CLASSIFYING THE SEVERITY OF ASTHMA EXACERBATIONS INITIAL ASSESSMENT OF ASTHMA EXACERBATIONS IN THE ED

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1 Managing Asthma Exacerbations in the Emergency Department Summary of the National Asthma Eucation an Prevention Program Expert Panel Report 3 Guielines for the Management of Asthma Exacerbations Carlos A. Camargo, Jr. 1, Gary Rachelefsky 2, an Michael Schatz 3 1 Department of Emergency Meicine an Division of Rheumatology, Allergy an Immunology, Department of Meicine, Massachusetts General Hospital, Harvar Meical School, Boston, Massachusetts; 2 Executive Care Center for Asthma, Allergy, an Respiratory Diseases at the Geffen School of Meicine, University of California Los Angeles, Los Angeles, California; an 3 Department of Allergy, Kaiser Permanente Meical Center, San Diego, California Keywors: asthma exacerbation, emergency epartment, Expert Panel Report 3, acute asthma, respiratory failure This article summarizes the recommenations regaring the management of asthma exacerbations presente in the Expert Panel Report 3 (EPR3) (1). The evience supporting these recommenations can be foun in the report itself. All of the recommenations in this article are strong recommenations, unless inicate by the term conitional. Asthma exacerbations consist of acute or subacute episoes of progressively worsening shortness of breath, coughing, wheezing, an chest tightness or any combination thereof. These episoes iffer from poor asthma control in that iurnal variability in airflow, a key marker of poor asthma control, might not change uring an exacerbation (2). An important avance in the new National Asthma Eucation an Prevention Program (NAEPP) EPR3 guielines (1) is the creation of a chapter evote to the management of asthma exacerbations. Moreover, the new EPR3 guielines present ifferent spirometry cut points for assessing the severity of acute asthma (exacerbations) versus chronic asthma. These an other changes unerscore the istinction between acute an chronic asthma management. Two patient populations at particular risk uring an asthma exacerbation inclue patients with one or more risk factors for asthma-relate eath (Table 1) an infants, who are at greater risk for respiratory failure because of ifferences in lung anatomy an physiology. The assessment an treatment of young chilren pose unique challenges, but management of asthma exacerbations in oler chilren is generally similar to that in aults. Abbreviations use: ED, Emergency epartment; EMS, emergency meical services; EPR3, Expert Panel Report 3; MDI, metere-ose inhaler; PEF, peak expiratory flow; Sa O2, arterial oxygen saturation. This article is part of the Joint Task Force Report: Supplemental Recommenations for the Management an Follow-up of Asthma Exacerbations, an official workshop report of the American Acaemy of Allergy, Asthma an Immunology (AAAAI), the American Acaemy of Emergency Meicine (AAEM), an the American Thoracic Society (ATS). It was approve by the AAAAI Boar of Directors, January 16, 2008, the AAEM Boar of Directors, January 14, 2008, an the ATS Boar of Directors, March 13, The Joint Task Force Report is copublishe in the Journal of Allergy an Clinical Immunology, the Journal of Emergency Meicine, an the American Journal of Respiratory an Critical Care Meicine. Supporte through an unrestricte eucational grant to AAAAI an AAEM for publication an issemination costs from GlaxoSmithKline, which ha no input into the task force recommenations. Reprint requests: Not available. Ó 2009 American Acaemy of Allergy, Asthma & Immunology; the American Thoracic Society; an Elsevier Inc. Proc Am Thorac Soc Vol 6. pp , 2009 DOI: /pats.P09ST2 Internet aress: Early treatment of asthma exacerbations is the best strategy for management. Important elements of early treatment at the patient s home inclue a written asthma action plan; recognition of early signs an symptoms of worsening; appropriate intensification of therapy by increasing short-acting b-agonists an, in some cases, aing a short course of oral corticosterois; removal, or withrawal from an environmental factor contributing to the exacerbation; an prompt communication between the patient an clinician, seeking emergency care for severe manifestations, or both. Despite aherence to optimal chronic asthma care, it is increasingly recognize that some patients will require an urgent office visit or even an emergency epartment (ED) visit for further asthma care. CLASSIFYING THE SEVERITY OF ASTHMA EXACERBATIONS Symptoms of asthma exacerbations inclue breathlessness, coughing, wheezing, an chest tightness. The signs of asthma exacerbation inclue agitation, increase respiratory rate, increase pulse rate, an ecrease lung function as measure by FEV 1, peak expiratory flow (PEF), Pa O2,Pa CO2, an arterial oxygen saturation (Sa O2 ). The use of accessory muscles an the inability to talk in sentences or even in phrases might or might not be present, epening on the severity of the exacerbation. The severity of these symptoms an signs, along with the finings on functional lung assessment, are use to categorize asthma exacerbations as mil, moerate, severe, or lifethreatening (Table 2). The primary eterminant of severity is percent preicte FEV 1 or PEF. The exacerbation severity etermines treatment. Mil exacerbations can usually be manage at home, but more severe exacerbations might require treatment an monitoring in the ED or, in more serious cases, hospital amission. INITIAL ASSESSMENT OF ASTHMA EXACERBATIONS IN THE ED Severe exacerbations of asthma are potentially life-threatening an therefore require prompt care, close observation for eterioration, an frequent treatments. Serial measurement of lung function provies an objective measure of improvement. The NAEPP Expert Panel recommens that all clinicians treating asthmatic patients be prepare to treat an asthma exacerbation, recognize the signs an symptoms of severe an life-threatening exacerbations (Table 2), an be familiar with the risk factors for asthma-relate eath (Table 1). All patients presenting with a reporte asthma exacerbation shoul be evaluate an triage immeiately, with treatment institute

2 358 PROCEEDINGS OF THE AMERICAN THORACIC SOCIETY VOL TABLE 1. RISK FACTORS FOR DEATH FROM ASTHMA (ORIGINALLY PUBLISHED AS FIGURE 5-2A IN THE EPR3 [1]) Asthma history Previous severe exacerbation (e.g., intubation or ICU amission for asthma) Two or more hospitalizations for asthma in the past year Three or more ED visits for asthma in the past year Hospitalization or ED visit for asthma in the past month Using. 2 canisters of SABA per month Difficulty perceiving asthma symptoms or severity of exacerbations Other risk factors: lack of a written asthma action plan, sensitivity to Alternaria Social history Low socioeconomic status or inner-city resience Illicit rug use Major psychosocial problems Comorbiities Cariovascular isease Other chronic lung isease Chronic psychiatric isease Definition of abbreviations: ED 5 emergency epartment; ICU 5 intensive care unit; SABA, short-acting beta 2 -agonist. Sources: Abramson et al., 2001; Greenberger et al., 1993; Harie et al., 2002; Kallenbach et al., 1993; Kikuchi et al., 1994; O Hollaren et al., 1991; Rorigo an Rorigo, 1993; Strunk an Mrazek, 1986; Suissa et al., promptly on etermination of a moerate, severe, or lifethreatening exacerbation (Figure 1). While initial treatment is given, the clinician shoul obtain a brief history an perform a brief physical examination. The clinician shoul assess lung function (unless patient is in respiratory extremis) an obtain laboratory stuies only as neee. HISTORY The brief history shoul inclue the time of onset; any potential causes of the exacerbation; the severity of symptoms, especially compare with previous exacerbations; an the response to any treatment given before amission to the ED. In aition, the clinician shoul list all current meications an the time of the last ose (especially for asthma meications), along with the estimate number of previous unscheule office visits, ED visits, an hospitalizations for asthma, particularly within the preceing year. It is also important to note any previous episoes of serious respiratory insufficiency (e.g., involving loss of consciousness or intubation) an any other potentially complicating illness, particularly pulmonary or cariac isease or any isease that might be aggravate by systemic corticosteroi therapy, such as iabetes or hypertension. PHYSICAL EXAMINATION The objective of the brief physical examination is to assess both the severity of the exacerbation (Table 2) an overall patient status, incluing level of alertness, flui status, presence of cyanosis, respiratory istress, an wheezing, although wheezing can be an unreliable inicator of airway obstruction. Any possible complications, such as pneumonia, pneumothorax, or pneumomeiastinum, shoul be ientifie. Upper airway obstruction, such as that cause by foreign boies, epiglottitis, organic iseases of the larynx, vocal cor ysfunction, an extrinsic an intrinsic tracheal narrowing, shoul be rule out. Clues to the presence of upper airway obstruction as a cause of yspnea inclue ysphonia, inspiratory strior, monophonic wheezing that is louest over the central airway, normal Pa O2, an complete resolution of airflow obstruction with intubation. If upper airway obstruction is suspecte, the patient shoul be evaluate by using flow volume curves an laryngoscopy, either uring or after the ED visit, epening on the severity of the obstruction. ASSESSMENT OF LUNG FUNCTION In aults an most chilren oler than 5 years, serial measurement of lung function by using either FEV 1 or PEF performe at presentation an again 30 to 60 minutes after initial treatment is very useful in categorizing the severity of the exacerbation an inicating the nee for hospitalization. However, in patients experiencing a severe or life-threatening exacerbation with obvious airway compromise an cyanosis, these objective measurements are not recommene at the time of presentation because they provie little aitional information an can be very uncomfortable for the patient. In such cases the physical presentation shoul suffice for initial clinical assessment, an treatment shoul be initiate promptly. Thus 100% FEV 1 or PEF testing at triage is not a realistic or esirable goal. The optimal percentage of early spirometric testing (e.g.,. 80%) will epen on the frequency of very severe exacerbations in a given ED. For the patients who present in respiratory extremis, for whom initial FEV 1 or PEF assessment was not performe, it is important to note that they are likely to benefit from such testing later in the ED visit (e.g., after a few inhale short-acting b 2 -agonist treatments or before hospital amission). Assessment of lung function is more ifficult in chilren than in aults. No single assessment tool appears to be the best for etermining the severity of exacerbation in chilren (3 11), an in some chilren neither FEV 1 nor PEF results are obtainable uring an exacerbation. In one stuy only 65% of chilren age 5 to 18 years coul complete either of these measurements uring an exacerbation; among chilren younger than 5 years, these maneuvers were almost impossible (4). For this reason, pulse oximetry performe at the time of arrival to the ED an repeate 1 hour after initial treatment is recommene for assessment of lung function in infants an young chilren. After 1 hour, those chilren who continue to meet the criteria for a severe exacerbation have a greater than 86% chance of requiring hospitalization, those who meet the criteria for a moerate exacerbation have an 84% chance of requiring hospitalization, an those in whom the secon assessment inicates mil exacerbation have only an 18% chance of requiring hospitalization (7). In infants, assessment of lung function epens more on physical examination than on objective measurement. Use of accessory muscles, inspiratory an expiratory wheezing, paraoxical breathing, cyanosis, an a respiratory rate of greater than 60 breaths/minute all signal serious istress, as oes Sa O2 of less than 90%. Because infants are at greater risk of respiratory failure, a lack of response to short-acting b 2 -agonist therapy, as evience by either physical examination or objective measurements, inicates the nee for hospitalization (9). In infants it is particularly important to monitor Sa O2 by means of pulse oximetry because infants ventilation perfusion characteristics cause them to become hypoxemic more reaily than aults. Sa O2 shoul be normal for altitue, an a repeat Sa O2 of less than 92% on room air 1 hour after initial treatment is a reliable preictor of the nee for hospitalization (10, 12, 13). Use of oral corticosterois early in the episoe is essential but shoul not substitute for careful assessment by a physician. Most acute wheezing episoes result from viral infections an might be accompanie by fever; antibiotic treatment generally is not require. LABORATORY STUDIES Most patients with an asthma exacerbation o not require laboratory stuies. If orere, laboratory stuies must not result

3 Camargo, Jr., Rachelefsky, an Schatz: Managing Asthma Exacerbations in the ED 359 TABLE 2. CRITERIA FOR CATEGORIZING THE SEVERITY OF ASTHMA EXACERBATIONS (ORIGINALLY PUBLISHED AS FIGURE 5-3 IN THE EPR3 [1]) Mil Moerate Severe Subset: Respiratory Arrest Imminent Symptoms Breathlessness While walking While at rest (infant softer, shorter cry, ifficulty feeing) While at rest (infant stops feeing) Can lie own Prefers sitting Sits upright Talks in Sentences Phrases Wors Alertness May be agitate Usually agitate Usually agitate Drowsy or confuse Signs Respiratory rate Increase Increase Often. 30/minute Guie to rates of breathing in awake chilren: Age Normal rate, 2mo, 60/min 2 12 mo, 50/min 1 5 yr, 40/min 6 8 yr, 30/min Use of accessory muscles; suprasternal retractions Wheeze Usually not Commonly Usually Paraoxical thoracoabominal movement Moerate, often only en expiratory Lou; throughout exhalation Usually lou; throughout inhalation an exhalation Absence of wheeze Pulse/minute, Braycaria Guie to normal pulse rates in chilren: Age Normal rate 2 12 mo, 160/min 1 2 yr, 120/min 2 8 yr, 110/min Pulsus paraoxus Absent, 10 mm Hg May be present mm Hg Functional assessment PEF percent preicte or percent personal best Pa O2 (on air) an/or PCO 2 Sa O2 percent (on air) at sea level > 70 percent z percent or response lasts, 2 hours Normal (test not usually necessary) > 60 mm Hg (test not usually necessary) Often present. 25 mm Hg (ault), mm Hg (chil) Absence suggests respiratory muscle fatigue, 40 percent, 25 percent (Note: PEF testing may not be neee in very severe attacks), 60 mm Hg: possible cyanosis, 42 mm Hg (test not usually necessary), 42 mm Hg (test not usually necessary) > 42 mm Hg: possible respiratory failure. 95 percent (test not percent (test not, 90 percent usually necessary) usually necessary) Hypercapnia (hypoventilation) evelops more reaily in young chilren than in aults an aolescents. Definition of abbreviations: Pa O2 5 arterial oxygen pressure; PCO 2 5 partial pressure of carbon ioxie; PEF 5 peak expiratory flow; Sa O2 5 oxygen saturation. The presence of several parameters, but not necessarily all, inicates the general classification of the exacerbation. Many of these parameters have not been systematically stuie, especially as they correlate with each other. Thus, they serve only as general guies (Cham et al., 2002; Chey et al., 1999; Gorelick et al., 2004b; Karras et al., 2000; Kelly et al., 2002b an 2004; Keogh et al., 2001; McCarren et al., 2000; Rorigo an Rorigo 1998b; Rorigo et al., 2004; Smith et al., 2002). The emotional impact of asthma symptoms on the patient an family is variable but must be recognize an aresse an can affect approaches to treatment an follow up (Ritz et al., 2000; Strunk an Mrazek 1986; von Leupolt an Dahme 2005). in elay of treatment. Laboratory stuies are use to etect actual or impening respiratory failure, theophylline toxicity, or conitions that complicate asthma treatment, such as cariovascular isease, pneumonia, or iabetes. For example, arterial bloo gas measurements are helpful for evaluating Pa CO2 in patients with suspecte hypoventilation, those in severe istress, or those with FEV 1 or PEF results of 25% or less of preicte value after initial treatment. A complete bloo cell count is rarely neee, but might be appropriate in patients with fever or purulent sputum, but clinicians shoul bear in min that moest leukocytosis is common in patients with asthma. A chest raiograph is not recommene for routine assessment but shoul be obtaine for patients suspecte of having congestive heart failure, pneumothorax, pneumomeiastinum, pneumonia, or lobar atelectasis. A baseline electrocariogram an monitoring of cariac rhythm are appropriate in patients oler than 50 years an in those who have known coexistent heart isease or chronic obstructive pulmonary isease. TREATMENT OF ASTHMA EXACERBATIONS Prehospital Management The Expert Panel recommens that emergency meical services (EMS) proviers aminister supplemental oxygen an inhale short-acting bronchoilators to all patients who have signs or symptoms of an asthma exacerbation. EMS proviers shoul have a staning orer allowing them to provie albuterol to patients with an asthma exacerbation, which is consistent with

4 360 PROCEEDINGS OF THE AMERICAN THORACIC SOCIETY VOL Figure 1. Management of asthma exacerbations: EDan hospital-base care (originally publishe as Fig 5-6 in the EPR3 [1]). their legally authorize scope of practice an with local meical irectives. They shoul also have available a nebulizer, an inhaler plus a spacer/holing chamber, or both for b 2 -agonist aministration. If b 2 -agonist treatment is not possible, subcutaneous epinephrine or terbutaline can also be aministere for severe exacerbations (14, 15). When aministering bronchoilator treatment, EMS personnel shoul not elay patient transport to the hospital. Treatment can be repeate while transporting the patient to a maximum of three bronchoilator treatments uring the first hour an then one per hour thereafter. All EMS personnel shoul receive training in how to respon to the signs an symptoms of severe airway obstruction an impening respiratory failure (16). ED Management In the ED, the severity of the asthma exacerbation etermines the intensity of treatment an the frequency of patient monitoring. In general, primary treatment (i.e., aministration of oxygen, inhale b 2 -agonists, an systemic corticosterois) is the same for all asthma exacerbations, but the ose an frequency of aministration, along with the frequency of patient monitoring, iffer epening on the severity of the exacerbation (Figure 1 an Table 3). In aition to these three primary treatments, therapy with inhale ipratropium bromie or other agents might also be necessary in severe exacerbations. Oxygen. Aministration of oxygen through nasal cannulae or a mask is recommene to maintain Sa O2 at greater than 90% (. 95% in pregnant women an patients with concomitant heart isease). Oxygen saturation shoul be monitore until a clear response to bronchoilator therapy has occurre. Inhale short-acting b 2 -agonists. All patients shoul receive inhale b 2 -agonist treatment because repetitive or continuous aministration of these agents is the most effective means of reversing airflow obstruction (Table 3) (17 20). In the ED, three treatments aministere every 20 to 30 minutes is a safe strategy for initial therapy. Thereafter, frequency of treatment varies accoring to patient response (i.e., improvement in airflow obstruction an associate symptoms). About 60% to 70% of patients will respon sufficiently to the initial three oses to be ischarge, an most of these will emonstrate a significant response after the first ose (18, 21, 22). In patients with severe exacerbations (i.e.,, 40% of preicte value for either FEV 1 or PEF), continuous aministration of b 2 -agonists might be more effective than intermittent aministration (17). The uration of bronchoilation from shortacting b 2 -agonists is not precisely known, but might be significantly shorter than in patients with stable asthma. Because of

5 Camargo, Jr., Rachelefsky, an Schatz: Managing Asthma Exacerbations in the ED 361 TABLE 3. DOSAGES OF DRUGS FOR ASTHMA EXACERBATIONS (ORIGINALLY PUBLISHED AS FIGURE 5-5 IN THE EPR3 [1]) Dosages Meication Chil Dose* Ault Dose Comments Inhale short-acting beta 2 -agonists (SABA) Albuterol Nebulizer solution 0.15 mg/kg (minimum ose 2.5 mg) every (0.63 mg/3 ml, 20 min for 3 oses then mg/kg 1.25 mg/3 ml, up to 10 mg every 1 4 h as neee, or 2.5 mg/3 ml, 0.5 mg/kg/h by continuous 5.0 mg/ml) nebulization. MDI (90 mg/puff) 4 8 puffs every 20 min for 3 oses, then every 1 4 h inhalation maneuver as neee. Use VHC; a mask in chilren, 4 yr mg every 20 min for 3 oses, then mg every 1 4 h as neee, or mg/h continuously. 4 8 puffs every 20 min up to 4 h, then every 1 4 h as neee. Only selective beta 2 -agonists are recommene. For optimal elivery, ilute aerosols to minimum of 3 ml at gas flow of 6 8 L/min. Use large volume nebulizers for continuous aministration. May mix with ipratropium nebulizer solution. In mil-to-moerate exacerbations, MDI plus VHC is as effective as nebulize therapy with appropriate aministration technique an coaching by traine personnel. Bitolterol Nebulizer solution (2 mg/ml) See albuterol ose; thought to be half as potent as albuterol on mg basis. See albuterol ose. Has not been stuie in severe asthma exacerbations. Do not mix with other rugs. MDI (370 mg/puff) See albuterol MDI ose. See albuterol MDI ose. Has not been stuie in severe asthma exacerbations. Levalbuterol (R-albuterol) Nebulizer solution (0.63 mg/3 ml, 1.25 mg/0.5 ml 1.25 mg/3 ml) mg/kg (minimum ose 1.25 mg) every 20 min for 3 oses, then mg/kg up to 5 mg every 1 4 h as neee mg every 20 min for 3 oses, then mg every 1 4 h as neee. MDI (45 mg/puff) See albuterol MDI ose. See albuterol MDI ose. Pirbuterol MDI (200 mg/puff) See albuterol MDI ose; thought to be half as potent as albuterol on a mg basis. See albuterol MDI ose. Systemic (injecte) beta 2 -agonists Epinephrine 1:1, mg/kg up to mg every mg every 20 min for (1 mg/ml) 20 min for 3 oses sq. 3 oses sq. Terbutaline (1 mg/ml) Anticholinergics Ipratropium bromie Nebulizer solution (0.25 mg/ml) 0.01 mg/kg every 20 min for 3 oses then every 2 6 h as neee sq mg every 20 min for 3 oses, then as neee 0.25 mg every 20 min for 3 oses sq. 0.5 mg every 20 min for 3 oses then as neee MDI (18 mg/puff) 4 8 puffs every 20 min as neee up to 3 h 8 puffs every 20 min as neee up to 3 h Ipratropium with albuterol Nebulizer solution (each 3-ml vial contains 0.5 mg ipratropium bromie an 2.5 mg albuterol) MDI (each puff contains 18 mg ipratropium bromie an 90 mg of albuterol) Systemic corticosterois Prenisone Methylprenisolone Prenisolone 1.5 ml every 20 min for 3 oses, then as neee 3 ml every 20 min for 3 oses, then as neee 4 8 puffs every 20 min as neee up to 3 h 8 puffs every 20 min as neee up to 3 h (Applies to all three corticosterois) 1 2 mg/kg in 2 ivie oses (maximum 5 60 mg/) until PEF is 70% of preicte or personal best mg/ in 1 or 2 ivie oses until PEF reaches 70% of preicte or personal best Levalbuterol aministere in one-half the mg ose of albuterol provies comparable efficacy an safety. Has not been evaluate by continuous nebulization. Has not been stuie in severe asthma exacerbations. No proven avantage of systemic therapy over aerosol. No proven avantage of systemic therapy over aerosol. May mix in same nebulizer with albuterol. Shoul not be use as first-line therapy; shoul be ae to SABA therapy for severe exacerbations. The aition of ipratropium has not been shown to provie further benefit once the patient is hospitalize. Shoul use with VHC an face mask for chilren, 4 yr. Stuies have examine ipratropium bromie MDI for up to 3 h. May be use for up to 3 h in the initial management of severe exacerbations. The aition of ipratropium to albuterol has not been shown to provie further benefit once the patient is hospitalize. Shoul use with VHC an face mask for chilren, 4 years. For outpatient burst, use mg in single or 2 ivie oses for total of 5 10 ays in aults (chilren: 1 2 mg/kg/ maximum 60 mg/ for 3 10 ). Definition of abbreviations: ED 5 emergency epartment; MDI 5 metere-ose inhaler; PEF 5 peak expiratory flow; VHC 5 valve holing chamber. There is no known avantage for higher oses of corticosterois in severe asthma exacerbations, nor is there any avantage for intravenous aministration over oral therapy provie gastrointestinal transit time or absorption is not impaire. The total course of systemic corticosterois for an asthma exacerbation requiring an ED visit of hospitalization may last from 3 to 10 ays. For corticosteroi courses of less than 1 week, there is no nee to taper the ose. For slightly longer courses (e.g., up to 10 ), there probably is no nee to taper, especially if patients are concurrently taking ICSs. ICSs can be starte at any point in the treatment of an asthma exacerbation. * Chilren < 12 years of age.

6 362 PROCEEDINGS OF THE AMERICAN THORACIC SOCIETY VOL potential cariotoxicity, only selective short-acting b-agonists (albuterol, levalbuterol, an pirbuterol) shoul be aministere in high oses. In patients with miler exacerbations, treatment shoul consist of high oses (4 12 puffs) of a b 2 -agonist aministere by traine personnel through a metere-ose inhaler (MDI) with a valve holing chamber or by means of nebulizer therapy. Nebulizer therapy might be preferre for those patients who are unable to cooperate effectively in using an MDI because of their age, agitation, or more severe exacerbations. Systemic corticosterois. Systemic corticosterois are recommene for most patients (Table 3) because they spee the resolution of airflow obstruction an reuce the rate of post-ed relapse (23). In the ED, systemic corticosterois shoul be aministere to all patients with moerate-to-severe exacerbations an to those who o not respon to initial b 2 -agonist therapy. The Expert Panel recommens oral aministration of prenisone, which has been shown to have effects equivalent to those of intravenous methylprenisolone (24, 25) but is less invasive. Supplemental oses shoul be given to patients who regularly take corticosterois, even if the exacerbation is mil. In patients with moerate-to-severe exacerbations, early aministration of corticosteroi therapy might reuce the likelihoo of hospitalization (23). The Expert Panel agrees that current evience is insufficient to warrant recommening high-ose inhale corticosterois over oral corticosterois in the ED; more stuy is neee regaring the use of inhale corticosterois for acute treatment (26). Inhale ipratropium bromie. The Expert Panel recommens use of inhale ipratropium bromie for acute treatment in the ED. Multiple high oses (0.5 mg of nebulizer solution or 8 puffs by means of MDI in aults an mg of nebulizer solution or 4 8 puffs by means of MDI in chilren) shoul be ae to b 2 -agonist therapy to increase bronchoilation. The combination of a b 2 -agonist an inhale ipratropium bromie has been shown to reuce hospitalizations, particularly in patients with severe airflow obstruction (27, 28). Other treatments. Antibiotics are not generally recommene for the treatment of asthma exacerbations because viruses are a much more common cause of exacerbations than bacteria. Thus antibiotics shoul be reserve for relatively rare cases in which there is strong evience of a coexistent bacterial infection (e.g., pneumonia or sinusitis). Data on possible benefits of macrolie antibiotics are iscusse later in this issue, although their use is still not recommene in the absence of other clinical inications base on currently available ata. Aggressive hyration is not recommene for oler chilren an aults but might be appropriate for some infants an young chilren, who coul become ehyrate as a result of increase respiratory rate an ecrease oral intake. Flui status shoul be assesse before aministering hyration therapy. The Expert Panel oes not recommen the use of methylxanthines, chest physiotherapy, mucolytics, or seation. Repeat Assessment The Expert Panel recommens that patients with severe exacerbations unergo repeat assessment after the initial ose of inhale bronchoilator treatment an that all patients, regarless of exacerbation severity, are assesse after three oses of inhale bronchoilator treatment (i.e., min after initiation of therapy). Response to treatment in the ED is a better preictor of the nee for hospitalization than the severity of an exacerbation at the time of presentation (3, 5, 7, 9, 29 35). All repeat assessments shoul inclue the patient s subjective response to treatment, physical finings, an FEV 1 or PEF results (or arterial bloo gas measurements or pulse oximetry in patients with suspecte hypoventilation, those who are in severe istress, an those with FEV 1 or PEF results < 25% of preicte value; see earlier iscussion of laboratory stuies in INITIAL ASSESSMENT OF ASTHMA EXACERBATIONS IN THE ED). Impening Respiratory Failure Although most patients respon well to therapy, a small percentage will show signs of worsening ventilation. Because respiratory failure can progress rapily an is ifficult to reverse, early recognition an treatment are necessary. Signs of impening respiratory failure inclue an inability to speak, altere mental status, intercostal retraction (29), worsening fatigue, an a Pa CO2 of 42 mm Hg or greater. The Expert Panel recommens that intubation not be elaye once it is eeme necessary. Because intubation of a severely ill asthmatic patient is ifficult an can result in complications, other treatments, such as intravenous magnesium, heliox, an other treatments, are sometimes attempte. Intravenous magnesium sulfate has no apparent value in patients with exacerbations of lower severity, but it might be consiere (conitional recommenation) in those with life-threatening exacerbations an those whose exacerbations remain severe after 1 hour of intensive conventional treatment (36, 37). The selective use of intravenous magnesium sulfate alreay has been aopte by many acaemic EDs (38). The ose is 2 g over 20 minutes in aults an 25 to 75 mg/kg in chilren (up to a maximum of 2 g). Heliox-riven albuterol nebulization can also be consiere (conitional recommenation) in these patients (39, 40). Heliox also can be use to quickly ecrease the work of breathing. Unfortunately, the heliox literature is complicate by the small number of subjects in most trials an by important methoological ifferences between trials. For example, some stuies have neglecte to account for the ifferent effect of heliox versus oxygen on respirable mass (41). A large multicenter stuy is neee to resolve lingering questions about this promising therapy. Intravenous aministration of b 2 -agonists is a largely unprove treatment (20), an the Expert Panel oes not recommen use of intravenous isoproterenol in the treatment of asthma because of the anger of myocarial toxicity. Similarly, there is insufficient evience to ate to recommen the use of leukotriene moifiers (42) or noninvasive ventilation (43) in the treatment of acute asthma. Intubation The Expert Panel makes the following recommenations with regar to intubation: Patients presenting with apnea or coma shoul be intubate immeiately. Persistent or increasing hypercapnia, exhaustion, an epresse mental status strongly suggest the nee for ventilatory support. Consultation with or comanagement by a physician expert in ventilator management is essential because ventilation of patients with severe asthma is complicate an risky. Because intubation is ifficult in asthmatic patients, it shoul be one semielectively an before respiratory

7 Camargo, Jr., Rachelefsky, an Schatz: Managing Asthma Exacerbations in the ED 363 Figure 2. ED asthma ischarge plan (originally publishe as Fig 5-7 in the EPR3 [1]). arrest occurs. Once intubation is eeme necessary, it shoul not be elaye an therefore shoul be performe in the ED, with the patient transferre to an intensive care unit appropriate to the patient s age. Two issues must be consiere at the time of intubation. First, intravascular volume shoul be maintaine or replace because hypotension commonly accompanies the initiation of positive pressure ventilation. In aition, high ventilator pressures, with their associate risks of barotrauma, shoul be avoie. Permissive hypercapnia or controlle hypoventilation is the recommene ventilator strategy because it provies aequate oxygenation while minimizing airway pressures an the possibility of barotrauma (44 46). However, this strategy is not uniformly successful in critically ill asthmatic patients, an aitional therapies are uner evaluation. EDUCATION OF THE ASTHMATIC PATIENT IN THE ED The Expert Panel acknowleges that more research is neee in this area but, base on currently available information, avises offering a focuse patient-eucation intervention to iniviuals who present to the ED with an asthma exacerbation. The general points of focus for this intervention are general asthma eucation, review of inhaler technique, a simple written asthma ischarge plan, an referral for follow-up. To help patients recognize an respon to symptoms of asthma, the provier shoul prepare a simple asthma ischarge plan for asthma symptoms an explain it an be sure to inclue aily treatment plans, as well as plans for how to manage an exacerbation (Figure 2). Because many patients o not use an inhaler correctly, it is important to review inhaler technique with the patient an correct technique errors (Figure 3). Also, refer the patient for a follow-up asthma care appointment with a primary care physician or an asthma specialist within 1 week

8 364 PROCEEDINGS OF THE AMERICAN THORACIC SOCIETY VOL Figure 3. ED asthma ischarge eucation: how to use your MDI (originally publishe as Fig 5-7b in the EPR3 [1]). an encourage the patient s participation in a more formal asthma eucation program. PATIENT DISCHARGE The Expert Panel recommens that patients who emonstrate a rapi response to treatment be observe for 30 to 60 minutes after the most recent ose of bronchoilator therapy to ensure stability of response before ischarge to home. In general, patients can be ischarge if FEV 1 or PEF results are 70% or more of preicte value or personal best an symptoms are minimal or absent. Patients with an incomplete response to therapy (i.e., FEV 1 or PEF results of 50% to 69% of preicte value or personal best) an with mil symptoms shoul be assesse on an iniviual basis, taking into account any risk factors for asthma-relate eath. Extene treatment or observation in a holing or overnight unit might be appropriate for some patients. Patients given systemic corticosterois shoul be prescribe sufficient meication to continue therapy for 3 to 10 ays after ischarge. For those patients consiere at high risk of nonaherence, intramuscular epot injections might be as effective as oral corticosterois in preventing relapse (47 49). The nee for aitional corticosteroi treatment shoul be assesse at a follow-up visit. Patients who are currently receiving inhale corticosteroi therapy shoul continue this treatment while taking systemic corticosterois. The Expert Panel recommens that clinicians consier (conitional recommenation) initiating inhale corticosterois at ischarge in patients not alreay receiving them. Because an ED visit is often the result of inaequate longterm management of asthma, clinicians shoul stress the nee for regular care in an outpatient setting an ensure that all patients are referre for a follow-up meical appointment. When possible, the ED shoul scheule such an appointment before ischarge to increase the likelihoo that the patient will keep the appointment. A ischarge plan is useful to ensure that patients are provie with the necessary meications an taught how to use them, instructe in how to monitor symptoms, given a follow-up appointment, an instructe in a written plan for managing recurrence of airflow obstruction (Figures 2 an 3). SUMMARY Most asthma exacerbations require immeiate care, close observation for eterioration, frequent treatment, an repeate measurement of lung function. The NAEPP Expert Panel recommens that all clinicians treating asthmatic patients shoul be prepare to treat an asthma exacerbation, recognize the signs an symptoms of severe an life-threatening exacerbations, an be familiar with the risk factors for asthma-relate eath. Because infants are at greater risk for respiratory failure, clinicians shoul also be familiar with special consierations in the assessment an treatment of infants experiencing asthma exacerbations.

9 Camargo, Jr., Rachelefsky, an Schatz: Managing Asthma Exacerbations in the ED 365 All patients presenting with an asthma exacerbation shoul be evaluate an triage immeiately, with treatment institute promptly on etermination of a moerate, severe, or lifethreatening exacerbation. Primary treatment consists of aministration of oxygen, inhale b 2 -agonists, an systemic corticosterois, with the ose an frequency of aministration, along with the frequency of patient monitoring, epenent on the severity of the exacerbation. After treatment an repeat assessment, patients can generally be ischarge if FEV 1 or PEF results are 70% or more of preicte value or personal best an symptoms are minimal or absent. Before ischarge, patients shoul be prescribe 3 to 10 ays of corticosteroi therapy to reuce the risk of recurrence an provie with a follow-up appointment to evaluate the nee for aitional corticosteroi treatment. Clinicians shoul consier (conitional recommenation) initiating inhale corticosterois. Patients shoul also be eucate on correct use of the inhaler an shoul be given a written ischarge plan for increasing meications or seeking care in the event of worsening asthma. Author isclosures were obtaine by the Journal of Allergy an Clinical Immunology (JACI) using questions etermine by the American Acaemy of Allergy, Asthma an Immunology (AAAAI) an JACI. Questions pertaine to: employment; financial interests between the author or members of the author s immeiate family or househol with organizations an commercial interests; research support uring the past calenar year; an legal consultation services/expert witness testimony uring the past calenar year. Authors were aske to state ollar amounts in ranges of either, $10,000 or > $10,000. Authors were not require to isclose other facts that are now requeste by PATS in conformance with American Thoracic Society policy, incluing knowlege of any significant financial relationship between the author s institution or employer an relevant commercial interests, an all relationships with tobacco entities. Disclosure of potential conflict of interest: C.A.C., Jr. has been a consultant, speaker, or avisory boar member for AstraZeneca, Critical Therapeutics, Dey, Genentech, GlaxoSmithKline, Merck, Novartis, an Schering-Plough an has receive research support from the National Institutes of Health, AstraZeneca, Critical Therapeutics, GlaxoSmithKline, Merck, Novartis, an Respironics. G.R. has been a speaker or avisory boar member for AstraZeneca, Schering-Plough, CSL Behring, Merck, an Sanofi Aventis an has provie legal consultation or expert witness testimony on the topic of environmental injuries, mostly molrelate. 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