REVIEW ARTICLE
Management of acute asthma exacerbations Christine Franzese, MD, FAAOA
Background: Acute asthma exacerbations are common events in the lives of asthmatics, and even the best-managed asthma patients will have acute asthma exacerbations. There are different levels of severity of exacerbations with corresponding management strategies the physician can use to treat acute events. These strategies, including some adjunctive therapies, are reviewed in this article. Methods: A review of the English-language scientific literature was performed regarding management of acute asthma exacerbations, focusing of published guidelines, meta-analyses, and database reviews. Results: Symptoms of exacerbations are reviewed with attention to determining the severity of the exacerbation and the place of management, either at home or in a more acute care seing. Medical therapies for the treatment of each
A
sthma exacerbations may happen even in the bestcontrolled asthmatic patients. These events are common in the lives of asthmatic patients and can occur with any level of severity of asthma. These events pose the greatest threat to the lives of patients with asthma and the largest burden of healthcare-related treatment costs.1 Advances in medical knowledge have led to the identification of risk factors for asthma exacerbations and the implementation of written action plans to manage patients. Improvements in medical therapy have improved outpatient management and have prevented worsening of asthma symptoms.2 However, patients will still experience these adverse events, and patient education with early communication to the physician is key to early recognition and treatment. Determination of the severity of the acute
Department of Otolaryngology, Eastern Virginia School of Medicine, Norfolk, VA Correspondence to: Christine Franzese, MD, FAAOA, Eastern Virginia School of Medicine, Department of Otolaryngology, 600 Gresham Drive, Suite 1100, Norfolk, VA 23507; e-mail: [email protected] Potential conflict of interest: Greer, Advisory Board; Merck, Speakers Bureau. Received: 31 March 2015; Revised: 17 April 2015; Accepted: 20 April 2015 DOI: 10.1002/alr.21554 View this article online at wileyonlinelibrary.com.
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severity level are reviewed as to their effectiveness. Postexacerbation care is also discussed. Conclusion: Asthma exacerbations will happen and both the provider and patient need to be educated on how to manage these occurrences. Whether the patient is managed at home or in a hospital seing will be determined by the level of severity. Regardless of the medical therapies employed, continued focus should be on further prevenC 2015 ARS-AAOA, LLC. tion of additional exacerbations.
Key Words: asthma severity; wrien action plan; asthma treatment; oral corticosteroids; asthma patient education How to Cite this Article: Franzese C. Management of acute asthma exacerbations. Int Forum Allergy Rhinol. 2015;5:S51–S56.
exacerbation can aid the provider in deciding where to manage the patient and what treatment options to use. Once the patient has weathered the event at home or upon discharge from the emergency room (ER) or hospital setting, both the physician and the patient must revisit the written action plan to determine where adjustments need to be made. This article reviews the symptoms of acute asthma exacerbations and provide an overview of the levels of severity of exacerbations, determination of location of patient management, and therapeutic options available to adults and most children. Infants with asthma require specialized care and, as such, are beyond the scope of this article, as are additional intensive treatments available, a comprehensive review of all management strategies, and ventilator management.
Recognition of symptoms and determination of severity Asthma exacerbations are acute or subacute episodes of symptoms that can be graded as mild to severe. Subjective symptoms of exacerbations include progressively worsening shortness of breath, cough, wheezing, and chest tightness—or some combination of these symptoms.3 Signs
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of an exacerbation include agitation, increased respiratory rate, increased pulse rate, and decreased lung function as measured by forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), partial pressure of O2 in the blood (PaO2 ), partial pressure of CO2 in the blood (pCO2 ), and arterial oxygen saturation (SaO2 ).4 Objective measurements such as decreased expiratory airflow or oxygenation more consistently reflect the level of severity than patient symptoms.3, 4 Determination of severity of an acute exacerbation generally occurs in 2 parts, with the first part actually completed by the patient. If the patient has a written action plan and is educated in the use of quick-relief medications, the patient will have guidance in determining the severity of the exacerbation. Asthma action plans generally list symptoms and personal best PEF percentages that guide the patient in deciding if he/she falls into 1 of 3 categories. Each category has instructions from the physician on what course of action the patient should take if they become symptomatic. In general, a patient does not require intervention unless the PEF falls below 80%. When the PEF falls between 50 and 79%, the patient should use quick-relief medications carefully, monitor his/her response, and contact the physician if symptoms do not improve or worsen. If PEF falls below 50%, the patient should seek immediate medical care. If the patient does not have a written asthma action plan, the physician is still relying on the patient to make an assessment of any symptoms, use medications as instructed, and seek medical assistance if needed. This step will merely take place generally without any written guidance and the physician relies on the patient to recognize his/her symptoms to make the correct determination. It is important to note that lack of a written action plan and difficulty with patient perception of the severity of symptoms are 2 risk factors in asthma-related deaths.3 If the patient seeks medical attention then the second part of the determination of severity takes place. In the urgent or emergency care setting, the level of severity of a patient’s asthma exacerbation can be assessed based up patient symptoms, physical examination findings, and objective assessments of lung function. There is no single parameter that best identifies the severity of an event, so generally a combination of symptoms, signs, and measurements are used; however, lung function is often used and included in criteria for definitions of severity. In adults, if PEF or FEV1 can be obtained, this is useful in categorizing the level of severity and guiding therapy and it is recommended they be obtained at presentation and again in intervals of 30 to 60 minutes.5 However, adults with severe exacerbations may be unable to perform these tests and instituting therapy should not be delayed in these situations. In patients under the age of 5 years or any child unable to perform PEF, assessment of the use of accessory respiratory muscles, presence of chest wall retractions, tachypnea greater than 60 breaths per minute, cyanosis, and the presence of both inspiratory and expiratory wheezing should be included in the determination of severity level.5
Figure 1 outlines the levels of severity when assessing a patient in an urgent care or ER setting.3 Certain risk factors and predictors can be used by the provider to decide the need for hospitalization or admission to the intensive care unit (ICU). Pulse oximetry values of less than 92% on room air 1 hour after beginning standard treatment is a strong predictor for the need for hospitalization.3 Pulse oximetry in children is very helpful when FEV1 or PEF values cannot be obtained. Risks for asthma-related death such as previous severe exacerbation, 2 or more hospitalizations in the past year for asthma or 1 in the past month, 2 or more ER visits in the last year for asthma or 1 in the past month, and using more than 2 canisters of a short-acting beta agonist (SABA) in 1 month, also need to be considered.
Place of treatment Determining the level of severity of an acute exacerbation is important because it will determine where the treatment takes place and often what medical therapies are used. The treatment for asthma exacerbations can occur in the patient’s home, in the physician’s office, in the ER, or in the inpatient or ICU setting. For mild events, the place of treatment will generally be at home with the patient using quick-relief medications, such as a SABA. It is vital to educate the patient on the importance of mentioning exacerbations managed at home to the physician so that needed adjustments to the written action plan can take place to prevent worsening of any future exacerbations. Moderate events can often be managed in the office setting or in the ER with more severe episodes requiring hospitalization as an inpatient or in the ICU. Regardless of the setting of treatment or severity of the event, early intervention is the key to a successful management strategy and this requires patient education on initiating therapy in the home at the earliest signs of worsening asthma.
Outpatient management strategies This section and the next cover interventions that can be used in the outpatient and inpatient setting. Because pharmacology of these medications is discussed in Section 8 of this primer, it will not be repeated. However, medication dosages that are outside the standard or common practice dosages are listed, as well as those for unusual medications. These interventions cover most adults and children, but do not include infants. Outpatient management strategies include the use of quick-relief medications, such as albuterol, pirbuterol, and levoalbuterol, and possibly the addition of oral corticosteroids. The cornerstone of treatment for all asthma exacerbations is the use of a SABA either as a metered dose inhaler (MDI) or in a nebulizer.3, 6 Up to 2 treatments of 2 to 6 inhalations of a SABA roughly 20 minutes apart may be used by patients having acute exacerbations whose PEF falls between 50% and 79% of their personal best. The treatments
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FIGURE 1. Classifying severity of asthma exacerbations in the urgent or emergency care setting. Source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services.
should be followed by a reassessment of PEF and symptoms. If patients do not achieve a PEF of 80% or greater after such measures, they should contact their physician for more instructions that day. If the PEF worsens or falls below 50%, patients should seek emergency care while contacting their physician. A Cochran review has shown that administration using a hand-held MDI with a spacer device is at least equivalent to nebulized SABA in children older than 1 year (4 puffs per dose) and adults (6 puffs per dose).7 There is no demonstrable difference in terms of safety or effectiveness between levalbuterol and albuterol.8 For patients whose PEF does not improve to 80% or greater, a short burst of oral steroids can be added. A short course of oral prednisolone at the onset of worsening symptoms produced a modest benefit in terms of decreased symptoms, health resource use, and absence from school in 1 study of children 5 to 12 years old with frequent acute exacerbations.9 Patient-initiated or parent-initiated increases in the dosage of inhaled corticosteroids (ICS) have been proposed to help with deteriorating asthma symptoms in children, although the data is not sufficient for a recommendation.10 In adults, no benefit has been shown to increasing or doubling the dosage of ICS in those patients already on ICS in reducing the severity or preventing progression of exacerbations, as a meta-analysis of data
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from more than 1200 adults demonstrates that increasing the dosage does not reduce the risk of a subsequent asthma exacerbation requiring oral corticosteroids.3, 11 For children with intermittent asthma, montelukast may be another option. A randomized controlled trial of parent-initiated montelukast in children with intermittent asthma, montelukast resulted in a reduction in unscheduled healthcare visits and time lost from work and school or childcare.12
ER and inpatient management strategies While assessing a patient to determine the severity of an acute exacerbation, treatment can and should be initiated with the goals of relieving/reversing airflow obstruction, correcting any hypoxemia, and monitoring the response to treatment. Treatment should not be withheld until after a history and physical examination is completed because early intervention is the key in management. A brief history and physical can be performed while initial treatment is underway; afterwards in assessing response to therapy, a more thorough history and physical can be performed if the patient is stabilized. Once a brief initial assessment is done, the severity level can be determined and recommend therapies instituted, as outlined in Figure 2.3
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FIGURE 2. Management of asthma exacerbations: emergency department and hospital-based care. Source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services.
Initial treatment consists of a SABA with oxygen therapy. Oxygen therapy should be instituted to keep oxygen saturations at or above 90% in most patients or 95% in pregnant women or those with coronary artery disease.3 Oxygen, like SABA therapy, should be initiated as soon as possible and ideally in the prehospital setting.5 Continuous beta2 agonist administration has been shown to improve pulmonary function measurements and reduce hospital
admission with no notable differences in pulse, blood pressure, or tremor for those patients with severe exacerbations not responding to intermittent SABA treatement.13 The use of high-dose albuterol (7.5 mg via nebulizer every 20 minutes for 3 doses)14 and intravenous beta2 agonists does not appear to be beneficial and is not recommended.15 For moderate to severe exacerbations that do not respond to initial SABA therapy, corticosteroids should be
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initiated whether the patient will be admitted to the hospital or discharged. Oral prednisone can be initiated in the ER and has been demonstrated to be equivalent to intravenous methylprednisolone.3 In the inpatient setting, oral steroids should be continued because systemic corticosteroids have demonstrated benefit in reducing the length of asthma exacerbations. Intravenous steroids have not demonstrated superior efficacy and are not recommended over oral steroids, unless the oral route cannot be effectively utilized.3 For severe exacerbations, multiple high doses of ipratropium bromide (0.5 mg nebulizer solution or 8 puffs by MDI in adults; 0.25 to 0.5 mg nebulizer solution or 4 to 8 puffs by MDI in children) in combination with a SABA produces additional bronchodilation, resulting in fewer hospital admissions.3, 16 However, studies have failed to demonstrate that continued use of ipratropium bromide has any benefit in the inpatient setting or as initial therapy in adults in the outpatient setting with mild to moderate exacerbations. For severe exacerbations not responsive to other therapies where symptoms are continuing to worsen toward impending respiratory failure, 2 additional adjuvant therapies have been proposed to possibly avoid intubation. These therapies should not be used to delay intubation once the judgment to intubate the patient has been made. Heliox, a helium and oxygen mixture, which has a lower density than oxygen, could improve gas exchange; several studies have examined the use of heliox-driven albuterol nebulization. These studies were all small and demonstrated conflicting results, thus heliox-driven albuterol nebulization remains a potential adjuvant therapy.17 Intravenous magnesium is a second adjuvant option. Two meta-analyses of studies demonstrated that intravenous magnesium sulfate (2 g in adults and 25 to 75 mg/kg up to 2 g in children) added to conventional therapy reduced hospitalization rates in ER patients who present with severe asthma exacerbations. The treatment has no therapeutic value in patients with less severe exacerbations.18, 19 Once the decision to intubate a patient is made, it should be carried out without delay by an experienced practitioner.
In general, orotracheal intubation with sedation and neuromuscular blockade are preferred for asthmatic patients in critical respiratory distress and the use of ketamine and propofol might be preferred over other sedative agents.5 Further management of the critically ill ICU asthmatic patient is beyond the scope of this article.
Post-exacerbation management When a patient’s FEV1 has reached 70% or greater than personal best after treatment, discharge from the ER or the hospital can be considered. At this point, appropriate medications and patient education are extremely important in preventing a relapse and return to the ER or readmission. Patients must be educated to understand that, for an acute moderate exacerbation, it will take roughly 1 to 2 days for the patient to recover, and more severe exacerbations may take 3 to 4 days. If a patient is discharged from the ER or hospital, oral corticosteroids should be used for 5 to 10 days in a non-tapering high-dose course (prednisone 50 to 100 mg per day in adults) because corticosteroids have shown to decrease relapse of asthma symptoms, future hospitalizations, and use of short-acting beta2 agonists.20, 21 For children ages 2 to 15 years, 3 days of prednisone 1 mg/kg have been shown to be equal in efficacy to 5 days for complete resolution of symptoms within 1 week. As discussed in Section 9 of this primer, physicians will need to “step up” the patient’s medications to a higher level several days to weeks after discharge and the patient should leave the hospital or ER with a new or adjusted written action plan with expectations to follow up in the physician’s office in 1 to 4 weeks.3 Post-exacerbation communication between the patient and the physician is very important to prevent future worsening of asthma symptoms and exacerbations. Scheduled dosing of SABA should continue until the patients symptoms and PEF return to baseline. If exacerbations are managed at home, the patient and physician must review the event(s) and decide what changes, if any, will be made to the written action plan.
References 1.
2.
3.
4.
5.
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Barnett SB, Nurmagambetov TA. Costs of asthma in the United States: 2002-2007. J Allergy Clin Immunol. 2011;127:145–152. Pollart SM, Compton RM, Eldward KS. Management of acute asthma exacerbations. Am Fam Physician. 2011;84:40–47. U.S. Department of Health and Human Services, National Institute of Health, National Heart, Lung, and Blood Institute. Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma; 2007. http://www.nhlbi.nih.gov/guidelines/asthma/ asthgdln.pdf. Accessed May 4, 2015. Schatz M, Kazzi AAN, Brenner B, Camargo CA Jr. Task Force Report: Supplemental Recommendations for the Management and Follow-up of Asthma Exacerbations. Proc Am Thorac Soc. 2009;6: 353-356. Camargo CA Jr, Rachelefsky G, Schatz M. Managing asthma exacerbations in the emergency department: summary of the National Asthma Education and Prevention Program Expert Panel Report 3 guidelines for the management of asthma exacerbations. J Allergy Clin Immunol. 2009;124(2 Suppl):S5–S14.
6.
Newhouse MT, Dolovich MB. Control of asthma by aerosols. N Engl J Med. 1986;315:870–874. 7. Cates CJ, Crilly JA, Rowe BH. Holding chambers (spacers) versus nebulisers for beta-agonist treatment of acute asthma. Cochrane Database Syst Rev. 2006;(2):CD000052. 8. Qureshi F, Zaritsky A, Welch C, Meadows T, Burke BL. Clinical efficacy of racemic albuterol versus levalbuterol for the treatment of acute pediatric asthma. Ann Emerg Med. 2005;46:29–36. 9. Rice-McDonald G, Bowler S, Staines G, Mitchell C. Doubling daily inhaled corticosteroid dose is ineffective in mild to moderately severe attacks of asthma in adults. Intern Med J. 2005;35:693–698. 10. Vuillermin PJ, Robertson CF, Carlin JB, Brennan SL, Biscan MI, South M. Parent initiated prednisolone for acute asthma in children of school age: randomised controlled crossover trial. BMJ. 2010;340:c843. 11. Quon BS, Fitzgerald JM, Lemi`ere C, Shahidi N, Ducharme FM. Increased versus stable doses of inhaled corticosteroids for exacerbations of chronic asthma in adults and children. Cochrane Database Syst Rev. 2010;(10):CD007524.
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12. Robertson CF, Price D, Henry R, et al. Short-course montelukast for intermittent asthma in children: a randomized controlled trial. Am J Respir Crit Care Med. 2007;175:323–329. 13. Camargo CA Jr, Spooner CH, Rowe BH. Continuous versus intermittent beta-agonists in the treatment of acute asthma. Cochrane Database Syst Rev. 2003;(4):CD001115. 14. Emerman CL, Cydulka RK, McFadden ER. Comparison of 2.5 vs 7.5 mg of inhaled albuterol in the treatment of acute asthma. Chest. 1999;115:92-96. 15. Travers A, Jones AP, Kelly K, Barker SJ, Camargo CA, Rowe BH. Intravenous beta2-agonists for acute asthma in the emergency department. Cochrane Database Syst Rev. 2001;(2):CD002988. 16. Rodrigo GJ, Castro-Rodriguez JA. Anticholinergics in the treatment of children and adults with acute asthma: a systematic review with meta-analysis. Thorax. 2005;60:740–746. [Erratum in: Thorax. 2006;61:274 and Thorax. 2006;61:458.] 17. Rodrigo G, Pollack C, Rodrigo C, Rowe BH. Heliox for nonintubated acute asthma patients. Cochrane Database Syst Rev. 2006;(4):CD002884.
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18. Cheuk DK, Chau TC, Lee SL. A meta-analysis on intravenous magnesium sulphate for treating acute asthma. Arch Dis Child. 2005;90:74–77. 19. Rowe BH, Bretzlaff JA, Bourdon C, Bota GW, Camargo CA Jr. Intravenous magnesium sulfate treatment for acute asthma in the emergency department:
a systematic review of the literature. Ann Emerg Med. 2000;36:181–190. 20. Rowe BH, Spooner CH, Ducharme FM, Bretzlaff JA, Bota GW. Corticosteroids for preventing relapse following acute exacerbations of asthma. Cochrane Database Syst Rev. 2007;(3):CD000195.
21. Krishnan JA, Davis SQ, Naureckas ET, Gibson P, Rowe BH. An umbrella review: corticosteroid therapy for adults with acute asthma. Am J Med. 2009;122:977–991.
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Management of acute asthma exacerbations Christine Franzese, MD, FAAOA
Background: Acute asthma exacerbations are common events in the lives of asthmatics, and even the best-managed asthma patients will have acute asthma exacerbations. There are different levels of severity of exacerbations with corresponding management strategies the physician can use to treat acute events. These strategies, including some adjunctive therapies, are reviewed in this article. Methods: A review of the English-language scientific literature was performed regarding management of acute asthma exacerbations, focusing of published guidelines, meta-analyses, and database reviews. Results: Symptoms of exacerbations are reviewed with attention to determining the severity of the exacerbation and the place of management, either at home or in a more acute care seing. Medical therapies for the treatment of each
A
sthma exacerbations may happen even in the bestcontrolled asthmatic patients. These events are common in the lives of asthmatic patients and can occur with any level of severity of asthma. These events pose the greatest threat to the lives of patients with asthma and the largest burden of healthcare-related treatment costs.1 Advances in medical knowledge have led to the identification of risk factors for asthma exacerbations and the implementation of written action plans to manage patients. Improvements in medical therapy have improved outpatient management and have prevented worsening of asthma symptoms.2 However, patients will still experience these adverse events, and patient education with early communication to the physician is key to early recognition and treatment. Determination of the severity of the acute
Department of Otolaryngology, Eastern Virginia School of Medicine, Norfolk, VA Correspondence to: Christine Franzese, MD, FAAOA, Eastern Virginia School of Medicine, Department of Otolaryngology, 600 Gresham Drive, Suite 1100, Norfolk, VA 23507; e-mail: [email protected] Potential conflict of interest: Greer, Advisory Board; Merck, Speakers Bureau. Received: 31 March 2015; Revised: 17 April 2015; Accepted: 20 April 2015 DOI: 10.1002/alr.21554 View this article online at wileyonlinelibrary.com.
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severity level are reviewed as to their effectiveness. Postexacerbation care is also discussed. Conclusion: Asthma exacerbations will happen and both the provider and patient need to be educated on how to manage these occurrences. Whether the patient is managed at home or in a hospital seing will be determined by the level of severity. Regardless of the medical therapies employed, continued focus should be on further prevenC 2015 ARS-AAOA, LLC. tion of additional exacerbations.
Key Words: asthma severity; wrien action plan; asthma treatment; oral corticosteroids; asthma patient education How to Cite this Article: Franzese C. Management of acute asthma exacerbations. Int Forum Allergy Rhinol. 2015;5:S51–S56.
exacerbation can aid the provider in deciding where to manage the patient and what treatment options to use. Once the patient has weathered the event at home or upon discharge from the emergency room (ER) or hospital setting, both the physician and the patient must revisit the written action plan to determine where adjustments need to be made. This article reviews the symptoms of acute asthma exacerbations and provide an overview of the levels of severity of exacerbations, determination of location of patient management, and therapeutic options available to adults and most children. Infants with asthma require specialized care and, as such, are beyond the scope of this article, as are additional intensive treatments available, a comprehensive review of all management strategies, and ventilator management.
Recognition of symptoms and determination of severity Asthma exacerbations are acute or subacute episodes of symptoms that can be graded as mild to severe. Subjective symptoms of exacerbations include progressively worsening shortness of breath, cough, wheezing, and chest tightness—or some combination of these symptoms.3 Signs
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of an exacerbation include agitation, increased respiratory rate, increased pulse rate, and decreased lung function as measured by forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), partial pressure of O2 in the blood (PaO2 ), partial pressure of CO2 in the blood (pCO2 ), and arterial oxygen saturation (SaO2 ).4 Objective measurements such as decreased expiratory airflow or oxygenation more consistently reflect the level of severity than patient symptoms.3, 4 Determination of severity of an acute exacerbation generally occurs in 2 parts, with the first part actually completed by the patient. If the patient has a written action plan and is educated in the use of quick-relief medications, the patient will have guidance in determining the severity of the exacerbation. Asthma action plans generally list symptoms and personal best PEF percentages that guide the patient in deciding if he/she falls into 1 of 3 categories. Each category has instructions from the physician on what course of action the patient should take if they become symptomatic. In general, a patient does not require intervention unless the PEF falls below 80%. When the PEF falls between 50 and 79%, the patient should use quick-relief medications carefully, monitor his/her response, and contact the physician if symptoms do not improve or worsen. If PEF falls below 50%, the patient should seek immediate medical care. If the patient does not have a written asthma action plan, the physician is still relying on the patient to make an assessment of any symptoms, use medications as instructed, and seek medical assistance if needed. This step will merely take place generally without any written guidance and the physician relies on the patient to recognize his/her symptoms to make the correct determination. It is important to note that lack of a written action plan and difficulty with patient perception of the severity of symptoms are 2 risk factors in asthma-related deaths.3 If the patient seeks medical attention then the second part of the determination of severity takes place. In the urgent or emergency care setting, the level of severity of a patient’s asthma exacerbation can be assessed based up patient symptoms, physical examination findings, and objective assessments of lung function. There is no single parameter that best identifies the severity of an event, so generally a combination of symptoms, signs, and measurements are used; however, lung function is often used and included in criteria for definitions of severity. In adults, if PEF or FEV1 can be obtained, this is useful in categorizing the level of severity and guiding therapy and it is recommended they be obtained at presentation and again in intervals of 30 to 60 minutes.5 However, adults with severe exacerbations may be unable to perform these tests and instituting therapy should not be delayed in these situations. In patients under the age of 5 years or any child unable to perform PEF, assessment of the use of accessory respiratory muscles, presence of chest wall retractions, tachypnea greater than 60 breaths per minute, cyanosis, and the presence of both inspiratory and expiratory wheezing should be included in the determination of severity level.5
Figure 1 outlines the levels of severity when assessing a patient in an urgent care or ER setting.3 Certain risk factors and predictors can be used by the provider to decide the need for hospitalization or admission to the intensive care unit (ICU). Pulse oximetry values of less than 92% on room air 1 hour after beginning standard treatment is a strong predictor for the need for hospitalization.3 Pulse oximetry in children is very helpful when FEV1 or PEF values cannot be obtained. Risks for asthma-related death such as previous severe exacerbation, 2 or more hospitalizations in the past year for asthma or 1 in the past month, 2 or more ER visits in the last year for asthma or 1 in the past month, and using more than 2 canisters of a short-acting beta agonist (SABA) in 1 month, also need to be considered.
Place of treatment Determining the level of severity of an acute exacerbation is important because it will determine where the treatment takes place and often what medical therapies are used. The treatment for asthma exacerbations can occur in the patient’s home, in the physician’s office, in the ER, or in the inpatient or ICU setting. For mild events, the place of treatment will generally be at home with the patient using quick-relief medications, such as a SABA. It is vital to educate the patient on the importance of mentioning exacerbations managed at home to the physician so that needed adjustments to the written action plan can take place to prevent worsening of any future exacerbations. Moderate events can often be managed in the office setting or in the ER with more severe episodes requiring hospitalization as an inpatient or in the ICU. Regardless of the setting of treatment or severity of the event, early intervention is the key to a successful management strategy and this requires patient education on initiating therapy in the home at the earliest signs of worsening asthma.
Outpatient management strategies This section and the next cover interventions that can be used in the outpatient and inpatient setting. Because pharmacology of these medications is discussed in Section 8 of this primer, it will not be repeated. However, medication dosages that are outside the standard or common practice dosages are listed, as well as those for unusual medications. These interventions cover most adults and children, but do not include infants. Outpatient management strategies include the use of quick-relief medications, such as albuterol, pirbuterol, and levoalbuterol, and possibly the addition of oral corticosteroids. The cornerstone of treatment for all asthma exacerbations is the use of a SABA either as a metered dose inhaler (MDI) or in a nebulizer.3, 6 Up to 2 treatments of 2 to 6 inhalations of a SABA roughly 20 minutes apart may be used by patients having acute exacerbations whose PEF falls between 50% and 79% of their personal best. The treatments
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FIGURE 1. Classifying severity of asthma exacerbations in the urgent or emergency care setting. Source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services.
should be followed by a reassessment of PEF and symptoms. If patients do not achieve a PEF of 80% or greater after such measures, they should contact their physician for more instructions that day. If the PEF worsens or falls below 50%, patients should seek emergency care while contacting their physician. A Cochran review has shown that administration using a hand-held MDI with a spacer device is at least equivalent to nebulized SABA in children older than 1 year (4 puffs per dose) and adults (6 puffs per dose).7 There is no demonstrable difference in terms of safety or effectiveness between levalbuterol and albuterol.8 For patients whose PEF does not improve to 80% or greater, a short burst of oral steroids can be added. A short course of oral prednisolone at the onset of worsening symptoms produced a modest benefit in terms of decreased symptoms, health resource use, and absence from school in 1 study of children 5 to 12 years old with frequent acute exacerbations.9 Patient-initiated or parent-initiated increases in the dosage of inhaled corticosteroids (ICS) have been proposed to help with deteriorating asthma symptoms in children, although the data is not sufficient for a recommendation.10 In adults, no benefit has been shown to increasing or doubling the dosage of ICS in those patients already on ICS in reducing the severity or preventing progression of exacerbations, as a meta-analysis of data
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from more than 1200 adults demonstrates that increasing the dosage does not reduce the risk of a subsequent asthma exacerbation requiring oral corticosteroids.3, 11 For children with intermittent asthma, montelukast may be another option. A randomized controlled trial of parent-initiated montelukast in children with intermittent asthma, montelukast resulted in a reduction in unscheduled healthcare visits and time lost from work and school or childcare.12
ER and inpatient management strategies While assessing a patient to determine the severity of an acute exacerbation, treatment can and should be initiated with the goals of relieving/reversing airflow obstruction, correcting any hypoxemia, and monitoring the response to treatment. Treatment should not be withheld until after a history and physical examination is completed because early intervention is the key in management. A brief history and physical can be performed while initial treatment is underway; afterwards in assessing response to therapy, a more thorough history and physical can be performed if the patient is stabilized. Once a brief initial assessment is done, the severity level can be determined and recommend therapies instituted, as outlined in Figure 2.3
Franzese et al.
FIGURE 2. Management of asthma exacerbations: emergency department and hospital-based care. Source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services.
Initial treatment consists of a SABA with oxygen therapy. Oxygen therapy should be instituted to keep oxygen saturations at or above 90% in most patients or 95% in pregnant women or those with coronary artery disease.3 Oxygen, like SABA therapy, should be initiated as soon as possible and ideally in the prehospital setting.5 Continuous beta2 agonist administration has been shown to improve pulmonary function measurements and reduce hospital
admission with no notable differences in pulse, blood pressure, or tremor for those patients with severe exacerbations not responding to intermittent SABA treatement.13 The use of high-dose albuterol (7.5 mg via nebulizer every 20 minutes for 3 doses)14 and intravenous beta2 agonists does not appear to be beneficial and is not recommended.15 For moderate to severe exacerbations that do not respond to initial SABA therapy, corticosteroids should be
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initiated whether the patient will be admitted to the hospital or discharged. Oral prednisone can be initiated in the ER and has been demonstrated to be equivalent to intravenous methylprednisolone.3 In the inpatient setting, oral steroids should be continued because systemic corticosteroids have demonstrated benefit in reducing the length of asthma exacerbations. Intravenous steroids have not demonstrated superior efficacy and are not recommended over oral steroids, unless the oral route cannot be effectively utilized.3 For severe exacerbations, multiple high doses of ipratropium bromide (0.5 mg nebulizer solution or 8 puffs by MDI in adults; 0.25 to 0.5 mg nebulizer solution or 4 to 8 puffs by MDI in children) in combination with a SABA produces additional bronchodilation, resulting in fewer hospital admissions.3, 16 However, studies have failed to demonstrate that continued use of ipratropium bromide has any benefit in the inpatient setting or as initial therapy in adults in the outpatient setting with mild to moderate exacerbations. For severe exacerbations not responsive to other therapies where symptoms are continuing to worsen toward impending respiratory failure, 2 additional adjuvant therapies have been proposed to possibly avoid intubation. These therapies should not be used to delay intubation once the judgment to intubate the patient has been made. Heliox, a helium and oxygen mixture, which has a lower density than oxygen, could improve gas exchange; several studies have examined the use of heliox-driven albuterol nebulization. These studies were all small and demonstrated conflicting results, thus heliox-driven albuterol nebulization remains a potential adjuvant therapy.17 Intravenous magnesium is a second adjuvant option. Two meta-analyses of studies demonstrated that intravenous magnesium sulfate (2 g in adults and 25 to 75 mg/kg up to 2 g in children) added to conventional therapy reduced hospitalization rates in ER patients who present with severe asthma exacerbations. The treatment has no therapeutic value in patients with less severe exacerbations.18, 19 Once the decision to intubate a patient is made, it should be carried out without delay by an experienced practitioner.
In general, orotracheal intubation with sedation and neuromuscular blockade are preferred for asthmatic patients in critical respiratory distress and the use of ketamine and propofol might be preferred over other sedative agents.5 Further management of the critically ill ICU asthmatic patient is beyond the scope of this article.
Post-exacerbation management When a patient’s FEV1 has reached 70% or greater than personal best after treatment, discharge from the ER or the hospital can be considered. At this point, appropriate medications and patient education are extremely important in preventing a relapse and return to the ER or readmission. Patients must be educated to understand that, for an acute moderate exacerbation, it will take roughly 1 to 2 days for the patient to recover, and more severe exacerbations may take 3 to 4 days. If a patient is discharged from the ER or hospital, oral corticosteroids should be used for 5 to 10 days in a non-tapering high-dose course (prednisone 50 to 100 mg per day in adults) because corticosteroids have shown to decrease relapse of asthma symptoms, future hospitalizations, and use of short-acting beta2 agonists.20, 21 For children ages 2 to 15 years, 3 days of prednisone 1 mg/kg have been shown to be equal in efficacy to 5 days for complete resolution of symptoms within 1 week. As discussed in Section 9 of this primer, physicians will need to “step up” the patient’s medications to a higher level several days to weeks after discharge and the patient should leave the hospital or ER with a new or adjusted written action plan with expectations to follow up in the physician’s office in 1 to 4 weeks.3 Post-exacerbation communication between the patient and the physician is very important to prevent future worsening of asthma symptoms and exacerbations. Scheduled dosing of SABA should continue until the patients symptoms and PEF return to baseline. If exacerbations are managed at home, the patient and physician must review the event(s) and decide what changes, if any, will be made to the written action plan.
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12. Robertson CF, Price D, Henry R, et al. Short-course montelukast for intermittent asthma in children: a randomized controlled trial. Am J Respir Crit Care Med. 2007;175:323–329. 13. Camargo CA Jr, Spooner CH, Rowe BH. Continuous versus intermittent beta-agonists in the treatment of acute asthma. Cochrane Database Syst Rev. 2003;(4):CD001115. 14. Emerman CL, Cydulka RK, McFadden ER. Comparison of 2.5 vs 7.5 mg of inhaled albuterol in the treatment of acute asthma. Chest. 1999;115:92-96. 15. Travers A, Jones AP, Kelly K, Barker SJ, Camargo CA, Rowe BH. Intravenous beta2-agonists for acute asthma in the emergency department. Cochrane Database Syst Rev. 2001;(2):CD002988. 16. Rodrigo GJ, Castro-Rodriguez JA. Anticholinergics in the treatment of children and adults with acute asthma: a systematic review with meta-analysis. Thorax. 2005;60:740–746. [Erratum in: Thorax. 2006;61:274 and Thorax. 2006;61:458.] 17. Rodrigo G, Pollack C, Rodrigo C, Rowe BH. Heliox for nonintubated acute asthma patients. Cochrane Database Syst Rev. 2006;(4):CD002884.
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