Acute Sever Asthma introduction and management.ppt

Acute sever asthma introduction

1. Section 2: f
Acute Severe Asthma
Dr. Abdu Alhmadi

2. Definition of severe asthma
•Patients who need high dose inhaled
CCS and long-acting ß2 agonists and:
–are still uncontrolled
–experience frequent acute exacerbations
–and/or often require emergency treatment
and/or hospitalization

3. Bronchial Asthma
Spirometric
abnormalities
Central airway
narrowing
Bronchoconstriction
Gas exchange
abnormalities
Distal airway
narrowing
Airway Inflammation
Treatments must be directed towards these two components:
Smooth muscle spasm Inflammation, edema, plugs

4. Features of a severe asthma
exacerbation
One or more present:
•Use of accessory muscles of respiration
•Pulsus paradoxicus >25 mm Hg
•Pulse > 110 BPM
•Inability to speak sentences
•Respiratory rate >25 - 30 breaths/min
•PEFR or FEV1 < 50% predicted
•SaO2 <91- 92%

5. Risk factors for fatal or near-fatal
asthma attacks
•Previous episode of near-fatal asthma
•Multiple prior ER visits or hospitalizations
•Poor compliance with medical treatments
•Allergy
•Recent use of oral corticosteroid (OCS)
•Inadequate therapy:
–Excessive use of β-agonists
–No inhaled corticosteroid (ICS)
–Concomitant β-blockers
Y

6. Physical findings in severe asthma
exacerbations
•Tachypnea. . Hypotention.
•Bradycardia or arrythmias.
•Tachycardia.
•Wheeze, or silent chest
•Hyperinflation
•Accessory muscle use
•Pulsus paradoxicus
•Diaphoresis (profuse sweating)
•Cyanosis
•Sweating
•Obtundation (altered mental state)

7. Causes of asthma exacerbations
•Lower or upper respiratory infections
•Cessation or reduction of medication
•Concomitant medication, e.g. β-blocker
•Allergen or pollutant exposure

8. Differential diagnosis
•COPD
•Bronchitis
•Bronchiectasis
•Endobronchial diseases
•Foreign bodies
•Extra- or intra-thoracic tracheal
obstruction
•Carcinoid syndrome
•.vocal cord ddysfunction
•Vaso-vagal reaction
•Cardiogenic pulmonary edema
•Non-cardiogenic pulmonary edema
•Pneumonia
•Pulmonary emboli
•Chemical pneumonitis
•Hyperventilation syndrome

9. Stages of asthma exacerbations
Stage 1:
Symptoms
•Somewhat short of breath
•Can lie down and sleep through the night
•Cannot perform full physical activities without
shortness of breath
Signs
•Some wheezes on examination
•Respiratory rate, 18
•Pulse 100
•Peak flows and spirometry reduced by 10%

10. Stages of asthma exacerbations
Stage 2:
Symptoms
•Less able to do physical activity due to shortness of
breath
•Dyspnea on walking stairs
•May wake up at night short of breath
•Uncomfortable on lying down
•Some use of accessory muscles of respiration
Signs
•Wheezing
•Respiratory rate 19-20
•Pulse 111
•Peak flows and spirometry reduced by 20+%

11. Stages of asthma exacerbations
Stage 3:
Symptoms
•Unable to perform physical activity without
shortness of breath
•Cannot lie down without dyspnea
•Speaks in short sentences
•Using accessory muscles
Signs
•Wheezing
•Respiratory rate 20-25
•Pulse 120
•Peak flows and spirometry reduced by 30+%

12. Stages of asthma exacerbations
Stage 4:
Symptoms
•Sitting bent forward
•Unable to ambulate without shortness of breath
•Single word sentences
•Mentally-oriented and alert
•Use of accessory muscles
Signs
•Wheezing less pronounced than anticipated
•Respiratory rate 25-30
•Pulse 125+
•Peak flows and spirometry reduced by 40+%
•SaO2 91- 92%

13. Stages of asthma exacerbations
Stage 5:
Symptoms
•Reduced consciousness
•Dyspnea
•Silent chest – no wheezing
Signs
•Fast, superficial respiration
•Respiratory rate >30
•Unable to perform pek flows or spirometry
•Pulse 130 - 150+
•SAO2 <90

14. Severity of asthma as graded by %
predicted FEV1
FEV% predictedSeverity
•70 - 100 Mild
•60 - 69 Moderate
•50 - 59 Moderately
severe
•35 - 49 Severe
•< 35 Very severe:
(life-threatening)

15. Acute severe asthma - clinical assessment
•Respiratory frequency: (count)
–Speech: sentences, single words
•Auxiliary respiratory muscle use
•Posture: sitting, can patient lie down?
•Airway patency: rhonchi, silent chest (PEF)
•Respiration: cyanosis (SaO2, blood gases)
•General appearance, effort of breathing: activity level
(pulse rate)

16. Acute severe asthma - monitoring
•Clinical condition
•PEF or FEV1
•PaO2 and PaCO2

17. Acute severe asthma
Admission and close monitoring in hospital unit:
•Clinical stage 4
•PEF or FEV1 < 30% of personal best
(if unknown < 30% predicted)
•PaCO2 > 6 kPa
•PaO2 < 8 kPa
•Poor response to initial treatment

18. Acute severe asthma treatment
Oxygen by nasal cannulae or mask
Inhaled broncodilator should be administered at
regular Intervals:
Nebulised ß2-agonist combined with anticholinergic each
20 mins in the first hour, then hourly as necessary
Systemic steroid should be utilised:
Oral (50-75mg prednisolone) or i.v. corticosteroid (80 mg
Methylprednisolone); repeat after 12 hours; over the following days
40 mg prednisolone or equivalent is usually maintained
Start inhaled high dose steroid as soon as possible

19. Acute severe asthma treatment
Dangerous, or at least ineffective
Dangerous:Sedation
Ineffective: Mucolytics
Physiotherapy
Antihistamines

20. Acute severe asthma treatment
Consider:
Infusion of Beta-2-agonist
Infusion of theophylline
Antibiotics – not all acute asthma exacerbations require
antibiotics
Fluids

21. Acute severe asthma –
treatment options
Standard treatment:
Oxygen
Inhaled beta-2-agonist +/- anticholinergic
Systemic corticosteroid
Additional options:
Systemic beta-2-agonist and/or theophylline, antibiotics, fluids
Nonstandard treatment:
Antileukotrienes; Magnesium sulphate; Heliox; .
Extreme intervention:
Intubation and controlled hypoventilation/other strategy
Anesthesia-sedation; Bronchial lavage

22. Treatment of asthma exacerbations
oral corticosteroids
•Oral corticosteroids are the most powerful medications
available to reduce airway inflammation
•Use until attack has completely abated:
–PEFR and FEV1 at baseline levels
–Symptoms gone
•Taper to QOD and determine if patient can remain well if
corticosteroids are withdrawn completely

23. Oxygen
•Oxygen must be considered as a drug in
a situation of acute asthma
• reducing hypoxic pulmonary vasoconstriction
• ventilation-perfusion mismatch

24. Inhaled B2 agonist
•There is evidence suggesting that continuous
administration of nebulised β2-agonists may
have a better and prolonged bronchodilatory
effect compared to intermittent therapy
•β2-agonist should be administered until
development of significant side effects, a
strategy requiring close monitoring

25. •Nebulizes Salbuterol, 2.5 mg (diluted to 4
mL), in uncomplicated asthma, double
the concentration in severe cases
•Undiluted drug for severe status
asthmaticus.

26. Ipratropium bromide
•The combination of nebulised IB with a nebulised ß2
agonist has been shown to result in greater
bronchodilatation than a ß2 agonist alone.
•The most severely affected patients benefit the most, and
IB should be considered in combination with inhaled ß2
agonists :
•More severe forms of asthma
•Early in the acute attack,
•If there is an incomplete response to inhaled ß2 agonists on their own
•May be repeated every 20 min for the first hour and every
four hours thereafter

27. IV Salbutamol
•The use of IV salbutamol (15 mcg/kg as a once-off
dose) in the early management of acute severe
asthma has been shown to reduce the duration of
the exacerbation and hasten the discharge from
hospital .
•In the intensive care unit IV salbutamol by
continuous infusion is effective and probably safer
than aminophylline.
•Side effect
•Cardiovascular in nature
•hypokalemia

28. IV aminophelline
•The positive effect from theophylline infusion on acute
asthma is well documented, as are the potential for side
effects and severe or even fatal complications
•May be used in cases of near fatal or life threatening
asthma in the intensive care unit.
•Inhaled drugs may have limited effect in nearly complete
airway obstruction and have practical limitations in
ventilated patient. a 6-mg/kg aminophylline load
followed by a 1-mg/kg/h infusion.

29. Adrenalline
•Adrenaline 0.01 ml/kg of a 1:1000 solution
administered subcutaneously may be used
in patients who are moribund on presentati
on to the ED, or where inhaled therapy is n
ot available.

30. Magnesium sulphate
•Magnesium cause smooth muscle relaxation secondary to inhibition
of calcium uptake.
•A single dose of IV magnesium sulphate has been shown to be safe a
nd effective in those patients with acute severe asthma who have had
a poor response to initial therapy.
•The response to magnesium appears to be best in patients who pres
ent with very severe illness.
•The dose is 25 - 50 mg/kg/dose (maximum 2 g) by slow IV infusion.

31. Acute severe asthma
•Treat the condition symptomatically
•Determine what caused the exacerbation:
–inhalant allergen
–food allergen
–drug reaction (ASA, vaccination, etc)
–infection
–worsening of a chronic condition:
- poor therapy compliance
- treatment needs adjustment

32. Prevention of relapse and recurrence
of asthma exacerbation - definition
Relapse:
Reappearance of asthma symptoms that require
unscheduled care within 3 weeks of an asthma
exacerbation
Recurrence:
Reappearance of asthma symptoms that require
unscheduled care more than 3 weeks after the
asthma exacerbation

33. Prevention of relapse and recurrence
of asthma exacerbation
Patients treated for an asthma
exacerbation are at risk for
subsequent severe attacks:
(unscheduled doctor visits,
Emergency Department visits,
hospitalization, asthma death)
Proper asthma care can reduce
this risk:
a)Pharmacological intervention with ICS
b)Patient education – knowledge and skills
c)Self management plans and follow up

34. THANKS