Pulse January 2018
19
Objective tests in adults aged 17 and over with suspected asthma
AbbreviationsFeNO: fractional exhaled nitric oxideBDR: bronchodilator reversibility
Does spirometry show an obstruction?
Is there reversible airfl ow obstruction?
Are FeNO levels 40ppb or more?
Are FeNO levels 40ppb or more?
Are FeNO levels between
25 and 39ppb?Is there variability in peak-fl ow readings?
Is there variability in peak-fl ow readings?
Are FeNO levels between
25 and 39ppb?
Is there airwayhyperreactivity?
Is there airwayhyperreactivity?
Diagnose with
asthma
Consideralternative
diagnoses orreferral fora secondopinion
Suspectasthma and
reviewdiagnosis
aftertreatment
Consideralternative
diagnoses orreferral fora secondopinion
Diagnose with
asthma
Suspectasthma and
reviewdiagnosis
aftertreatment
Consideralternative
diagnoses orreferral fora secondopinion
Diagnose with
asthma
Is there variability in peak-fl ow readings?
Is there variability in peak-fl ow readings?
Yes
Yes
Yes
Yes
Yes Yes
Yes Yes
No
No No NoNo
No
No
No No
No
No
No
Yes No
Yes
Yes
Yes
Are FeNO levels 40ppb or more?
Test yourself:viral infections
page 39
Yes
Positive test thresholdsObstructive spirometry: FEV1/FVC ratio less than 70% (or below the lower limit of normal if available)FeNO: 40ppb or moreBDR: improvement in FEV1 of 12% or more and increase in volume of 200ml or morePeak-fl ow variability: variability over 20%Direct bronchial challenge test with histamine or methacholine: PC20 of 8mg/ml or less
This algorithm is based on recommendations from NICE’s guideline on asthma: diagnosis, monitoring and chronic asthma management (published November 2017)
p18,19 Jan 2018 Asthma guidance_v6Y.indd 19 20/12/2017 20:52
