Promises and pitfalls in the evaluation of pediatric asthma scores

Validation of the Spanish version of the Pediatric Asthma Severity Score (PASS) in a population of Hispanic children

BACKGROUND

The Pediatric Asthma Severity Score (PASS) is one of the most-used clinical scoring systems for assessing the severity of asthma exacerbations in children. The aim of the present study was to validate a Spanish version of the PASS in a population of Hispanic children with asthma exacerbations living in urban Bogota, Colombia.

METHODS

In a prospective cohort and a validation study, parents/caregivers of children between 2 and 18 years old attended in the emergency department (ED) with asthma exacerbations who were admitted to the inpatient unit were invited to participate in the study. During the hospitalization period, we gathered the necessary data for assessing the criterion validity (comparing its score with the Pediatric Respiratory Assessment Measure [PRAM]), construct validity, interrater reliability, responsiveness, and internal consistency of the Col-PASS, the Colombian version of the PASS.

RESULTS

At baseline, the scores of the Col-PASS correlated positively with the scores of the PRAM score (ρ = 0.588, p < .001). The baseline Col-PASS scores in patients who required admission to a more complex service were significantly higher than those in patients who presented clinical improvement (1.0 (0.0-2.0) vs. 0.0 (0.0-0.0), p < .001). The interrater reliability was found to be κ = 0.897, 95% CI 0.699-1.000, p < .001. Cronbach's α was .701 for the questionnaire as a whole.

CONCLUSION

The Col-PASS has excellent construct validity, adequate criterion validity, interrater reliability, responsiveness; and acceptable internal consistency when used in children between 2 and 18 years old with asthma exacerbations.

Efficacy of oral corticosteroids for acute preschool wheeze: a systematic review and individual participant data meta-analysis of randomised clinical trials

BACKGROUND

Oral corticosteroids are commonly used for acute preschool wheeze, although there is conflicting evidence of their benefit. We assessed the clinical efficacy of oral corticosteroids by means of a systematic review and individual participant data (IPD) meta-analysis.

METHODS

In this systematic review with IPD meta-analysis, we systematically searched eight databases (PubMed, Ovid Embase, CINAHLplus, CENTRAL, ClinicalTrials.gov, EudraCT, EU Clinical Trials Register, WHO Clinical Trials Registry) for randomised clinical trials published from Jan 1, 1994, to June 30, 2020, comparing oral corticosteroids with placebo in children aged 12 to 71 months with acute preschool wheeze in any setting based on the Population, Intervention, Comparison, Outcomes framework. We contacted principal investigators of eligible studies to obtain deidentified individual patient data. The primary outcome was change in wheezing severity score (WSS). A key secondary outcome length of hospital stay. We also calculated a pooled estimate of six commonly reported adverse events in the follow-up period of IPD datasets. One-stage and two-stage meta-analyses employing a random-effects model were used. This study is registered with PROSPERO, CRD42020193958.

FINDINGS

We identified 16 102 studies published between Jan 1, 1994, and June 30, 2020, from which there were 12 eligible trials after deduplication and screening. We obtained individual data from seven trials comprising 2172 children, with 1728 children in the eligible IPD age range; 853 (49·4%) received oral corticosteroids (544 [63·8%] male and 309 [36·2%] female) and 875 (50·6%) received placebo (583 [66·6%] male and 292 [33·4%] female). Compared with placebo, a greater change in WSS at 4 h was seen in the oral corticosteroids group (mean difference -0·31 [95% CI -0·38 to -0·24]; p=0·011) but not 12 h (-0·02 [-0·17 to 0·14]; p=0·68), with low heterogeneity between studies (I2=0%; τ2<0·001). Length of hospital stay was significantly reduced in the oral corticosteroids group (-3·18 h [-4·43 to -1·93]; p=0·0021; I2=0%; τ2<0·001). Subgroup analyses showed that this reduction was greatest in those with a history of wheezing or asthma (-4·54 h [-5·57 to -3·52]; pinteraction=0·0007). Adverse events were infrequently reported (four of seven datasets), but oral corticosteroids were associated with an increased risk of vomiting (odds ratio 2·27 [95% CI 0·87 to 5·88]; τ2<0·001). Most datasets (six of seven) had a low risk of bias.

INTERPRETATION

Oral corticosteroids reduce WSS at 4 h and length of hospital stay in children with acute preschool wheeze. In those with a history of previous wheeze or asthma, oral corticosteroids provide a potentially clinically relevant effect on length of hospital stay.

FUNDING

Asthma UK Centre for Applied Research.

Paediatrics: how to manage acute asthma exacerbations

Background

Asthma is the most common chronic disease of childhood and a major source of childhood health burden worldwide. These burdens are particularly marked when children experience characteristic ‘symptom flare-ups’ or acute asthma exacerbations (AAEs). AAE are associated with significant health and economic impacts, including acute Emergency Department visits, occasional hospitalizations, and rarely, death. To treat children with AAE, several medications have been studied and used.

Methods

We conducted a narrative review of the literature with the primary objective of understanding the evidence of their efficacy. We present this efficacy evidence in the context of a general stepwise management pathway for paediatric AAEs. This framework is developed from the combined recommendations of eight established (inter)national paediatric guidelines.

Discussion

Management of paediatric AAE centres around four major care goals: (1) immediate and objective assessment of AAE severity; (2) prompt and effective medical interventions to decrease respiratory distress and improve oxygenation; (3) appropriate disposition of patient; and (4) safe discharge plans. Several medications are currently recommended with varying efficacies, including heliox, systemic corticosteroids, first-line bronchodilators (salbutamol/albuterol), adjunctive bronchodilators (ipratropium bromide, magnesium sulfate) and second-line bronchodilators (aminophylline, i.v. salbutamol, i.v. terbutaline, epinephrine, ketamine). Care of children with AAE is further enhanced using clinical severity scoring, pathway-driven care and after-event discharge planning.

Conclusions

AAEs in children are primarily managed by medications supported by a growing body of literature. Continued efforts to study the efficacy of second-line bronchodilators, integrate AAE management with long-term asthma control and provide fair/equitable care are required.

Predicting Severe Asthma Exacerbations in Children: Blueprint for Today and Tomorrow

Severe asthma exacerbations are the primary cause of morbidity and mortality in children with asthma. Accurate prediction of children at risk for severe exacerbations, defined as those requiring systemic corticosteroids, emergency department visit, and/or hospitalization, would considerably reduce health care utilization and improve symptoms and quality of life. Substantial progress has been made in identifying high-risk exacerbation-prone children. Known risk factors for exacerbations include demographic characteristics (ie, low income, minority race/ethnicity), poor asthma control, environmental exposures (ie, aeroallergen exposure/sensitization, concomitant viral infection), inflammatory biomarkers, genetic polymorphisms, and markers from other "omic" technologies. The strongest risk factor for a future severe exacerbation remains having had one in the previous year. Combining risk factors into composite scores and use of advanced predictive analytic techniques such as machine learning are recent methods used to achieve stronger prediction of severe exacerbations. However, these methods are limited in prediction efficiency and are currently unable to predict children at risk for impending (within days) severe exacerbations. Thus, we provide a commentary on strategies that have potential to allow for accurate and reliable prediction of children at risk for impending exacerbations. These approaches include implementation of passive, real-time monitoring of impending exacerbation predictors, use of population health strategies, prediction of severe exacerbation responders versus nonresponders to conventional exacerbation management, and considerations for preschool-age children who can be especially high risk. Rigorous prediction and prevention of severe asthma exacerbations is needed to advance asthma management and improve the associated morbidity and mortality.

Impact of prehospital pediatric asthma management protocol adherence on clinical outcomes

OBJECTIVE

To evaluate the frequency of EMS protocol non-adherence during pediatric asthma encounters and its association with emergency department (ED) length of stay (LOS) and hospital admission.

METHODS

This is a retrospective review of asthma encounters aged 2-17 years transported by EMS to a pediatric ED from 2012 to 2017. Our primary outcome was hospital admission based on prehospital protocol adherence defined as: (1) bronchodilator administration, (2) treatment of hypoxia with oxygen, or (3) administration of intramuscular (IM) epinephrine in encounters with high severity of distress. Multivariable logistic regression estimated the association between protocol non-adherence and hospital admission.

RESULTS

During the study period, 290 EMS encounters met inclusion criteria. Median age was 9 years (IQR 5-12), 63% were male, 40% had moderate to severe exacerbations, and 24% were admitted. Protocol non-adherence occurred in 32% of encounters with failure to administer bronchodilators in 27% and failure to administer IM epinephrine when indicated in 83%. Prehospital steroids were administered in 8% of encounters. After adjusting for covariates, protocol non-adherence was not statistically associated with likelihood of inpatient admission (OR 1.3; 95% CI: 0.6-2.6).

CONCLUSIONS

Among prehospital pediatric asthma encounters, EMS protocol non-adherence is common but not associated with a higher frequency of hospital admission. Hospital admission was associated with acute exacerbation severity suggesting further research is needed to develop a valid prehospital asthma severity assessment scoring tool.

Supplemental data for this article can be accessed at publisher's website.

The clinical respiratory score predicts paediatric critical care disposition in children with respiratory distress presenting to the emergency department

Background

Respiratory distress is a common presenting complaint in children brought to the Emergency Department (ED). The Clinical Respiratory Score (CRS) has shown promise as a screen for severe illness in High Income Countries. We aimed to validate the admission CRS in children presenting to the ED of a Low-to Middle Income Country.

Methods

Children (1 month to 16 years) presenting with respiratory distress to the ED of the Aga Khan University Hospital, Karachi, Pakistan, between November 2015 to March 2016, were enrolled. The CRS was measured at initial presentation, prior to any management and 2 h after treatment was started. The predictive value for admission to the paediatric critical care units for a variety of cut offs for CRS at presentation were derived.

Results

A total of 112 children (70% male) of median age 12 months (IQR 2, 34.5 months) were enrolled. Patients with severe CRS (score 8–12) at presentation were more likely to be admitted to paediatric critical care (90% vs. 23% with mild-moderate CRS; OR: 5.7; 95% CI: 2.2–15.3, p < 0.001). The sensitivity and specificity of CRS > 3 in predicting outcome were 94% (95% CI 79.8–99.3) and 40% (95% CI 35–45), respectively, with a positive likelihood ratio of 1.6 (95% CI 1.31–1.98) and negative predictive value of 94% (95% CI 81–98).

Conclusion

An admission CRS of > 3 in the ED of a Low-to Middle Income Country had excellent predictive value for disease severity, and it should be considered for incorporation into ED triage protocols.

Adapting an Evidence-Based Pediatric Acute Asthma Exacerbation Severity Assessment Tool for Pediatric Primary Care

INTRODUCTION

The purposes of this project were (a) to examine criteria derived from evidence-based pediatric acute asthma exacerbation assessment tools, asthma scores, and the acute asthma prediction rule validated and used in the emergency department and (b) to adapt these criteria for pediatric primary care.

METHOD

The three stages of the project included (a) identification of criteria in a literature review, (b) validation of the criteria by an expert panel, and (c) adaptation of the criteria in the design of an assessment tool.

RESULTS

The criteria were validated and adapted in the design of The Pediatric Acute Asthma Exacerbation Severity Assessment and Disposition Decision-Making Tool for Pediatric Primary Care.

DISCUSSION

The adaptation of criteria derived from the evidence and validated by an expert panel will inform and guide clinicians in assessing severity and support decision making in determining disposition of pediatric patients presenting with an acute asthma exacerbation in primary care.

Pediatric acute asthma exacerbations: Evaluation and management from emergency department to intensive care unit

OBJECTIVE

The goal of this report is to review available modalities for assessing and managing acute asthma exacerbations in pediatric patients, including some that are not included in current expert panel guidelines. While it is not our purpose to provide a comprehensive review of the National Asthma Education and Prevention Program (NAEPP) guidelines, we review NAEPP-recommended treatments to provide the full range of treatments available for managing exacerbations with an emphasis on the continuum of care between the ER and ICU.

DATA SOURCES

We searched PubMed using the following search terms in different combinations: asthma, children, pediatric, exacerbation, epidemiology, pathophysiology, guidelines, treatment, management, oxygen, albuterol, β2-agonist, anticholinergic, theophylline, corticosteroid, magnesium, heliox, BiPAP, ventilation, mechanical ventilation, non-invasive mechanical ventilation and respiratory failure. We attempted to weigh the evidence using the hierarchy in which meta-analyses of randomized controlled trials (RCTs) provide the strongest evidence, followed by individual RCTs, followed by observational studies. We also reviewed the NAEPP and Global Initiative for Asthma expert panel guidelines.

RESULTS AND CONCLUSIONS

Asthma is the most common chronic disease of childhood, and acute exacerbations are a significant burden to patients and to public health. Optimal assessment and management of exacerbations, including appropriate escalation of interventions, are essential to minimize morbidity and prevent mortality. While inhaled albuterol and systemic corticosteroids are the mainstay of exacerbation management, escalation may include interventions discussed in this review.

Utility of portable spirometry in a pediatric emergency department in children with acute exacerbation of asthma

OBJECTIVES

The primary purpose of this study was to determine if portable spirometers can be successfully used in an emergency department (ED) in children with an acute exacerbation of asthma. The secondary purpose of this study was to determine if a validated clinical asthma score (CAS) correlates with the spirometry results in children with an acute exacerbation of asthma.

METHODS

Children between the ages of 6 and 17 years who presented to an urban free-standing children's hospital ED with an acute exacerbation of asthma were enrolled in our study. On arrival, the CAS was recorded and then portable spirometry was performed. Attempts were continued until acceptable and reproducible flow loop measurements were obtained or until the patient was unable to perform further attempts. Outcomes included success at spirometry and correlation of spirometry with the CAS.

RESULTS

A total of 101 patients were enrolled in this study. Of those patients, only 35 (35%) were able to successfully perform portable spirometry. Successful spirometry attempts were associated with older age (10.4 vs. 8.9, p = .01), lower respiratory rates (24.8 vs. 30.2, p = .001), lower heart rates (110 vs. 124, p = .004), and lower CASs (8.4 vs. 9.7, p = .001). Increasing asthma severity correlated with a decreased likelihood of successfully obtaining a useful forced expiratory volume in 1 second (FEV(1)) measurement (p = .013). Compared with cases of mild asthma, a patient with moderate asthma is 33% less likely to be able to perform spirometry, and a patient with severe asthma 93% less likely to perform spirometry. The CAS correlated poorly with the more objective measure of FEV(1)% predicted in those with mild asthma.

CONCLUSION

Many children are incapable of using portable spirometry for the evaluation of acute exacerbations of asthma in the ED. The clinical asthma scoring system demonstrated poor correlation with portable spirometry measurements in terms of severity classification.

Prospective evaluation of two clinical scores for acute asthma in children 18 months to 7 years of age

OBJECTIVES

The objective was to evaluate the discriminatory ability of two clinical asthma scores, the Preschool Respiratory Assessment Measure (PRAM) and the Pediatric Asthma Severity Score (PASS), during an asthma exacerbation.

METHODS

This was a prospective cohort study in an academic pediatric emergency department (ED; 60,000 visits/year) conducted from March 2006 to October 2007. All patients 18 months to 7 years of age who presented for an asthma exacerbation were eligible. The primary outcome was a length of stay (LOS) of >6 hours in the ED or admission to the hospital. Clinical findings and components of the PRAM and the PASS were assessed by a respiratory therapist (RT) at the start of the ED visit and after 90 minutes of treatment.

RESULTS

During the study period, 3,845 patients were seen in the ED for an asthma exacerbation. Of these, 291 were approached to participate, and eight refused. Moderate levels of discrimination were found between a LOS of >6 hours and/or admission and PRAM (area under the receiver-operating characteristic curve [AUC] = 0.69, 95% confidence interval [CI] = 0.59 to 0.79) and PASS (AUC = 0.70, 95% CI = 0.60 to 0.80) as calculated at the start of the ED visit. Significant similar correlations were seen between the physician's judgment of severity and PRAM (r = 0.54, 95% CI = 0.42 to 0.65) and PASS (r = 0.55, 95% CI = 0.43 to 0.65).

CONCLUSIONS

The PRAM and PASS clinical asthma scores appear to be measures of asthma severity in children with discriminative properties.

Portable spirometry during acute exacerbations of asthma in children

BACKGROUND

Spirometry is the gold standard for assessment of asthma and is objective and non-invasive. This is a pilot study to evaluate whether portable spirometry can be successfully performed by children in the pediatric emergency department for acute exacerbations of asthma.

METHODS

We enrolled children more than 6 years of age presenting to an urban pediatric emergency department with a history of asthma during an acute exacerbation. On arrival and after each bronchodilator treatment, vital signs and a clinical score were recorded. Portable spirometry was then performed. Attempts were continued until acceptable and reproducible measurements were obtained or until the patient was unable to perform further attempts. Outcomes included success at spirometry and correlation of spirometry with clinical signs.

RESULTS

Thirty-four subjects were enrolled with a median age of 12 years. Ninety-one percent of subjects completed at least one attempt at spirometry. Seventy-three percent of all spirometry attempts were reproducible. Portable spirometry demonstrated increased severity of the exacerbation in comparison to clinical signs and peak expiratory flow. Percent of predicted forced expiratory volume in 1 second, ratio of forced expiratory volume in 1 second to forced vital capacity, and peak expiratory flow are all poorly correlated with degree of wheezing, clinical score, respiratory rate, and oxygen saturation (r < 0.5).

CONCLUSION

Portable spirometry can be successfully performed by children with acute exacerbations of asthma in the emergency department and demonstrated greater degrees of airway obstruction than did clinical signs. Spirometry provides objective, non-invasive measurements of the severity of airway obstruction in the emergency department for children with acute exacerbations of asthma.

A tree-based decision model to support prediction of the severity of asthma exacerbations in children

This paper describes the development of a tree-based decision model to predict the severity of pediatric asthma exacerbations in the emergency department (ED) at 2 h following triage. The model was constructed from retrospective patient data abstracted from the ED charts. The original data was preprocessed to eliminate questionable patient records and to normalize values of age-dependent clinical attributes. The model uses attributes routinely collected in the ED and provides predictions even for incomplete observations. Its performance was verified on independent validating data (split-sample validation) where it demonstrated AUC (area under ROC curve) of 0.83, sensitivity of 84%, specificity of 71% and the Brier score of 0.18. The model is intended to supplement an asthma clinical practice guideline, however, it can be also used as a stand-alone decision tool.

Quantitative end-tidal carbon dioxide in acute exacerbations of asthma

OBJECTIVE

To examine quantitative end-tidal carbon dioxide (ETCO(2)) in children with acute exacerbations of asthma. We hypothesize that quantitative ETCO(2) will be lower in children during an acute exacerbation of asthma and will correlate with the severity of the exacerbation. We also hypothesize that ETCO(2) can be successfully performed in all groups in the setting of a pediatric emergency department.

STUDY DESIGN

Patients with acute exacerbation of asthma (n = 86) and control subjects without respiratory or metabolic disturbances (n = 88) were prospectively enrolled in a pediatric emergency department. A physical examination, vital signs, and ETCO(2) measurements were performed on arrival and, in the patients with asthma, after each bronchodilator treatment.

RESULTS

ETCO(2) was measured successfully in 97% of enrolled children. After adjusting for respiratory rate, ETCO(2) was significantly lower in patients with acute exacerbation of asthma than in control subjects (P < .001). ETCO(2) measured after the first and after the final bronchodilator treatment were significantly associated with the number of bronchodilator treatments received and with hospital admission (P < or = .002).

CONCLUSIONS

ETCO(2) can be successfully measured in all children and is significantly lower in children with acute exacerbations of asthma compared with healthy control subjects. Quantitative ETCO(2) may be an objective, noninvasive, and effort-independent way to assess the severity of asthma.

The Pediatric Respiratory Assessment Measure: a valid clinical score for assessing acute asthma severity from toddlers to teenagers

OBJECTIVE

To determine the performance characteristics of the Preschool Respiratory Assessment Measure (PRAM) in preschool and school-aged children with acute asthma.

STUDY DESIGN

In a prospective cohort study, we examined the validity, responsiveness, and reliability of the PRAM in children aged 2 to 17 years with acute asthma. The study involved more than 100 nurses and physicians who recorded the PRAM on triage, after initial bronchodilation, and at disposition. Predictive validity and responsiveness were examined using disposition as outcome.

RESULTS

The PRAM was recorded in 81% (n = 782) of patients at triage. The PRAM at triage and after initial bronchodilation showed a strong association with admission (r = 0.4 and 0.5, respectively; P < .0001), thus supporting its ability to distinguish across severity levels. The responsiveness coefficient of 0.7 indicated good ability to identify change after bronchodilation. The PRAM showed good internal consistency (Cronbach alpha = 0.71) and inter-rater reliability (r = 0.78) for all patients and across all age groups.

CONCLUSIONS

Good performance characteristics were observed in all age groups, making the PRAM an attractive score for assessing asthma severity and response to treatment.

Effect of a clinical pathway on the hospitalisation rates of children with asthma: a prospective study

AIM

To determine the effect of implementing a clinical pathway, using evidence-based clinical practice guidelines, for the emergency care of children and adolescents with asthma.

METHODS

A prospective, before-after, controlled trial was conducted, which included patients aged 1-18 years who had acute exacerbations of asthma treated in a tertiary care paediatric emergency department. Data were collected for identical 2-month seasonal periods before and after implementation of the clinical pathway to determine hospitalisation rate and other outcomes. For 2 weeks after emergency visits, the rate at which patients returned to emergency care for worsening asthma was evaluated. A multidisciplinary panel, using national guidelines and a systematic review, developed the pathway.

RESULTS

267 patients were studied. The rate of hospitalisation was significantly lower in the post-implementation group (10/74; 13.5%) than in the pre-implementation control group (53/193; 27.5%; p = 0.02; number needed to treat 7.1). All reduction in hospitalisation occurred in children with moderate to severe asthma exacerbation. After implementation of the clinical pathway, the rate of administration of oral corticosteroids to patients with moderate or severe exacerbations increased from 71% to 92% (p = 0.01), and significantly more patients received beta2-agonists in the first hour (p = 0.02). No significant change in relapse to acute care occurred within 2 weeks (p = 0.19).

CONCLUSIONS

An evidence-based clinical pathway for children and adolescents with moderate to severe exacerbations of acute asthma markedly decreases their rate of hospitalisation without increased return to emergency care.

Effect of pregnancy and stage of pregnancy on asthma severity: a systematic review

Although pregnancy is purported to affect maternal asthma, the literature has not been reviewed systematically. The purpose of this systematic review was to determine, among pregnant women with asthma, whether pregnancy and stage of pregnancy influence maternal asthma severity. Six electronic databases were searched in January 2003 for prospective studies of currently asthmatic, pregnant women who were enrolled before the third trimester and assessed with objective measures of asthma severity or validated severity scales. Three studies reported 54 pregnant women with asthma who met the inclusion criteria. The most valid study indicated that bronchial hyperresponsiveness to methacholine improved between preconception and pregnancy in 69% of the women, although it deteriorated in 31% of the women. Further, this improvement peaked in the second trimester, reverted after delivery, and was greatest among those women who were most hyperresponsive initially. Lung function also showed a trend towards improvement during pregnancy that was not significant. Large, well-conducted population-based studies that explore different aspects of asthma severity are needed to substantiate these preliminary results.

Performance of a novel clinical score, the Pediatric Asthma Severity Score (PASS), in the evaluation of acute asthma

OBJECTIVES

To evaluate the reliability, validity, and responsiveness of a new clinical asthma score, the Pediatric Asthma Severity Score (PASS), in children aged 1 through 18 years in an acute clinical setting.

METHODS

This was a prospective cohort study of children treated for acute asthma at two urban pediatric emergency departments (EDs). A total of 852 patients were enrolled at one site and 369 at the second site. Clinical findings were assessed at the start of the ED visit, after one hour of treatment, and at the time of disposition. Peak expiratory flow rate (PEFR) (for patients aged 6 years and older) and pulse oximetry were also measured.

RESULTS

Composite scores including three, four, or five clinical findings were evaluated, and the three-item score (wheezing, prolonged expiration, and work of breathing) was selected as the PASS. Interobserver reliability for the PASS was good to excellent (kappa = 0.72 to 0.83). There was a significant correlation between PASS and PEFR (r = 0.27 to 0.37) and pulse oximetry (r = 0.29 to 0.41) at various time points. The PASS was able to discriminate between those patients who did and did not require hospitalization, with area under the receiver operating characteristic curve of 0.82. Finally, the PASS was shown to be responsive, with a 48% relative increase in score from start to end of treatment and an overall effect size of 0.62, indicating a moderate to large effect.

CONCLUSIONS

This clinical score, the PASS, based on three clinical findings, is a reliable and valid measure of asthma severity in children and shows both discriminative and responsive properties. The PASS may be a useful tool to assess acute asthma severity for clinical and research purposes.

Performance of a novel clinical score, the Pediatric Asthma Severity Score (PASS), in the evaluation of acute asthma

OBJECTIVES

To evaluate the reliability, validity, and responsiveness of a new clinical asthma score, the Pediatric Asthma Severity Score (PASS), in children aged 1 through 18 years in an acute clinical setting.

METHODS

This was a prospective cohort study of children treated for acute asthma at two urban pediatric emergency departments (EDs). A total of 852 patients were enrolled at one site and 369 at the second site. Clinical findings were assessed at the start of the ED visit, after one hour of treatment, and at the time of disposition. Peak expiratory flow rate (PEFR) (for patients aged 6 years and older) and pulse oximetry were also measured.

RESULTS

Composite scores including three, four, or five clinical findings were evaluated, and the three-item score (wheezing, prolonged expiration, and work of breathing) was selected as the PASS. Interobserver reliability for the PASS was good to excellent (kappa = 0.72 to 0.83). There was a significant correlation between PASS and PEFR (r = 0.27 to 0.37) and pulse oximetry (r = 0.29 to 0.41) at various time points. The PASS was able to discriminate between those patients who did and did not require hospitalization, with area under the receiver operating characteristic curve of 0.82. Finally, the PASS was shown to be responsive, with a 48% relative increase in score from start to end of treatment and an overall effect size of 0.62, indicating a moderate to large effect.

CONCLUSIONS

This clinical score, the PASS, based on three clinical findings, is a reliable and valid measure of asthma severity in children and shows both discriminative and responsive properties. The PASS may be a useful tool to assess acute asthma severity for clinical and research purposes.

Interrater agreement in the clinical evaluation of acute pediatric asthma

Prior studies of observer agreement of the clinical exam of children with asthma have focused on small numbers of specially trained observers, often in the setting of clinical trials. Our objective was to evaluate interobserver reliability in the physical exam of acute pediatric wheezing and asthma among a large group of diverse examiners, in a setting of routine clinical practice, and without prior special training. The setting was a large urban children's hospital. Observers were attending pediatric emergency physicians and fellows; hospital respiratory therapists; and emergency department (ED) nurses. Patients were children receiving nebulized medications for wheezing in the ED or inpatient asthma unit. Pairs of observers simultaneously but independently rated work of breathing, wheeze, decreased air entry, prolonged expiration, breathlessness, respiratory rate, mental status, and global (or overall) severity using a structured exam template. A total score for each exam was also evaluated. A total of 230 pairs of observations were performed; mean patient age was 5.3 years. For all pairs, the weighted kappa statistics for the exam components ranged from 0.61 to 0.74 (moderate or substantial agreement). The global severity category and total score had weighted kappas of 0.80 and 0.82, respectively (excellent agreement). Agreement was generally somewhat lower for unlike (different profession) observer pairs than for like observer pairs, but remained acceptable. Agreement in two age groups (< or = 3 years old and > or = 4) was at least moderate for all exam components analyzed. Spearman rank correlations between individual exam components and the global assessments of patient severity were all greater than 0.5, indicating at least moderate to good correlations. We found substantial interobserver agreement among a broad range of examiners in the components of the clinical examination of acute wheezing in both younger and older children. This is contrary to the commonly held observation that the poor interobserver reliability of physical exam findings in asthma may limit their usefulness as asthma outcome measures. Support for use of a structured respiratory exam format or template in asthma guidelines was also shown.