Respirology Flashcards
What is CF (genetics, mechanism, clinical features)?
How do you diagnose it?
Management?
Genetics: gene that codes for the CFTR protein (majority are ΔF508) Inheritance: Autosomal Recessive
- Mechanism:
- CFTR dysfunction = ↓Cl secretion and ↑Na absorption → dehydrated/viscous mucus
- Clinical Features (I’m CF Pancreas)
- Infertility
- Meconium ileus
- Cough
- Failure to thrive
- Pancreatic insufficiency
- Asthma (refractory)
- Nasal polyps
- Clubbing
- Rectal prolapse
- Electrolyte abnormalities (metabolic alkalosis, ↓Na, ↓Cl, ↓K)
- Atypical organisms from sputum
- Sludge (cholelithiasis/cystitis, pancreatitis, sinusitis)
- Respiratory*: bronchiectasis, pneumothorax, respiratory failure
- Gastrointestional*: DIOS, intussusception, biliary cirrhosis, hepatic steatosis, GERD, inguinal hernia, steatorrhea, fat-soluble vitamin deficiency (A, D, E, K)
Delayed puberty, hypertrophic osteoarthropathy/arthritis, amyloidosis, aquagenic palmoplantar keratoderma (skin wrinkling), hypoproteinemia
Diagnosis:
- Requires either (1 of):
- Clinical features
- Sibling with CF
- positive NBS
- AND (1 of):
- Elevated sweat chloride
- Abnormal nasal potential difference
- Identification of 2 disease-causing CF mutations
Management:
- Suppressive antibiotic therapy
- Mucociliary clearance (chest PT)
- Inhaled mucolytics (DNase if >6yo)
- Bronchodilators
- Inhaled 3%NaCl
- Antiinflammatory: NSAIDs and macrolides (3x/wk)
- Nutrition: enzyme replacement, vitamin supplements, high-fat, high protein diet, MCTs added
- Insulin PRN
- Ursodiol to prevent/treat liver disease
- CFTR modulators
- Lung transplant
List 2 features that would make you concerned for a diagnosis of Primary Ciliary Dyskinesia.
What is the diagnostic test for PCD?
Having ≥2 of the following should prompt investigations for PCD:
- Unexplained neonatal respiratory distress in a term infant
- Year-round daily cough starting <6mo
- Year-round daily nasal congestion starting <6mo
- Organ laterality defect
Diagnostic test:
- Electron microscopy of ciliary ultrastructure → Recognized ciliary ultrastructural defect
- Genetic testing → biallellic pathogenic variants in PCD-associated gene
- Contributory: Nasal nitric oxide measurement (must be available in centre, cooperative patient ≥5yo [capable of performing maneuver] and if CF is excluded) → Low nNo level
Define Asthma
Asthma is:
- paroxysmal or persistent symptoms (SOB, chest tightness, wheeze, sputum production and cough) associated with variable airflow limitation and airway hyperresponsiveness (endo/exogenous stimuli)
- Inflammation and it’s effects on airway structure are the mechanisms for development and persistence of asthma.
List 5 alternative diagnoses to a child you suspect has asthma.
- Cystic fibrosis
- Foreign body aspiration
- Chronic aspiration
- Primary Ciliary Dyskinesia
- Infectious adenopathy (TB, fungal)
- Pulmonary infections (viral bronchiolitis, pneumonia)
- CLD of prematurity
- Rare interstitial lung disease
- Congestive Heart Failure (CHF)
- GERD
- Allergic reaction
- Large airway obstruction
- Extrinsic - tumour (mediastinal mass), vascular ring
- Intrinsic - laryngeal web, tracheoesophageal fistula (TEF)
- Wall abnormality - CNS disorder
List 5 indications of asthma control in school-aged children
Describe the differences in monitoring control for “preschool” children (1-5yo)
- Daytime symptoms <4 days/week
- Nighttime symptoms <1 night/week
- Normal physical activity
- Mild, infrequent exacerbations
- No absence from school/work
- Requiring <4 doses/week of SABA (no longer excludes pre-exercise beta-agonist use)
- FEV1 or PEF is ≥90% personal best
Differences
- Persistent symptoms:
- Daytime symptoms ≥8 days/month
- SABA use ≥8 days/month
- ≥1 night awakening due to symptoms/month
- Severe exacerbations (requiring rescue corticosteroids or hospital admission
Same
- Absence from usual activities due to asthma symptoms
- No exercise limitation
What is your initial management for a preschool child (1-5yo)?
Describe the progression for escalation of management.
Initial
- Start management if:
- No red flags for alternative diagnosis AND
- ≥1 document asthma-like exacerbation OR
- ≥2 episodes asthma-like symptoms AND no documented signs of obstruction or improvement to therapy
- Asthma education (environmental control + action plan)
- Current signs of obstruction (wheeze, initial ↓AEBB→↑RR→ prolonged expiration→accessory muscle use→hypoxemia →altered LOC)
- Mild intermittent symptoms
- SABA PRN
- Persistent symptoms OR moderate/severe exacerbations (hospital or requiring corticosteroids)
- Low-dose ICS + SABA PRN
- Mild intermittent symptoms
- No signs of obstruction
- Monitor and reassess when symptomatic
- +/- SABA PRN x 3mos,
- If documented signs of airflow obstruction AND convincing response to SABA = ASTHMA
- If unclear, stop trial, if deterioration = ASTHMA
- +/- SABA PRN x 3mos,
- Monitor and reassess when symptomatic
- If frequent symptoms OR ≥1 moderate/severe exacerbation
- MEDIUM dose ICS x 3 mos + R/A at 6wks AND 3 mos, if clear improvement = ASTHMA
- If unclear improvement, stop challenge - if deteriorates = ASTHMA
- MEDIUM dose ICS x 3 mos + R/A at 6wks AND 3 mos, if clear improvement = ASTHMA
GET INFLUENZA VACCINATION
Escalation
If initially mild → low dose ICS → Medium dose ICS → asthma specialist (add LABA/LTRA)
How do you diagnose asthma in preschoolers (1-5yo) vs school-aged children/teenagers?
Preschool
- Documentation of signs/symptoms of airflow obstruction
- Reversibility of obstruction (improvement of these symptoms with asthma therapy [SABA +/-)
- No clinical suspicion of an alternative diagnosis
Recurrent (≥2) asthma-like exacerbations
School-aged/Teens
- Clinical symptoms + Objective evidence (below)
- Spirometry: obstruction (↓FEV1/FVC) + bronchodilator response (↑FEV1 by ≥12%)
- Peak flow: ↑≥20% following SABA
- Methacholine
- +ve = <4mg/mL
- Borderline = 4-16mg/mL
- Negative = >16mg/mL
List 3 reasons for referring a preschool (1-5yo) asthmatic to a respirologist or specialist
- Diagnostic uncertainty or suspicion of comorbidity
- ≥2 exacerbations needing rescue PO CS or hospitalization or frequent symptoms (≥8 days/month) despite moderate (200 -250µg) daily doses ICS
- Life-threatening event (ICU admission)
- Need for allergy testing
- Other considerations
- Parental anxiety
- Need for Reassurance
- Additional education
What is the most frequent cause of Recurrent Cough?
Recurrent URTIs with postnasal drip
List 4 causes of stridor
- Infection*: Tracheitis, croup
- Intrinsic:* Laryngomalacia, Tracheal Stenosis
- Extrinsic:* Vascular Ring, Tumour
Other: Foreign body
What type of spacer is indicated for 1-3yo, 4-5yo
Describe the pyramidal progression of asthma management for school aged children.
- Confirm diagnosis
- Environmental Controls, Education and Written Action Plan
6-11yo: SABA PRN→Low ICS→↑Med ICS→add LABA/LTRA
≥12yo: SARA PRN→Low ICS→add LABA →Add LTRA→Med ICS +LTRA+LABA
What are indications that a child may have asthma later in life?
Modified Asthma Predictive Index (mAPI)
- For patients ≤3yo
- MUST HAVE
- ≥3 episodes of wheezing/year
- 1 MAJOR or 2 MINOR criteria
MAJOR
- Parental Asthma (dx by MD)
- Eczema (dx by MD at 2 or 3)
MINOR
- Allergic rhinitis (dx by MD at 2 or 3)
- Wheezing apart from colds
- Eosinophilia (≥4%)
What are the most common organisms seen in a baby, toddler and school-aged child with cystic fibrosis?
Baby: Staphylococcus aureus
Toddler: Haemophilus influenzae
School-aged child: Pseudomonas aeruginosa, Klebsiella pneumoniae, Stenotrophomonas maltophilia, Burkholderia cepacia
How can parents minimize transmission of RV to their infants?
- Hand hygiene
- Avoid contact of high-risk children with people with respiratory tract infections
- Breastfeeding
- Avoidance of cigarette smoke
What are the indications for RSV prophylaxis?
<6mo at start of season
- <30wks GA WITHOUT CLD
- <36wks GA in remote communities
- Term Inuit infants living in communities with documented persistent high rates of RSV hospitalization
<12mo at start of season
- HD-significant CHD or CLD (need for O2 at 36wks GA)
- Consider for those <24mo on home O2, severely immunocompromised or prolonged hospitalization for severe pulmonary disease
If they get an RSV infection, stop the immunizations.
If being discharged home for first time during RSV season, give first dose before discharge.
What are 2 risk factors for severe RSV?
Describe features of vocal cord dysfunction
Intermittent stridor (with wheezing) that accompanies physical activity and is not responsive to asthma therapies.
Investigated with laryngoscopy during exercise challenge test if symptoms are successfully elicited. (would cause a truncated loop on spirometry)
Management: SLP and behaviour modification can be therapeutic
List 4 indications for hospitalization of a child with RSV infection
- Risk for progression to severe disease
- Respiratory status - tachypnea (RR>70), ↑WOB, O2 required, cyanosis or history of apnea
- Ability to maintain adequate hydration
- Family’s ability to cope at home
- Infant at risk of severe disease
- Prematurity <35wks
- Age <3mo
- HD-CHD
- Immunodeficiency
List 2 indications for discharge from hospital with bronchiolitis.
- Improvement of breathing and tachypnea
- Maintaining SpO2 >90% without O2 or stable for home oxygen therapy
- Adequate PO feeding
- Education provided and appropriate follow-up arranged
What 2 treatments for bronchiolitis are recommended by CPS?
Which have equivocal evidence?
What treatments should be considered if there is no improvement?
Recommended: Hydration, oxygen
Equivocal: Epi nebs, nasal suctiniong, combined Epi/dex
No improvement: humidified, heated, high-flow nasal oxygen (HHHFN), nebulized epinephrine
If high-risk in acute phase of illness, place continuous SpO2 on. Low-risk children to have intermittent monitoring or spot checks.
When is a CXR indicated with bronchiolitis?
- Diagnosis of bronchiolitis is unclear
- Rate of improvement is not as expected
- Severity of disease raises other diagnostic possibilities, such as pneumonia
In a pleural effusion, what 3 findings are expected in an empyema
LIGHT’S CRITERIA
Transudate (pleural fluid) - MUST FULFILL ALL CRITERIA
- Serum Protein <0.5
- Serum LDH <0.6
- Pleural fluid LDH <2/3 ULN
Exudate - MUST FULFILL ≥1 CRITERIA
- Serum Protein ≥0.5
- Serum LDH ≥0.6
- Pleural fluid LDH >2/3 ULN
What are the most common triggers of an asthma exacerbation in the paediatric population?
Viral respiratory tract infections
Exposures to allergens
Suboptimal control of asthma as a baseline
Describe the objectives of management of an asthma exacerbation in the ED
- Immediate and objective assessment of severity → PRAM
- SpO2
- Risk of ICU/death
- Spirometry [if able]
- Prompt and effective medical intervention to decrease respiratory distress and improve oxygenation
- Supplemental O2
- SABA MDI w/spacer [<20kg: 5 puffs; >20kg: 10 puffs; nebs 5mg in 2mL NS x 3; continuous 0.3mg/kg/h in 4mL NS]
- SE: ↑HR, ↑glucose, ↓K; if continuous, arrhythmia
- Inhaled anticholinergic (ipratropium bromide-Atrovent) [<20kg: 3 puffs/neb 0.25mg; >20kg: 6 puffs/neb 0.5mg]
- Corticosteroids
- Assess treatment response
- If poor:
- MgSO4 (25-50mg/kg [max 2g]IV over 20min
- SE: ↓BP
- Heliox
- Intubate
- ICU: IV aminophylline
- MgSO4 (25-50mg/kg [max 2g]IV over 20min
- Consider other modalities of treatment→anaphylaxis
- If poor:
- Appropriate disposition after ED management
- Arrange proper follow-up
- Corticosteroids x 3-5 days
- Review ICS dosing and adjust PRN, start if not taking
- SABA q4h until resolved → PRN
- Give written asthma action plan
- Review techniques of spacer maintenance and use
- F/U PCP, asthma clinic within 2-4 weeks
- If ICU → asthma specialist (allergist or respirologist)
List 2 risk factors for ICU admission/death in an asthmatic patient
- Previous life-threatening events
- Admissions to ICU
- Intubation
- Deterioration while already on systemic steroids
List 2 indications for admission to hospital in an asthma exacerbation.
List 2 indications for discharge for this patient.
Admission
- Ongoing supplemental O2 requirement
- Persistently ↑WOB
- SABA needed >q4h after 4-8h treatment
- Deterioration on systemic steroids
- Distance from home, comorbid conditions (anaphylaxis)
Discharged
- SABA PRN
- SpO2 of 94% on RA
- Minimal or no signs of respiratory distress
- Improved air entry
List 5 conditions associated with false-positive sweat chloride results.
List 3 conditions associated with false-negative sweat chloride results
False-positive
- Eczema (atopic dermatitis)
- Ectodermal dysplasia
- Anorexia nervosa
- Malnutrition/FTT/deprivation
- CAH
- G6PD
- Hypothyroidism
- Klinefelter
- Adrenal insufficiency
- Nephrogenic DI
False-Negative
- Dilution
- Malnutrition
- Edema
- Insufficient sweat quanitity
- Hyponatremia
- CFTR mutation with preserved sweat duct function
List 3 genetic disorders or syndromes associated with Obstructive Sleep Apnea
List 5 medical conditions that can be associated with OSA.
- Midface hypoplasia (Trisomy 21, Crouzon, Apert syndrome)
- Mandibular hypoplasia (Treacher Collins, Cornelia de Lange syndrome)
- Achondroplasia
- MPSI/II
MEDICAL CONDITIONS
- Upper airway obstruction (chronic allergic rhinitis, GERD with pharyngeal reactive edema, nasal septal deviation)
- Reduced upper airway tone (muscular dystrophy, hypotonic cerebral palsy, hypothyroidism)
- Reduced central ventilatory drive (Chiari malformation, rapid-onset obesity with hypothalamic dysfunction/autonomic dysregulation)
- Meningomyelocele
- Obesity
List 5 daytime symptoms of OSA.
- Morning headaches
- Secondary enuresis
- Daytime somnolence + difficulty with morning waking
- Mood changes (depression, anxiety, irritability,)
- Behavioural issues (increased somatic complaints, aggression, impulsivity, hyperactivity, oppositional and conduct problems)
- Mouth breathing and dry mouth
- Difficulty swallowing
- Poor appetite
- Hyponasal speech
- Chronic nasal congestion or rhinorrhea
What is the gold standard test for diagnosis of OSA.
If not available, describe alternative testing options.
What is the AHI cutoff value for OSA (children/adolescent)?
Overnight Polysomnogram
ALTERNATIVE TESTING
- Nocturnal oximetry
AHI CUT OFF
- Children ≤12: AHI ≥1.5
- Adolescents >12: AHI ≥5
Describe the options for management of OSA.
1st line: tonsillectomy
- if contraindicated: nasal CS
If overweight/obese: weight loss
If ongoing symptoms after T&A: CPAP
Other:
- Positional therapy (attach firm object [tennis ball] to back of sleep garment to prevent sleeping in supine position
- Aggressive treatment of risk factors: GERD, allergies, asthma
- LTRAs if upper airway inflammation present
Identify this abnormality
CPAM (Congenital pulmonary airway malformation)
Previously called CCAM (congenital cystic adenomatoid malformation)
Management: resection if symptomatic, mass effect, infection or concern of malignant potential
Identify this abnormality
Congenital lobar emphysema
Affects upper>lower
Caused by intrinsic or extrinsic obstruction to lobar bronchus
Management: clinical observation with serial XRs
if any kind of compression, infections or wheezing it may be resected
Identify this abnormality
Pulmonary sequestration
Can be associated with CHF, recurrent infections
Aberrant arterial supply.
No communication with functional airways
Extralobar sequestrations are associated with CDH
Need CTA to diagnose - CT without contrast not helpful
Management: if frequent infections - require resection after adequate Abx, all should be resected once identified
What are 4 long-term consequences of OSA?
- Cor pulmonale
- Neurocognitive impairment
- Behavioural problems
- Failure to Thrive
What are the first choice antimicrobials for a CF exacerbation in a teenager?
Tobramycin
Ceftazidime
You are seeing a teenager with cystic fibrosis. He’s been complaining of worsening cough, chest pain, and increased sputum production. His IgE is noted to be elevated with increased eosinophils on differential.
What is the most likely diagnosis?
What is your treatment?
ABPA (allergic bronchopulmonary aspergillosis)
Extended course of systemic corticosteroids
Oral antifungal agents (itraconazole or voriconzole)
What 4 things in the medical history of an asthmatic put them at increased risk for anesthetic?
- Hospital admission within the previous year
- ED care in the past 6 months
- Previous ICU admission
- Previous IV systemic corticosteroids
What are 3 conditions that predispose causes of bronchiectasis?
- Cystic fibrosis
- Primary Ciliary Dyskinesia
- ABPA (allergic bronchopulmonary aspergillosis)
- Recurrent pneumonia
- Bronchiolitis obliterans
- Immunodeficiency (HIV, hypogammaglobulinemia, CVID)
What is the most common cause of uncomplicated bacterial pneumonia?
What is the most common cause of an empyema? What other pathogens are commonly seen?
Streptococcus pneumoniae (for both)
Empyema (other pathogens): Staph aureus, GAS
List 3 physical examination findings seen with pneumonic consolidation
- Dullness to percussion
- Increased tactile fremitus
- Reduced normal vesicular breath sounds
- Increased bronchial breath sounds
List 3 indications for hospitalization with pneumonia
- Inadequate oral intake
- Intolerant to oral therapy
- Severe illness or respiratory compromise
- Complicated pneumonia
- <6mo
Describe the recommended antimicrobials for uncomplicated pneumonia in the following scenarios:
- Stable (outpatient/hospital)
- Unstable
- Presence of multilobar disease or pneumatocele
What is the recommended duration of management in the following scenarios?:
- Outpatient
- Hospitalized
- Empyema
Stable:
- Outpatient: Amoxicillin 40-90mg/kg/day divided TID x 5 days
- Hospital: Ampicillin 200mg/kg/day divided q6h x 7-10 days
Unstable: 3rd gen cephalosporin (Ceftriaxone or Cefotaxime) better H influenzae coverage and high-level PCN-resistant pneumococcus
Multilobar disease/pneumatocele: 3rd gen cephalosporin (Ceftriaxone or Cefotaxime) AND Vancomycin
Empyema = 2-4 weeks
Step-down once afebrile, improving and otherwise ready for hospital discharge.
CXR takes 4-6 weeks to resolve
Describe your management for an uncomplicated pneumonia that is not responding to treatment within 48-72h.
List 3 alternative diagnoses
Management:
What makes a pneumonia complicated?
- 48-72h antibiotics without clinical improvement
- Persistent or worsening respiratory distress and/or hypoxia
- New clinical findings of a pleural effusion
Describe the recommended investigations for an empyema.
CXR
What is the recommended treatment of a complicated pneumonia?
When should you transition to oral antimicrobials? Which one?
- Monitor for clinical improvement (normal for fevers to persist >72h on appropriate therapy, not treatment failure if improving clinically)
- Start Ampicillin or 3rd gen cephalosporin (Ceftriaxone or Cefotaxime) depending on antibiogram
- Add Vancomycin if MRSA suspected
- If moderate-severe respiratory distress → Pleural drainage
- Best evidence for VATS, early thoracotomy or small-bore percutaneous CT placement w/fibrinolytics
- TPA 4mg in 30-50mL NS daily x 3 days
- Best evidence for VATS, early thoracotomy or small-bore percutaneous CT placement w/fibrinolytics
Step down: once clinically improving, drainge completed AND off oxygen
- Cultures negative → Amoxicillin
- MRSA or H influenzae (suspected or proven) → Clavulin
Follow after discharge until clinically recovered and CXR has returned to near normal (can take several months)
- order repeat CXR in 2-3 months for initial assessment
What is the expected prognosis of a complicated pneumonia?
What clinical conditions are potentially responsive to humidified heated high-flow nasal cannula oxygen therapy?
Name 2 contraindications to HHHFNC oxygen therapy
- Obstructive sleep apnea
- Bronchiolitis
- Asthma
- Pneumonia or pneumonitis
- Heart failure (reduces systemic afterload/preload)
CONTRAINDICATIONS
- Nasal obstruction
- Epistaxis
- Severe upper airway obstruction
List 4 complications or considerations for humidified heated high-flow nasal cannula oxygen therapy
- Sudden discontinuation → rapid deterioration in HD and respiratory status
Describe how to start humidified heated high-flow oxygen therapy
- Start 1-2L/kg/min and increase PRN to minimize WOB (max 2L/kg/min - 50-60L/min in adults), wean as WOB improves
- Start FiO2 at 50% and titrate up or down PRN to maintain SpO2 94-98%, wean and transition to low-flow once tolerating lower rate
Name 4 risk factors for inhalant abuse
- Homelessness
- School dropout
- Incarcerated
- Physical, sexual abuse or neglect
- Indigenous
- Additional risk factors:
- Health disparities
- Reduced access to services
- Socioeconomic factors
- Additional risk factors:
- Rural, isolated community
- Reduced community support
- Poor self-esteem
- Suicidality
- Psychiatric conditions, substance abuse
- FMHx substance abuse or peers abusing substances
List 2 short-term complications and 4 long-term complications of inhalant abuse
SHORT-TERM
- Respiratory arrest → CNS depression
- “Sudden sniffing death syndrome”→ disruption of myocardial electrical propogation → arrhythmia
- Death/injuries from dangerous behaviour
- Aspiration or suffocation while “bagging”
- Freezing + burning face and upper aerodigestive tract
LONG-TERM
- Renal tubular acidosis
- Cardiomyopathy
- Hepatitis
- Poor school performance
- Menstrual disorders
- Criminal behaviour
- Spontaneous abortions
- Preeclampsia
- “Fetal solvent syndrome” →microcephaly, cognitive impairments
- Cortical atrophy
- Brainstem dysfunction
- Dyspnea, emphysema-like abnormalities
- Hydrocarbons: Bone marrow toxicity
- Volatile nitrites: Immune impairment (replication of HIV, Kaposi’s sarcoma)
When screening for abuse with the CRAFFT screening tool, what factors are being assessed?
Car driven by someone “high” or had used drugs → been in one?
Relax → do you use alcohol or drugs to relax, feel better about yourself or fit in?
Alone → using alcohol or drugs by yourself
Forget → do you ever forget things you did while using alcohol or drugs
Friends or Family → do they tell you to cut down on your use
Trouble → have you gotten into trouble with use
≥2 indicates potential for substance abuse problem
You discover your patient has been abusing inhalants when completing your history in the ED. How will you manage them?
- Monitor for hypotension
- Complete neurological examination
- Avoid sympathomimetics
- Assess liver, kidney and heart for damage
- Antiarrhythmics or beta-blockers to stabilize myocardium
What intervention is effective with reducing alcohol, marijuana and tobacco use but is NOT HELPFUL for inhalant abuse?
Office-based brief interventions (5-10 min session)
Best Prevention of Inhalant abuse
- Reduce social acceptability
- Evidence-based in-school primary prevention (before use)
- Reduce social factors, such as social determinants of health
Who is at highest risk of severe disease in bronchiolitis?
What factors are likely to influence admission?
What is a bronchogenic cyst?
- Piece of bronchial tissue separate from the developing airway resulting in an epithelium-lined sac that contains cartilage in the wall
- Usually no connection between the bronchogenic cyst and the normal airway
- Presentation:
- Most remain asymptomatic –> incidental detection later in life
- If there is a connection:
- Can develop recurrent or chronic infections of the cyst
- If peritracheal lesion, it can stridor/ airway narrowing
- Feeding difficulties if compress esophagus
- Evaluation:
- CXR - usually fluid filled, but if communication can have air-fluid level
- Barium esophagram
- CT scan
- Treatment:
- Surgical removal if Sx