~20% of patients with cop 5.
Dx of this CXR?
Follicular bronchiolitis
- Lymphoproliferative Dx
- Rx steroids
Dx of this CXR?
Sarcoidosis
>8yrs presentation
Skin, rash, eye involvement, resp Sx less common, however 90% have CXR findings
75% self resolve, steroid responsive
Dx of this CXR?
Hypersensitivity pneumonitis
- Range of triggers- interstitial/alveolar disease
- Recurrent pneumonia following exposure 4-6h (birds, farm, humidifiers, mould)
- Upper zone predominant
Dx of this CXR?
GPA
- 90% cANCA positive
- Rapid onset/progression
- Rhinosinusitis, dyspnoea, pulmonary hemorrhages
- Rx: steroids, plasma exchange, immunosuppressants, rituximab
Biggest risk for future asthma exacerbations?
One or more severe or life-threatening flare-ups in the past year
Increased risk of life-threatening asthma- what condition?
Confirmed food allergy
Diagnosis asthma/airway obstruction on spirometry
Airway obstruction defined as:
FEV1 <80% (predicted)
FEV1/FVC <75% (varies with age)
MMEF 25-75 <67% (predicted)
Bronchodilator reversibility = improvement of FEV1 of 12% in absolute values
Role of FENO in asthma
Fractional exhaled NO (FeNO)
Suggests eosinophilic inflammation and supportive diagnosis
Not done in routine practice
Higher NO may be suggestive
What asthma med associated with decreased duration of hospital stay?
Steroids 🡪
Cause of VQ mismatch in salbutamol therapy
Can open up areas of poorly perfused lung/diversion of BF to other areas- leads to transient worsening of VQ mismatch, occurs early in illness.
5-10 mins until recorrects, supplemental O2 for Rx
Concern w safety of LABA in children?
LABA also results in phosphorylation and internalisation of beta 2 receptor – results in increased mortality
When would you trial leukotriene receptor antagonist first (monteleukast)
Trialed first IF:
The child is unable to use inhaled therapy
The child also has significant allergic rhinitis
The parents have strong concerns about adverse effects of ICS
Role of omalizumab/mepolizumab in asthma & MOA
Omalizumab:
Humanised anti-IgE Mab
Prevents binding of free IgE to high affinity receptors on basophils and mast cells
Approved for moderate to severe allergic asthma in children 12 years or older
Mepolizumab:
An add-on maintenance therapy for severe asthma with an eosinophilic phenotype in patients age 12 years and older
Anti-IL-5 Mab injected SC every 4 weeks
CF infections:
Which bug is the…
- most common overall
- second most common in early life
- risk factor for reduced survival
- contraindication to transplant
+ ABx used to treat
Staph aureus most common overall (MRSA = worse survival)
- Fluclox/cefalexin/IV Vanc, amoxicillin prophylaxis if colonised <12mo
Haemophilus Influenzae - second most common in early life
- Augmentin
Burkholderia Cenocepacia- contraindication to transplant
- Ciprofloxacin/bactrim
Pseudomonas Aeruginosa - risk factor for reduced survival/pulmonary decline
- Tobramycin (neb)/oral cipro
Features of NMTB infection in CF
Form mycobacterium abscess complex, requires prolonged Rx- intensive IV tigecycline/cefoxitin/azithromycin, treat other potential infections
Features of ABPA in CF
- Usually >6yrs, 15% pts with CF, also seen in asthma
- Exaggerated Th2 response to aspergillus in bronchi
- Increasing SOB/cough/wheeze, orange/rust coloured mucous
- CXR: evidence of infiltrates especially in UL + centrally/ ‘gloved finger’ appearence/tree-in-bud
- Ix: high total IgE, eosinophilia, IgG +ve for aspergillus
Rx: high dose steroids, itraconazole, omalizumab if refractory
Overview of CF treatments
- Mucolytics
- Hypertonic saline, mannitol
- Inhaled dornase alfa/pulmozyme - ABx
- Staph prophylaxis <2yrs
- 2/52 augmentin if URTI when staph colonised
- If pseudomonas or infection when colonised 2/52 ciprofloxacin - Bronchodilators
- Gene modulators
- Ivacaftor (>1yr): Class 3 (G551d)
- Lumicaftor-Ivacaftor (>12yrs) : Class 2
- Tezacaftor-Ivacaftor (>12yrs): Class 2
CF pancreatic disease- endocrine
CFRDM
- Insulin deficiency from destruction of islet cells
Presents later >10yrs (20-50% by early adulyhood)
- Initially OGTT +ve then HbA1c elevated, NO ABx positive, less DKA & microvascular/macrovascular Cx
CF biliary disease
NAFLD 70%
Liver disease- severe 10-15%, dysfunction up to 30% <15yrs
Liver disease independent of genotype but is associated with meconium ileus + pancreatic insufficiency
CF pancreatic disease - exocrine
> 85% of children- common in F508del
- Most present in first year of life
- Supplement with pancreatic enzymes, fat soluble vitamins
What constitutes a positive sweat test
(in infant >2weeks)
>60 mEq/L of chloride diagnostic – lower in infants 30-40 mEq/L
- Will require DNA testing/repeat sweat test if unyeilding genetic Ix
What constitutes a positive sweat test
(in infant >2weeks)
>60 mEq/L of chloride diagnostic – lower in infants 30-40 mEq/L
If positive:
- Will require DNA testing/repeat sweat test if unyeilding genetic Ix
Findings of CF on CXR
Hyperinflation, bronchial thickening, lymphadenopathy, extensive bronchiectasis with lobar atelectasis
Findings of CF on PFTs
Early- decrease in MMEF 25-75%
Reduced FEV1, FEV1/FVC with bronchodilator response
As disease progresses more restrictive pattern
Findings of CF on PFTs
Early- decrease in MMEF 25-75%
Reduced FEV1, FEV1/FVC with bronchodilator response
As disease progresses more restrictive pattern
Relationship mec ileus to CF
10-20% of newborn infants with CF have meconium ileus
Frequency greater (=30%) among siblings born subsequent to a child with meconium ileus
Conversely 80—90% of individuals with meconium ileus have CF
Percentage of male infertility in CF
> 90% of males azoospermic due to failure of development of the Wolffian duct structures
HRCT appearence of bronchiectasis
HRCT gold standard for diagnosis
- Key radiographic criteria = broncho-arterial ratio
Other: tram lines, signet ring appearance]Lower lobes most commonly affected
Congenital causes of bronchiectasis
Williams-Campbell syndrome = absence of annular bronchial cartilage
Marnier-Kuhn syndrome = congenital tracheobronchomegaly- connective tissue disorder
Diagnostic criteria for bronchiectasis
Clinical and imaging criteria
Recurrent (>=3 episodes) wet or productive cough, each lasting >4 weeks, with or without other features
Exertional dyspnoea
Recurrent chest infections
Growth failure
Clubbing
Hyperinflation or chest wall deformity
Presence of characteristic radiographic features on HRCT
What triad of sx is seen in Kartagener Syndrome
Kartagner triad = 1) situs inversus totalis 2) chronic sinusitis 3) bronchiectasis
Mx of acutely toxic child w bacterial tracheitis/epiglottitis- stable.
- Nebulised adrenaline & dexamethasone
- Minimise handling
- IV ceftriaxone
- Prepare for intubation/PICU support (would consider earlier if haemodynamic instability)
Features of mycoplasma pneumonia- inc. CXR findings.
School aged child
Malaise, low grade fever, headache, +/- cough/dyspnoea
Not responding to normal ABx
CXR findings variable- peribronchial intestitial infiltrates/nodular opacification
Dx of this CXR?
Pneumatocoele
- Thin/smooth walled collection with air-fluid level
- Complication of severe bacterial pneumonia
- Often no additional therapy needed/asymptomatic
Dx of this CXR?
Lung Abscess
- Rare in children, unless underlying conditions
- Thick walled, purulent material- destruction of lung parenchyma
- Bugs: Staphylococcus, E.Coli, Klebsiella pneumoniae, Pseudomonas, fungal in immunocompromised
- Total 4-6wks ABx, 2-3wks IV
Dx of this CXR?
Hyatid cyst
- Echinococcus (granulosuus most common, multilocaris- most likely in lung) tapeworm
- Human is intermediate in life cycle- hatch babies into us then are ingested by definitive host to form tapeworm
- Often asymptotic
Dx of this CXR?
Cryptococcus pneumonia
- Encapsulated yeast
- Immunocompromised host
- C.Neoformans- asymptomatic then pneumonia/meningitis
- CXR: poorly defined mass lesions, pulmonary nodules, and, rarely, pleural effusion.
CF class 1 mutation, genes & Rx
No protein production
- Premature stop codon
- G542X, W1282X, R553x
GWR- great work retard, not even made
CF class 2 mutation, genes & Rx
Defect in processing
- Trapped, does not reach membrane
F508del
(N1303K, I507del)
FNI- fucking no idea- lost in the cell
CF class 3 mutation, genes & Rx
Regulation defect
- Reaches membrane but does not work
G551D
(S549N,V520F)
GSV- can’t shoot a goal
CF class 4 mutation, genes & Rx
Reduced Cl transport
- Ion channel opening faulty
R117H
D115H
R347P
RDR- registered day rest (tradies work less hard)
CF class 5 mutation, genes & Rx
Splicing defect
- Insufficient production
A455E - Ass, I have no ass, theres not enough protein
CF gene modulators & mutations effective on
What does DLCO measure?
Measures the ability of the lungs to transfer gas from the inspired air into the bloodstream.
- Pulmonary interstitial disease/vasculitis (conditions that may affect gas transfer)
↓ DLCO
- Increased membrane thickness: APO/fibrosis/ILD
- Decreased perfusion: PE/vasculitis
- Increased perfusion: hemorrhage (GPA/Goodpastures)/exercise
- Decreased 02 carrying: anaemia
- Decreased lung volume: RLD
Function/method of delivery of Dornase Alfa
Recombinant DNAse
- Mucolytic/breaks up respiratory secretions
- Inhaled/nebulised
What is the Herring Breuer reflex?
Prevents lung over-inflation
Stretch receptors respond to excessive stretch
- Inhibit inspiration
-active within the tidal volume range throughout the first year of life
Indications for PSG?
- Night time snoring, or WOB
- Daytime symptoms
- Narcolepsy
- Paroxysmal events during sleep – E.g. seizures, atypical parasomnias
- Predisposing diagnosis – E.g. Trisomy 21, CLD
- NM disease
- Nocturnal oxygen, CPAP, ventilation
- Tracheostomy decanulation
Blood test findings in narcolepsy?
HLA-DQB1*06:02 haplotype and low cerebrospinal fluid orexin (hypocretin)
Dx on this CXR?
Pulmonary fibrosis
Dx of this spirometry pattern?
Neuromuscular disease
When is a preventer indicated in kids >6yrs?
- Freq intermittent (<6wks)
- Persistent- day asthma once a week, night 2x per month
- Severe flare ups
Low, med and high dose ICS for teenagers
Fluticasone
Low 100–200
Med 250–500
High>500
Beclomethasone
Low 100–200
Med 250–400
High >400
Risk factors for thunderstorm asthma (severe episode, death)
Risk factors for thunderstorm asthma (severe episode, death)
When to start a preventer adult/adolescent?
- asthma symptoms twice or more during the past month
- waking due to asthma symptoms once or more during the past month
- an asthma flare-up in the previous 12 months.
What age range is a spacer appropriate for?
2-7 yrs
(younger infants consider face mask)
Teenagers- inhaled via spacer may lead to greater increase in HR
When is a preventer considered in 1-5yrs?
Mild flares
- Consider if <6-8wks
- If sx 1x per week 2x night/mo
Moderate flares
- If <6-8wks
Life threatening
- Even if >6mo
Dx on this CXR?
Complex pneumatocoele
- Complication of pneumonia
- Tension physiology- midline shift
Dx on this CXR?
CPAM
Dx on this CXR?
Sequestration = systemic blood supply
Dx on this CXR?
Congenital lobar emphysema
Dx on this CXR?
Bronchogenic cyst
Dx on this CXR?
Dx on this CXR?
Mx of lymphatic effusion? (chylothorax)
Medical Mx
- MCT milk formula (directly absorbed into portal venous system)
- TPN
- Somatostatin/octerotide- reduces intestinal BF, pancreatic and biliary secretions/lymphatic circulation
Surgical (if persistent)
- Pleurodesis
- IP shunt
- Thoracic duct ligation
Types of apnoea- findings on PSG
Central apnoea = loss of respiratory muscle movement and decreased nasal air flow followed by a desaturation event.
Obstructive apnoea = decreased nasal air flow with increased respiratory and abdominal muscle movement +/- desaturation event.
Physiologic vs anatomic dead space
Physiologic dead space = the volume of gas that does not eliminate carbon dioxide.
Anatomic dead space = the volume of the
conducting airways.
Risk factors for pseudomonas infection in CF?
- Recent broad spectrum ABx
- History of prolonged hospitalisation/LRTI
- Invasive devices
- Immunosuppression
- Current/prev ICU admission
Comorbidities
- DM
- Renal disease
- Lung disease
- Tumors/transplant/dialysis
- Immunosuppression
Causes of bronchiolitis obliterans?
- Post infectious: Adenovirus, Mycoplasma pneumoniae
- Drugs e.g. Penicilliamine
- Autoimmune:
- SLE, RA, Scleroderma
- GVHD after BMT
- Lung transplantation.
- Noxious fume inhalation e.g.
diacetyl (popcorn lung)
Congenital causes of chylothorax
Lymphatic malformations
Downs/Noonan’s syndrome
Common site of FB aspiration?
Right larger and more vertical – aspirated matter lodges in right bronchus
Impact of COX1 on asthma?
Thought to cause a deficiency in the protective bronchodilator/ antiinflammatory prostaglandins, and an excess of proinflammatory/ bronchoconstrictive leukotrienes.
Differences in sleep stages
NREM 20%
Stage 1 = light, easy to rouse
Stage 2 = sleep spindles/K complexes, difficult to rouse, important for memory
Stage 3 & 4 = higher voltage waves/ slow wave sleep- more difficult to rouse
REM 80%
- Desynchronized/low voltage
- Sawtooth patterns
- Muscle atonia with rapid eye movements
