Variations and Gaps in Management of Acute Asthma in Ontario Emergency Departments

Original Research ASTHMA

Variations and Gaps in Management of Acute Asthma in Ontario Emergency Departments· M. Diane UJugfIeed, MD, MSc; Nancy Garm.!, RRTf; Kenneth R. Chapman, MD, FCCP; Usa Cicutto, PhD; Robert Dales, MD; Andrew G. Day, MSc; Wilma M. Hopman, MA; Miu Inn, PhD; Malrolm R Sears, MD; Kim Szpiro, MSc; Teresa To, PhD; and Nigel A M. Paterson, MD, FCCPt Background: Variation in hospitalization rates for acute asthma in Ontario may retlect gaps between evidence and current emergency department (ED) management. We investigated ED management of asthma and differences in practice patterns for pediatric « 20 yean old) and adult (ii!: 20 yean old) patients in Ontario EDs. Method: Patient characteristics and ED management during a I-year period were assessed by questionnaire and chart abstractions in a stratified sample of 16 Ontario hospitals. Variation between sites was assessed by one-way analysis of variance, Kruskal-Wallis test, or X" test. Be'fllt,: Reported results are based on the first of 2,671 pediatric (42.0% female) and 2,078 adult (66.7% female) visits with a corresponding questionnaire. Asthma severity, comorbidities, access to care, and prehospital management varied Significantly among sites (all p < 0.001). Documentation of peak expiratory flow (27.2% of pediatric [age ii!: 7] and 44.3% of adult charts), use of systemic steroids in ED (35.2% pediatric and 33.0% adult charts) and on discharge (31.7% pediatric and 33.2% adult charts), and referrals to asthma services (2.8% pediatric and 2.7% adult charts) varied among sites (all p < 0.001). Admission (%) was directly related to time to receive systemic steroids in ED in adults (r = 0.76; P = 0.004). Repeat ED visits (%) were inversely related to new inhaled steroid prescription on discharge in adults (r -0.64; p 0.02). Conclfl,io,..: Knowledge translation initiatives are warranted to increase adherence with best practices in emergency management of asthma (such as objective assessment of airflow rates, use of systemic steroids, and referrals) in order to reduce variations in care and improve outcomes of severe acute asthma. (CHEST 2009; 135:124-136)

=

=

Key words: adults: asthma: emergency department management: epidemiology hospitalization rates; pediatric: regional variation

Abbreviations: CAEP

= Canadian Association of Emergency Physicians: CTS = Canadian Thoracic Society: CXR = chest radiograph: df = degrees of freedom: ED = emergency department: FDR = false discovery rate; ICS = inhaled corticosteroid; PEFR = peak expiratory flow rate

Asuboptimal sthma remains a global health concern due to control and resultant morbidity and

mortality.l-' Despite the development of national and international guidelines for the diagnosis and management of asthma,~10 considemble under-treatment of chronic asthma persists. 1l- 14 Guidelines committees are increasinglyrecognizingthe need to focus efforts on knowledge translation and implementation strategies, which address the most prevalent and important care gaps across various pmctice settings. 724

Gaps between evidence-based emergency asthma management guidelines~lO and practice were documented in Canada'! prior to the development and implementation of the Canadian Association of Emergency Physicians (CAEP)/Canadian Thoracic Society (CI'S) emergency department (ED) asthma guidelines," In particular, objective measures of airflow rates were used infrequently, bronchodilator dosing was suboptimal, and systemic corticosteroidswere routinely prescribed on discharge by fewer than 25% of physiOriginal Research

clans. Canadian ED asthma guidelines have not been updated since 1995, and published data on current practice patterns are limited predominantly to single and/or academic center studies. Reports of suboptimal compliance with guidelines in academic centers and North American EDs with asthma protocols 15,16 are concerning and may even underestimate the prevalence, magnitude, and variations in gaps between evidence and current practice for the management of acute asthma in many Canadian EDs not involved in asthma research, particularlycenters without asthma pathwaysP Recently, significant regional variations in hospitalization rates for pediatric and adult asthma in

Ontario were documented, largely attributable to factors other than ED visit rates, such as variation in patient characteristics and/or ED management.!" The primary objective of the current analysis was to examine site-specific differences in ED practice patterns and consistency with guidelines. Secondary objectives were to characterize individuals who attend Ontario EDs for urgent asthma care, and examine the relationship between site-specific adherence with guidelines, site characteristics, and admission and relapse rates,

"From the Queen's University (Drs. Lougheed and Lam). Kingston, ON. Canada: Clinical Research Centre (Dr. Lougheed, Mr. Day. Ms. Hopman, and Ms. Szpiro).Kingston Generaf'Hospital. Kingston, ON. Canada; William Osler Health Centre (Ms. Gatvey), Brampton, ON, Canada; University of Toronto (Drs. Chapman and Cicutto), Toronto, ON, Canada; University of Ottawa (Dr. Dales), Ottawa, ON, Canada: McMaster University (Dr. Sears), Hamilton, ON, Canada: Child Health Evaluative Sciences (Dr. To). The Hospital for Sick Children, Toronto, ON. Canada; and University of Western Ontario (Dr. Paterson). Londoo, ON. Canada. fCurrently at the Ontario Ministry of Health and Long-Term Care, Toronto, ON. Canada. [For the Ontario Respiratory Outcomes Research Network. This study was funded by the Canadian Institutes of Health Research (CIHR). the Ontario Thoracic Society.and unrestricted grants from Altana, AstraZeneca, and Boehringer Ingelheim. Dr. Lougheed has received grants in the last 3 years from the Ontario Ministry of Health and Long-Term Care. Ontario Lung Association. AllerGEN NCE. Topigen Pharmaceuticals. and Ception Therapeutics; and honoraria from GlaxoSmithKlineInc. Epidemiology Advisory Board. Dr. Garvey is currently the Program Coordinator for Ontario Ministry of Health and LongTerm Care's Asthma Plan of Action (effective August 2004. after completion of the study) and refers to the study in presentations related to the Ontario Emergency Department Asthma Care Project. Dr. Chapman has served on the advisory boards or consulted with Astra Zeneca, Boehringer-Ingelheim. GlaxoSmithKline, Novartis, Nycomed,Pfizer, Roclie,ScheringPlough,Talecris and ZLB Behrig; has undertaken research sponsored or funded in whole or in part by AstraZeneca, Boehririger-Ingelheim, GlaxoSmithKline. Merck Frosst. Novartis, Nycomed, Parangenix, Roche. and ZLB Bebrig, and has participated in continuing medical education programs or presentations sponsored by AstraZeneca, Boehrfuger-Ingelheim. GlaxoSmithKline, Merck Frosst, Novartis, Nycomed, Pfizer, and Talecris, He holds an endowed chair at the University Health Network in Toronto-the CIHR-GSK Chair in Respiratory Health Care Delivery. Dr. Cicutto has received grants from the Ontario Ministry of Health and Long-Term Care, Ontario Lung Association, and consultant fees from Astra Zeneca and GlaxoSmithKline Inc. Dr. Sears provides consulting services and receives speaker fees from AstraZeneca, GlaxoSmithKline, Merck Frosst Canada. and Nycorned (Altana). He has had research funding in the last 3 years from Merck Frosst Canada. Dr. Dales. Mr. Day, Ms. Hopman, Dr. Lam. Ms. Szpiro, and Drs. To and Paterson have no conflicts of interest to disclose regarding the subject matter of this article. Manuscript received February 27. 2008: revision accepted September 24. 2008. Reproductionof thisarticleis prohibited withoutwritten permission from the AmericanCollegeof Chest Physicians (VI'Io\oW.cliestjournal. orgtmisclreprints.shtml). Correspondence to: M. Diane Lougheed, MD, MSc, Division of

An observational study was conducted in a stratified sample of 16 Ontario hospitals that admit either children, adults. or both. Details of the sampling method and a complete list of participating sites were reported previously. IS ED visits for acute asthma in children « 20 years of age) and adults (:2= 20 years of age) between March 1. 2001 and February 28,2002 were identified by trained research assistants at each site. as previously described. IS Eligible patients. parents. or guardians were contacted and invited to provide informed consent and participate in the study. The Queen's University Health Sciences and Affiliated Teaching Hospital Research Ethics Board and the ethics committees of all participating hospitals approved the study.

Respirology, Departmentof Medicine, Queen's University, Kingston, ON, Canada K7L 3N6;e-mail: [email protected] DOl: IO.13781chest.08-0371 www.chestjoumal.org

.

MATERIALS AND METHODS

Data Collection Questionnaire: A validated questionnaire.w modified to an interviewer-administered format and to allow parents/guardians to answer on behalf of pediatric patients. was used to collect information on socio-demographics. asthma history and control. access to care, and usual ambulatory care. including medications and self-management practices. The inter-rater reliability of the modified questionnaire was 88.0% for a pediatric participant (n = 15 interviewers) and 87.0% for an adult participant (n = 15 interviewers). comparable to the published test-retest reliability of the original questionnaire (88.0%). Medical Record Abstraction: Date of presentation. age. sex, six-digit postal code. discharge diagnosis, and disposition were collected for all identified visits. For participants. additional data abstracted included time of presentation, time seen by healthcare providers. presenting symptoms. physical examination. investigations, medications administered in the ED. patient education in the ED, discharge prescriptions, and follow-up instructions. The intra- and inter-rater reliability of data abstraction by trained research associates were 96.7% (n = 13 raters abstracted the same chart twice) and 97.6% (n = 52: 13 raters abstracted four charts each), respectively. Statistical Analysis Repeat visits by an individual were collected, but only the first visit with a questionnaire completed was included in this analysis. Demographics,disposition, and dischargediagnoses of participating visits were compared to nonparticipatingvisits: amongparticipating visits, included visits (first participating visit with a corresponding questionnaire) were compared to excluded visits (repeat visits or visitswithout a correspondingquestionnaire). Agewascompared by the t test and the distributions of gender, admission status. and discharge diagnoses were compared by the test.

,c

CHEST 1135/31 MARCH, 2009

72&

For the included sample, patient characteristics and ED practice patterns were described overall and compared among sites. Categorical variables were reported as overall percentages and the range of site-specific percentages. Site heterogeneity was tested by the X2 test. Continuous variables are presented as overall means or medians and ranges of these site-specific measures. Site heterogeneity was tested by the one-way analysis of variance for age and the Kruskal-Wallis test for all other continuous variables. In addition, key categorical variables were graphed by site as proportions with exact binomial 95% confideuce intervals, while key continuous variables were displayed as box plots. In graphs, site results were sorted in ascending order of the mean values of each variable; as such, sites are not in the same order on each graph. The analysis was repeated in the subgroup of patients with ages of 5 to 39 years to assess the impact of diagnostic misclassification, due to bronchiolitis in younger children or COPD in adults over 39 years old. Correlation between site-level hospital admission rates, 28-day ED relapse rates, and site-level averages of selected guideline adherence variables were estimated by Pearson correlation coefficient. These site-level variahles were then compared between urban and rural sites and between academic and community sites by the independent t test. The reported site level statistics, including the Pearson correlation coefficients and the t tests, were weighted so that each site's contribution to the statistics was proportional to the number of visits included from each site. This weighting by size increased the statistical efficiency, but retained the overall degrees of freedom (elf) so that each site counted as a single observation. The entire analysis was also repeated using all available data, including repeat visits. Children « 20 years old) and adults (~ 20 years old) were analyzed separately. All analyses were performed using statistical software (SAS, version 9.1; SAS Institute; Cary, NC). The reported p-values were not adjusted for multiplicity of comparisons, but the type I error rate was assessed by the false discovery rate (FDR) approach of Benjamini and Hochberg.211

RESULTS

One site was excluded due to incomplete data capture leaving a total sample of 15 sites (13 for each age group). Identification of index visits in children (n = 2,671) and adults (n = 2,078) is illustrated in Figure 1, The pediatric sites each contributed between 47 and 434 patients to the analysis while the adult sites each contributed between 40 and 391 patients. There were small but statisticallysignificant differences between participants and nonparticipants in age and sex in adults, and percentage of admissions, and discharge diagnoses in both age groups (Table 1). Among adults, nonparticipants were younger than participants (39.1 ± 16.2 vs 41.4 ± 16.0 years, respectively; t = 4.9; df = 4,760; P < 0.(01) and were less commonly female (57.5% vs 66.0%, respectively; x. 2 = 35.7; df = 1; P < 0.001). In both children and adults, nonparticipants were less commonly admitted than participants (children, 8.9% vs 12.8%, respectively; x.2 = 21,0; and adults, 5.1% vs 8,5%, respectively; x.2 = 21,6; both df = 1 and p < 0,001). 726

[ PcdialricVi.ilSExcludedn48

[

[

Total ED visits captured ] n-10.766

Pediatric ViSitS] n=5618

Nonparticipating Visits n~2283

rL

Participating Visits n=3335(59%) Mean(range) # visits: 1.3 (1-12)

Repeat Visits 11"'582

1-d [

FirstVisitswithout a Conesponcling Questionnaire n42

-+__---11

11-_ _

J

Missing A8. n=42

1

I

~ ~

Participating Visits (First Visitswith a Corresponding Questinnnaire) ...2671

1

Adult Visits n=4762

I r Nonparticipating Visits I n n-2336 Participating Visits n~242b (51%) Meanlrange)# visits: 1.2(1-23)

Fint valts ] n~2753

Adult VisilS Excluded- ] n=256

k-f

Flrsl ViSiIS] \

Repeat

Visits n-322 '----_ _oJ

n~2104

r--

FirstVisits without a Corresponding Questionnaire lF26

Participating Visits (First ViailS witha Corresponding Questionnaire) .-2078

FIGURE 1. Identification of first ED visit per pediatric and adult patient with a matching questionnaire for the index visit. *Exeluded visits; pediatric (n = 33 visits [18 participants] from adult site; n = 55 visits [2 participants] from excluded site); adults (n = 256 visits [25 participants] from excluded site). Nonparticipating visits include patients unable to be contacted by telephone and patients who did not consent to participate.

Asthma History and Management Preceding the ED Visit Questionnaire data are presented in Table 2. Significantvariations between sites in demographics, asthma severity based on the classification system outlined by the Global Initiative for Asthma," comorbidities, access to care, health-care utilization, and management prior to the index ED visit are evident for both age groups. Most pediatric and adult participants reported having doctor-diagnosed asthma, with overall rates of 75,9% (range, 65.8 to 87.2%; l 2 = 50; df = 12) and 83.9% (71.3 to 93,6%; x. = 65; df = 12; P < 0.001), respectively. The duration of diagnosed asthma varied Significantly among sites within both age groups with overall median durations of 3 years (range, 2 to 5 years; x.2 = 65; df = 12; P < 0.0001) and 14 years (11 to 20 years; l = 31; df = 12; P = 0.0023), respectively.

Asthma Exacerbations Characteristics and ED Management Chart abstraction data are presented in Table 3 and Figures 2-6. There were significant variations between sites for both age groups in administrative OriginalResearch

Table l-Characteriatic. of Participant. and Nonparticipants* Children

Adults

Participating Visits Characteristics Age. yr Female gender Admitted to hospital Hospital discharge diagnosis Missing Asthma COPD/Asthma HAD Suspected cases of asthma

Participating Visits

Nonparticipating Visits (n = 2,283)

I Excluded]

(n = 664)

Included I (n = 2,671)

Nonparticipating Visits (n = 2.336)

6.9 ::!: 0.6 39,0 8.9§

6.5::!: 0.3 38.9 13.4

6.8::!: 0.3 42.0 12.7

39.1 ::!: 16.2§ 57.5§ 5.1§

0.4 70.3 0.1 26.3 3.0

0.2 70.6 0.3 25.2 3.8

0.2

1.4

§

66.8

0.1 27.6 5.4

§

I

Excluded* (n = 348)

40.9::!: 15.2 61.8 12.6

0.6

75.7

77.9

2.4 19.1 1.4

0.9

19.:3

1.4

Included = 2,(78)

(n

41.5::!:16.1

66.7 7.811 0.1

7.3.5 1.1

21.5

3."

*Values are given as the mean ::!: SD or %. RAD = reactive airway disease. t A total of .582 repeat visits plus 82 first visits without a corresponding questionnaire. *A total of 322 repeat visits plus 26 first visits without a corresponding questionnaire. §p < 0.001 compared to participating visits (excluded and included). lip = 0.004 compared to participating visits excluded.

outcomes such as length of stay (Fig 2), presenting symptoms and triggers, severity of the exacerbation (based on the CAEP/CTS classification"), investigations including documentation of peak expiratory flow rate (PEFR) [Fig 3], and management in ED and on discharge, particularly in the use of systemic steroids (Figs 4, 5) and referrals to specialized asthma services (Fig 6). Three sites re-abstracted a random sample of charts in which salbutamol was not administered in the ED, In all instances, the documentation of the disposition diagnosis of asthma was verified. Reasons for not administering salbutamol included: prescription given, inhaler teaching provided, alternative bronchodilator administered, multiple doses of salbutamol taken before attending the ED, patient declined treatment, contraindication (side effects).

Subanalyses of Children (5 to 19 years old) and Adults (20 to 39 years old) Analyses of first visits with corresponding questionnaires in children 5 to 19 years of age (n = 1,348; 11.0 ± 4.4 years) and in adults 20 to 39 years of age (n = 1,117; 29.3 ± 5.8 years) revealed significant site heterogeneity similarto the overallresults. In addition, most of the reported valueswere similar (within 5%) in the overall groups compared to the respective age category subgroups. Variables which were appreciably different betweenthe overall pediatric and adult data sets and the age restricted subgroups are outlined below, In children 5 to 19 years old, the prevalences of comorbidities were as follows: bronchiolitis, 13.7% (site range, 0.0 to 45.0%; X2 = 61; df = 12; P < 0.001 for site heterogeneity); and positive allergy skin test result, 38.4% (range, 8.5 to 51.8; www.chestjoumai.org

x2 =

64; df = 12; P < 0.001). In the adults 20 to 39 years old, the reported prevalence of COPD was 10.5% (range, 0.0 to 29.0%; X2 = 58; df = 12; P < 0.0001). The prevalences of current smoking in children 5 to 19 years old and adults 20 to 39 years old were 7.3% (range, 1.2 to 12.5%; X2 = 18; df = 12; P = 0.112) and 34.6% (range, 12.5 to 53.1%; X2 = 35; df = 12; P = 0.0005), respectively. Chest radiographs (CXRs) were performed in children 5 to 19 years old and adults 20 to 39 years old at 26.0% of visits (range, 9.5 to 37.6% of visits; X2 = 49; df = 12; P < 0.0001) and 31.5% of visits (range, 13.0 to 50.0% of visits; X2 = 33; df = 12; P = 0.001), respectively.

Associations Between Site-Level Adherence With Guidelines and Outcomes For both age groups, hospital admissions were higher in community than in academic hospitals and systemic steroid use in the ED and after discharge were more common in urban than rural sites (Table 4). Sites that more often added oral steroids at discharge were more likely to have used systemic steroids in the ED (adult sites: r = 0.69, P = 0.009; pediatric sites: r = 0.78, P = 0.002) and were more likely to have documented PEFR (r = 0.64, P = 0.019; adult sites only). Correlations between site-level ED and discharge management and admission percentage and repeat ED visit rates are presented in Table 5. DISCUSSION

This multicenter study of Ontarians who sought ED care for an asthma exacerbation and their subCHEST/135/ 3/ MARCH, 2009

7~

Table 2--Althma Hiatory and Management Preceding the ED Vilit (Queationnaire Data)* Pediatric Participants Variables Sociodemographic variables Age, yr Female gender Household income] < $25,000 $25,000-$50,000 < $50,000 Education level High school graduate Asthma severity (GINA) Mild Moderate Severe Comorbid conditions COPD Bronchiolitis Allergy skin test positive Current smoker Exposures in home Furry or feathered pets Second-hand smoke Access to care See doctor for asthma Type of doctor: specialist Dmgplan Health-care utilization ED visit ever ED visit in previous 12 mo Hospitalizations in previous 12 mo Seen an asthma Specialist ever Asthma education program ever Management prior to ED SABA ICS LABA ICS + LABA LTRA Systemic steroids Home peak flow monitoring Action plan (verbal or written) Written action plan

I

No. t Overall Site Range

2,671 2,671 1,945

'It Statistic i

6.8§ 42.0

4.4-10.4 35.7-54.7

35.2 41.2

23.5

9.0--36.0 24.8-61.5 7.7--58.3

84.4

5.2-92.3

52.8 24.6 22.6

34.0-86.8 7.5-35.0 5.7-46.8

2,559 2,665 2,665

18.6 24.6 3.7

1.4-42.2 6.5-37.7 0.4-6.8

109

2,664 2,666

49.0 25.5

2,667

86.9

2,647 2,671

Adult Participants p Value

"

No.t Overall Site Range X2 Statistic]

13 21 160

< 0.0001 2,078 0.0549 2,078 < 0.0001 1,603

414

< 0.0001 2,067 < 0.0001 2,078

163

41.5§ 66.7

34.8-45.0 60.4-78.7

34.0 37.1 28.9

16.9-45.0 12.9-72.3 2.1--58.1

78.2

66.0--97.9

32.6

34.4

33.0

16.2-72.9 12.5-4.2.2 8.2--50.0

p Value I

4 12 178

< 0.0001 0.4573 <0.0001

52 218

< 0.0001 < 0.0001

17.0

5.6-40.3

117

< 0.0001

68 26

2,047 <0.0001 < 0.0001 2,076 0.0116 2,077

53.2 29.1

6.4-63.9 12.2-35.8

106 36

< 0.0001 0.0003

21.9-84.9 9.4-37.3

215 113

< 0.0001 2,073 < 0.0001 2,076

55.8 36.8

29.7--00.6 15.6--50.6

51 86

<0.0001 < 0.0001

2,644 37.6 2,666

79.0

70.2-100 4.2-58.4 53.2-94.3

157 124 61

< 0.0001 2,076 < 0.0001 2,061 < 0.0001 2,076

86.4 18.0 75.5

69.4-100 2.1-42.6 56.4-95.2

103 113 67

< 0.0001 < 0.0001 < 0.0001

2,530 2,641 2,641

73.6 51.1 16.1

62.8-88.7 38.5--63.3 5.7-22.0

52 57 25

< 0.0001 1,972 < 0.0001 2,063 0.0153 2,047

42.9

74.4

45 33 42

< 0.0001

10.1

61.5-86.8 28.6-54.4 2.1-18.3

2,662 2,663

29.2 14.8

2.7-56.6 0.0--31.1

246 192

< 0.0001 2,075 < 0.0001 2,070

38.2 15.1

6.5--61.8 0.7--30.8

120

2,648 2,629 2,667 2,664 2,665 2,665 2,654 2,655 2,656

71.6 59.9 1.3 1.6 3.9 3.2 7.1 49.2 0.2

57.4-93.2 43.4-78.9 0.0--6.4 0.0--6.8 0.0--7.5 0.0--18.1 2.2-12.8 30.3-73.6 0.0--0.8

62 125 25 40 33 311 67 110 11

< 0.0001 2,062 < 0.0001 2,039 0.Gl56 2,073 < 0.0001 2,055 0.0011 2,071 < 0.0001 2,070 < 0.0001 2,073 < 0.0001 2,070 0.518 2,071

64.9 8.7 7.3 5.6 5.7 15.1 43.0 0.1

BO.O

70.0--91.4 43.8-78.4 0.0--17.9 2.0--17.5 0.0--13.6 0.0--18.3 3.2-24.4 22.9-68.7· 0.0--0.8

4B 58 52 54

113

42

153 86 118 15

0.0011

< 0.0001 < 0.0001 < 0.0001 < < < < < < < <

0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.2382

*Values are given as the percentage of subjects answering "yes," unless otherwise indicated. SABA = short-acting 1i2-agonist; GINA = Global Initiative for Asthma; LABA = long-acting ~2-agonist; LTRA = leukotriene receptor antagonist. tThe denominator upon which the proportion of each variable Is based. i'ltstatistics have 12 df (except household income and asthma severity, which have 24 df), since there were 13 adult and pediatric sites. For age, the F statistic from a one-way analysis of variance is presented in place of the >t statistic, and the corresponding df for numerator is 12 (for children and adults) with denominator df of 2,658 for children and 2,658 for adults. §Values are given as the mean. [Excludes patients who responded "do not know or prefer not to respond." Other numbers are less than the total sample of 2,671 children and 2,078 adults due to sporadic missing data.

sequent ED management revealed that substantial variations in care and gaps between current practice and evidence-based guidelines prevail across a representative sample of EDs in the most populated province of Canada. In addition, patient characteristics, including indices of socioeconomic status, 728

asthma severity, comorbidities, access to care, and asthma management preceding the ED visit varied considerably, Notable care gaps included lack of controller inhaler therapy prior to the ED visit, underutilization of objective measures of airflow rates in the ED, underutilization of systemic cortiOrIginal Re8eIrch

Table 3--A8thma Emcerbation Characteriatic. and ED Management (Chart Abstraction Data)* Pediatric Participants

Adults Participants I I

2

Variables Administrative Length of stay.] h Time to see doctor.t h Admitted to hospital Time to hospital admission.I h Presenting symptoms Shortness of breath Chest tightness Wheeze Cough Documented triggers Infection Allergen Irritant Physical examination Decreased LOC Respiratory distress Increased respiratory effort Exacerbation severity (CAEP/CTS) Mild Moderate Severe Near death Investigations Spo, documented PEFR CXR Blood gas measurements Management in ED Salbutamol MOl Nebulizer Ipratropium bromide MOl Nebulizer Systemicsteroids Oral IV

ICS Nebulizer MOl Epinephrine Antibiotics Oxygen Hospital discharge management Systemicsteroid ICS SABA LABA Spacer prescribed Education Inhaler teaching documented When to return to ED Trigger avoidance Smokingcessation PEFR monitoring

No.

Overall Site Range

X Statistic]

p Value

2,064 1,772 2,671 312

2.2 0.7 12.7 3.4

0.8-4.5 0.1-1.3 1.B-24.0 0.B-9.8

451 380 97 93

< < < <

2,669 2,670 2,666 2,670

65.7 10.9 41.6 73.5

44.1-88.8 3.0-45.3 26.3-79.1 60.1-83.3

129 324 244 66

< 0.0001 < 0.0001 <0.0001 <0.0001

1,733 1,584 1,585

88.3 9.5 6.9

70.4--93.8 5.4--18.5 1.4--33.3

28 30 62

2,668 2,668 2,668 2,438

0.4 15.6 28.6

0.0-4.4 3.0-68.7 3.8-44.0

0.8 57.9 34.7 6.6

0.0-9.2 25.8-92.0 6.0-00.9 1.4--21.1

2,671 1,032 2,669 2,671

94.7 27.2 30.7 0.5

72.3-99.6 0.0-61.8 9.4--43.3 0.0-6.4

2,669 2,668

15.2 61

0.0-69.1 3.3-87.3

2,666 2,666

10.3 33.6

0.0-59.7

2,668 2,668

2

No. Overall Site Range

X Statistic]

p Value

0.0001 1,808 0.0001 1,355 0.0001 2,078 0.0001 149

2.4 0.8 7.8 4.7

0.7-,'3.9 0.2-1.7 0.7-15.4 0.7-11.1

324 246 82 34

< 0.0001 < 0.0001 <0.0001 0.0003

2,076 2,077 2,075 2,077

79.8 29 40.5 61.5

47.5-97.1 13.1...Q3.9 18.5--76.5 41.4--85.1

126 257 375 111

< 0.0001 < 0.0001 <0.0001 < 0.0001

0.0064 1,184 0.0025 1,097 < 0.0001 1,097

74.1 14.1 16.1

54.1-94.1 5.4--40.0 4.3-30.9

53 72 41

< 0.0001 <0.0001 < 0.0001

25 470 170 299

0.0127 <0.0001 < 0.0001 < 0.0001

2,077 2,077 2,076 1,949

0.3 17.4 9.8

0.()...{).8 3.3-66.0 2.1-25.5

458

8

1.5 67.7 26.4 4.5

0.0-5.6 25.3-87.2 9.9-63.3 0.0-11.9

0.8088 < 0.0001 <0.0001 < 0.0001

172 142 106

< < < <

2,078 2,078 2,075 2,077

97.5 44.3 42.7 1.6

90.4--100 12.3-73.6 12.5-55.9 0.0-22.1

225

603

800

< 0.0001 2,076 < 0.0001 2,075

25.4 55.6

0.0-78.7 1.&-86.8

O.~.O

758 313

< 0.0001 2,073 < 0.0001 2,075

19.9 47.1

34.1 1.5

3.8-55.4 0.0-4.3

287 27

< 0.0001 2,077 0.0075 2,077

2,668 2,667 2,667 2,665 2,668

14.1 2.5 0.3 3.7 6.1

0.0-47.9 0.0-21.1 0.0-2.1

0.0-13.8

700 299 17 33 85

<0.0001 < 0.0001 0.1629 O.OOll <0.0001

2,314 2,308 2,309 2,309 2,309

31.7 22.2 24.7 0.3 13.3

3.1--50.0 11.2-56.0 8.1-44.0 0.0-3.0 3.0-32.0

196 97 43 14 61

2,667 2,303 2,297 2,293 2,302

10.5 42.2 2.7 1.4 0.2

0.0-24.9 2.3-90.5 0.0-9.7 0.0-15.9 0.0-3.0

203 546 37 112 26

o.o.n.r

48

0.0001 0.0001 0.0001 0.0001

121 309

35 252 61

0.0004 < 0.0001 <0.0001 < 0.0001

685

807

< 0.0001 < 0.0001

0.0-72.2 0.0-75.0

742 500

< 0.0001 < 0.0001

25.8 8

3.4--48.5 0.0-19.2

129 111

< 0.0001 < 0.0001

2,077 2,076 2,077 2,077 2,076

6.4 4 0.3 4.9 8

0.0-26.1 0.0-31.4 0.0-1.4 0.0-26.6 0.0-22.0

256 370 12 119 110

< 0.0001 < 0.0001 0.4436 <0.0001 < 0.0001

<0.0001 < 0.0001 < 0.0001 0.3049 < 0.0001

1,900 1,903 1,899 1,898 1,900

33.2 21.7 18.6 0.9 8.1

13.0-61.9 4.8-32.4 5.8-35.1 0.0-7.5 0.0-29.3

136 56

< 0.0001 < 0.0001 <0.0001 0.0013 <0.0001

<0.0001 <0.0001 0.0002 < 0.0001 0.0103

2,077 1,894 1,895 1,879 1,895

6.3 31.4 2.3 3.9 0.5

0.0-23.1 2.1-81.0 0.0-17.6 0.0-22.9 0.0-2.6

79

32 100

209 251

lOB

131 23

< < < <

0.0001 0.0001 0.0001 0.0001 0.0287

(Continued)

www.chestjournaJ.org

CHEST/135/3/ MARCH, 2009

728

Table 3-Continued Pediatric Participants No.

Variables Follow-up /referrals Documented With GP With current specialist New referral to specialist Other asthma service

2,321 2,321 2,309 2,309 2,307

Overall Site Range 55.6 49.2 3.8 1.8 2.8

Adults Participants I

t'

Statistic]

31.5-88.8 17.3--82.8 0.0-10.1 0.0-4.3 0.0-13.7

p Value

j

2

No.

Overall Site Range

< 0.0001 1,910 < 0.0001 1,910 < 0.0001 1,905

319

383 63 23

<

128

0.0311 1,906 0.0001 1,904

47.5 43.9 1.8 0.8 2.7

22.6--83.6 22.1-81.4 0.0-4.8 0.0-2.2 0.0-10.5

X

Statistic]

p Value

194 190 24 11

< 0.0001 < 0.0001

64

0.0212 0.5424 < 0.0001

*Values are given as the percentage answering "yes," unless otherwise indicated. MOl = metered-dose inhaler; Spo, = pulse oximetric saturation; LOC = level of consciousness; GP = general practitioner. See Table 2 for explanations of terms and for abbreviations not used in the text. PEFR excludes patients < 7 years of age, and the number of days of new systemic steroids is based patients prescribed new systemic steroids. Other numbers are less than the total sample of 2,671 children and 2,078 adults due to sporadic missing data. tx2 statistics have 12 df (except "Exacerbation severity," which has 36 df) and were estimated by the Pearson X2 test for all variables except for "Length of stay," "Time to see doctor," and "Time to hospital admission," which were estimated by the Kruskal-Wallis test. [Values are given as the median.

costeroids in the ED and on discharge, and very low referral rates to specialists and specialized asthma services. Use of steroids in the ED and on discharge was higher in urban than rural sites. Admissions and relapse rates at adult sites were associated with delay in receiving systemic steroids in the ED and lack of prescription of inhaled steroid on discharge, respectively. Knowledge translation initiatives are warranted to increase adherence with asthma guidelines, reduce

practice variations and improve outcomes of severe acute asthma. The identified gaps in care may be useful performance indicators for the hospital EDs. The multicenter design and large sample size are major strengths of the current study, and enhance generalizability. The response rate of 55%, although not surprising for such a complex study, is a limitation that introduces the possibility of some response bias. Nevertheless, the small but statistically signifi-

12 11

C W

E

,g

Pediatrics

Adults ::

10

9

=-

cu 8

E

o

::z::

CD

e'

III

'5

II)

i3

.s !::l o

7

=

8

=

5 4

3

::z:: 2

0"--

'--

--1

Sit. FIGURE 2. Box plots of length of stay in the ED by site in children and adults, sorted in ascending order of the value by site. The box represents the middle 50% of data (te, first to third quartile). the dash in the boxrepresents the median, whiskers represent the data range up to 1.5 times the interquartile range beyond the first and third quartiles; outliers beyond the whiskers are marked as dashed lines. A few extreme outliers faIl beyond the upper range of this figure.

730

Original~

100

Pediatrics

90

'a

~Gl E ::::l U

80

70

o

60

~ ii:

50

C

Adults

o.ll:

= a. 'f1.

40

30 20 10

0'--=-

'--

-'

Site FIGURE 3. Documentation of peak flow by site in children and adults. Site-specific percentages with exact binomial 95% confidence intervals are sorted in ascending order of the value by site. Documentation of PEFR in patients ~ 7 years of age.

cant differences between participants and nonparticipants in age, gender, and discharge diagnosis are not clinically relevant. The higher admission percentage in participant visits than nonparticipant visits in both

100

C

W

.5

.r-----------------;------------------,

90

c

80

C)

70

.~

age groups may reflect selection bias in that admission to hospital is indicative of a more severe exacerbation. However, since adherence with key components of asthma management such as PEFR

Pediatrics

Adults

~

~ 80

~50 II

'a )

40

U

E Gl

30

!

20

-.e.

10

0'-

--'-

---'

Sit. FIGURE 4. Documentation of systemic (oral or IV) steroid use in the ED by site in children and adults. Site-specific percentages with exact binomial 95% confidence intervals are sorted in ascending order of the value by site. www.chestjoumal.org

CHEST/135/ 3/ MARCH, 2009

731

100

CD es

90

.!!

80

~

70

ca

.s::. u

C

'Se'"

Pediatrics

Adults

'U

fI)

! o

i . U

.5 o 'U

:9 .... 'f1.

80

50

40 30 20

10

OL.-

----'

Sit. FIGURE 5. Documentation of systemic (oral) steroid prescription on discharge by site in children and adults. Site-specific percentages with exactbinomial 95% coD.fidence intervals are sorted in ascending order of the Value by site. Values includeincreasein previous dose or newprescription of oral steroid.

measurement, systemic steroid use in the ED and on discharge, and referrals to specialized asthma services were significantly higher in individuals with more severe CTAS asthma severity classification and in admitted patients (data not shown), the differences in admission percentage would have, if anything, underestimated the care gaps noted. Although use of 2002 data to make inferences regarding current ED management is also a potential limitation, subsequent research has revealed minimal differences in ED practice patterns since this study was conducted.P-" Similarly, control of ambulatory asthma in Canada has been unchanged from the late 1990s until at least the mid-2000s.2.22-24 The sampling framework-" of this study was such that these results are likely more generalizable within Canada and the Unites States than are results from Single-center studies-" or studies focusing on care in academic centers.I" The finding that only 76% of children and 81% of adults received salbutarnol in the ED is consistent with previous studies15,16 and raised concern about possible diagnostic misclassification (ie, inclusion of nonasthma cases). However, the re-abstracted data suggested this was not the case. Accuracy of chart abstractions for ED asthma care has been studied by McDermott et al.25 Chart review exceeded direct observation of management for several key aspects of assessment (including documen732

tation of peak flow and oxygen saturation), treatment (such as prescription of oral steroids on discharge), and referrals. They also noted good agreement on many other items including use of systemic steroids and ~-agonists in the ED, but poor agreement between chart review and direct observation for education delivered in the ED. In the current study, subgroup analyses of children (5 to 19 years of age) and adults (20 to 39 years of age) revealed minor differences in patient characteristics (apart from comorbidities and age, as expected) and their ED management (apart from CXRs being done less commonly when children < 5 and adults > 40 years of age were excluded) in comparison to the entire sample. Furthermore, site heterogeneity of each subgroup was comparable in magnitude and statistical significance to the entire pediatric and adult samples. Limiting the analysis to the first visit with a corresponding questionnaire avoided statistical complexities due to within-patient dependence but could have introduced bias since patients with repeat visits may have different characteristics (such as more severe asthma)19,26 and/or may have had their asthma suboptimally managed during their first visit. However, analysis of all visits yielded results very similar to first visit results. Since almost all of the p values are highly significant, reasonable adjustments for multiple compariOrIginal R-m

100

8

90

rI

80

~

III

E

70

.!! '""

60

ii

50

8.

40

5

j

·u

en S

~

!

'i!-

Adults

Pediatrics

30

20

10 o'---=-~

-'--

-----'

Sit. FIGURE 6. Documentation of referral to specialized asthma services (asthma specialist or asthma education center) on discharge by site in children and adults. Site-specific percentages with exact binomial 95% confidence inteivalS are sorted in ascending order of the value by site. Values include follow-up arrangements documented with regular ~, new referral to specialist or other specialized asthma service (eg. asthma educator, asthnla education center or clinicy'

sons27•28 have little impact on the conclusions. All of the reported unadjusted p values < 0.05 from Tables 2 and 3 have an FDR (ie, a probability of being a type I error) < 5%, according to the FDR approach of Benjamini and Hochberg.s? In particular, the largest p value < 0.05 is 0.0311, which has an FDR of 3.32%, and the other FDRs are nearly identical to the reported unadjusted p values. If we consider Tables 4 and 5 together, but separate from Tables 2 and 3, then only the p values < 0.01 have an FDR < 5%. If we consider all p values from Tables 2 through 5 together, then the FDR is only trivially larger than the reported unadjusted p values, and all p values < 0.04 have an FDR < 5%. This study documented variations in sociodemographic variables, asthma history, asthma severity, co-morbidities, triggers and exposures in the home, access to care, health-eare utilization, and management preceding the ED visit, which may independently contribute or interact to influence outcomes such as ED visits and hospitalization. The demographics and chronic asthma history, smoking history, and management are comparable to those describe in previous publications from the Multicenter Airway Research Collaboration, involving 21 states in the United States and 4 Canadian provinces.29 •30 In light of the recognized adverse effects of www.chestjoumal.org

smoking on lung function and medication efficacyin asthma,31.32 the prevalence of comorbid COPD and second-hand smoke exposure in this study suggest that smoking cessation and public health measures to control environmental tobacco smoke exposure are warranted. Infections were the most commonly cited trigger for the index exacerbation, suggesting strategies to prevent respiratory tract infections merit investigation. Variations in access to care may influence attendance at an ED for care as well as an ED health-care provider's decision to admit or discharge a patient. Given that up to 30% of visits at some sites were by individuals who did not have a regular physician for asthma care, improved access to primary care practitioners and chronic disease management programs may reduce ED visits and hospitalizations for asthma. Similarly, up to 25% of visits at some sites were by individuals without a drug insurance plan, which is a recognized barrier to optimal asthma control.33 Only a minority of individuals had ever received asthma education, and written asthma action plans were almost nonexistent. Furthermore, comparison of the proportion of ED visitors with doctor-diagnosed asthma (76 to 84%) and the proportion on an inhaled corticosteroid (ICS) prior to the ED visit (60 to 65%) CHEST/ 135 / 3 / MARCH, 2009

733

.....

I

::I.

i

o

~

7)

23.4 ± 17.5 15.3 ± 6.4 2.0 ± 0.7 25.8 ± 12.0 14.1 ± 8.4

2.0 ± 0.4

21.5 ± 7.1

37.5 ± 8.8

12.7 ± 6.5 4.3 ± 4.0

Rural (n = 6)

25.7 ± 17.5 41.8 ± 11.4

12.7 ± 6.1 5.5 ± 0.3

=

Urban

(n

---

Rural

20.7 ± 7.6

38.8 ± 10.0

38.7 ± ILl

29.5 ± 12.0 0.097

- 1.82

38.8 ± 9.5

26.0 ± 13.2

21.5 ± 8.8

22.0 ± 0.4 0.158 1.52

18.6:t 0.3

25.9 ± 9.6

1.7 ± 0.3

1.9 ± 0.6 0.998

0.00

2.0 ± 0.5

2.0 ± 0.5

50.0 ± 12.6 35.6 ± 6.6

40.0 ± 19.1 31.6 ± 15.9

0.45 0.496

0.78 - 0.70

20.8 ± 17.0 38.9 ± 11.7

28.9 ± 17.2 32.5 ± 17.5

4.1 ± 1.6 5.3 ± 3.5 10.3 ±.4 3.0 ± 2.8

0.043 0.103

2.29 - 1.78

0.003

-3.79

- 1.29

0.12

0.73

- 0.98 - 0.51

2.40 -1.21

- 2.91

- 0.83

19.1 ± 4.5

22.9 ± 7.6

0.499

0.70

0.224

0.906

0.480

0.348 0.617

0.035 0.252

0.014

0.425

0.341

-1.00

0.940 0.937

1.5 :t 0.5

1.9 ± 0.4

49.7:t 12.7 39.4 ± 7.5

1

P Value

0.098 0.005

t Test] (df= 11)

- 1.81 - 3.47

= 9)

31.4 ± 20.1 18.8 ± 11.6

(n

Teaching Hospital (n = 4)

0.08 -0.08

(n = 6)

Community Hospital

Adult Sites

7.9:t 6.3 3.9:t 2.9

7.6 ± 4.7 4.1 ± 3.5

Urban (n = 7)

.-

0.978

0.858 0.004

0.994 0.743

P Value

I

0.03

- 0.18 - 3.61

- 0.01 - 0.34

t Test] (df = 11)

8.9 ± 1.8 7.8 ±.7

Teaching Hospital (n = 4)

15.9 ± 6.7 3.0 ± 3.0

Community Hospital (n = 9)

Pediatric Sites

·Values are given as the mean ± SD, unless otherwise indicated. tlndependent t test of site averages weighted by number of participating patients at site.

PEFR documented, % Systemic steroids administered in ED, % Time to systemic steroid administration. h Inhaled steroid administered at hospital discharge. % Systemic steroid administered at hospital discharge. % Site setting Admitted to hospital, % Repeat ED visits within 28d,% PEFR documented. % Systemic steroid administered in ED, % Time to systemic steroid administration, h Inhaled steroid administered at hospital discharge, % Systemic steroid administered at hospital discharge, %

28d. %

Site size Admitted to hospital. % Repeat ED visits within

Variables

I

Table 4--Comparison of ED Management and Outcomes by Site Characteristics*

Table 5--Correlationa Between Site-Level Health-Care Utilization and ED and Hospital Diacharge Management Pediatric Sites (n = 13) Variables Hospital admission Systemic steroids administered in ED Time to systemic steroid administration in ED PEFR documented in EDt Repeat ED visits within 28 d New ICS administered on hospital discharge New systemic steroid administered on hospital discharge

I

Adult Sites (n = 13) I

r Value*

p Value

0.35 0.22 -0.06 - 0.44 0.13

I

I

r Value*

p Value

0.237 0.49 0.851

0.57 0.76 - 0.23

0.043

0.136 0.670

- 0.64 0.44

0.OI9 0.137

(J.(X14

0.446

*Correlatioll of site averages weighted by the number of visits. tvalues are based only on patients 2: 7 years of age.

suggests that up to 25% of these patients were not receiving therapy according to guideline recommendations. 5 .9 Under treatment of asthma in children preceding ED visits has also been reported in the United States34 and is a recognized risk factor for recurrent ED visits.35 Ontario's Asthma Plan of Action;" particularly the Primary Care Asthma Program and the Ontario Lung Association's Asthma Provider Education Program.F may address these gaps in primary care. The most notable gaps in ED care were: (1) underutilization of spirometry or PEFR to either assess the severity of the exacerbation at presentation to the ED or to assess suitability of discharge home; (2) underutilization of systemic steroids both in the ED and on discharge; and (3) failure at the time of discharge to refer the majority of these high-risk individuals to specialized asthma services. Although guidelines do not recommend routine CXRs, they were done in 30 to 43% of cases-on average, as often as or more often than PEFR measurements. Improvement in this aspect of the management of severe acute asthma may reduce the costs incurred by potentially unnecessary investigations and improve resource allocation. The care gaps noted are substantially larger than a recent report of Canadian centers participating in the Multicenter AiIway Research collaboration'" and are likely more representative of average Canadian EDs. Of particular concern are the considerable practice variations between centers, an observation not previously reported. If use of steroids and referrals could be increased, patient outcomes and relapse rates might improve.3B Reasons for the variations in care gaps between institutions are not known. Potential explanations include regional differences in access to services (such as spirometry in the ED or specialists in the community), knowledge of emergency asthma management guidelines and recent literature, the presence of standardized order sets and automatic referrals, and attitudes and beliefs of health-care www.chestjoumal.org

providers regarding aspects of care such as the merits of education in ED and indications for referral. The correlation between various management practice patterns (eg, systemic steroids in ED, systemic steroids on discharge, and use of PEFR) suggests certain sites were performing better in general. Multilevel modeling that controls for potential confounders is warranted to determine patient, site, and management characteristics associated with the best outcomes. In conclusion, despite publication and revision of national and international guidelines, significant gaps persist in emergency management of asthma. ll •14 ,19,39 Although the magnitude of care gaps varied among hospitals, the prevalence and magnitude of these gaps-such as underutilizationof objective measures of airflow obstruction, underutilization of systemic steroids, and failure to refer to specialists-suggest a common and widespread need for successful knowledge translation initiatives, such as clinical pathways that support best practice,33.40.41 to enable adherence with guidelines,optimize resource use, reduce morbidity, and improve health. ACKNOWLEDGMENT: We thank site investigators (Drs. Michael de la Roche. Don Koval, and Elizabeth Powell) and site coordinators (Mr. Lucio Fabrio, Ms. Vanessa Lamarche, and Mr. Randy Penny) for their collaboration; and Ms. Yingua Su and Ms. Miao Wang of the Kingston General Hospital Clinical Research Centre for assistance with data analysis.

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