Asthma

Question 1

What is asthma?

Answer 1

Chronic inflammatory condition

Causes episodic exacerbations of bronchoconstriction - smooth muscles of airways contract causing reduction in airway diameter

Narrowing of the airways causing obstruction to airflow going in and out of the lungs

Airway obstruction is reversible - responds to bronchodilators e.g., salbutamol

Question 2

What are typical triggers for asthma?

Answer 2

Infection

Night time or early morning

Exercise

Animals

Cold/damp

Dust

Strong emotions

Question 3

Which presentation suggests a Dx of asthma?

Answer 3

Episodic symptoms

Diurnal variability - typically worse at night

Dry cough with wheeze + SOB

A Hx of atopic conditions e.g., eczema, hayfever and food allergies

FHx

Bilateral widespread “polyphonic” wheeze

Question 4

Which presentation suggests a Dx other than of asthma?

Answer 4

Wheeze related to coughs and colds - more suggestive of viral induced wheeze

Isolated or productive cough

Normal Ix

No response to Tx

Unilateral wheeze - suggests focal lesion or infection

Question 5

What are the criteria for moderate acute asthma?

Answer 5

50-75% of best/predicted PEFR

Speech normal

RR < 25/min

Pulse < 110 bpm

Question 6

What are the criteria for severe acute asthma?

Answer 6

33-50% of best/predicted PEFR

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RR ≥ 25/min

Pulse ≥ 110 bpm

Question 7

What are the criteria for life-threatening acute asthma?

Answer 7

<33% of best/predicted PEFR

O2 sats < 92%

Silent chest, cyanosis or feeble respiratory effort

Bradycardia, dysrhythmia or hypotension

Exhaustion, confusion or coma

Question 8

What is the immediate Mx for someone that presents with severe or life-threatening asthma?

Answer 8

ABCDE assessment

O2 (maintain SpO2 94-98%)

Salbutamol 5mg nebulised continuous

Ipratropium 0.5mg nebulised 4-6 hourly

Prednisolone 40-50mg PO / hydrocortisone 100mg IV

Question 9

After the immediate Mx for someone that presents with severe or life-threatening asthma, what Ix you do next?

Answer 9

ABG

If SpO2 ≤92% or life-threatening features

Look for markers of severity (acidosis, increased CO2, reduced O2)

Question 10

If the patient with severe or life-threatening asthma shows no improvement despite the initial Mx, what should you do next?

Answer 10

Get senior review

Consider 2g IV magnesium sulphate over 20 mins

Order portable CXR

Question 11

If the patient with severe or life-threatening asthma shows no improvement despite IV MgSO4, what should you do next?

Answer 11

Consider referral to the ITU

Question 12

What are the BTS guidelines for asthma Mx?

Answer 12

Question 13

Sources

Answer 13

UHS ED prompt cards

https://zerotofinals.com/medicine/respiratory/asthma/

https://www.nice.org.uk/guidance/ng80/resources/algorithm-f-pharmacological-treatment-of-chronic-asthma-in-adults-aged-17-and-over-pdf-4656176754

https://www.researchgate.net/figure/Diagram-From-BTS-SIGN-Asthma-Guideline-Showing-the-Step-Up-Step-Down-Treatment-Ladder-a_fig1_341527769

https://bmjopenrespres.bmj.com/content/3/1/e000143