Update on Acute Asthma Carlos Camargo, MD, DrPH Emergency Medicine, MGH Channing Laboratory, BWH Harvard Medical School

Outline of Presentation Background NAEPP guidelines Novel therapies Preventive interventions Summary

Definition of Asthma Chronic lung disease characterized by: –Airway narrowing that is reversible (± completely) either spontaneously or with treatment –Airway inflammation –Airway hyper-responsiveness to a variety of stimuli. Episodic dyspnea with associated wheezing Heterogeneous group with: –Shortness of breath –Wheezing –Cough ATS. ARRD 1987

NAEPP Guidelines, 1997 National Asthma Education and Prevention Program (NAEPP) Classification of chronic asthma: –Mild intermittent asthma –Mild persistent asthma (>2 days/wk, >2 nights/mo) –Moderate persistent asthma –Severe persistent asthma Inhaled corticosteroids (ICS) are “preferred treatment” for all patients with persistent asthma

Epidemiology million Americans (6-10% prevalence) 10 million office visits + 2 million ED visits + 500,000 hospitalizations + 5,000 deaths Major cause of school and work absences At least $12 billion per year Increasing burden for years... but now flat (or  )

Asthma Prevalence, * 11.3 * 4.3 * 7.3 NHIS 2001

Asthma Prevalence, * 11.3 * 4.3 * 7.3 NHIS 2001

Asthma Mortality,

ED Visits for Asthma, Visits in thousands NHAMCS Database

MARC –Founded 1996 –Goal: To improve care of acute asthma & other airway disorders –Funded by NIH, industry, foundations –Emergency Medicine Network –

EMNet Sites (137 US sites) 9/22/04

Potential for Improving Asthma ED is often used for asthma care –2 million ED visits per year –Most asthma hospitalizations begin in the ED Among ED patients (MARC data): –74% adults (63% children) use ED for all “problem” asthma care –45% adults (31% children) receive all asthma Rx from ED –With PCP: % for problem care; % for all Rx High-risk population

ED Patients with Acute Asthma

ED and Hospital Management: Goals 1.Correct significant hypoxemia 2.Rapidly reverse airflow obstruction 3.Decrease likelihood of recurrence NAEPP, 1997

ED and Hospital Management: Initial Treatment Mild-to-Moderate Exacerbation (PEF > 50%) Oxygen to achieve O 2 sat > 90% Inhaled  2 -agonist by MDI or neb, up to 3 in 1 st hr Oral corticosteroid if no immediate response or if patient recently took oral corticosteroid NAEPP, 1997

ED Treatment, % 10% 20% 30% 40% 50% 60% 70% 80% 90% Antiasthmatic Corticosteroid Antimicrobial % Usage National Center for Health Statistics, CDC ED Treatment,

Systemic Steroids at Discharge P for trend <0.001

ED and Hospital Management: Initial Treatment (continued) Severe Exacerbation (PEF < 50%) Oxygen to achieve O 2 sat > 90% Inhaled high-dose  2 -agonist and anticholinergic by neb q 20 minutes or continuously for 1 hour Oral corticosteroid NAEPP, 1997

ED and Hospital Management: Initial Treatment (continued) Impending or Actual Respiratory Arrest Intubation and mech ventilation with 100% O 2Intubation and mech ventilation with 100% O 2 Nebulized -agonist and anticholinergicNebulized  2 -agonist and anticholinergic IV corticosteroidIV corticosteroid Admit to hospital intensive careAdmit to hospital intensive care NAEPP, 1997

2002 Update on Selected Topics Antibiotics not recommended for acute asthma ICS are preferred treatment for children of all ages with persistent asthma ICS + long-acting  -agonist is the preferred treatment for moderate or severe persistent asthma in individuals age 6 and older NAEPP, 2002

Dual Therapy with ICS + LABA (weeks)

Dual Therapy with ICS + LABA (days)

Novel Therapies in the ED IV magnesium Heliox IV leukotriene modifiers

IV Mg for Acute Asthma – Admit Rate

Heliox for Severe Acute Asthma – PEF

IV Montelukast for Acute Asthma – FEV 1

ED-Initiated Preventive Interventions High-risk population Use of ED for “problem asthma” care + asthma Rx What interventions are feasible in the ED setting? Examples from MARC: 1.ICS initiation at discharge from ED 2.Asthma education programs 3.Bridging the gap between ED & primary asthma care

Initiation of ICS at Discharge *

ICS after the ED -- Relapse at Days

Prevention of Repeat ED Visits

Prevention of Fatal Asthma MDIs of Inhaled Corticosteroids per Year Rate Ratio of Asthma Death 1 Suissa & Ernst, JACI 2001.

Mission Statement To promote optimal asthma management and quality of life among individuals with asthma, their families and communities, by advancing excellence in asthma education through the Certified Asthma Educator process. National Asthma Educator Certification Board

Follow-up with PCP Philadelphia study –randomized trial, 1 center, n=178 –$25 intervention (free meds, taxi vouchers, 48-hr call) –f/u with PCP: usual care (29%) vs. intervention (46%), p=0.02 RR=1.6 (95%CI, ) EMF Center of Excellence Award –Recently completed RCT at 9 EMNet sites –1 month: 50% increase in PCP follow-up (ACEP 2001) Baren et al, Ann Emerg Med 2001

Follow-up with PCP Philadelphia study –randomized trial, 1 center, n=178 –$25 intervention (free meds, taxi vouchers, 48-hr call) –f/u with PCP: usual care (29%) vs. intervention (46%), p=0.02 RR=1.6 (95%CI, ) EMF Center of Excellence Award –Recently completed RCT at 9 EMNet sites –1 month: 50% increase in PCP follow-up (ACEP 2001) –6 and 12 months: no diff in clinical outcomes … (ACEP 2002) –Next steps … facilitated referral to specialists?

Summary Asthma epidemiology NAEPP guidelines –1997: O2 prn, inhaled ß-agonist + antichol, systemic steroids –2002: ICS for children of all ages with persistent asthma ICS + LABA for age 6+ with moderate-severe persistent Novel treatments – severe exacerbations only Prevention at all clinical encounters! –Start ICS at ED discharge … consider ICS + LABA –Asthma education (brief) … consider outpatient session –Arrange continuing care … consider referral to specialist