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
List the definition and risk factors for apnea
Apnea: cessation of airflow for >10 seconds or 2 breath cycles
- obstructive: cessation >10s despite respiratory efforts
- central: cessation for >10s with no respiratory effort
Risks for OSA
- male
- older age >45
- obesity, including pregnancy
- increased neck circumference (normal is 17.5 in men and 15.5 in women)
- substances (smoking, alcohol, sedative, opioid)
- medications
- any structural abnormality with airway
- increased mallampati score
- family history
Discuss the dosing of inhaled corticosteroids
Low Dose - <12 <=200mcg/day - >12 <=250mcg/day Medium Dose - <12 201-400 mcg/day - >=12 251-500 mcg/day High Dose - <12 >400mcg/day - >=12 >500mcg/day
Discuss proper MDI use
- Shake inhaler well
- Remove cap
- put inhaler into spacer
- Breather out away from spacer
- Bring spacer to mouth and close lips around
- Press top of inhaler
- Breathe in slowly (if not using spacer only press top once starting to breath in)
- remove inhaler from mouth and hold breath for 10 seconds
- wait 1 minute and shake in between
- rinse mouth when finished to reduce risk of oral thrush
Discuss the screening for COPD
Spirometry in patient’s over 40 who currently or previously smoked and have one of the following
- Cough regularly
- Productive cough regularly
- Short of breath with minimal exertion
- Wheeze with exertion or at night
- Frequent colds that persist long
Lung Cancer Screen in 55-74 with 20year smoking history
Discuss the screening for lung cancer
- Annual low dose CT for adults 55-74 with 30 pack year smoking history who currently smoke or quit within last 15 years
Discuss the presentation and management of asthma in the ED
Presentation
- previous ICU, intubation, hospital admission
- triggers
- SOB
- Chest tightness
- wheezing
- increased puffer use
Investigation
- FEV1
- CXR
Managemnt
- supplemental O2 to target >92%
- SABA with 3 back-to-back treatments initially
- mild-mod MDI 4-6 puffs Q20-40min
- severe nebulizer 2.5-5mg Q20min
- SAAC (ipatropium bromide)
- same as SABA
- Epinephrine IM if due to anaphylaxis
- if FEV1 <40% despite treatment then MgSO4 2g IV over 20 minutes
- Decrease inflammation with prednision 50mg, dexamethasone 16mg or hydrocortisone 100-200mg IVDiscuss the disposition for asthma exacerbation
Home - Oxygen sat >90% - no respiratory distress and normal exam for >1hr - >=75% expected FEV1 >2hrs since treatment - discharge with Salbutamol, prednisone 50mg for 4 days and inhaled corticosteroid Admitted to Ward - FEV1 40-75% - Mild to moderate symptoms - Risk factors or near-fatal attack Admit to ICU - FEV1 <40% - PaCO2 <60 - PaCO2 >42 - Altered mental statu
Discuss the modified Dyspnea scale for asthma exacerbation
Level of consciousness
- Severe have altered
Appearance
- Respiratory distress and cyanosis in severe
- some respiratory distress in moderate
Vital Signs
- Mild: tachypnea, normal BP and O2 sat
- Mod: Tachypnea, normal BP, decreased O2 sat
- Severe: severe tachypnea, low BP, very low O2 sat
Physical Exam
- Mild: wheezing with bilateral air entry
- Mod: Talking in 3-4words, indrawing, decreased air entry and wheezing
- Severe: talking in 1 word, paradoxical breathing, may have no wheezing
FEV1
- Mild: 50-70%
- Mod: 25-50%
- Severe: <25%
Discuss the presentation and management of COPD in the ED
Presentation
- SOB
- Exercise intolerance
- chest tightness
- Wheezing
- Increased use of puffer
- Infectious if >=2: increased sputum production, increased sputum purulence, increased dyspnea
Investigation
- CBC, electrolytes, creatinine, BUN
- VBG or ABG (if not responding to therapy)
- increased pCO2, decreased pO2
- CXR
- hyperinflated lungs
Management
- O2 support to target of 88-92 as can be CO2 retainers
- can move to BiPAP
- SABA and SAAC same as asthma
- Systemic steroids
- Antibiotics if infectious causeDiscuss disposition for COPD
Home
- if O2 sat >90% at rest and with exertion
- Salbutamol, Prednisone 50mg for 10-14d and inhaled corticosteroid
Discuss when to switch from BiPAP to intubation in COPD
- worsening hypoxemia
- confusion or decreased LOC
- worsening acidosis
- worsening hypercapnia
- pH <7.36 and PaCO2 >45
Discuss the pathophysiology, presentation and management of bronchiectasis
Pathophysiology - irreversible dilatation of airways due to inflammatory destruction of airway walls resulting from persistently infected mucus - Cystic fibrosis, H influenzae, Pseudomonas, M catarrhalis Presentation - Chronic cough with purulent sputum - Dyspnea - Hemoptysis - Inspiratory and exporatory crackles - Wheeze Investigation - PFT obstructive or normal - CXR: linear atelectasis, tram tracking - CT: signet ring with dilated bronchi with thickened walls where diameter bronchus >1.5x diameter of artery Management - vaccination - Chest physio - Abx: inhaled: tobramycin for pseudomonas - Mucolytics
