Acute asthma attacks are terrifying episodes for the person who experiences an attack and for those in whose presence they occur. As the management goal of asthma has shifted to mastering the control of symptoms and minimising exacerbations, we are still often tasked with managing acute presentations of asthma as medical officers both within our own clinical environment and in our hospital institutions. Despite an increased range of medicines, widespread dissemination of guidelines and plans for proactive care, an acute severe asthma attack remains one of the most common emergencies general practitioners face. We need a clear and simple plan for our staff and a systems approach to deal with the acute situation. But as GPs, we also have a proactive role in being aware of when an attack is likely to come across as an emergency and, for those who do, negotiating appropriate follow-up care. Asthma mortality in Australia peaked in 1989 and has been declining since; 314 Australians died from asthma in 2003, a 21% decline from 2002. Most asthma deaths occur in the elderly, but there is often diagnostic uncertainty in this age group. Asthma mortality rates are increased in rural areas.2 Some deaths are probably associated with patients – and doctors – not recognising their asthma and the seriousness of the attack. 'At risk' patients • Frequent visits to the GP or emergency department with acute asthma or hospital admission in the last 12 months • Previous life threatening attack or admission to an intensive care unit • No preventive medications/over reliance on inhaled bronchodilators • Patient denial • Poor adherence/inadequate treatment • Failure to notice asthma symptoms • Immediate hypersensitivity to foods, especially nuts • Asthma triggering by aspirin or other nonsteroidal anti inflammatory drugs (NSAIDs) • Poor access to health services There are other issues contributing to patients who return to an emergency department with asthma. A new Australian research identified that one third of patients who had recurrent admissions to the emergency department had avoidable factors. This was associated with low asthma literacy and access to medicines through various barriers. Assessing severity Severity is the first question narrowed down to two questions is it asthma - and not another cause of an acute respiratory obstruction, and is it life threatening? A quick history and expedient physical should answer these two questions. For the acutely distressed patient start oxygen and short acting beta 2 agonist immediately, and when severe and even life-threatening the patient should go immediately to the local emergency department. Remember wheeze is not a good marker for the severity of an attack and may be absent in even the most severe asthmatics. Initial spirometry and/or peak flow measurement will give objective evidence of the degree of airflow obstruction, although in the most severe attacks, initial treatment is overkill. The spectrum of chronic disease severity in adult patients presenting to general practice remains roughly in the range of mild and moderate severity in 2001, with only a small proportion reported at the severe end. The largest proportion of our children with episodic asthma report isolated episodes and for the most part, have been initiated by an upper respiratory tract infection at 6-8 weeks, or so. There are some asymptomatic intervals between episodes; within this range, a spectrum exists from mild to acute episodes. Of these, the majority are sufficiently mild, however, that this accounts for up to 60 percent of pediatric asthma admissions to hospital. Remember that any of the severe or life threatening features of asthma means that the attack should be counted as severe.
Emergency treatment
The mainstay of therapy remains oxygen and inhaled beta 2 agonists. Beta 2 agonists can be administered continuously for life in severe to moderate asthma. Adults Oxygen - use in all but a mild attack. Use a high flow of at least 8 L/min and monitor by oximetry. In an emergency department setting, with severe attacks or those not responding, arterial blood gas monitoring is needed. Nebulised beta 2 agonists - if moderate or severe give 2 x 5 mg salbutamol nebules or 2 mL of 0.5% salbutamol + 2 mL saline. How often this is needed depends on response, but in a moderate attack this dose may be needed every 1-4 hours, and may be continuous in severe asthma that does not respond to the initial dose. The use of intravenous beta2 agonists has been suggested in the management of severe and life-threatening asthma, but a Cochrane review concludes that there is no evidence to support this. If the attack is mild or moderate or if oxygen is not available to run the nebuliser, a spacer and metered dose inhaler can be used. A dose of 12 puffs (each separately) is equivalent to 5 mg nebulised of salbutamol.Nebulised ipratropium bromide - this is recommended for severe attacks, 500 μg nebulised with salbutamol every 2 hours.
Steroids - systemic (not inhaled) steroids are required, and their early use within 1 hour of the onset of symptoms reduces the need to admit patients to hospital. Adults with moderate or severe attacks require 250 mg stat IV hydrocortisone; In hospitalised patients, this should be 250 µg every 6 hours for the first 24 hours and then reviewed. A patient with a moderate attack may receive an oral dose of 0.5-1.0 mg/kg; oral steroids should be considered for a mild attack. IV aminophylline: At most inhaled beta 2 agonists, the addition of IV aminophylline does not increase bronchodilation. Adverse side effects are obvious, however. Adrenalin: Its use is necessary with anaphylaxis and respiratory arrest. Anaphylaxis: Administer 0.5 mL of adrenalin 1:1000 intra-muscularly. Respiratory arrest. Administer 5 mL 1:10 000 at a slow rate IV. Other treatments - The effectiveness of other emergency treatments is still unknown, such as but not limited to heliox in the non-sedated patient. Further research may someday prove a role for noninvasive positive pressure ventilation in the treatment of status asthmaticus.
Children
Oxygen - monitor with oximetry but not often necessary in a mild or moderate attack.Inhaled beta 2 agonists - there is now a fair amount of experience in the use of a spacer and metered dose inhalers. The important point is that below the 6 year age group, a small volume spacer is combined with a mask and the material is loaded once and then the dose is used up to one time. And for salbutamol; 6 is the equivalent volume for a 2.5mg dose, and this, in proportion, requires a 5mg dose which is equivalent to 12 volumes.
Initial treatment 6-12 puffs and reassessment in 20 minutes. If that response is unsatisfactory then repeat every 20 minutes until two more have been administered. So in a moderate attack this equates to three in the first hour and after this period further administrations are every 1-4 hours. Continuous nebulised salbutamol is indicated when an attack has become potentially life-threatening.
Systemic steroids: oral prednisolone should be given as a daily dose of 1 mg/kg for 3 days, but may be increased gradually depending on whether the child remains on regular high doses of inhaled corticosteroids. IV methylprednisolone is started with 1 mg/kg every 6 hours for a total of 1 day in any patient who requires such treatment during an acute and life-threatening attack.
Other treatments - the role of ipratropium, even during severe exacerbations, is not clearly defined. Aminophylline has no role outside the intensive care unit.
First aid/emergency plan - the recommended plan for community first aid is the 4 x 4 x 4 plan. It recommends 4 puffs of reliever, one puff at a time, with 4 breaths after each puff. Wait 4 minutes then repeat (see Patient Education this issue). In an emergency, 'make do' spacers, eg. paper cups, small soft drink bottles, are effective.
Other key information
Important information to be obtained will include the duration of this attack and the response to medication. The worse the course, the greater the duration of the symptom and the failure of response to therapy; and exhaustion and muscle fatigue may lead to respiratory failure. Other important information will include establishing the causes of the current exacerbation, the use of, and adherence to, asthma medications, as well as significant asthma and other history. There are many causes of dyspnea in elderly patients, and multiple morbidities often coexist. Don't forget to ask about other medications that may precipitate asthma flares, such as NSAIDs and complementary medicines.What to do if the patient does not respond
If your patient is not responding to initial therapy, think again about your assessment of severity and other possible diagnoses. • Could the child have a foreign body? • Is this an allergic or hypersensitivity reaction that I have not yet developed? • In the older patient, is this a complication of heart failure or chronic obstructive pulmonary disease? • How much of a problem does this coexisting illness represent? If it is asthma, treat for an acute attack, but pay attention to possible complicating factors such as the presence of an underlying pneumonia, or even a pneumothorax. Neither the adult nor the child needs a chest X-ray unless there are focal findings or a failure to respond to treatment. In severe manifestations: sometimes it is difficult to distinguish between the extremes;
Admit for:
both, at all times, when possible, without judgement – and emergency plans will include the following: Arrange an ambulance with as little delay as possible. Mild acute attacks that have responded to first line treatment are rarely sent to hospital, you can simply keep them in the surgery for an hour under your watch. Factors that may influence the choice to admit include: • duration of symptoms – the longer the duration for an exacerbation, the greater the chance for admission • response to initial therapy • past history of admission for asthma • comorbidities, and • lack of home care.
Follow up
This is one of the most important steps. We know there are preventable factors in patient re-presentation in emergency situations. But we often do not know as much about our patients' self-reporting, their social background or trigger factors as we would when discharged home from practice. • review of medications (consider a short course of oral steroids, in addition to a long acting beta agonist) • a written asthma action plan, and • detailed advice about what to do if things get worse in the next 24 hours. Monitor as an outpatient for a period of 24-48 hours and begin active care with the Asthma 3+ plan. The patient should be seen by their general practitioner immediately after discharge as well as any follow-up appointments in the hospital. A study conducted in Canada last year showed that, compared to a control group, at 6 months post discharge from an emergency department, patients who scheduled an appointment with their primary care provider and who received at least one reminder call for their follow-up had higher scores in asthma quality of life, fewer asthma symptoms, and were more likely to have written an asthma action plan. The differences resolve at 12 months and the issue of long-term follow-up in asthma seems to be left once again at the doorstep of GPs. Perhaps, a crisis may be the best time to approach a patient about their asthma and then be able to share a meaningful partnership in managing asthma.
