Presented by Dr.Amany Abo Zeid at Emergency Medicine Update Course held at Cairo, Egypt. Organized by Scribe www.scribeofegypt.com

1. A M A N Y A B O U Z E I D M D , F R C P , F C C S
P R O F . O F P U L M O N O L O G Y
C A I R O U N I V E R S I T Y
Asthma in the acute care
setting

2. Objectives
 Definition of acute asthma.
 Clinical assessment.
 Level of severity.
 Treatment of acute severe asthma.

3. Definition of asthma exacerbation
 Asthmatic exacerbations are defined as episodes of
increased breathlessness, cough, wheezing, chest
tightness or some combination of these symptoms.
 Exacerbations may have a progressive or abrupt
onset and are always related to decreases in
expiratory (and in severe cases also in inspiratory)
airflows that should be quantified objectively by lung
function measurements(PEF;FEV1).GINA 2013.

4. Epidemiology
 Annual worldwide deaths from asthma have been
estimated at 250,000 people.
 Fatalities appear to have been decreasing worldwide
over the past 15 years, even in the face of an
increasing prevalence of the disease
Drugs 2009; 69 (17): 2363-2391

5. Clinical features Clinical features can identify some patients with severe asthma,
e.g. severe breathlessness, tachypnea, tachycardia, silent chest,
cyanosis, accessory muscle use, altered consciousness or
collapse.
None of these singly or together is specific. Their absence does not
exclude a severe attack.
Initial assessment – the role of symptoms,
signs and measurements
British Guideline on the Management of Asthma revised Jan 2012

6. Clinical features Clinical features can identify some patients with severe asthma,
e.g. severe breathlessness, tachypnea, tachycardia, silent chest,
cyanosis, accessory muscle use, altered consciousness or
collapse.
None of these singly or together is specific. Their absence does not
exclude a severe attack.
PEF or FEV1 Measurements of airway calibre improve recognition of severity and guide
hospital or at home management decisions. PEF is more convenient and
cheaper than FEV1. PEF as % previous best value or % predicted most
useful
Initial assessment – the role of symptoms,
signs and measurements
British Guideline on the Management of Asthma revised Jan 2012

7. Clinical features Clinical features can identify some patients with severe asthma,
e.g. severe breathlessness, tachypnea, tachycardia, silent chest,
cyanosis, accessory muscle use, altered consciousness or
collapse.
None of these singly or together is specific. Their absence does not
exclude a severe attack.
PEF or FEV1 Measurements of airway calibre improve recognition of severity and guide
hospital or at home management decisions. PEF is more convenient and
cheaper than FEV1. PEF as % previous best value or % predicted most
useful
Pulse Oximetry Necessary to determine adequacy of oxygen therapy and need for arterial
blood gas measurement. Aim of oxygen therapy is to maintain SpO2 92%
Initial assessment – the role of symptoms,
signs and measurements
British Guideline on the Management of Asthma revised Jan 2012

8. Clinical features Clinical features can identify some patients with severe asthma,
e.g. severe breathlessness, tachypnea, tachycardia, silent chest,
cyanosis, accessory muscle use, altered consciousness or
collapse.
None of these singly or together is specific. Their absence does not
exclude a severe attack.
PEF or FEV1 Measurements of airway calibre improve recognition of severity and guide
hospital or at home management decisions. PEF is more convenient and
cheaper than FEV1. PEF as % previous best value or % predicted most
useful
Pulse oximetry Necessary to determine adequacy of oxygen therapy and need for arterial
blood gas measurement. Aim of oxygen therapy is to maintain SpO2 92%
Blood gases
(ABG)
Necessary for patients with SpO2 <92% or other features of life threatening
asthma
Initial assessment – the role of symptoms,
signs and measurements
British Guideline on the Management of Asthma revised Jan 2012

9. Clinical features Clinical features can identify some patients with severe asthma,
e.g. severe breathlessness, tachypnea, tachycardia, silent chest,
cyanosis, accessory muscle use, altered consciousness or
collapse.
None of these singly or together is specific. Their absence does not
exclude a severe attack.
PEF or FEV1 Measurements of airway calibre improve recognition of severity and guide
hospital or at home management decisions. PEF is more convenient and
cheaper than FEV1. PEF as % previous best value or % predicted most
useful
Pulse oximetry Necessary to determine adequacy of oxygen therapy and need for arterial
blood gas measurement. Aim of oxygen therapy is to maintain SpO2 92%
Blood gases
(ABG)
Necessary for patients with SpO2 <92% or other features of life threatening
asthma
Chest X-ray Not routinely recommended in patients in the absence of:
• suspected pneumomediastinum or
pneumothorax
• suspected consolidation
• life threatening asthma
• failure to respond to treatment
satisfactorily
• requirement for ventilation
Initial assessment – the role of symptoms,
signs and measurements
British Guideline on the Management of Asthma revised Jan 2012

10. Clinical features Clinical features can identify some patients with severe asthma,
e.g. severe breathlessness, tachypnea, tachycardia, silent chest,
cyanosis, accessory muscle use, altered consciousness or
collapse.
None of these singly or together is specific. Their absence does not
exclude a severe attack.
PEF or FEV1 Measurements of airway calibre improve recognition of severity and guide hospital or
at home management decisions. PEF is more convenient and cheaper than FEV1.
PEF as % previous best value or % predicted most useful
Pulse oximetry Necessary to determine adequacy of oxygen therapy and need for arterial blood gas
measurement. Aim of oxygen therapy is to maintain SpO2 92%
Blood gases (ABG) Necessary for patients with SpO2 <92% or other features of life threatening asthma
Chest X-ray Not routinely recommended in patients in the absence of:
• suspected pneumomediastinum or
pneumothorax
• suspected consolidation
• life threatening asthma
• failure to respond to treatment
satisfactorily
• requirement for ventilation
Systolic paradox Abandoned as an indicator of the severity of an attack
Initial assessment – the role of symptoms,
signs and measurements
British Guideline on the Management of Asthma revised Jan 2012

11. Levels of severity of
acute asthma exacerbations
Near fatal asthma Raised PaCO2 and/or requiring mechanical ventilation with raised
inflation pressures
British Guideline on the Management of Asthma revised Jan 2012

12. Levels of severity of
acute asthma exacerbations
Near fatal asthma Raised PaCO2 and/or requiring mechanical ventilation with raised
inflation pressures
Life threatening
asthma
Any one of the following in a patient with severe asthma:
• PEF <33% best or
predicted
• SpO2 <92%
• PaO2 <8 kPa
• normal PaCO2 (4.6-6.0 kPa)
• silent chest
• cyanosis
• feeble respiratory
effort
• bradycardia
• dysrhythmia
• hypotension
• exhaustion
• confusion
• coma
British Guideline on the Management of Asthma revised Jan 2012

13. Levels of severity of
acute asthma exacerbations
Near fatal asthma Raised PaCO2 and/or requiring mechanical ventilation with raised
inflation pressures
Life threatening
asthma
Any one of the following in a patient with severe asthma:
• PEF <33% best or
predicted
• SpO2 <92%
• PaO2 <8 kPa
• normal PaCO2 (4.6-6.0 kPa)
• silent chest
• cyanosis
• feeble respiratory
effort
• bradycardia
• dysrhythmia
• hypotension
• exhaustion
• confusion
• coma
Acute severe
asthma
Any one of:
• PEF 33-50% best or predicted
• respiratory rate 25/min
• heart rate 110/min
• inability to complete sentences
in one breath
British Guideline on the Management of Asthma revised Jan 2012

14. Levels of severity of
acute asthma exacerbations
Near fatal asthma Raised PaCO2 and/or requiring mechanical ventilation with raised
inflation pressures
Life threatening
asthma
Any one of the following in a patient with severe asthma:
• PEF <33% best or
predicted
• SpO2 <92%
• PaO2 <8 kPa
• normal PaCO2 (4.6-60 kPa)
• silent chest
• cyanosis
• feeble respiratory
effort
• bradycardia
• dysrhythmia
• hypotension
• exhaustion
• confusion
• coma
Acute severe
asthma
Any one of:
• PEF 33-50% best or predicted
• respiratory rate 25/min
• heart rate 110/min
• inability to complete sentences
in one breath
Moderate asthma
exacerbation
• Increasing symptoms
• PEF >50-75% best or predicted
• No features of acute severe
asthma
British Guideline on the Management of Asthma revised Jan 2012

15. Levels of severity of
acute asthma exacerbations
Near fatal asthma Raised PaCO2 and/or requiring mechanical ventilation with raised
inflation pressures
Life threatening
asthma
Any one of the following in a patient with severe asthma:
• PEF <33% best or
predicted
• SpO2 <92%
• PaO2 <8 kPa
• normal PaCO2 (4.6-6.0 kPa)
• silent chest
• cyanosis
• feeble respiratory
effort
• bradycardia
• dysrhythmia
• hypotension
• exhaustion
• confusion
• coma
Acute severe
asthma
Any one of:
• PEF 33-50% best or predicted
• respiratory rate 25/min
• heart rate 110/min
• inability to complete sentences
in one breath
Moderate asthma
exacerbation
• Increasing symptoms
• PEF >50-75% best or predicted
• No features of acute severe
asthma
Brittle asthma • Type 1: wide PEF variability (>40% diurnal variation for >50% of
the time over a period >150 days) despite intense therapy
• Type 2: sudden severe attacks on a background of apparently
well-controlled asthma
British Guideline on the Management of Asthma revised Jan 2012

16. Patients at risk of developing
near fatal or fatal asthma
Severe asthma Adverse behavioural or
psychosocial features
and
Recognised by combination of:
British Guideline on the Management of Asthma revised Jan 2012

17. Patients at risk of developing
near fatal or fatal asthma
and Adverse behavioural or
psychosocial features
Severe asthma
recognised by one or more of:
• previous near fatal asthma
(previous ventilation or
respiratory acidosis)
• previous asthma admission
• requiring 3 classes of asthma
medication
• heavy use of ß2 agonist
• repeated attendances at A&E for
asthma care
• brittle asthma
Recognised by combination of:
British Guideline on the Management of Asthma revised Jan 2012

18. Patients at risk of developing
near fatal or fatal asthma
Severe asthma Adverse behavioural or psychosocial features
recognised by one or more of:
• non-compliance with treatment or monitoring
• failure to attend appointments
• self-discharge from hospital
• psychosis, depression, other psychiatric illness or deliberate
self-harm
• current or recent major tranquilliser use
• denial
• alcohol or drug abuse
• obesity
• learning difficulties
• employment problems
• income problems
• social isolation
• childhood abuse
• severe domestic, marital or legal stress
and
Recognised by combination of:
British Guideline on the Management of Asthma revised Jan 2012

19. Lessons learnt from
studies of asthma deaths
Many deaths from asthma are preventable – 88-92% of
attacks requiring
hospitalisation develop over 6 hours
Factors include:
•inadequate objective monitoring
•failure to refer earlier for specialist advice
•inadequate treatment with steroids
British Guideline on the Management of Asthma revised Jan 2012

21. British Guideline on the Management of Asthma revised Jan 2012

22. British Guideline on the Management of Asthma revised Jan 2012

23. British Guideline on the Management of Asthma revised Jan 2012

24. If the patient did not respond
 NIPPV should be considered in ICU and it is unlikely
it would replace intubation in this unstable patients

25. British Guideline on the Management of Asthma revised Jan 2012

26. Oxygen
 Many patients with acute severe asthma are
hypoxaemic.
 Supplementary oxygen should be given urgently to
hypoxaemic patients, using a face mask, Venturi
mask or nasal cannulae with flow rates adjusted as
necessary to maintain SpO2 of 94-98%.
 Hypercapnea indicates the development of near-fatal
asthma and the need for emergency
specialist/anaesthetic intervention.
British Guideline on the Management of Asthma revised Jan 2012

27. β2-Adrenergic Receptor Agonists
 In most cases inhaled β2 agonists given in high doses
act quickly to relieve bronchospasm with few side
effects1
 SABAs potentially induce additional responses that
may be of benefit in asthma, such as:2
1. Decreased vascular permeability
2. Increased mucociliary clearance
3. Inhibition of release of mast cell mediators.
4. Oxgen driven neubliser : continuoustly given.
1-British Guideline on the Management of Asthma revised Jan 2012
2- Drugs 2009; 69 (17): 2363-2391

28. Corticosteroids
 Corticosteroids are recommended for most patients in
the emergency department, especially:
 Those who do not respond completely to initial SABA
therapy,
 Those whose exacerbation develops even though they were
already taking oral corticosteroids
 Those with previous exacerbations requiring oral
corticosteroids
Drugs 2009; 69 (17): 2363-2391

29.  Steroids reduce mortality, relapses, subsequent
hospital admission and requirement for β2 agonist
therapy.
 The earlier they are given in the acute attack the
better the outcome.
 It is not known if inhaled steroids provide further
benefit in addition to systemic steroids.
 Inhaled steroids should however be started, or
continued as soon as possible to commence the
chronic asthma management plan
Corticosteroids
British Guideline on the Management of Asthma revised Jan 2012

30. Magnesium Sulfate
 Studies report the safe use of nebulized magnesium
sulphate, in a dose of 135 mg-1152 mg, in
combination with β2 agonists, with a trend towards
benefit in hospital admission.
 A single dose of IV magnesium sulphate is safe and
may improve lung function in patients with acute
severe asthma
British Guideline on the Management of Asthma revised Jan 2012

31. Anticholinergics
 Combining nebulized ipratropium bromide with a
nebulized β2 agonist produces significantly greater
bronchodilation than a β2 agonist alone, leading to a
faster recovery and shorter duration of admission.
 Anticholinergic treatment is not necessary and may
not be beneficial in milder exacerbations of asthma
or after stabilization
British Guideline on the Management of Asthma revised Jan 2012

32. Intravenous Aminophylline
 In acute asthma, IV aminophylline is not likely to
result in any additional bronchodilation compared to
standard care with inhaled bronchodilators and
steroids.
 Side effects such as arrhythmias and vomiting are
increased if IV aminophylline is used
British Guideline on the Management of Asthma revised Jan 2012

33. Leukotriene Receptor Antagonists
 There is insufficient evidence at present to make a
recommendation about the use of leukotriene
receptor antagonists in the management of acute
asthma
British Guideline on the Management of Asthma revised Jan 2012

34. Antibiotics
 When an infection precipitates an exacerbation of
asthma it is likely to be viral.
 The role of bacterial infection has been
overestimated.
 Routine prescription of antibiotics is not indicated for
acute asthma.
British Guideline on the Management of Asthma revised Jan 2012

35. Heliox
 The use of heliox, (helium/oxygen mixture in a ratio
of 80:20 or 70:30), either as a driving gas for
nebulizers, as a breathing gas, or for artificial
ventilation in adults with acute asthma is not
supported on the basis of present evidence.
British Guideline on the Management of Asthma revised Jan 2012

36. Heliox
 A systematic review of ten trials, including 544
patients with acute asthma, found no improvement in
pulmonary function or other outcomes in adults
treated with heliox, although the possibility of benefit
in patients with more severe obstruction exists.
British Guideline on the Management of Asthma revised Jan 2012

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