Respiratory Flashcards
Asthma attack history
Acuity of onset Potential trigger Regular medication Frequency of preventer use and attacks Frequency of oral steroid use Previous ED/GP attendances Social impact
Pathophysiology of asthma
Dendritic cells present allergens to Th2 type T-cells
Humoral immune system activated
Mast cells, eosinophils, dendritic cells proliferation
Inflammatory process, bronchoconstriction
Role of leukotriene C4 and histamine in asthma attack
Histamine increases production of an exudate
Leukotriene C4 is directly toxic to epithelial cells
Risk factors for asthma
Genetic: asthma/atopy in parents or siblings
Environmental factors: low birth weight, prematurity, parental smoking
Viral bronchiolitis in early life
Atopic dermatitis
Precipitating factors for asthma
Cold air and exercise Atmospheric pollution NSAIDs increase leukotriene production BB: prevent bronchodilation through catecholamines Exposure to allergens
Pattern of wheeze in asthma
Infrequent episodic wheezing lasting a few days, no symptoms at night
Frequent episodic wheezing (2-6weekly)
Persistent wheezing: wheeze and cough most days and disturbed nights
Preschool wheeze clinical patterns
RSV
Episodic viral wheeze
Multiple trigger wheeze
Wheezing episode preceded by coryzal symptoms
Asthma diagnosis history
Age at onset of symptoms Frequency of symptoms Severity of symptoms: at night, effect on life Previous treatments tried Any hospital attendances Presence of food allergies Triggers Disease history FH of atopy
Examination of a child with asthma
Finger clubbing: CF, bronchiectasis
Chest shape: hyperinflated chest indicates poor asthma control
Chest symmetry
Breath sounds
Presence of crepitations: not suggestive of asthma
Presence of wheeze
Examination of throat to check for tonsillar enlargement
Asthma investigations
Spirometry: FEV1:FVC<0.7 PEFR Bronchial provocation tests: histamine or metacholine Exercise testing Skin prick testing Exhaled nitric oxide CXR
What other investigations should be performed if there is doubt of a diagnosis of asthma?
Oesophageal pH to assess for GORD
Bronchoscopy to exclude structural abnormality
Chloride sweat test to exclude CF
Nasal brush biopsy to exclude primary ciliary dyskinesia
Serum IgG, IgA and IgM and response to vaccinations
HRCT to exclude bronchiectasis
Sputum culture
Signs of good asthma symptoms control
Full school attendance No sleep disturbance <2/week daytime symptoms No limitations of daily activities No exacerbations Using salbutamol <2/week Maintaining normal lung function
Omalizumab in asthma
Monoclonal antibody for IgE
Reduces free IgE in the blood
Given to children with persistent poor control
If evidence of allergic sensitisation to a perineal aeroallergen and a raised serum total IgE
Causes of wheeze in children
Respiratory infections: bronchiolitis, bronchiolitis obliterans
Airway abnormalities: bronchomalacia, chronic lung disease of prematurity
Foreign body inhalation
Mild/moderate asthma attack
SpO2 >92% RR >30 (>5), >40 (<5) No or minimal accessory muscle use Feeding well or talking in full sentences Wheeze
Severe asthma attack
SpO2<92% PEFR 33-50% predicted RR >30 (over 5), >40 (<5) Too breathless to feed or talk HR >125 (>5), >140 (<5) Use of accessory muscles Audible wheeze
Life-threatening asthma
SpO2<92% PEFR <33% predicted Silent chest Poor respiratory effort Altered consciousness Agitation/ confusion Exhaustion Cyanosis
Immediate management of asthma attack
Oxygen, 94-98 aim
Bronchodilators
Ipratropium bromide (anti-muscarinic) if no or poor response to inhaled SABA
Corticosteroids: short 3 day course or steroids should be commenced, oral prednisolone is first line. IV hydrocortisone if child is vomiting lots
Second-line management of asthma attack
IV salbutamol
Magnesium sulphate
Safe discharge criteria for asthma
Bronchodilators with spacer at intervals of 4-hourly or more
SaO2>94% air
Inhaler technique assessed/taught
Written asthma management plan given and explained to parents
GP should review child 2 days after discharge
Acute cough
<4 weeks
Viral, bacterial infection
Pertussis
Prolonged acute cough
4-8 weeks
Post-viral cough
Children recovering from complicated pneumonia
DD of chronic wet cough (>8weeks)
Persistent bacterial bronchitis Rhinitis and post-nasal drip GORD Bronchiectasis (CF vs non-CF) Primary ciliary dyskinesia (PCD) Immune problems- recurrent/unusual infections Recurrent aspiration
Approach to patient with chronic cough
History of infection Nasal symptoms Failure to thrive Wheeze Response to previous symptoms Atopy CXR Bloods- immune screen, allergy markers SALT Lung function test
What is involved in an immune screen?
T-cell sub sets
Antibody response
Ig
What are the allergy markers?
Eosinophils
IgE
SIgE
Features and treatment of rhinitis with post-nasal drip?
Throat clearing Snoring Blocked nose Bad breath Worse in morning and clears through day
Steroid nasal spray
Antihistamine
GORD features and treatment
Younger child
Vomits
Better when upright
Trial of PPI
Protracted bacterial bronchitis
Persistent bacterial infecton in lower airway
Presence of wet cough (>4 weeks)
Absence of symptoms or signs (i.e. specific cough pointers) suggestive or other causes
Cough resolves following a 2-4week course of an appropriate oral antibiotic
Symptoms of protracted bacterial bronchitis
Chest pain
History suggestive of inhaled foreign body
Exertional dyspnoea
Failure to thrive
Feeding difficulties
Cardiac or neuro developmental abnormalities
Recurrent sinopulmonary infections
Immunodeficiency or epidemiological risk factors for exposure to TB
Signs of protracted bacterial bronchitis
Respiratory distress
Digital clubbing
Chest wall deformity
Auscultation crackles
Tracheobronchomalacia
Floppy airways: flaccidity of supporting cartilage
Congenital, extrinsic compression, acquired
Treatment: nothing, prophylactic antibiotics, CPAP, surgery
Prognosis very good
Causes of bronchiectasis
CF Post-infectious Immunodeficiency Ciliary dyskinesia Aspiration
Diagnosis of bronchiectasis
HRCT
Treatment of bronchiectasis
Prophylactic Ax Physiotherapy Aggressive LRTI treatment Nutrition Regular monitoring, including lung function
CF diagnosis
Screening
Sweat chloride
Genotyping
Pathophysiology of CF in lungs
Defective CFTR protein on airway epithelial cells and submucosal glands
Decreased secretion of chloride and increased reabsorption of sodium and water
Reduced amount of water in secretions
Reduced airway surface liquid: important for immunology and mucocilialry escalator
Decrease mucus clearance
Ideal for bacteria, inflammation
CF manifestations
Recurrent chest infections, chronic wet cough
Exocrine pancreatic insufficiency
Failure to thrive
Neonate- meconium ileus, protracted jaundice, electrolyte abnormality
Intestinal obstruction
Male infertility-blockage of vas
Pathophysiology of pancreatic insufficiency in CF
Duct occluded in-utero causing permanent damage to exocrine pancreas
CF-related DM
GI tract pathophysiology in CF
Small intestine secretes viscous mucus
Bowel obstruction in-utero
Meconium ileus
Cholestasis in biliary tree
Neonatal jaundice
Later in life:
Distal intestinal obstruction syndrome
CF-related liver disease
Reproductive tract pathophysiology in CF
Congenital abscence of vas deferens
Clinical presentation of CF in neonates
Meconium ileus- abdominal distension, delayed passage of meconium and bilious vomiting in first days of life
Failure to thrive
Prolonged neonatal jaundice
Clinical presence of CF in infancy
Failure to thrive
Recurrent chest infections
Pancreatic insufficiency; steatorrhea
Childhood presentation of CF
Rectal prolapse
Nasal polyps
Sinusitis
Adolescent presentation in CF
Pancreatic insufficiency; diabetes mellitus
Chronic lung disease
DIOS, gallstones, liver cirrhosis
History of a patient with CF
Early treatment of infection and optimisation of nutrition
Persistent/recurrent productive cough
Failure to thrive
Complaints of bowel symptoms: steatorrhoea, constipation
Rectal prolapse
Nasal polyps
Examination of a patient with CF
Finger clubbing
Nasal polys
Hyperinflated chest, crepitations, portacath
Faecal mass in abdomen, ileostomy scar from meconium ileus
Diagnosis of CF
Fitting clinical history
Positive chloride sweat test
Investigations in CF
CXR for hyperinflation and bronchial thickening
Chloride sweat test
Microbiological assessment, e.g. cough swab/sputum
Glucose tolerance test
LFT and coagulation
Bone profile
LFT: spirometry and lung clearance index
Faecal elastase to assess pancreatic function
Chest CT for bronchiectasis
Genetic analysis
The chloride sweat test
Measures electrolyte concentration in sweat, >60mmol/L
Pilocarpine iontophoresis
Need a second positive test or genetic mutation identification to diagnose
CF airway clearance and chest symptoms management
Twice-daily physiotherapy
Increased airway secretion clearance, will reduce airway obstruction and minimise risk of infection
DNase: inhaled and reduces viscosity of mucus by digesting DNA which is abundant in the sputum of patients with CF
Hypertonic saline: can aid airway clearance
Nourishment and exercise for CF Mx
Pancreatic enzyme supplementation (Creon) with fat meals
ADE vitamin supplements
Monitor growth
Build-up milkshakes
Enteral feeding via gastrostomy if needed
Managing/ preventing airway infections in children with CF
Common causative organisms; staphylococcus aureus, Haemophilus influenzae, pseudomonas aeruginosa
Patients need continual microbiological assessment to identify organisms colonised
Sputum cultures
Treat infections with 2 weeks of ax
Give regular azithromycin
Prophylactic ax in <3years
Chronic pseudomonas treat with inhaled ax due to biofilms
Side room
Annual CF review
Respiratory paediatrician Dietician Physiotherapist CF specialist nurse Review of clinical symptoms, ax, microbiology Bloods: FBC, renal function, LFTs, vitamines A,D,E, clotting profile, HbA1c LFTs CXR is normally performed >12 oral glucose tolerance test
Non-resp complications of CF
Rectal prolapse DIOS: distal ileal obstruction Cholestasis Gallstones Liver cirrhosis CF-related diabetes Delayed puberty: reduced bone mineral density Arthritis Infertility
Respiratory complications of CF
Allergic bronchopulmonary aspergillosis Bronchiectasis Haemoptysis Pulmonary hypertension and right heart strain Pneumothorax Respiratory failure Nasal polys
Paediatric long term ventilation
<17
Medically stable
Requires a mechanical aid for breathing with invasively by tracheostomy or by non-invasive ask interface for all or part of the 24h day
For longer than 3 months
Causes of stridor in children
Croup
Acute epiglottitis
Inhaled foreign body
Laryngomalacia
Causes of OSA in children
Enlarged tonsils and adenoids
Obesity and Down;s syndrome: makes airway more collapsible
Abnormal facial structure
Narrow, floppy, soft airways (laryngomalacia)
Muscular dystrophy or cerebral palsy
OSA symptoms
Snoring and pauses in breathing followed by gasps or snorts Daytime sleepiness Difficulty putting on weight Mouth breathing Nasal speech Hyperactivity Irritable
OSA assessment
Parental observation Oxygen saturations CO2 levels Breathing movements Heart rate and rhythm Airflow Video and sound recording
OSA treatment
Adenotonsillectomy
Nasal inhaled corticosteroid sprays or drops
What is croup?
Acute laryngotracheobronchitis
Common viral childhood illness
Harsh barking cough, stridor, hoarseness of voice, fever
Epidemiology of croup
6months-3 years
Peak incidence at 2 years
Pathophysiology of croup
Mucosal inflammation anywhere between nose and trachea
Parainfluenza virus is most common
Impaired movement of vocal cords creates characteristic barking cough
Potential causative organisms for croup
Parainfluenza virus Respiratory syncytial virus Adenovirus Rhinovirus Enterovirus Measles Meta pneumovirus Influenza A and B Mycoplasma pneumoniae
Risk factors for croup
Male gender
Autumn and spring season
C/C variant of the CD14 C-159T gene
History of a child with croup
1-4 day history of non-productive cough, rhinorrhoea and fever
Progressing to a barking cough and hoarseness
Symptoms worst at night
Red flags for resp failure: drowsiness and lethargy
Clinical features from examination of croup
Stridor
Decreased airflow
Resp distress: tachypnoea, intercostal recession
Red flag for respiratory failure: cyanosis, lethargic/decreased level of consciousness, laboured breathing, tachycardia
Mild croup
Occasional barking cough
No audible stridor at rest
No suprasternal, or intercostal recession
Child is happy and will drink, eat and play
Moderate croup
Frequent barking cough
Audible stridor at rest
Suprasternal and sternal wall retraction at rest
Child isn’t distressed or agitated and will still show interest in surroundings
Severe croup
Frequent barking cough Prominent inspiratory stridor at rest Marked sternal wall retractions Child will appear distressed/ agitated or lethargic or restless Tachycardia, hypoxaemia
Croup vs epiglottis
Days vs hours Coryza vs no prior features Barking cough vs slight/if any Can drink vs no feeding Mouth closed vs drooling saliva Non toxic vs toxic Fever <38.5 vs >38.5 Rasping stridor vs soft stridor Hoarse voice vs weak or silent
Investigations for croup
FBC, CRP, U&Es
CXR: rule out inhaled foreign body
Pulse oximetry
When would you consider admission in a croup child?
<6 months
Previous history of severe airway obstruction
Immunocompromised
Have had inadequate fluid intake
Have had a poor response to initial treatment
The diagnosis is uncertain
Significant parental anxiety
Advice to parents for home-managed croup:
Symptoms resolve within 48hours but can last to one week
Paracetamol or ibuprofen to control pain and fever
No Ax needed
Ensure that child has adequate fluid intake
Seek urgent medical advice if symptoms worsen: high fever, stridor, heart rate (bacterial tracheitis)
Call ambulance if signs of respiratory failure
When should immediate hospital admission occur for croup?
If child has moderate/severe croup or impending respiratory failure
Suspect serious disorder caused by infection, e.g. peritonsillar abscess, laryngeal diphtheria, non-infectious cause (foreign body, angioneurotic oedema)
Treatment for croup
Single dose of oral dexamethasone (0.15mg/kg) or oral prednisolone (1-2mg/kg body weight)
Nebulised adrenaline to provide temporary symptomatic relief
Ensure child is calm
Oxygen therapy as required
Contact ENT and an anaesthetist if there is need for airway support
Complications of croup
Lymphadenitis Otitis media Dehydration Bacterial superinfection resulting in pneumonia or bacterial tracheitis Pulmonary oedema Pneumothorax
When are pertussis vaccines given?
2, 3, and 4 months of age
Booster at 3 years and 4months
Pregnant women
Pathophysiology of pertussis
Bordetella pertussis
Gram-negative bacillus
Aerosol spread, very contagious
Bacteria attach to respiratory epithelium
Bacteria produce toxins which paralyse cilia and promote inflammation
Impaired clearance of respiratory secretions
Cough
Risk factors for pertussis
Non-vaccination
Exposure to infected individuals
Phases of pertussis
Catarrhal (first) phase lasts 1-2weeks
Paroxysmal (second) phase lasts for 2-8weeks
Catarrhal phase of pertussis
Rhinitis Conjunctivitis Irritability Sore throat Low-grade fever Dry cough
Paroxysmal phase of pertussis
Severe paroxysms of coughing, more common at night
Then inspiratory gasp, producing the classic whoop sound
<3 months, apnoea, vomiting after coughing
Conjunctival haemorrhages and facial petechiae due to vigorous coughing
Examination of pertussis
Low grade fever
Conjunctival haemorrhages and facial petechiae
Chest auscultation usually normal
Differential diagnosis of paroxysmal cough
Bronchiolitis/ viral respiratory infection Mycoplasma pneumonia Bacterial pneumonia Asthma Tuberculosis
Pertussis investigations
<2 weeks cough: nasopharyngeal aspirate culture or nasopharyngeal swab is recommended
>2 weeks and <5: anti-pertussis toxin IgG serology
>2 weeks and 5-17: anti-pertussis toxin detection in oral fluid
Pertussis vaccine within last year can produce a false positive
FBC: lymphocytosis (+/- elevated WCC)
Management of pertussis
Macrolides ax when cough <21 days
<1 months: clarithromycin
>1 months: azithromycin or clarithromycin
2nd line: co-trimoxazole or macrolides inappropriate
Supportive management
Cough takes 3 months to self-resolve
Avoid school or nursery until 21days cough or 5days ax
Hospital admission indicated in pertussis
<6months
Significant breathing difficulties, e.g. apnoeic episodes, cyanosis, respiratory distress, severe paroxysms of coughing
Feeding difficulties
Significant complications, e.g. pneumonia or seizures
Complications of pertussis
Secondary bacterial pneumonia
Seizures
Encephalopathy
Otitis media
Pathophysiology of bronchiolitis
Proliferation of goblet cells: excess mucus
IgE-mediated TY1 allergic reaction: inflammation
Bronchiolar constriction
Infiltration of lymphocytes: submucosal oedema
Infiltration of cytokines and chemokines
Hyperinflation, increased airway resistance, atelectasis, VQ mismatch
Risk factors for bronchiolitis
Breast fed for less than 2 months
Smoke exposure
Having siblings who attend nursery or school
Chronic lung disease due to prematurity
History of bronchiolitis
Increasing symptoms over 2-5days Low-grade fever Nasal congestion Rhinorrhoea Cough Feeding difficulty
Examination findings in bronchiolitis
Tachypnoea Grunting Nasal flaring Intercostal, subcostal or Supraclavicular recessions Inspiratory crackles Expiratory wheeze Hyperinflated chest Cyanosis or pallor
Bronchiolitis lab tests
Nasopharyngeal aspirate or throat swab- RSV rapid testing and viral cultures
Blood and urine culture if child is pyrexic
FBC
Blood gas (ABG)- if severely unwell
Bronchiolitis CXR features
Hyperinflation Focal atelectasis Air trapping Flattered diaphragm Peribronchial cuffing
Features of bronchiolitis for urgent hospital referral
Apnoea Child looks seriously unwell Severe respiratory distress, e.g. grunting, marked recessions, RR>70 Central cyanosis Oxygen sats <92%
Management steps for bronchiolitis in hospital
If <92% give oxygen
Give fluids NG/orogastric if inadequate oral intake
CPAP if resp failure
Upper airway suctioning if upper airway secretions or apnoea
When can u discharge bronchiolitis
Clinically stable
Taking adequate oral fluids
Maintaining sats >92% for more than 4 hours
Complications of bronchiolitis
Hypoxia Dehydration Fatigue Respiratory failure Persistent cough or wheeze Bronchiolitis obliterans- airways permanently damaged due to inflammation and fibrosis
Prognosis of bronchiolitis
7-10days
Most children can cough for up to 6 weeks
What is bronchiectasis?
Abnormal dilatation of airways with associated destruction of bronchial tissue
Commonly occurs as a result of CF
Pathophysiology of bronchiectasis
Inflammatory response to a severe infection
Structural damage within bronchial walls, which causes dilatation
Scarring from immune response
Scarring reduces number of cilia within bronchi
Causes of bronchiectasis
Streptococcus pneumoniae Staphylococcus aureus Adenovirus Measles Influenza virus Bordetella pertussis Mycobacterium tuberculosis Antibody defects HIV infection Ataxia telangiectasia Primary ciliary dyskinesia Post-obstructive: foreign body Youngs Yellow-nail syndrome
Primary ciliary dyskinesia
Autosomal recessive genetic defect
Reduced efficacy or complete inaction of bronchial cilia
Problems in mucociliary clearance
Increased susceptibility to low-grade infections and irritation from foreign particles
Youngs syndrome
Bronchiectasis
Reduced fertility
Rhinosinusitis
Yellow-nail syndrome
Pleural effusions
Lymphoedema
Dystrophic nails
Bronchiectasis history
Chronic, productive cough Purulent sputum expectoration Chest pain Wheeze Breathlessness on exertion Haemoptysis Recurrent or persistent infections of LRTI
Bronchiectasis examination
Finger clubbing
Inspiratory crackles
Wheezing
Bronchiectasis imaging
CXR: bronchial wall thickening or airway dilatation
High resolution CT: gold-standard, bronchial wall thickening, diameter of bronchus larger than that of accompanying bronchial artery (signet ring) and visible peripheral bronchi
CF: Bilateral upper lobe bronchiectasis
Post-TB: unilateral upper lobe bronchiectasis
Foreign body inhalation: focal lower lobe bronchiectasis
Bronchiectasis investigations
Chloride sweat test FBC with leukocyte differential Immunoglobulin panel Specific ab levels to vaccinations, e.g. pneumococcal or Hib If bronchoscopy: ciliary brush biopsy HIV test Microbiology Lung function: spirometry obstructive in severe
Management of bronchiectasis
Chest physiotherapy
Ax
Bronchodilators if wheeze present
Follow-up
Complications of bronchiectasis
Recurrent infection Life-threatening haemoptysis Lung abscess Pneumothorax Poor growth and development
