Tips on managing asthma in children

Transcription

1 Tips on managing asthma in children Dr Ranjan Suri Consultant in Respiratory Paediatrics Bupa Cromwell Hospital Clinics: Friday (pm)

2 Asthma in Children Making the diagnosis Patterns of childhood asthma BTS Guidelines Medication Acute asthma management Other items of interest

3 Making the diagnosis recurrent wheeze and/or cough where asthma is likely (Warner J, Arch Dis Child 1992; 67:240-8)

4 Recurrent symptoms Wheezing Cough Difficulty breathing Chest tightness

5 Increased probability of asthma Symptoms: are worse at night and in the early morning Triggered by exercise, pets, cold or damp air, emotions or laughter occur apart from colds

6 Increased probability of asthma Personal history of atopic disorder Family history of atopy Widespread wheeze heard on auscultation Improvement with adequate therapy

7 Asthma unlikely Symptoms with colds only, with no interval symptoms Isolated cough Absence of wheeze or difficulty breathing History of moist cough

8 Asthma unlikely Repeatedly normal physical examination of chest when symptomatic Normal PEF or spirometry when symptomatic No response to a trial of asthma therapy Clinical features pointing to alternative diagnosis

9 15 year old boy Severe persistent cough. Loud, explosive, very distressing cough. No improvement with inhaled and oral steroids, bronchodilators, and antibiotics. CXR normal. Spirometry:

10 Flow volume loop

11 The Diagnosis Further History: all coughing disappeared when asleep, normal respiratory rate and pattern. Diagnosis: Habit/honking cough.

12 Patterns of asthma Infrequent episodic asthma episodes 6-8 weeks or more apart attacks generally not severe symptoms rare in between attacks normal examination and lung function between attacks > 6 weeks

13 Patterns of asthma Frequent episodic asthma attacks < 6 weeks apart attacks more troublesome minimal or no symptoms between attacks normal examination and lung function between attacks often seasonal (winter months) < 6 weeks

14 Patterns of asthma Persistent asthma symptoms between attacks sleep disturbance > 1 night/week exercise induced wheeze / limitation use of beta 2 agonists > 3 times per week abnormal lung function between attacks

15 Patterns of asthma in children infrequent episodic ~ 65-75% frequent episodic ~ 20-25% persistent ~ 5-10%

16 Children age 5-12 yrs

17 Children age 5-12 yrs

18 Children age 5-12 yrs

19 Children age 5-12 yrs

20 Children age 5-12 yrs

21 Children age 5-12 yrs

22 Children Less than 5 yrs

23 Children Less than 5 yrs

24 Children Less than 5 yrs

25 Children Less than 5 yrs

26 Children Less than 5 yrs

27 Inhaled corticosteroids CFC beclamethasone (Becotide) fluticasone (Flixotide) budesonide (Pulmicort) aerosolised beclamethasone (QVAR) BDP=BUD 1 FP=QVAR 2 relative potency

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29 Clinical effect Dose - response curve for inhaled corticosteroids 90% max Clinical Benefit Adverse effect Daily dose of inhaled steroid (FP ug) Holt et al. BMJ 2001;323:1-8

30 Long-acting β2 agonists (LABA) Salmeterol ( Serevent ) onset 20 mins duration 12 hours partial agonist MDI/accuhaler Eformoterol ( Oxis ) onset 3-5 mins duration 12 hours full agonist turbohaler only

31 When to add long acting b2 agonist? Uncontrolled asthma at mcg/day BDP Increasing ICS>500mcg fluticasone unhelpful, LABA offer more symptom control (Greening 1994, Woolcock 1996, MIASMA 2000) Not to be used as single agent (Nelson 2006, Rodrigo 2009)

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33 Combination inhalers Seretide and Symbicort One product that treats the two underlying components of asthma inflammation and bronchoconstriction LABA ICS Controls the symptoms Reduces inflammation Prevents exacerbations Seretide Symbicort

34 Symbicort single agent Use of symbicort as both maintenance and reliever therapy (SMART). Symbicort (200/6) 1 puff BD and PRN Better asthma outcomes Lower dose Improved adherence Scicchito 2004, O Byrne 2005, Rabe 2006

35 Leukotriene modifiers Leukotriene receptor antagonists montelukast (Singulair) zafirluakast (Accolate) 5-lipoxygenase inhibitor zileutin

36 Montelukast monotherapy Intermittent asthma/viral induced wheeze Montelukast daily for at least 1 week Reduction: Hospitalisation Duration of episode Prednisolone use Bisgaard 2005, Robertson 2007

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43 Age appropriate drug delivery Delivery System MDI and spacer mask no mask turbohaler accuhaler autohaler Age <8 years 0-5 years 5 years >8 years >8 years >8 years

44 Inhaler Therapy in Children Review regularly Assess adherence Assess inhaler technique Monitor control Adjust therapy to minimum dose required to maintain control

45 Disadvantages of nebulisers Difficult to operate and maintain Need external power source Inefficient method of drug delivery % of drug lost when mask held away from the face Ventilation/perfusion mismatch

46 Nebuliser vs Spacer Acute Asthma Morgan et al BMJ 1982; 285: Freelander et al BMJ 1984; 288: Fuglsang et al Eur J Resp Dis 1986; 69: Lee et al J All Clin Immunol1987; 87:307 Ba et al J Asthma 1989; 26:355-8 Pendergast et al MJA 1989; 151:406-8 Pierce et al MJA 1992; 156:771-4 Karem et al J Pediatr 1993; 123:313-7 Parkin et al Arch Dis Child 1995; 72: Lin et al Arch Dis Child 1995; 72:214-8

47 Nebuliser vs Spacer Acute Asthma Randomised, double blind, placebo controlled trial in A&E, 1-4 year olds 6 puffs salbutamol pmdi/small vol spacer vs 2.5 mg nebulised salbutamol (every 20 min, 6 doses) Laversha et al, Auckland 1997

48 Nebuliser vs Spacer Acute Asthma Clinical score, SaO2 MDI = neb Reduction in wheeze MDI>neb HR neb>mdi Admission rate MDI 31% neb 62% Cost MDI $787 neb $1298

49 Acute asthma Salbutamol as needed Prednisolone 2mg/kg (max 40mg) for 3 days (usually once requiring salbutamol 10 puffs 4 hourly)

50 Acute Asthma to double or not to double? Randomised, placebo controlled, double blind study in children At exacerbation take usual medication plus Study pmdi (800mcg BDP or placebo) Garrett, Arch Dis Child 1998

51 Acute Asthma to double or not to double? PEFR (day/night) steroid increase = placebo PF variability steroid increase = placebo symptom scores steroid increase = placebo spirometry steroid increase = placebo parents assessment steroid increase = placebo

52 Asthma Management Plan Personalised Key Elements: Interval medication (reinforce delivery) Medication to take with exercise Management of exacerbations Emergency management Bring this plan and your medications everytime you come to the doctor

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54 Peak Flow Monitoring Uncertain role in childhood asthma Unreliable < 6yo?Accuracy at home?detect severe disease Occasional (older) child unable to perceive severe airway obstruction

55 Spirometry & Flow Volume Loop Actual (L) Predicted% FVC FEV MMEF FEV1/FVC 54 PEF

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57 Asthma and Passive Smoking (Chilmoncyz et al, NEJM 1993;328:1665-9) 199 children with asthma (8mo-13yr) from allergy/asthma practice Exposure to smoke: history urine cotinine Outcomes: exacerbations lung function

58 Results: Asthma and Passive Smoking (Chilmoncyz et al, NEJM 1993;328:1665-9) 1. Exacerbations increased with exposure RR 1.8 (95%CI ) reported exposure RR 1.7 (95%CI ) measured exposure 2. FEV 1, FEF 25-75, FEV 1 /FVC decreased with increasing exposure

59 Key tips Asthma is a clinical diagnosis Use age appropriate inhaler device Assess adherence Assess inhaler technique If no improvement, is diagnosis correct?

60 Thank you! How to refer? Call