The Least Imperfect Device Karen Meade Clinical Nurse Specialist The Hillingdon Hospital

The Development of Inhalers 1956 first pMDI 1968 first DPI (Sodium Cromoglycate) 1974 first breath actuated device 1977 first single dose DPI 1980 first large volume spacer 1988 first multi-dose DPI 1998 combination inhalers On-going transition to CFC free pMDI’s Snell (1995)

Why Use Inhalers? n Rapid action n Smaller doses Fewer side effects Fewer side effects Pauwels 1993, Ariyananda et al 1995

Why is the device important ? Efficacy of treatment depends on; n Physical factors n Mode of inhalation n Patency of airways n Patient compliance n Patient ability Ariyananda et al 1995, Weller 1999, DTB 2000, Lenney et al 2000

Characteristics of the Ideal Device - 1 n reliability & reproducibly delivers a predetermined dose of drug n easy to use n cost effective n portable n easy to assess technique n low oropharangeal deposition n available in a range of therapies

Characteristics of the Ideal Device - 2 n suits all settings n integral cap / cover n dose counter / able to tell when empty n environmentally friendly n available in primary, secondary & tertiary care n easy to identify preventer/reliever Raine & Newberry 1991, Hanley 1995, Hobbs 1995, NARTC 1997, DTB 2000

Main device types n Aerosol –Pressurised metered dose inhaler (pMDI) –Breath actuated n Dry powder (breath actuated) inhalers –Turbohaler –Accuhaler –Diskus –Clickhaler –Diskhaler –Rotahaler

Pressurised Metered Dose Inhalers (pMDI)

Beclomethasone 50 Beclomethasone 250 Beclozone easi breathe 250 Beclomethasone (QVAR)100 Beclomethasone (QVAR) 50 Metered dose inhaler devices

Metered dose inhalers - pMDI Metered dose inhalers - pMDI 7-20% drug delivery + range of therapies + cheap + portable Leech(1998), DTB(2000), NARTC(1997) - need co-ordination - no dose counter except in combined medications - oro-pharangeal deposition - cold freon effect

Spacer devices – large and small volume spacer devices

Spacers 15-30% drug delivery + reduce oral deposition + tidal breathing acceptable/suitable for during an attack + suitable from birth - wide variation in drug delivery between spacers - bulky DTB(2000), NARTC(1997), Hobbs(1995)

Breath Actuated MDI’s – “Easibreathe and Autohaler”

Breath Actuated MDI’s 15-20% drug delivery + portable + no co-ordination required + lower inspiratory flow required (20- 30L/min) - no dose counter - no LA ß2-agonist - patient may block vents DTB(2000), NARTC (1997), Hobbs(1995)

Dry Powder Inhalers - General points + portable + CFC free + dose counter + breath actuated + suitable for 6+yrs - need higher inspiratory flows - some susceptible to damp NARTC (1997), DTB (2000)

Clickhaler

Clickhaler 10-15% drug delivery + low inspiratory flow (15 L/min) + locks when empty - powder can fall out! - no LA ß2 agonist DTB(2000)

Rotahaler, Spinhaler, Diskhaler, Aerohaler

15% drug delivery + compact +/- taste + able to monitor doses - require reloading - loss of powder - capsule can deteriorate DTB(2000), NARTC(1997), Hobbs(1995)

Handihaler + low inspiratory flow + once a day dosing + audible noise when using it correctly - only available in Tiotropium - needs reloading - susceptible to damp

Accuhaler

Accuhaler 16-21% drug delivery + range of therapies + locks when empty + combination therapy + low inspiratory flow 30-90L/min - requires monthly replacement (60 doses) DTB(2000), NARTC(1997)

Turbohaler

Turbohaler Inhaler devices n Bricanyl, (Terbutaline) n Pulmicort, (Budesonide) n Oxis, (Eformoterol) n Symbicort, 100/6, 200/6, 400/12

Turbohaler 20-30% drug delivery + range of therapies + visible warning when 20 doses left +/- no taste + inspiratory flow L/min - susceptible to damp DTB(2000), NARTC(1997), Hanley(1995)

Patient Preference Studies n Subjective measure n Preference does not correlate with technique n Small studies n Bias n Not reproducible (Hanley 1995, Raine et al 1991, Lenney et al 200, Williams 1995)

Choosing the ‘least imperfect’ device n Drugs required i.e. ß2, ICS, LAß2 n devices available n patient able to demonstrate a good technique & health professional able to check technique n suits all settings n device acceptable to the patient

Checking Technique n Visual check with placebo n Independent check n Inspiratory flow check

Inhaler & Spacer Care n Rinse through MDI’s n Wash spacer once a month & drip dry n Remember to dry well before using n Replace spacer every 6 months n Do not leave DPI in damp environments n Write start date on MDI & expected finish date

The Least Imperfect Device ? The device which the patient can, & will use

Thank you Any questions ?