Respiratory Flashcards
What is asthma?
What are the 3 factors that contribute to airway narrowing?
A chronic inflammatory disorder of lung airways, characterised by airway hyperresponsiveness leading to bronchospasm and reversible airway obstruction.
-Reversible airway narrowing
- Bronchial muscle contraction (spasm) –> hypersensitive airways react to variety of stimuli e.g exercise, cold air
- Inflammation of mucous membranes
- Increased mucous production and secretions
What are the main two types of asthma?
- Eosionophilic –> atopy/allergic asthma. Type 1 hypersensitivity. Associated w genetic tendency of immune system to produce IgE in response to common environmental allergens e.g pets, pollens
- Non-eosinophilic —> Not associated w allergy. Thought to involve more local immune response, involves neutrophil recruitment in airways.
What are the RF for asthma?
- FH or PMH of hayfever, eczema, food allergies, drug allergies. Exposure to dust, fumes, allergens such as occupational dust (type 3 hypersensitivity) or pets.
- Provoking features –> allergens, infections, menstrual cycle, cold air, emotion
- Onset in childhood common,
- 20s-70s onset w no allergies –> late onset non atopic
What is the typical presentation of asthma?
- Intermittent SOB
- Dry cough –> worse at night and in morning –> Diurnal
- Episodic wheeze
- Morning chest tightness
- Diurnal variation of symptoms, worse 3-5 morning
- Precipitant e.g exercise
-In children –> cough wheezing, may describe tight chest as tummy ache. Ask about premature birth, low birth weight, previous bronchiolitis or croup
What are the 1st line and gold standard investigations for asthma?
GOLD STANDARD –> exhaled nitric oxide. Fraction of exhaled nitric oxide >40ppb +ve for asthma. Leverl in breath, produced to fight inflamm –> muscle relaxant. Normal <25 adults, <20 children.
1st line –> Spirometry w reversibility. FEV1/FVC ratio <70% adults <85% children. Reversibility testing –> asthma suggested by larger >400ml response to bronchodilators or prednisolone. FEV1 increase 12% and increase 200ml volume.
Alternative when spirometry not available –> peak flow –> PEFR reduced in asthma. Peak flow meter and diary 2-4 weeks aid diagnosis. 20% diurnal variation >3 days a week for two weeks –> typical asthma. Compare to expected values e.g age, gender, height.
-Children <5 can’t perform spirometry –> clinical diagnosis, trial treatment e.g low dose ICS,
What is the management for asthma in adults?
What are the features that mean asthma is not being controlled?
Aim –> No daytime symptoms, no night time waking, no need for resuce medicaiton, no limitations ADL, no attacks.
Step wise –> Move up and down as needed
1 –> SABA as required for symptom relief. More than OD or night time symptoms –> step 2. Most patients start step 2.
2 –> Add low dose ICS. Beclomethasone, budesomide.
3 –> Add LTRA. Montelukast. Check patients adherence and inhaler technique.
4 –> Add LABA. Salmeterol. W or w/o LTRA depends whether effective.
5 –> Low dose ICS w LABA in MART regimen. Symbicort.
6 –> Increase ICS to moderate.
7 –> Increase ICS to high. Refer to specialist.
MART –> Maintenance and reliever therapy. Combined ICS and LABA in one inhaler.
-Severe eosinophilic –> biologic therapies. Anti IgE –> omalizumab –> removes IgE allergy Ab. £30,000 per year.
What is the management for asthma in over 5’s - 16s?
1 --> SABA 2 --> Low dose ICS and LTRA 3 --> Stop LTRA, add LABA 4 --> MART 5 --> Moderate dose ICS 6 --> High dose ICS specialist
What is the management for asthma in under 5’s?
1 --> SABA 2 --> Low dose ICS 3 --> Moderate dose ICS 4 --> Add LTRA 5 --> Stop LTRA, specialist
What is a severe asthma attack and how should it be managed?
Severe Any one of
- PEFR 33-50% predicted
- RR >25
- Hr >110
- Inability to complete sentences
What are the differences in presentation COPD v asthma?
- COPD rarely <35s, asthma commonly children
- COPD 85% history smoking. Asthma varies.
- Both w cough, COPD productive and sputum. Asthma nocturnal.
- Both SOB, COPD persistent, asthma intermittent.
- Night time waking in asthma not COPD.
- Asthma diurnal and day to day variation. COPD continual and progressive symptoms.
- Spirometry w reversibility –> asthma yes, COPD no.
What is COPD?
- Progressive airway obstruction w little or no reversibility. Characterised by infiltration of neutrophils.
- Encompasses chronic bronchitis and emphysema.
Bronchitis
- Hypertrophy and hyperplasia of mucous secreting glands, inflamm of bronchial tubules, airway narrowing and subsequent obstruction.
- Chronic bronchitis –> productive couhg >3 months in two consecutive years, can produce large amounts sputum.
Emphysema
-Destruction of lung parenchyma w dilation f alveolar airspaces w loss of elastic recoil and air trapping.
-Patients w COPD divide into those w predominant breathlessness (emphysema) or predominant exacerbations (chronic bronchitis).
What are the risk factors for COPD?
- Age >35, middle age
- Smoking of history of smoking 85%
- Occupation exposure e.g dust
- FH alpha 1 antitrypsin deficiency –> younger patients
- Provoking factors infections and cold air
What is the typical presentation of COPD?
What is the presentation of an acute excerbation?
-Acute exacerbation –> worsening previously stable COPD, beyond day to day variation. Mya be due to viral or bacterial infection. Increase SOB, sputum volume and purulence.
- History of several months of progressive worsening of symptoms –> exertional SOB, chronic cough and sputum
- SOB, chronic cough, regular sputum production, frequent winter bronchitis, wheeze.
- Tachypnoea, use accessory muscles, may be cyanosis.
- May be weightloss –> hard to breath when eat
What are the 1st line and gold standard investigations for COPD?
1st line and GOLD standard –> spirometry w reversibility testing.
- Airway obstruction defined as <80% predicted and a reduced FEV1/FVC ratio <0.7/70%.
- Reversibility –> spirometry before and after dose of inhaled bronchodilator.
- Clinically significant not present when FEV1 and FEV1/FVC ratio return to normal.
- CXR –> may show hyperinflation
- ECG –> r/o features cardiac disease e.g HF
What is ACCOS?
- Think when patients also have features of asthma, treat those w ACCOS as those w recurrent exacebations.
- Common variable airflow obstruction but not completely reversible
What is the staging for COPD?
Stage by FEV1
- Stage 1 –> mild >80%
- Stage 2 –> moderate –> 50-79%
- Stage 3 –> Severe –> 30-49%
- Stage 4 –> <30%
What is the MRC dyspnoea scale?
Measures impact of SOB on patient
1 –> SOB on exertion
2 –> SOB up hills or walking quickly
3 –> Walks slower or stop on flat as SOB
4 –> Exercise tolerance 100-200 yards on flat
5 –> Housebound, SOB on minor tasks
What is the medical management for COPD?
Step 1 –> breathless and exercise limitation –> SABA PRN. Continue at all steps.
Step 2 –> Still symptomatic, combination inhaler
- Predominant breathlessness (emphysema) –> LABA (salmeterol) AND LAMA (tiotropium)
- Two or more exacerbations in last 12 months of previous history of confirmed asthma –> ICS and LABA
Step 3 –> Ongoing excaberations (2 or more in 6 months) or admission to hospital.
-Triple therapy –> ICS and LABA and LAMA.
Step 4
-Still symptomatic –> consider theophylline
What are the other interventions in COPD?
- Smoking cessation advice –> only disease modifying treatment that slows FEV/FVC decline.
- Pulmonary rehabilitation
- Exercise –> exercise training programme –> increases tolerance and improves SOB
- Vaccinations –> flu and pneumococcal
- Mucolytics in those w heavy mucous production
- Long term oxygen therapy in severe COPD causing hypoxia and cyanosis.
- Antidepressants when needed
How should exacerbations of COPD be treated?
What should be done when there is no improvement in symptoms?
- Increase dose of SABA
- Exacerbation and sputum purulence –> Ab 1st line doxycycline. Alternative amoxicillin. PA clarithromycin.
- Oral corticosteroid –> prednisolone 30mg OD 1-2 weeks.
No improvement in symptoms on first choice for 2-3 days
- Send a sputum sample for culture and susceptibility testing.
- Offer an alternative first choice antibiotic from different class (guided by susceptibilities when available).
If the person is at higher risk of treatment failure e.g frequent antibiotic use, previous or current sputum culture with resistant bacteria or high risk of developing complications)
-Consider prescribing co-amoxiclav 500/125 mg TDS 5 days
What is sleep apnoea?
What are the RF?
- Intermittent closure/collapse of the pharyngeal air way causing apnoeic episodes during sleep. These are terminated by partial arousal.
- Upper airway obstruction –> episodes apnoea >10 seconds without breathing, usually hundreds in night. –Causes frequent waking, giving sawtooth pattern sleep.
- 90% due to pharyngeal obstruction from large neck particularly >40cm circumference.
- Common in obesity.
- Others due to retrognathia (setback mandible) or enlarged tonsils in children.
- 1 in 4 when BMI >30
- RF –> obesity, age, male, alcohol, smoking, hypothyroidism
What is the typical history and presentation of sleep apneoa?
- Loud snoring. Snoring gasping and choking during sleep.
- Daytime somnolence.
- Poor sleep quality.
- Morning headache.
- Decreased libido.
- Nocturia.
- Decrease cognitive performance.
- Increase risk HTN
What are the investigations for sleep apnoea?
What is the diagnostic test?
- Simple studies –> pulse oximetry and video recordings can be all that’s needed to diagnose
- Epworth sleepiness scale –> initial screen >10 –> referral sleep service
- Neck circumference and BMI. Check nasal patency, tongue size, oropharynx for large tonsils or other obstructions.
- BP and glucose
- DIAGNOSTIC TEST –> Polysomonography –> which monitors oxygen saturation, airflow at the nose and mouth, ECG, EMG chest, and abdominal wall movement during sleep. Can be attended or non attended. Apnoea-hypopnea index and scores, >5 mild, >15 moderate, >30 severe. The occurrence of 15 or more episodes of apnoea or hypopnoea during 1h of sleep, on average, indicates significant sleep apnoea.
What is the management for sleep apnoea?
- Lifestyle –> lose weight, avoidance of tobacco and alcohol.
- Sleep hygiene –> avoid sedatives in evening including alcohol and advise sleeping on side.
- Inform DVLA when OSA and symptomatic w day time sleepiness. Can drive as long as treatment effective.
- 1st line for symptomatic OSA effective QOL –> Nocturnal continuous positive airway pressure CPAP –> CPAP via a nasal mask during sleep is effective and recommended by NICE for those with moderate to severe disease. Often lifelong.
- Surgery to relieve pharyngeal or nasal obstruction, eg tonsillectomy or polypectomy, is occasionally needed.
What is acute bronchitis?
What are the RF?
- Short term inflamm of bronchi
- > 90% cause is viral –> RSV, rhinovirus, influenza. After cough, sore throat or flu.
- Small % –> mycoplasma pneumonia and Bordetella pertussis
- Irritation of airways –> damage –> inflamm, neutrophils infiltrating lung tissue. Mucosal hypersecretion promoted by substance released by neutrophil.
-RF –> smoking, dust, air pollution
What is the typical presentation of acute bronchitis?
What is the differential diagnosis?
Expectorating cough, SOB, wheeze, chest discomfort, fever, fatigue, malaise.
-Symptoms peak after 2-3 days then clear. Commonly takes 2-3 weeks for cough to go completely.
DD –> pneumonia, bronchiolitis, bronchiectasis, COPD, asthma
What are the investigations for acute bronchitis?
-Often clinical diagnosis
- Bloods –> FBC, CRP
- Sputum sample showing neutrophil granulocytes (inflammatory WBCs) and culture showing pathogenic microorganisms.
- CXR when possible pneumonia
What is the management for acute bronchitis?
When should antibiotics be given?
- Most cases self-limited and resolve in few weeks
- Fluid intake and analgesia –> Paracetamol and NSAIDS to reduce fever
- Stop smoking
- Self-care –> honey, OTC cough medicine
- AB not generally used as don’t make large difference to duration symptoms, shorten couhg by ½ day on average. Adverse effects e.g diarrhoea.
- Offer Ab when systemically unwell. And offer back up Ab when higher risk complications e.g pre-existing comorbid condition, >65 w 2 or >80 w 1 –> diabetes/CHF/hospital admission <1 year, using oral corticosteroids.
- Ab –> 1st line –> amoxicillin 500mg TDS 5 days. Alternative –> clarithromycin.
-Refer hospital when acute cough and S+S of more serious e.g PE
What is pneumonia and the types e.g CAP?
- Inflamm of the lung parenchyma usually due to bacterial infection.
- CAP –> community acquired pneumonia. Strep. pneumonia, g+ve cocci —> 31% cases,
- HAP –> hospital acquired pneumonia –> develop at least >48 hours after hospital admission. Most commonly g-ve rods –> kleibsella, e coli, pseudomonas. Also staph aureus –> g+ve cocci –> more likely cause severe.
- Aspiration –> mixed aerobic and anaerobic bacteria.
- Immunosuppression pneumonia –> e.g HIV –> broad range organisms. Important to spot. Not normal CURB65.
- Legionelle pneumonia –> associated w foreign trabel to less economically developed countries and use of air conditioning units.
- Chronic pneumonia –> Not only infectious, also cancer.
What are HIV pneumonias?
-Opportunistic pneumonias that occur as a result of immunodeficiency
-Vary across a broad spectrum from bacterial/mycobacterial and viral to fungal and parasitic.
Major cause mortality.
-CD4 count can potentially evaluate which organism is most likely causative agent
-Strep p, haemophilus influenza, pseudomonas, mycobacterium tuberculosis, pneumocystis jirovecii (p carini)
-Pneumocysitis pneumonia –> AIDS defining condition.
What are fungal pneumonias?
What are the RF?
How should they be treated?
- Fungal infections commonly affect lungs either directly be affecting lung tissue or throuhg their ability to elicit immunological reaction when fungal material is inhaled.
- In immunocompromised –> funal penumoia can disseminate haematogenously resulting in systemic mycoses
- Usually due to opportunisitic infections
- Common –> mucos spp/aspergillus (mold), candida spp/cryptococcus (yeast), histoplasma spp/blastomyces spp/coccidioides.
RF
- Immunocompromised
- Exposure bat/bird droppings
- Travel to endemic countries –> South America
- Fungus categorised into –> mold, yeast, dimorphic fungus
- -Specific fungal serology tests
- If immunocompromised address cause
- Azole based anti fungals e.g voriconazole.
What is the pathophysiology of bacterial pneumonia?
Bacteria over come bodies defences to infect alveoli, Bacteria from URT translocate –> sterile distal airway –> macrophage eat bacteria phagolysosome inside get overwhelmed –> overwhelm host defence –> inflamm response –> cytokines –> neutrophils and some bacteria die –> pus in alveoli.
What is the pathophysiology of viral pneumonia?
Virus invades pneumocytes (cells of lung), virus reproduces. Some cells can directly causes pneumocyte death. Bodys inflammatory response further damages tissues w onflux of inflamm cells causing fluid to infiltrate alveroli, impairng oxygenation fo blood.
RF –> Most common in extreme of age.
What is the presentation of pneumonia?
What do you find on examination?
GENERAL
- Productive cough –> inflamm in lower lung feels like irritation in back of throat.
- Purulent sputum –> May be none. S pnemoniae is rusty. Kleibsella is red jelly.
- SOB
- Pleuritic chest pain –> particularly in s pnemoniae. Lining of lung –> somatic nerve endings, localise pain.
- Signs infection –> fever, sweats, malaise, weakness.
- Confusion –> can be only sign in elderly
-Increase HR, RR, low BP, fever, dehydration.
Viral v bacterial
- Chest pain more common in bacterial
- Viral –> non productive cough, fever and chills, systemic e.g runny nose, myalgia, fatigue, headaches.
EXAMINATION
- Signs lung consolidation –> eprcussion and auscultation –> dull, decrwase air entry, bronchial breath sounds, crackles and wheeze.
- Non resonant percussion –> fluid and pus not air.
- Hypoxia and signs RF in severe or underlying lung disease
What is management pneumonia?
Who gets the vaccine?
CURB 65 0-1 mild –> Amoxicillin 1st line. PA then doxy/clarithro/erthro.
CURB 65 2 moderate –> amxoi and clarith (erythro when pregnant)
CURB 3-5 severe –> Coamoxiclav and clarith/erythro. Can be IV coamoxiclav and clarithromycin.
Complications –> type 1 resp failure, empyema
-Vaccine –> >65s, chronic lung disease, immunosuppression, chronic heart, kidney
Viral
- Most cases self limiting, resolve 1-3 weeks.
- More serious –> respiratory failure.
- Following viral infection –> lung tissue more susceptible to bacterial infection as damage because of virus. (Can get bacterial pneumonia after primary viral infection).
What are the investigations for pneumonia?
DIAGNOSTIC –> CXR –> consolidation (lung infiltrates in viral more likely to be bilateral)
- Sputum –> microscopy and culture
- Nasopharyngeal swabs –> viral culture
- Bloods –> CRP. LFT more likely to be deranged when atypical e.g legionella. Check virus w viral PCR.
- Pulse oximetry.
- ABG, respiratory failure.
- Pleural fluid may be aspirated for culture
How do you assess the severity of CAP?
CURB 65/CRB65
- Confusion, urea >7mmol, RR >30, BP <90/60, >65
- 0-1 or 0 CRB –> mild, only admit to hospital when social circumstances or single worrying feature.
- 2 OR 1,2 CRB–> moderate –> hospital
- 3-5 or 3,4 CRB –> severe –> admit
What is the flu?
- Acute viral infection of lungs and airways
- Spread through droplets
- Influenza –> member orhtomyxoviridae family.
- Three serotypes –> A (severe illness, pandemics), B (mild, only humans), C (minor symptoms, asymptomatic, children)
- Categorised by combination surface antigens.
- Haemogluttinin –> entrance to cells
- Neuramindase (gets virus loose from infected cells)
- Antigenic shirt –> major change
- Antigenic drift —> minor mutations, seasonal
What is the presentation of flu?
- Incubation 1-4 days. Infective from 1 day before to 7 days after symptoms.
- Upper and lower respiratory tract symptoms
- Symptoms 3-5 days. Cough and fatigue 1-2 weeks
- Quick onset
- Cough non productive, coryza
- Fever, rigors, fatigue, anorexia
- Headache, myalgia
- Nausea and vomiting, conjuncitivitis, photophobia
What are the investigations for flu?
- Often clinical diagnosis, ENT and chest examination
- Acute onset, fever and cough –> positive predictive value
- Nasal/throat swabs for PCR confirmation in severe
What is the management for flu?
- Uncomplicated illness –> conservative –> symptomatic treatment –> rest, increase fluid intake, analgiesia e.g paracetamol.
- Complication –> includes LTRI, excerbation of underlying medical condition needing hospital admission.
- Medical –> selective use antiviral inhibitors –> block viral enzyme –> neuraminidase inhibitiors –> oseltamivir. >1 year old and within 48 hours symptoms.
Pneumonia can result from flu directly or more commonly due to secondary bacterial infection.
What is a pulmonary embolism?
What are the RF?
- Occlusion of a pulmonary artery by an embolic thrombus
- Common
- Venous thrombi usually from fragment of detached thrombus from DVT that passes in IVC and embolises through R side of heart through RA and RV, passes into pulmonary arterial circulation and lodges in pulmonary artery –> block blood flow to lungs.
- RF for DVT –> recent surgery or immobility, inherited thrombophilia, long haul flight or car, cancer, pregnancy and OCP, HRT, obesity, other DVT
- Cancer –> activates thrombin
- Oestrogen –> increase fibrinogen and thrombin.
What is the presentation of a PE?
- Depends on size of embolus
- Blockage major pulmonary artery –> death as suddent big increase in pulmonary arterial pressure, acute RV failure, cardiac arrest
- Medium –> v/q mismatch
History any RF for DVT
- SOB
- Pleuritic chest pain
- Haemoptysis
- Syncope
- Cyanosis
-Check calves –> pain, warmth, swelling, erythema, tenderness
What are the investigations for a PE?
- Wells score DVT and PE. DVT score >2 +ve. PE score >4 +ve.
- Wells PE >4 –> CTPA and LMWH.
- DVT >2 or Wells PE <4 –> d dimer –> +ve then CTPA and LMWH. -ve reassess.
- CXR –> r/o other conditions
- Bloods –> d dimer but low specificity
- Imaging when wells or d dimer +ve
GOLD STANDARD –> CTPA –> CT pulmonary angiogram –> visualise major segmental thrombi. Insert dye where holes emboli.
-V/Q perfusion
Others
- ABG –> decrease O2 and CO2, increase pH
- ECG –> 50% sinuse tachycardia
- Unprovoked –> consider thrombophilia screen
- Look for underlying cancer –> bilateral. Suggest by history, exam, bloods.
