EMed

Acute Asthma Mx

Background

Consider the following for all patients with severe asthma

Nasal prongs and highest tolerable O₂flow. This can be given in addition to the 6 litres O₂/min driving the nebuliser
IV fluids (2 l for average adult) on basis that the patient is dehydrated
IV magnesium 2g over 5 - 10 minutes has been shown to be useful [Cochrane]
Start systemic steroids early [Cochrane]
The use of intravenous beta 2 antagonists is controversial [Cochrane]

Management

Normal Peak Flow in Men

Height (top row = metres, 2nd row =inches)
♂	1.55	1.6	1.65	1.7	1.75	1.8	1.85
Age	61	63	65	67	69	71	73
25	515	534	552	570	589	607	625
30	502	520	539	557	576	594	612
35	489	508	526	544	563	582	600
40	476	495	513	531	550	568	586
45	463	482	501	519	537	556	574
50	450	469	487	505	524	543	561
55	438	456	475	493	511	530	548
60	424	443	462	480	498	517	535

Normal Peak Flow in Women

Height (top = metres. Second row =inches)
♀	1.45	1.5	1.55	1.6	1.65	1.7	1.75
Age	57	59	61	63	65	67	69
25	365	383	400	416	433	449	466
30	357	374	390	407	423	440	456
35	348	365	381	398	414	431	447
40	339	356	372	389	405	422	438
45	330	347	363	380	397	413	429
50	321	338	354	371	388	404	420
55	312	329	345	362	379	395	411
60	303	320	336	353	370	386	402

Links

Irish NCEC 2015 Asthma guideline
2019 Joint BTS / SIGN guidelines on Mx of asthma (quick reference guideline)
Local copy BTS/SIGN 20129 Quick Ref Assessment, Treatment
For all "Mild / moderate" (step 2 BTS guidelines) who reach discharge criteria, please ensure they have increased inhaled steroids (e.g. Alvesco 160ug single dose MDI daily[Alvesco Details]), oral steroids (5 days) and a B2 agonists
How to use a Spacer / MDI

Content by Dr Íomhar O' Sullivan. Last review Dr ÍOS 19/04/23.