Respirology - Air Space Disease Flashcards
Discuss the pathophysiology of Asthma
- variable airflow limitation and airway hyperresonsiveness represented by exaggerated contractile response of the airway to variety of stimuli
- atopic march: eczema, food allergies, environmental allergies
- strongest predictor for development
Discuss the symptoms and diagnosis of asthma
Signs and Symptoms
- Wheezing
- Cough
- Dyspnea
- Reduce air entry on auscultation
Diagnosis
- obstrutive pattern on spirometry
- Children 6-11 have FEV1/FVC <0.8 and increased FEV1 post-bronchodilator >=12%
- Adults have FEV1/FVC <0.75 and increase in FEV1 post-bronchodilator by >=12% and >=200mL
- scooped flow volume curve
- high residual volume RV/TLC >0.35
- methacholine challenge where have >20% drop in FEV1 with <4mg/mL of methacholine
- FEV1 drop of >10% at 80% of maximum HR
Discuss possible triggers for asthma exacerbation
- Allergens exposure
- Respiratory infection
- Cigarettes
- Animal dander
- Dust mites
- cold/dry air
- exercise or emotional factors
- B Blockers/ASA/NSAIDs
Discuss the management of asthma
- Environmental control
- Education
- Action plan
Medication - Short-Acting Bronchodilator on demand for very mild
- Inhaled Corticosteroid for maintenance therapy for mild asthma (symptoms 3x per week)
- leukotriene receptor antagonist second line
- start at low dose and progress - Long acting bronchodilator used as third line add on
- must be on ICS if using LABA
- if less than 12 then increase ICS before - Third line to add LTRA
- Fourth line prednisone
Discuss the characteristics of good asthma control
- Daytime Symptoms <4x/week
- Nighttime symptoms <1x/week
- Normal physical activity
- Infrequent and mild exacerbation
- No absences due to asthma
- Need for SABA <4dose/week
- FEV1 >=90% best
- sputum eosinophils <2-3%
Discuss the pathophysiology and symptoms of COPD
Pathophysiology
- airflow limitation caused by inflammatory response to inhaled toxins
Signs and Symptoms
- Productive cough
- Dyspnea
- Decreased breath sounds
- Wheezes
- Prolonged expiratory phase of breathing
Investigations
- PFT: FEV1/FVC <0.7 with no improvement with bronchodilator
- Spirometry increased FRC, RV and decreased VT
- CXR: hyperinflation of lung with flattended diaphragm
Discuss the Triggers and Signs of COPD exacerbation
Triggers - Respiratory infection - Environmental pollution - pulmonary embolism - comorbid respiratory or cardiac condition Signs - Change in amount or color/purulence of sputum - More short of breath - change in mood - Fatigue
Discuss the MRC dyspnea scale of symptoms and impairement of lung function
Normal
- MRC 1 dyspnea only with strenuous exercise
- Normal spirometry
Mild
- MRC 2 dyspnea when hurring on level ground or walking up hill
- FEV1 >80% predicted and FEV1/FVC <0.7
Moderate
- MRC 3 walk slower than people because of breathlessness or has to stop for breath
- MRC 4 stop for breath after walking 100m
- 50% <= FEV1 < 80% predicted
- FEV1/FVC <0.7
Severe
- MRC 5 too breathless to leave house or breathless with dressing
- 30%
Discuss the management of COPD
Education - inhaler - action plan Smoking Cessation - most important intervention to slow lung decline Exercise or Pulmonary Rehabilitation - All patients should exercise Vaccination - influenza - Pneumovax <65 or Prevnar >65 Pharmcotherapy - Mild: SABA prn - Moderate: SABA and LABA/LAAC prn - Severe (>1 AECOPD/year): Long acting anticholinergic + ICS/LABA + SABA prn Oxygen - severe hypoxemia (PaO2 <55mmHg or SaO2 <88%) - PaO2 <59mmHg or SpO2 <89% with evidence of right heart failure or cor pulmonale or erytrhocytosis (Hct >55%) Surgery - lung volume reduction surgery Lung Transplant - FEV1 <25% - PaCO2 >55 - pulmonary hypertension
Discuss the indications for hospitalization for AECOPD
Hospitalized if any of the following
- inadequate response to outpatient emergency department management
- marked increase in dyspnea
- severe underlying COPD, FEV1 <50%
- inability to eat or sleep
- new cyanosis or worsening hypoxemia
- Acute respiratory acidosis
- Change in mental status
- Insufficient home support
- High risk comorbidities
Discuss the in-hospital management of AECOPD
Treatment
- target O2 >90%
- albuterol 2.5mg by nebulizer Q1-4H or 4-8 puffs with spacer
- Ipratropium 500mcg nebulizer Q4H or 2-4 puffs
- systemic steroids (prednisone 40mg PO for 5 days)
Non-Invasive Positive Pressure Ventilation
- respiratory distress: tachypnea >25 RR or use of accessory muscles
- respiratory acidosis: pH <7.35 or PaCo2 >45
Antibiotics
- uncomplicated (<65yo, FEV1 >50%, <3 exacerbations a year, no cardiac disease)
- Azithromycin 500mg POx1d then 250mg Q24H for 4d
- Cefuroxime 500mg PO Q12H
- Doxycycline 100mg PO Q12H x1d then 100mg Q24H
- Septra 1 tab PO Q12H
- Complicated (any of above risk factors)
- Levofloxacin 750mg Q24H
- Amox-Clav 875mg Q12H x1d then 100mg Q24H
- Pseudomonas then Cirpofloxacin
- Abx for 5d if mild-mod, 7d for severe
List the Common Asthma/COPD Inhalers and their side Effects
SABA (blue) - Salbutamol (ventolin) - tachycardia - arrhythmia - irritability - difficulty sleeping - muscle cramps LABA (orange) - formoterol (oxeze) - salmeterol (serevent) - same as SABA ICS (red) - Fluticasone (flovent) - Beclomethasone (ovar) - hoarseness - sore throat - thrust ICS + LABA - Fluticasone + Salmeterol (Advair - purple) - Pulmicort + Oxeze (Symbicort - red) - shaky hands - tachycardia - thrush - sore throat - hoarse Short-Acting Anticholinergic - Ipratropium bromide (atrovent) - dry mouth - urinary retention Long-Activing Anticholinergic - Tiotropium (spiriva) - same as SAAC
Discuss the presentation and consequences of OSA
Symptoms - snoring, apnea, choking - morning headache - GERD - poor quality of sleep resulting in daytime sleepiness, impaired memory/concentration and depression Long-term - systemic hypertension - increased risk of stroke or MI - increased risk of AF or CHF - increased risk of pulmonary hypertension as have vasopasm of pulmonary arteries from decreased desats - increased risk of diabetes - increased risk of depression - daytime hypercapnia and hypoxemia
Discuss the management of OSA
Indications - symptomatic - AHD >=15 as incrase cardiovascular risk - occupation - presence of comorbid condition Non-Specific - weight loss - avoid substances - positional therapy (side sleeping) - avoid sleep deprivation Nasal continuous Positive Airway Pressure (CPAP) - 1st line - continuous blowing of room air into airway splinting it open - BiPAP for larger adults requiring greater pressure Surgery - for underlying anatomical problem
Discuss the diagnosis of OSA
Must have A or B and C
A: Excessive daytime sleepiness that cannot be explained
B: >=2
- recurrent choking or gasping in sleep
- recurrent awakening from sleep
- daytime fatigue
C: Apnea hypopnea index (apnea + hypopnea/hrs asleep) >5 (mild:6-15/hr, mod:16-30/hr, sev: .30/hr)
- hypopnea is decreased airflow by 50% with decreased O2 sat by >4% or EEG arousal