Chapter 3: Respiratory Flashcards
Chronic asthma symptoms?
- coughing, especially at night
- SOB
- chest tightness
- wheezing
(mucous lining in airways)
What is used in all stages of asthma to relieve symptoms?
SABA = salbutamol, terbutaline
Alteratives:
- ipratropium bromide (SAMA)
- if 12+yrs; theophylline or oral b2 agonist (bambuterol)
When should you step up treatment from SABA?
STEP UP IF:
- using inhaler or symptomatic at least 3 times a week
- night time symptoms at least once a week
- asthma attack requiring systemic steroids in last 2 years
- refer if using >1 inhaler a month: not well-controlled
What is step 1 in stepping up asthma treatment?
REGULAR PREVENTERS:
- low dose inhaled corticosteroids –> start BD then reduce to OD if good control
- mometasone, fluticasone, beclometasone, budenoside, ciclesonide
(Qvar, Clenil, Pulmicort, etc)
ALT:
- leukotriene receptor antagonist (montelukast)
- theophylline
- inhaled sodium cromogilate or inhaled nedocromil
What is step 2 in stepping up asthma treatment?
ADD LABA (WITH ICS): - In a combination inhaler with low-dose ics: formoterol, salmeterol
(fostair, symbicort etc)
What is step 3 in stepping up asthma treatment?
STEP 3 PART 1:
No response: STOP LABA –> increase ICS dose
STEP 3 PART 2:
if benefit but control still inadequate: continue LABA –> increase to medium dose ICS
STEP 3 PART 3 if benefit but control still inadequate: continue LABA --> trial LTRA, LAMA (aclidinium (Genuair) glycopyrronium (Breezhaler) tiotropium (HandiHaler, Respimat) umeclidinium (Ellipta)) or SR theophylline
What is step 4 in stepping up asthma treatment?
ADD FOURTH DRUG + HIGH DOSE ICS
- sr theophylline
- LAMA (tiotropium bromide)
- LTRA (montelukast, zafirlukast)
- oral b2 agonist tablet (bambuterol)
What is step 5 in stepping up asthma treatment ?
ADD ORAL PREDNISOLONE
- single dose in the morning to prevent insomnia
- gradually withdraw when stepping down
Selective b2 agonists MOA?
- causes bronchodilation of the bronchi
Inhaled SABA dose and duration?
- 3-5 hours
- sabutamol (QDS PRN) see GP if fails to provide relief
- terbutaline (QDS PRN)
Inhaled LABA dose and duration?
- 12 hours
- formoterol BD
- salmeterol BD
OTHER LABAs
- olodaterol (in adults - COPD)
- indacaterol (in adults - COPD)
- vilanterol (with umeclidinium - COPD/ with fluticasone - asthma)
LABAs - who uses them?
- for patients regularly using ICS
- do not initiate in rapidly deteriorating asthma
Salmeterol
= long onset + long action
not for acute relief or prevention of exercise-induceda asthma
Formoterol
= short onset + long action
- can be used as relievers in addition to regular use as preventer
- review if using more than once a day
(fostair, duoresp, spiromax and symbicort (18+))
LABAs side effects?
- hand tremors, tachycardia, hyperglycaemia
- hypokalaemia (potentiated with concomitant corticosteroids, other b2 agonists and theophylline and hypoxia in severe asthma -> monitor serum K+)
- serious cardiovascular effects (prolonged QT interval, arrhythmias, tachycardia, arterial hypoxia causing MI and hypotension. Take caution in hyperthyroidism)
*explicitly state dose, frequency and max puffs in 24 hours
ICS MOA?
reduces inflammation in the bronchi
Twice daily dosing ICS?
- beclometasone
- budesonide
- fluticasone
- mometasone (can be taken BD/OD)
Once daily dosing ICS?
- ciclesonide
ICS use?
- must take regularly for 3-4 weeks for the prevention of asthma
Beclometasone CFC free inhalers brands?
- prescribe by brand name: Qvar and Clenin modulite CFC free inhalers are not interchangeable
- Qvar is twice as potent as clenil and more potent that CFC containing beclometasone inhalers; Qvar has extra fine particles
- Fostair (beclometasone/formoterol) has extra fine particles and is more potent than traditional CFC free inhalers i.e. inhalers ie Qvar and clenil
Easyhaler 18+, Qvar 12+, Clenil 200/500
What is more potent, Qvar or clenil?
Qvar twice as potent as clenil
ICS side effects?
- hoarse voice
- sore throat
- oral candidiasis (rinse mouth and brush teeth after use or use a spacer) –> daktarin gel treatment (not with warfarin)
- paradoxical bronchospasm (stop and give alternative)
- mild bronchospasm: use SABA before or transfer from pMDI to dry powder inhaler
NICE: use a large volume spacer for…?
- high dose ICS
- patients under 15
Smoking and ICS dose?
Current and previous smoking reduces effectiveness of ICS; the patient may need a higher dose
Leukotriene receptor antagonists MOA?
Blocks action of leukotriene on the cysteinyl leukotiene receptor in the lungs and bronchi; reduces bronchoconstriction and inflammation
LTRAs?
- Montelukast
- Zafirlukast
*chronic asthma and symptomatic relief of hayfever in asthma
LTRA side effects?
- Churg strauss syndrome (blood vessel inflammation)
occurs on withdrawal or reduction of oral corticosteroid. stay alert to eosinophilia (a higher than normal level of eosinophils. Eosinophils are a type of disease-fighting white blood cell), vasculitic rash, worsening pulmonary symptoms, cardiac complications and peripheral neuropathy - Liver toxicity (zafirlukast)
report signs of liver toxicity e.g. nausea, vomiting, jaundice, abdominal pain, itching etc
Theophylline drug class?
Xanthine bronchodilator
What is aminophylline?
Mixture of theophylline/ethylenediamine, given IV, 20x more soluble and too irritant to give IM
What is the therapeutic level of theophylline?
- 10-20mg/L
- NARROW THERAPEUTIC DRUG
- Sample 4-6 hours after dose
PRESCRIBE BY BRAND - NOT BIOEQUIVALENT
What increases theophylline plasma concentration?
- heart failure
- hepatic impairment
- viral infections
- elderly
- enzyme inhibitor
What decreases the plasma concentration of theophylline?
- smokers
- alcohol
- enzyme inducers
Signs of theophylline toxicity?
“FAST AND SICK”
- vomiting and GI effects initially (diarrhoea, gastric irritation)
- tachycardia, CNS stimulation (restlessness, agitation, dilated pupils)
- arrhythmias, convulsions and hypokalaemia are more serious effects
What drugs cause increased risk of hypokalaemia when given with theophylline?
= loop/thiazide diuretcis, corticosteroids, b2 agonists
What drugs cause an increased risk of convulsions when given with theophylline?
= ciprofloxacin. Pk and Pd interaction: quinolones are enzyme inhibitors and they lower seizure threshold; theophylline side effect is convulsions
What drugs cause an increased plasma concentration and risk of toxicity when given with theophylline?
= verapamil/CCB, cimetidine, phenytoin, fluconazole, macrolides are enzyme inhibitors
What drugs cause a reduced plasma concentration with theophylline (subtherapeutic dose)?
= st johns wort, rifampicin
enzyme infucers
What is acute asthma?
MEDICAL EMERGENCY
- regard all cases of asthma attacks as severe
- failure to respond requires transfer to hospital
How should acute asthma be managed?
- moderate acute asthma can be treated at home/primary care
- severe or life threatening acute asthma = hospital stat
- supplementary o2 should be given to all hypoxaemic patients to maintain SpO2 level 94-98%
- FIRST LINE = high dose inhaled SABA or continuous nebuliser 2-10 puffs every 10-20 mins or prn/ neb every 20-30min
- In ALL cases of acute asthma: oral prednisolone, continue ICS or IV hydrocortisone alternative
- child under 12 = up to 3 days
- adult: at least 5 days (40=50mg OD)
- high flow o2 given if available
What is COPD
CHRONIC OBSTRUCTIVE PULMONARY DISEASE
Irreversible airway obstruction
What is initial therapy in COPD for breathlessness or exercise limitation?
SABA OR SAMA (stop if LAMA started)
What is the step up treatment for COPD patients WITHOUT asthmatic features or features suggesting steroid responsiveness?
Offer LABA and LAMA. (discontinue SAMA if LAMA given). Treatment with SABA may be required at all stages of COPD
What is offered as the step up to patients on LAMA and LABA who have a severe exacerbation or at least 2 moderare exacerbations requiring systemic ccsteroids/antibiotics within a year?
Consider ICS triple therapy
What is considered in patients on LAMA and LABA whose day to day symptoms impact QOL?
Trial ICS for 3 months, if symptoms have improved, continue triple therapy and review at least annually. If there has been no improvement, step back down to a LAMA and LABA
What is the step up treatment for patients WITH asthmatic features or features suggesting steroid responsiveness?
LABA and ICS
In patients on a LABA and ICS who have a severe exacerbation or 2 moderate exacerbations within a year or who contrinue to have day to day symptoms impacting QOL what is added?
Add LAMA triple therapy (discontinue SAMA if LAMA given)
What prophylactic antibiotics can be used to reduce the risk of exacerbations?
- azithromycin [unlicensed] in non-smokers with all other treatment optimised and who continue to have prolonged or frequent (4 or more a year) exacerbations with sputum production or hospitalisation
- need sputum culture before
- CT scan of thorax to rule out other lung pathologies
- basline ECG to rule out QT prolongation
- LFTs before
- review at 3 months then at least 6 monthly
Other add on treatments for COPD?
- rofluminast in severe COPD with chronic bronchitis (specialist)
- consider mucolytic treatment in patients with chronic cough productive of sputum
- MR theophylline should only be given after trial of SA and LA bronchodilators or if patient unable to use inhaled treatment
What is used in severe COPD with hypoxaemia?
OXYGEN THERAPY
- 15 hours a day or more prolongs survival
- 88-92% o2 saturation (risk of hypercapnic resp failure)
- must carry o2 alert card and use 24 or 28% venturi mask if history of hypercapnic resp failure
What antibiotics are given during an acute exacerbation of COPD?
Oral first line: amoxicillin, clarithromycin or doxycycline
- alternative if at high risk of treatment faiure: co-amoxiclav or levofloxacin
Oral second line: first line antibacterial from another class or co-amox, levoflox, or co-trimazole (only when sensititvities available)
IV first line: amoxiciliin, co-amoxiclav, clarithromycin, co-timoxazole, or piperacillin with tazobactam
IV second line: specialist
Inhaled antimuscarinics MOA?
relaxes smooth muscle of bronchi to cause bronchodilation
LABA inhalers?
- Olodaterol (Striverdi respimat)
- Indaceterol (onbrez breezhaler)
- Vilanterol with umeclidinium (Anoro elipta)
SAMA inhalers?
Ipratropium bromide (TDS)
LAMA inhalers?
Take OD except Elira BD
- Aclidinium (eklira genuair - green/red window and dose indicator)
- Glycopyronnium (Seebri breezhaler)
- Umeclidinium (incruse elipta)
- Tiotropium (Spriva handihaler)
- spiriva respimat licensed as adjunct to LABA/ICS in asthma with 1 or more severe exacerbation in past year
LABA/LAMA combo inhalers also available
Cautions of inhaled anti-muscarinics?
- prostatic hyperplasia
- risk of angle-closure glaucoma: reported with nebulised ipratopium, especially when given with salbutamol. Protect eyes
Inhaled anti-muscarinics side effects?
- dry mouth most common
- paradoxical bronchospasm
COPD exacerbation therapy?
BRONCHODILATOR THERAPY
(via nebuliser with oxygen if needed) e.g. SAMA, SABA, theophylline
IV AMINOPHYLLINE
(if poor response to nebulised bronchodilator)
SHORT COURSE ORAL PREDNISOLONE
30mg daily for 7-14 days if increased breathlessness interferes with daily activities
ANTIBACTERIAL THERAPY
e.g. amoxicillin etc see specific guidelines
Antihistamines MOA?
Binds to H1 receptor site to block the action of histamine
Old sedating antihistamines?
- promethazine (most sedating BD/TDS)
- alimemazine (most sedating)
- chlorphenamine (QDS)
- hydroxyzine (QT prolongation)
- ketotifen (antihistamine NSAID)
- clemastine
- cyproheptadine
New non sedating antihistamines?
= less sedation and psychomotor impairment
- acrivastine (TDS)
- bilastine
- mizolastine
- cetirizine and levocetirizine (OD)
- loratidine and desloratidine (OD)
- fexofenadine (OD)
Antihistamine indications?
MAIN
- allergies: nasal (hayfever), skin (uticaria aka hives)
OTHER USES
- Nausea and vomiting = cinnarizine, cyclizine, promethazine hydrochloride, promethazine teoclate, buclizine (migraines only - OTC)
- Insomnia = promethazine hydrochloride, diphenhydramine (both OTC)
- adjunct in emergeny anaphylaxis and angioedema - chlorphenamine/promethazine injection
Antihistamine side effects?
- OLD = more sedating + antimuscarinic
- NEW = less sedating + less psychomotor impairment (connection between mental and muscle)
Avoid alcohol, driving may be impaired
Important antihistamine cautions?
- benign prostatic hyperplasia (urinary retention)
- glaucoma (raised intraocular pressure)
- severe liver impairment (sedation precipitates hepatic coma)
Unique antihistamine with MHRA warning?
Hydroxyzine
MHRA warning: QT prolongation and torsade de pointes
USE: short period only. Max adult daily dose 100mg
Hydroxyzine c/i?
(risk factor for QT prolongation)
- concomitant drugs that prolong QT interval
- CVD
- family history of sudden death
- hypokalaemia
- hypomagnesaemia
- bradycardia
What is allergen immunotherapy?
Using allergen vaccines containing house dust mite, animal dander or extracts of grass or tree pollen to reduce allergic asthma symptoms and allergic rhinoconjunctivitis
Also to reduce severe anaphylaxis in hypersensitivity to wasp and bee stings (allergen vaccines containing wasp and bee venom extract)
Allergen immunitherapy saftey concerns?
Hypersensivity reaction = life threatening and bronchospasm and anaphylaxis
- specialist use and monitor for at least 1 hour
- have CPR immediatley available
AVOID IN:
- asthma (or extra caution)
- pregnant women
- children under 5
- beta blockers
- ACE inhibs
What is used for allergen immunotherapy?
OMALIZUMAB injection –> monoclonal antibody that binds to IgE
Omalizumab uses ? (add on treatment)
- severe persistent allergic asthma (IgE mediated) 6+ (inadequate response to high dose ICS with LABA, who need frequent oral corticosteroids > 4 courses in last year)
- chronic spontaenous urticaria 12+ (indadequate response to h1 antihistamines, leukotriene receptor antagonists)
Omalizumab side effects?
Churg-strauss syndrome (associated with reduction of oral corticosteroid and hypersensitivity reactions)
What drug treatment is given in anaphylaxis?
ADRENALINE (1 in 1000 solution)
- IM injection to anterolateral aspect of mid thigh
- repeat every 5 mins if necessary
- child under 6: 150mcg
- child 6-12 yrs: 300mcg
- adult/child 12-18: 500mcg (300mcg if child small/pre-pubertal)
Given IV if compromised ciculation
*patients treated with beta blockers may not respond to adrenaline - consider bronchodilator e.g. IV salbutamol
Adjuncts to adrenaline in anaphylaxis ?
- high flow oxygen and IV fluids
- chlorphenamine injection (counter histamine-mediated vasodilation and bronchoconstriction)
- hydrocortisone injection (prevents further deterioration in severely affected patients
Self administration adrenaline?
Jext, Epipen, Emerade (adrenaline auto-injectors)
- adult 300/500mcg
- child 15-30kg 150mcg
- carry 2 auto-injectors at all times
- midpoint of outer thigh
- second injection 5-15 mins after first
- call ambulance even if symptoms improve
- lie down and raise legs or sit up if breathing difficulties
- check expiry dates
What is angioedema?
- Sweling of the skin often caused by allergic reactions.
- in severe cases laryngeal oedema is present which is dangerous; treat as for anaphylaxis
- adrenaline and o2
- antihistamine
- corticosteroid
Mucolytics MOA?
- facilitates expectoration by reducing sputum viscosity
CARBOCISTEINE
ERDOSTEINE
Mucolytics use?
- reduces COPD exacerbations in patients with a chronic productive cough
Mucolytics c/i’s ?
- active peptic ulcers (mucolytics disrupt gastric mucosa)
What is croup?
Croup refers to an infection of the upper airway, which obstructs breathing and causes a characteristic barking cough. The cough and other signs and symptoms of croup are the result of swelling around the voice box (larynx), windpipe (trachea) and bronchial tubes (bronchi).
MEDICAL EMERGENCY
Treated with dexamethasone or prednisolone oral solution : child 1 month to 2 years
In severe cases nebulised adrenaline/epinephrine
