Authors: Becky Maxwell, Chris Connolly / Code: CAP3, HAP6, RC1, RP2, RP5, SLO1, SLO2, SLO3, SLO5 / Published: 16/11/2016
This guideline was published in 2016 and was an update on the previous iteration that has been updated yearly by SIGN.
The full guideline can be found over on the BTS website
This Guideline is important for us as Emergency Physicians as we see lots of acute dyspnoea, wheezy adults not to mention lots of kids that may be recurrent attenders at our Emergency Departments with viral wheeze and asthma especially now we’re heading in to the colder months.
During this podcast we will discuss diagnosis, treatment of acute exacerbations, some non-medical therapies and some special circumstances.
We’re probably not the most appropriate doctors to make the first diagnosis of asthma as we’re probably only seeing folks when they’re sick, but having done a winter or two in a Paediatric Emergency Departments we have been exposed to loads of wheezy kids, and loads of stressed parents who want to know ‘is it asthma?’
So there are a few things we should know aren’t there? Most importantly it’s not all about spirometry and Peak flow.
In fact, the SIGN guys are really pragmatic here. The diagnosis is a clinical one, the absence of a gold standard test means they can’t make unequivocal evidence based recommendation on how to diagnose.
Central to everything is the patient and their symptoms; they should have at least one of cough, wheeze, SOB or chest tightness. The clever objective tests try to build the clinical picture further, and demonstrate variable airflow when well/unwell.
It is worth noting that in adults these symptoms have poor sensitivity and specificity and that in kids nearly all asthmatic patients have the symptoms but only a ¼ of those with the symptoms have asthma.
As clinicians it is critical to think if the wheeze in this patient could be an alternative diagnosis other than asthma? Smoking increases the likelihood that it’s COPD, think about obesity and dysfunctional breathing too, these can be a really tough group in the real world. Often these patients have been labeled as asthmatic before, or had childhood wheezy episodes and they can get themselves looking pretty sick. Once the diagnosis is made it can be pretty difficult to change.
Diurnal variation can be significant – classical cough is worse at night – but then isn’t it always? When Chris survived man-flu he can vividly remember the cough being particularly troublesome at night.
So what can we tell the patient or parent?
When we suspect asthma presenting acutely with a LRTI/URTI we tend to say to the patient ‘I can hear some wheeze today and some symptoms you describe could point towards a diagnosis of asthma, however, I want you to see the GP when things have settled down to get the history down in more detail and to consider if any tests will help you’.
Right diagnosis made, onto the meat…Acute Asthma Management:
The advice in this guideline is based on evidence and lessons learnt through the National Confidential Enquiry into Asthma Death.
People who died were more likely to
- Have chronic severe asthma
- Had inadequate steroid management and inadequate monitoring of their chronic disease. There seemed to be a failure of written advice and management plans in these patients – in our mind this is second nature in children but we absolutely need to get better at this in adult patients
- Deaths continue to be reported associated with beta blocker or NSAID prescriptions – all asthma patient should be asked about previous exposure and reactions to these meds!
- There is increased risk of death within a month of discharge from hospital so primary care follow up is essential and ties in with the written management plan
- Behavioural/psychosocial features were important: the presence of learning disability, psychosis, poor compliance, and failure to attend clinic appointments, alcohol/drug use and self discharge from hospital.
Just to reiterate what investigations we should in the asthmatic patient:
- Chest X-ray: Reassuring nothing changed in this guideline – only do it if pneumonia or Pneumothorax is suspected or if the patient is deteriorating
- Arterial Blood Gas: should be done if oxygen saturations <92 % irrespective if patient is on air or receiving oxygen therapy
- O2 – aim for Saturations 94-98%
- Salbutamol: nebulisers should be oxygen driven in adults; start with repeated doses, if patient does not respond continuous nebulisers should be given. The Guideline suggest you can use spacers in adult patients in all but life threatening asthma presentations -we find it more convenient to reach for the nebuliser
- Steroids: SIGN recommends giving 40-50mg prednisolone or 400mg IV hydrocortisone. Continue 40-50mg for 5 days on discharge. To us this seems like a bigger dose than we are prescribing… we’d be interested in hearing if others are regularly prescribing big steroid doses
- Magnesium: there is no role of nebulised magnesium. IV bolus dosing may provide some benefit in acute severe asthma. The guideline states that the trials are of varying quality and difficult to know when in the treatment cycle the magnesium is given, however the harm profile is lower. It may be worth refreshing your memory on the 3Mg study published in the Lancet, St Emlyn’s have reviewed this in a blog post if you want a quick read of the important points
- Ketamine: The Guideline is not clear on Ketamine’s effectiveness as a specific treatment for asthma. There is no good evidence for ketamine – further trials are needed before the Guideline can recommend it. There are a few small randomised controlled trials and approximately a dozen case studies but no big RCT on the use of Ketamine in asthma although we are both still going to reach for it!
- NIV: shouldn’t replace IPPV in those with hypercapnic ventilatory failure
HELIOX, Nebulised furosemide, oral leukotriene receptor antagonists are NOT recommended within the remit of the Guideline. We had never heard of nebulised Furosemide so decided to look for some evidence and came up with this Best Bet in the EMJ
Finally, they recommend the use of checklists and protocolised care…
On discharge use the chance to do some asthma education: technique, PEFR diary, smoking advice etc.
They also have a list of recommended admissions even if they have improved:
- the patient still has significant symptoms
- concerns about adherence
- living alone/socially isolated
- psychological problems
- physical disability or learning difficulties
- previous near-fatal asthma attack
- asthma attack despite adequate dose steroid tablets prior to presentation – this surprised us somewhat and not something we had considered to be honest…..
- presentation at night
For us it was an interesting Guideline we found the limited evidence of Ketamine surprising and the limited role of NIV outside ICU as new. We both vow to ensure patients are followed up in an appropriate fashion and will reiterate the importance of a written plan for adults on discharge – another few things for Chris’ growing list of mid year resolutions……
- Still limited role of ketamine and NIV as a treatment outside of ICU
- Importance of follow up and written plans reiterated.
We’ll see you next month with a perspective on the Guideline from a paediatric point of view…