Since BA has airflow obstruction due to airway inflammation and hyperresponsiveness, anti-inflammatory therapy and bronchodilating therapy should be considered.1 Airway inflammation in BA responds to steroid very well, thus inhaled glucocorticosteroids are the first choice for the treatment for BA. Assessment should address daytime symptoms, nighttime symptoms, use of short acting inhaled beta agonists to relieve symptoms, and difficulty in performing normal activities and exercise at each visit. A simplified scheme for recognizing controlled, partly controlled and uncontrolled asthma has been published by GINA1 (Table 1). The management approach to pharmacological treatment is based on increasing medications until asthma is controlled, and decreasing medications when possible to minimize side effects. The patient's management should be adjusted, if needed, at every visit1 (Fig. 1). For example, if asthma is not controlled on the current regimen, treatment should be stepped up until control is achieved. If control has been maintained for at least three months, treatment can be stepped down. The scheme of the pharmacological treatment for BA is shown in Figure 2.1 Commonly used drugs including bronchodilators and glucocorticosteroids are shown in Table 2.

Intermittent (Step 1): Patients with mild intermittent asthma are best treated with a short-acting inhaled beta-2-selective agonist such as salbutamol and procaterol, taken as needed for relief of symptoms.

Mild persistent (Step 2): The distinction between intermittent and mild persistent asthma is important, because the GINA guideline calls for initiation of long-term controller medication in patients with mild persistent asthma.1 The preferred long-term controller for mild persistent asthma is low dose inhaled glucocorticosteroids (Fig. 2). Regular use of inhaled glucocorticosteroids reduces the frequency of symptoms and the need for SABAs for symptom relief. In addition, it improves the overall quality of life, and decreases the risk of serious exacerbations.2 Alternative pharmacological treatment of mild persistent asthma includes leukotriene receptor antagonists. Patients receiving long-term controller therapy also should continue to use their short-acting beta agonist as needed for relief of symptoms.

Moderate persistent (Step 3): The pharmacological treatments for moderate persistent asthma are either low-doses of an inhaled glucocorticosteroids plus a long-acting inhaled beta agonist (LABAs), medium- or high-doses of an inhaled glucocorticosteroids, low doses of an inhaled glucocorticosteroids plus leukotriene receptor antagonists, or low doses of an inhaled glucocorticosteroids plus sustained release theophylline. The combination of low-doses of an inhaled glucocorticosteroids plus LABAs may be more effective in controlling asthmatic symptoms than increasing the dose of inhaled glucocorticosteroids alone.

Severe persistent (Step 4): The preferred treatments for severe persistent asthma are medium- or high-doses of an inhaled glucocorticosteroids in combination with LABA. When patients are inadequately controlled on high-dose inhaled glucocorticosteroids plus LABAs, add a leukotriene modifier (leukotriene receptor antagonist or lipoxygenase inhibitor) and/or sustained release theophylline.

Severe persistent (Step 5): The preferred treatments for severe persistent asthma are high doses of an inhaled glucocorticosteroids plus LABAs. In addition, for patients who are inadequately controlled on high-dose inhaled glucocorticosteroids and LABAs, add lowest dose of oral glucocorticosteroids. Recently, anti-IgE humanized monoclonal antibody omalizumab (Xolair^®) is available in Japan. The anti-IgE therapy omalizumab may be considered in combination with other treatments for very severe asthma patients who are resistant against treatment with high doses of an inhaled glucocorticosteroids plus LABAs.

Patients with mild asthma attack require inhaled rapid-acting beta2-agonists in adequate doses using a metered dose inhaler (MDI). Begin with 2 to 4 puffs every 20 min for first hour. However, patients with acute exacerbations of asthma often require systemic glucocorticosteroids. The best strategy for management of acute exacerbations of asthma is early recognition and intervention, before asthma attacks become severe and potentially life threatening. Previous studies have frequently revealed that failures on the part of both patients and clinicians to recognize the severity of the disease and to intensify treatment appropriately. Thus GINA strongly recommends "Do not underestimate the severity of an attack".1

Assess the severity of the attack as follows.1 Patients should immediately seek medical care if:

1. The attack is severe: for example, the patients is breathless at rest, is hunched forward, talks in words rather than sentences, is agitated, drowsy, or confused, has bradycardia, or has a respiratory rate greater than 30 per minute. Wheeze is loud or absent. Pulse is greater than 120/min. PEF is less than 60% of predicted or personal best, even after initial treatment. The patient is exhausted.

2. The response to initial bronchodilator treatment is not prompt and sustained for at least 3 hours.

3. There is no improvement within 2 to 6 hours after oral glucocorticosteroids is started.

4. There is further deterioration.

Asthma attacks require following prompt treatment.

1. Use inhaled short-acting beta agonists early and frequently. The mainstay of bronchodilator treatment is inhalation of short-acting beta-2-selective adrenergic agonists, such as salbutamol and procaterol. The standard regimen for initial care has become salbutamol (or an equivalent) 1.5 to 2.5 mg by continuous flow nebulization every 20 minutes for the first hour, then 1.5 to 5 mg every 1 to 4 hours as needed. Another protocol calls for administration by MDI with a spacer. Begin with 2 to 4 puffs every 20 minutes for the first hour; then mild exacerbation will require 2 to 4 puffs every 3 to 4 hours, and moderate exacerbation 6 to 10 puffs every 1 to 2 hours.

2. Start systemic glucocorticosteroids if there is not an immediate and marked response to the inhaled short-acting beta agonists. The onset of action of systemic glucocorticosteroids is not clinically apparent until as long as 6 hours after administration. Early administration is though to help to minimize the delay in improvement anticipated with systemic glucocorticosteroids. Oral glucocorticosteroids; the equivalent of a prednisone dose of 40 to 80 mg (0.5 to 1 mg per kg) per day in a single or divided dose is typical. Intravenous glucocorticosteroids should be given to patients who present with impending or actual respiratory arrest, or patients who respond poorly to oral glucocorticosteroids. A massive initial dose (e.g. methylprednisolone 500 mg) is no more effective than a large initial dose (125 mg)3; significantly smaller doses (e.g. 60 to 80 mg) may be sufficient.

3. Oxygen is given if the patient is hypoxemic (achieve O₂ saturation of 95%).

4. Make frequent (every 1 to 2 hours) objective assessments of the response to therapy until definite, sustained improvement is documented.

5. Admit patients who do not respond well after 4 to 6 hours to a setting of high surveillance and care.

Bronchodilators but not inhaled glucocorticosteroids are the therapeutic mainstay for COPD patients.4 They include anticholinergics, beta agonists, and theophylline. β2 agonists and anticholinergics are available in short-acting and long-acting inhaled formulations. The scheme of the treatment for COPD is shown in Figure 3. Table 2 shows commonly used drugs used in COPD in Japan. In COPD, the order of bronchodilators is inhaled anticholinergics, inhaled β2-agonists and theophylline. Most bronchodilators are administered by inhalation, orally, or intravenously. A metered dose inhaler (MDI), dry powder inhaler (DPI), or nebulizer can be used to deliver a bronchodilator medication by inhalation. Moreover, it is known that the long acting anticholinergics and long acting β2-agonists work well in COPD.4, 5 Combination therapy using inhaled glucocorticosteroids plus long-acting β2 agonists significantly improves some outcomes compared to placebo, long-acting β2 agonists alone, or inhaled glucocorticosteroids alone.6

GOLD defines an exacerbation of COPD as an acute increase in symptoms beyond normal day-to-day variation.4 An exacerbation of COPD includes one or more of the following symptoms: dyspnea increases, cough increases in frequency and severity, and sputum production increases in volume and/or changes character. The major components of managing an acute exacerbation of COPD include inhaled short-acting bronchodilators (beta adrenergic agonists and anticholinergic agents), glucocorticosteroids, and antibiotics.

Increase dose and/or frequency of existing short-acting bronchodilator therapy, preferably inhaled SABA such as salbutamol and procaterol in Japan. If not already used, add anticholinergic agents until symptoms improve. For example, inhaled short-acting anticholinergic agents (e.g. ipratropium bromide) can be used with SABAs to treat acute exacerbations of COPD.

Previous studies have shown that systemic glucocorticoid therapy improves lung function and treatment success, while reducing the length of hospital stay.7, 8 The optimal dose of systemic glucocorticosteroids for treating a COPD exacerbation is still unknown. If baseline FEV1 <50% predicted, prednisone (30 to 40 mg orally, once daily) should be given for 7 to 10 days to the bronchodilator regimen.4 Methylprednisolone (60 to 125 mg, 2 to 4 times daily) are also used intravenously. It is of note that high doses of systemic glucocorticosteroids may increase the risk of side effects. Lower doses (e.g. 30 to 40 mg of prednisone) may be equally effective and safe.4

Antibiotics should be given to patients. Bacterial infections appear to trigger one-third to one-half of COPD exacerbations. Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae are the bacteria most frequently isolated bronchoscopically from patients having an exacerbation of COPD.9-11 Therefore, antibiotics including amoxicillin-clavulanate, azithromycin, cefpodoxime, cefprozil, cefuroxime, loracarbef, and the fluoroquinolones are commonly used against H. influenzae, M. catarrhalis, and S. pneumoniae for outpatients. For hospitalized patients with risk factors for Pseudomonas, antibiotic choices include levofloxacin, cefepime, ceftazidime, and piperacillin-tazobactam. Hospitalized patients without risk factors for Pseudomonas can be treated with a respiratory fluoroquinolone (levofloxacin, moxifloxacin) or a third-generation cephalosporin (ceftriaxone or cefotaxime).12

REFERENCES

1
Global Initiative for Asthma (GINA). Global Strategy for Asthma Management and Preventation. Revised 2008. Available at: http://www.ginasthma.com.

2
Haahtela T, Jarvinen M, Kava T et al. Comparison of a beta 2-agonist, terbutaline, with an inhaled corticosteroid, budesonide, in newly detected asthma. N Engl J Med 1991; 325: 388-92.
 

3
Emerman CL, Cydulka RK. A randomized comparison of 100-mg vs 500-mg dose of methylprednisolone in the treatment of acute asthma. Chest 1995; 107: 1559-63.
 

4
Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease, NHLBI/WHO Workshop Report. Revised 2006. Available at: http://www.Goldcopd.Com. Accessed November 25, 2006.

5
Tashkin DP, Celli B, Senn S et al. A 4-year trial of tiotropium in chronic obstructive pulmonary disease. N Engl J Med 2008; 359: 1543-54.
 

6
Calverley PM, Anderson JA, Celli B et al. Salmeterol and fluticasone propionate and survival in chronic obstructive pulmonary disease. N Engl J Med 2007; 356: 775-89.
 

7
Niewoehner DE, Erbland ML, Deupree RH et al. Effect of systemic glucocorticoids on exacerbations of chronic obstructive pulmonary disease. Department of veterans affairs cooperative study group. N Engl J Med 1999; 340: 1941-7.
 

8
Quon BS, Gan WQ, Sin DD. Contemporary management of acute exacerbations of COPD: A systematic review and metaanalysis. Chest 2008; 133: 756-66.

9
Bartlett JG. Diagnostic accuracy of transtracheal aspiration bacteriologic studies. Am Rev Respir Dis 1977; 115: 777-82.
 

10
Soler N, Torres A, Ewig S et al. Bronchial microbial patterns in severe exacerbations of chronic obstructive pulmonary disease (COPD) requiring mechanical ventilation. Am J Respir Crit Care Med 1998; 157: 1498-505.
 

11
Bandi V, Apicella MA, Mason E et al. Nontypeable haemophilus influenzae in the lower respiratory tract of patients with chronic bronchitis. Am J Respir Crit Care Med 2001; 164: 2114-9.
 

12
Stoller JK. Clinical practice. Acute exacerbations of chronic obstructive pulmonary disease. N Engl J Med 2002; 346: 988-94.