OBJECTIVE: To assess the effectiveness of nurse-initiated administration of oral corticosteroids before physician assessment in moderate to severe acute asthma exacerbations in the pediatric ED.
METHODS: A time-series controlled trial evaluated nurse initiation of treatment with steroids before physician assessment in children with Pediatric Respiratory Assessment Measure score ≥4. One-to-one periods (physician-initiated and nurse-initiated) were analyzed from September 2009 through May 2010. In both phases, triage nurses initiated bronchodilator therapy before physician assessment, per Pediatric Respiratory Assessment Measure score. We reviewed charts of 644 consecutive children aged 2 to 17 years for the following outcomes: admission rate; times to clinical improvement, steroid receipt, mild status, and discharge; and rate of return ED visit and subsequent admission.
RESULTS: Nurse-initiated phase children improved earlier compared to physician-initiated phase (median difference: 24 minutes; 95% confidence interval [CI]: 1–50; P = .04). Admission was less likely if children received steroids at triage (odds ratio = 0.56; 95% CI: 0.36–0.87). Efficiency gains were made in time to steroid receipt (median difference: 44 minutes; 95% CI: 39–50; P < .001), time to mild status (median difference: 51 minutes; 95% CI: 17–84; P = .04), and time to discharge (median difference: 44 minutes; 95% CI: 17–68; P = .02). No differences were found in return visit rate or subsequent admission.
CONCLUSIONS: Triage nurse initiation of oral corticosteroid before physician assessment was associated with reduced times to clinical improvement and discharge, and reduced admission rates in children presenting with moderate to severe acute asthma exacerbations.
- CI —
- confidence interval
- ED —
- emergency department
- PRAM —
- Pediatric Respiratory Assessment Measure
- URTI —
- upper respiratory tract infection
What’s Known on This Subject:
Early administration of oral corticosteroids is essential for children presenting to emergency departments with moderate to severe acute asthma exacerbations, because subsequent admission need is directly related to time to receipt of systemic steroids, yet delays to administration remain long.
What This Study Adds:
A medical directive allowing nurse initiation of oral corticosteroids before physician assessment was associated with improved quality and efficiency of care provided in the pediatric emergency department by ensuring implementation of evidence-based practice.
Early administration of oral corticosteroids can reduce hospital admission for children presenting to emergency departments (EDs) with asthma exacerbations.1,2 Improving efficiency in asthma management is an essential element of relieving ED overcrowding, attributable in part to suboptimal flow, because asthma is the most prevalent childhood chronic disease requiring ED visits.3–5 Despite evidence supporting their need, physicians underprescribe corticosteroids for children, and delays to administration remain long.2,6–9
Utilization of the full complement of skills and competencies of health care providers may play an important role for improving efficiency in the ED.10,11 Medical directives (collaborative protocols allowing nurse initiation of treatment before physician assessment) have the potential to improve productivity and promote implementation of evidence-based practice.12 Future asthma clinical pathways should include a focus on optimizing flow in the ED.9 ED nurses and allied health team members commonly initiate medication such as bronchodilator (β2-agonist and inhaled anticholinergic) therapy before physician assessment.13 This study investigated the effect of pediatric triage nurse initiation of oral steroids before physician assessment on hospital admission rates and time to clinical improvement.
We performed a time-series controlled trial (before and after initiation of a medical directive permitting triage nurse initiation of oral steroids) with a 1:1 ratio of time periods: physician-initiated phase (4 months) and triage nurse–initiated phase (4 months). Ethics approval was obtained from the local research ethics board. Because this study was an assessment of a practice change, informed consent was deemed unnecessary. Through all stages of this work, we followed a protocol developed by the coauthors before study initiation; all outcomes and analyses were specified a priori. ED physicians and nurses, apart from the coinvestigators (who represent 3 of the 44 physicians working in the ED), were unaware of the study.
Study Setting and Population
The setting was the ED of a tertiary children’s hospital with an approximate annual caseload of 60 000 children and 2500 asthma-related visits per year. All children aged 2 to 17 years presenting during the study period with a moderate to severe acute asthma exacerbation (Pediatric Respiratory Assessment Measure [PRAM] score ≥4) were eligible.14 The validated PRAM score discriminatively measures severity, with a range of 1 to 12 points.15 Asthma was defined as previous physician diagnosis or third or greater episode of wheezing responsive to β2 agonists, consistent with the Canadian Pediatric Asthma Consensus Guidelines and the Global Initiative for Asthma guidelines.16,17
Existing Standard of Care
Our ED used a medical directive permitting triage nurses to initiate bronchodilator therapy before physician assessment for more than a decade. In 2008, the PRAM score was embedded into the directive, in which severity dictated management. The PRAM score has demonstrated good interuser reliability among professions.14 Children with mild exacerbations (PRAM score ≤3) were initiated on hourly salbutamol treatment administered through a metered-dose inhaler. Children with moderate exacerbations (PRAM score of 4–7) received 3 salbutamol treatments by metered-dose inhaler during the first hour and continued hourly treatment as needed. Children with severe exacerbations (PRAM score ≥8) received 3 salbutamol plus ipratropium bromide nebulizations for the first hour and continued hourly salbutamol treatment as needed. Physicians were encouraged to prescribe oral corticosteroids for patients with moderate and severe exacerbations.
Development of Pathway
A multidisciplinary team developed a medical directive creating a provision for triage nurses to initiate oral dexamethasone treatment before physician assessment to children presenting with moderate to severe asthma exacerbations per triage PRAM score (Appendix 1). The purpose of the directive was to safely administer systemic steroids early in the ED visit. Excluded from eligibility were children with the following: chronic lung disease (eg, bronchopulmonary dysplasia, cystic fibrosis); chronic cardiac, metabolic, or neuromuscular disorders; those who had undergone tracheostomies or in whom treatment with steroids or inhaled β2 agonists was contraindicated (eg, patients on β-blockers or those with known hypersensitivity to salbutamol, ipratropium bromide, or dexamethasone, or a history of adrenal suppression);those who had exposure to varicella in the preceding 3 weeks, in the absence of immunization; those who required immediate life-sparing resuscitation; and those who had received treatment with oral steroids in the previous 14 days.
Our institutional process for the development and approval of medical directives was followed for implementation (Appendix 2). Representatives from nursing, pharmacy and physicians provided expert opinions.
Sample Size Estimation
We reviewed ED visits between April 2006 and March 2008 by patients aged 1 to 18 years for urgent and emergent asthma (International Classification of Diseases, 10th Revision codes J45.0–J45.91). Truncating visit length at 6 hours, the standard deviation of visit length was 1.96 hours. Fixing probability of type I error at .05, a sample size of 242 patients per group would provide 80% power to detect a decrease in time spent in the ED of 30 minutes. By using census data from the preceding 2 years, we calculated the need to screen 1100 charts for eligibility, divided into two 4-month periods.
The study had before and after phases. The physician-initiated phase (before) comprised 4 months immediately before the introduction of the medical directive (September 2009–December 2009). During the physician-initiated phase, patients received standard care: triage nurse assessment of severity with initiation of bronchodilator therapy before physician assessment when indicated by PRAM score, with subsequent hourly measurements. Systemic steroids were given only after physician assessment and ordering.
The nurse-initiated phase (after) comprised the 4 months subsequent to implementation (February 2010–May 2010). A 1-month training period (January 2010) separated the phases and was used for training. Data from this period were not considered in the analysis. There were no changes in documentation or assessment frequency during either study period. Other than the triage document, we are not using an electronic medical record in our ED.
The primary outcome was time to clinical improvement. Operationally, time to clinical improvement was defined as time spent in the ED between arrival and a persistent reduction of the PRAM score by ≥3 points over 2 assessments.15 Secondary outcome measures were as follows: total time in ED, admission rate, time to mild status (defined as PRAM score persistently ≤3, indicative of overall improvement in discharged patients), and ED return visits for asthma over 7 subsequent days.
Data were collected on potential confounders such as previous hospitalizations, age, concurrent viral illness (ie, upper respiratory tract infection [URTI]), tobacco smoke exposure, and degree of severity at presentation. All cases with International Classification of Diseases, 10th Revision discharge diagnosis of asthma during the study period were reviewed to identify eligible cases. Data were extracted by chart audit by using standardized forms. Given the complex nature of the ED (where nurses are responsible for the care of several patients plus patients requiring resuscitation), we expected minor time deviations from exact hourly timing of PRAM scores, so actual time was recorded rather than by using discrete hourly intervals. The principal investigator trained 2 reviewers. To ensure data were complete and valid, the time between each consecutive measurement was computed, and range checks were used to detect discrepant values. To ensure reliability, the primary investigator oversaw initial data collection for both reviewers and was available for questions during data collection. Patient characteristics were extracted from the medical chart. We assessed interrater reliability of chart abstractors by duplicate sampling of 5% of included charts for quality control.16,17 There was 100% agreement for date of birth, triage time, discharge status, admit to floor, and ICU. There was excellent interrater reliability for previous hospital admission (κ = 0.83), initial PRAM score (κ = 0.96), and PRAM-2 score (κ = 0.99). The only moderate κ value was for presence of preceding URTI (κ = 0.56).
Patient characteristics were summarized for patients overall and by phase. Discrete variables were summarized by using frequencies and proportions. Continuous variables were summarized by using means and standard deviationss. Comparisons of discrete variables between phases were made by using Pearson’s χ2 or Fisher’s exact test, as appropriate.
In the time-to-event analyses, censoring occurred for admission before clinical improvement. Time to clinical improvement before and after implementation was examined by using Kaplan-Meier curves and compared by using log-rank test. Median time to clinical improvement before and after implementation was computed, and 95% confidence intervals (CIs) for their differences were obtained based on 1000 bootstrap replicates.18 Comparisons of continuous variables in baseline characteristics were made by using Student’s t test or Wilcoxon rank-sum test, as appropriate. Patient characteristics found significant at the 2-sided P = .10 levels were included in adjusted analysis by using Cox proportional hazards regression.19 The Kaplan-Meier curves were plotted on log scale to verify the assumption of proportional hazards.
7During the study period and excluding the 1-month training period, staff in the ED treated 1183 cases of acute asthma. Of these cases, 644 were classified as moderate to severe (physician-initiated phase = 336, nurse-initiated phase = 308; Fig 1).
We compared patient characteristics for both phases (Table 1). The children were similar in age, gender, and previous asthma severity based on previous hospitalization rates. Children in both phases had similar durations of respiratory distress preceding presentation. The physician-initiated phase had a higher proportion with preceding URTIs. Most patients in both groups were treated with salbutamol before arrival, with a slightly greater proportion of patients in the nurse-initiated phase having documented preceding salbutamol, chronic inhaled corticosteroid, and oral montelukast use.
On arrival at triage, patients in both phases demonstrated similar vital signs. The mean initial PRAM score at triage of eligible patients was 6.7 (SD = 1.8, moderate). Other than timing of oral steroids, children were treated similarly while in the ED (Table 2). Finally, although total ED caseloads during study phases were approximately equal (19 805 total ED cases during the physician-initiated phase versus. 19 883 total ED cases during the nurse-initiated phase the physician-initiated phase had median ED length of stay 1 hour shorter than the nurse-initiated phase (2.7 hours vs 3.7 hours).
Children in the triage nurse–initiated phase improved significantly earlier compared with those in the physician-initiated phase, with a median difference of 24 minutes between phases (95% CI: 1–50 minutes; 158 minutes [interquartile range: 139–177] vs 182 minutes [interquartile range: 168–202]; P = .04; Fig 2). An adjusted analysis was performed because of differences in baseline characteristics between phases. A Cox regression of clinical improvement by phase, adjusting for differing variables (preceding URTI; use of salbutamol, oral montelukast, or chronic inhaled corticosteroids; and previous ICU admission) yielded the same effect (P = .05). Forty-one patients were admitted before PRAM score improvement ≥3, so they were censored in the analysis (median time to censoring was 536 minutes in physician-initiated vs 593 minutes in nurse-initiated phase). We performed a time-series analysis looking for trends toward shorter time to clinical improvement to confirm that our results were related to intervention rather than overall unrelated trends. We placed simple regression lines separately to the data in phases 1 and 2; there was a nonsignificant (P = .64) increasing trend in phase 1 and a nonsignificant (P = .28) decreasing trend in phase 2. That the direction of trend differs between the 2 phases suggests that there is no overall trend (Supplemental Fig 3).
Significant efficiency gains were associated with the nurse-initiated phase (Table 3). Hospital admission was significantly less likely, children received steroids faster, children improved to mild status faster, and they had an earlier time to discharge compared with children in the physician-initiated phase. There was no detectable difference in return rate to ED or subsequent admission in the 7-day period after the index visit. The adjusted analyses used to account for differing baseline characteristics yielded results at similar levels of statistical significance (Table 3).
Compared with usual care, a novel medical directive permitting nurse initiation of oral corticosteroids before physician assessment was associated with reductions in time to improvement, time to reach mild status, time to discharge, and risk of inpatient admission for children presenting with moderate to severe acute asthma exacerbations. Given the current ED overcrowding crisis, it is essential to find efficiency gains. The nurse-initiated steroid medical directive improved interprofessional productivity of the ED team by empowering nurses to provide asthma care in a manner more fully in keeping with their competencies and improving the standard of care for children presenting with moderate to severe asthma exacerbations.
Nurse-initiated treatments before physician assessment have been effective among emergency conditions, ranging from thrombolysis in myocardial infarction20 to analgesia for pediatric injuries.21 Standardized clinical pathways also have been shown to reduce admission rates twofold in asthma and threefold in general in the ED.8,22 Our novel intervention was associated with reduced admission rates. It is essential to note that physician ordering of systemic steroids already had been optimized at 94%. Again, the objective of this novel medical directive was to improve efficiency of the timing of steroid administration, not to simply improve adherence to guidelines. Our medical directive optimized the scope of practice for nurses and was associated with reduced burden of illness for children and the ED.
Proposed Reasons for Benefit
There are several reasons why the nurse initiation of systemic steroids may be beneficial. First, physicians may base key management decisions on the pharmacokinetics of the systemic steroids. Scarfone et al23 showed no clinical difference between placebo and oral corticosteroids after 2 hours, yet most children receiving oral corticosteroids were able to be discharged safely at 4 hours. The decision to discharge or admit may be delayed until the time steroids are considered to be effective. Physicians often postpone discharge the first time patients achieve mild status (especially if patients initially were in severe distress) to confirm that their treatment intervals can be stretched from hourly to every 90 to 120 minutes between rescue treatments. The medical directive does not make recommendations regarding the decision to discharge or admit or the timing thereof. A decision to admit usually is made only when the physician realizes that the child is not well enough for discharge (typically 4–6 hours into ED care). Dual delays in both assessment and initiation of treatment with systemic steroids will be compounded until disposition decisions are made. With the medical directive, children received their steroids 44 minutes earlier. This time savings translated into efficiency improvements in care process and clinical outcomes.
Another factor contributing to improvements was that our team had past experience using a multidisciplinary approach to asthma through a medical directive permitting bronchodilator initiation. This directive used PRAM scores in triage decision-making for initiation of bronchodilator therapy and ensured that nurse decision-making capacity was based on a validated and reliable tool while allowing decisions to be made within their scope of practice. Unanimity further reinforced cooperation: physicians unanimously approved, and no nurses refused to apply the medical directive. It has been well accepted by both doctors and nurses as an opportunity to potentially improve efficiency. All of these elements were necessary, given the enhancement of nursing practice that this medical directive sanctioned.
Our study does have some methodologic limitations. This study was not a randomized controlled trial; we can only report on associations between outcomes and intervention. In addition, lack of randomization introduced slight baseline characteristic differences between groups, although we performed adjusted analysis and obtained similar results. Data were collected from chart extraction rather than prospectively in the ED, possibly introducing risk of measurement error and dependence on nursing and physician documentation; however, measurement of the PRAM score (on which the primary outcome was based) was consistently recorded hourly, as indicated in the medical directive, and our outcome measures were well documented in the charts. We also confirmed times of patient arrival, discharge, and admission by referencing our electronic patient-tracking system database.
Another limitation was the sampling period: we selected consecutive cases 4 months before and after beginning the nurse-initiated medical directive; our study would have been stronger with more comparable periods. Seasonal variation exists, not only in potential asthma triggers,24 but in ED operations and resident maturation in academic settings.25 Ideally, the study would have used the same months in consecutive years. The chosen periods allowed for as similar a comparator as possible within our situation, in which we could not delay implementation of the directive (for operational reasons) and did not have a directly comparable period the year before because of ED renovations that resulted in improvements to patient flow and efficiency of care.
Although we identified several potential confounders, there are undoubtedly other unmeasured confounders related to seasonal variability between phases (eg, virus-type responsible exacerbation). The physician-ordering phase comprised fall and early winter months, whereas the nurse-initiated phase comprised late winter and spring months. This timing might explain group differences for URTI symptoms preceding the ED visit. Differences in frequency of viral infection potentially could influence patient response to oral corticosteroid therapy.26 Although seasonal variations of asthma triggers occur, until new literature clarifies determinants of oral corticosteroid responsiveness in pediatric children with asthma, the current recommended treatment is early administration of systemic steroids regardless of trigger, according to national and international guidelines.27–29 Finally, total ED caseloads over study phases were approximately equal, yet the physician-initiated phase had median ED length of stay 1 hour shorter than the nurse-initiated phase, rendering 44-minute savings in a more overcrowded department noteworthy. It is possible, however, that ED efficiency is an effect modifier; triage administration may result in different improvements when the system is overcrowded than when it is operating efficiently. Unfortunately, this possibility cannot be tested using the data available.
Our medical directive permitted nurse initiation of dexamethasone orally as compared with commonly used prednisone or prednisolone. The choice of dexamethasone was pharmacy-driven, owing to lower cost and lack of a low-cost palatable prednisone-based oral liquid at the time of the study. The literature has shown both dexamethasone and prednisone to be effective, with neither being clearly superior.30–32
A potential concern raised by medical directive use was the need for nurse determination of eligibility before physician confirmation of asthma diagnosis. Because only 1 nurse measured triage PRAM scores, we are unable to confirm if there was incorrect application of the medical directive, introducing the possibility of overapplication or underapplication. Misapplication of the medical directive is unlikely to be common, however, given good interobserver agreement of PRAM scores.15 Although the possibility of misapplication is relevant, given the potential toxicity of corticosteroids, confirmation of asthma diagnosis is also difficult for physicians in the busy ED, and there is no evidence that physician assessment is superior to a nursing assessment using a history of physician-diagnosed asthma or repeated wheezing episodes consistent with typical asthma symptomatology.22,33 Given efficiency gains associated with our medical directive and the limited literature investigating other nurse-initiated therapies, future directions should evaluate the efficacy of medical directives in other pediatric acute conditions.
We have shown that early initiation of treatment with oral steroids by ED triage nurses was associated with decreased lengths of stay and reduced hospital admission rates in children with moderate to severe acute asthma. Widely adopted, this strategy could optimize the function of multidisciplinary teams and have a significant impact on the burden of asthma in EDs.
Appendix 1: Medical Directive: Initial Oral Dexamethasone Therapy by Nurses for Known Asthmatic Patients With Moderate to Severe Respiratory Distress in the ED
Name of the medical directive: Initial oral dexamethasone therapy by nurses for known asthmatic patients with moderate to severe respiratory distress in the ED.
Name of contact person: Medical Director, Emergency Patient Service Unit
Area of practice: ED
Purpose statement: This medical directive allows nurses to administer an oral corticosteroid dose to patients admitted to the ED with a history of asthma presenting with moderate to severe asthma exacerbations. Oral corticosteroids are the gold standard of treatment for children and adults presenting with moderate to severe asthma to the ED, reducing by 25% the risk of hospital admission when they are administered within an hour of triage. This will allow the initiation of therapy for patients with moderate to severe asthma exacerbations before assessment by the physician. Dosage of medication will be dictated by the patient’s weight. Patient eligibility will be determined by the patient’s PRAM score on arrival to the ED.
Specific patient criteria: All patients in the ED with asthma meeting the inclusion/exclusion criteria will be started on the asthma critical pathway and will be treated in conjunction with the initial bronchodilator medical directive.
Authorized to registered nurses hired in the ED.
Alert and oriented
Aged 1 to 17 years
History of asthma with the use of bronchodilator(s) for previous exacerbations
Triage PRAM score of 4 to 11
PRAM score <4
Canadian Triage and Acuity Scale Level 1 (Resuscitation) or PRAM = 12
Hypersensitivity to dexamethasone or oral corticosteroids
Patients meeting any exclusion criteria from the asthma critical pathway
Patients with respiratory conditions such as bronchopulmonary dysplasia and cystic fibrosis
Patients with cardiac, metabolic, or immunologic disease or a history of adrenal suppression
Patients with coexisting acute illness such as pneumonia, pertussis, or croup
Any use of oral corticosteroid in the past 14 days
Exposure to varicella in the previous 3 weeks in a susceptible child
Description of procedure
a. Identify patients in the ED with breathing difficulties and a history of asthma, as per the asthma critical pathway inclusion/exclusion criteria
b. Complete a respiratory assessment by using PRAM (see below) and baseline vital signs, and document on the asthma critical pathway and/or triage document
c. Weigh the patient and document on the asthma critical pathway and/or triage document
d. Determine the appropriate Canadian Triage and Acuity Scale and treatment regimen based on the patient’s PRAM
PRAM score of 1–3: Patient will be managed per the initial bronchodilator medical directive only.
PRAM score of 4–11: Patient will be managed per the initial bronchodilator medical directive and receive 1 dose of oral dexamethasone (0.3 mg/kg per dose, with maximum dose of 12 mg). The dose of dexamethasone will be given immediately after the first bronchodilator treatment and before the second dose of the initial 3 back-to-back bronchodilator treatments. (Specifically, the patient will receive the first inhaled treatment, then oral dexamethasone, then the second inhaled treatment, and then the third inhaled treatment.)
PRAM score of 12: Notify physician immediately.
e. Any questions regarding the appropriateness or dosage of dexamethasone should be discussed with the physician before administration.
f. If at any time the patient no longer responds appropriately to treatment or deteriorates, immediately notify the physician.
Quality management process
All nurses will be educated about the purpose, indications, contraindications, and possible complications for administration of oral corticosteroids by the clinical educator or delegate.
All incident reports related to the administration of oral corticosteroids under this medical directive will be reviewed by clinical educator, operation director, and physician involved with care of the patient.
Audits will be conducted periodically to ensure that the medical directive is being used appropriately.
Consent and documentation
Verbal consent will be obtained from the patient/parent before administration of the medication. In keeping with “charting by exception,” the nurse will document only a refusal of consent/medication administration obtained from the parent.
Documentation of the medication will be made in the ED clinical record and/or asthma clinical pathway.
From the policy on the development and approval of Medical Directives, March 2008 (Reprinted with permission from the Children's Hospital of Eastern Ontario).
Appendix 2: Process for Development and Approval of Medical Directives
- Accepted December 5, 2011.
- Address correspondence to Roger Zemek, MD, Children’s Hospital of Eastern Ontario, Division of Pediatric Emergency Medicine, 401 Smyth Rd, Ottawa, ON, Canada K1H 8L1. E-mail:
Drs Zemek, Plint, Osmond, and Kovesi and Ms Correll contributed to study concept and design; Mr Perri contributed to acquisition of data; Drs Zemek, Plint, Osmond, Kovesi, and Barrowman provided analysis and interpretation of data; Drs Zemek and Barrowman drafted the article; Drs Zemek, Plint, Osmond, Kovesi, and Barrowman and Ms Correll and Mr Perri performed critical revision of the article for important intellectual content; and Dr Barrowman performed statistical analysis. Dr Zemek had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. The contents of the article are solely the responsibility of the authors.
FINANCIAL DISCLOSURE: Dr Kovesi has received honoraria and/or educational grants from AstraZeneca Canada, Merck Frosst Canada, and Nycomed Canada; the other authors have indicated they have no financial relationships relevant to this article to disclose.
FUNDING: Supported by the Ontario Academic Health Science Centers Alternate Funding Plan Innovation Fund.
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- Copyright © 2012 by the American Academy of Pediatrics