Association Between Corticosteroids and Outcomes in Children Hospitalized With Orbital Cellulitis

Essential Concepts for Reducing Bias in Observational Studies

Randomized controlled trials (RCTs) are the gold standard study design for clinical research, as prospective randomization, at least in theory, balances any differences that can exist between groups (including any differences not measured as part of the study) and isolates the studied treatment effect. Any remaining imbalances after randomization are attributable to chance. However, there are many barriers to conducting RCTs within pediatric populations, including lower disease prevalence, high costs, inadequate funding, and additional regulatory requirements. Researchers thus frequently use observational study designs to address many research questions. Observational studies, whether prospective or retrospective, do not involve randomization and thus have more potential for bias when compared with RCTs because of imbalances that can exist between comparison groups. If these imbalances are associated with both the exposure of interest and the outcome, then failure to account for these imbalances may result in a biased conclusion. Understanding and addressing differences in sociodemographic and/or clinical characteristics within observational studies are thus necessary to reduce bias. Within this Method/ology submission we describe techniques to minimize bias by controlling for important measurable covariates within observational studies and discuss the challenges and opportunities in addressing specific variables.

Variation in the Management of Hospitalized Children With Orbital Cellulitis Over 10 Years

OBJECTIVES

No previous study has examined the management of hospitalized children with orbital cellulitis at both children's and community hospitals across multiple sites in Canada. We describe variation and trends over time in diagnostic testing and imaging, adjunctive agents, empiric antibiotics, and surgical intervention in children hospitalized with orbital cellulitis.

PATIENTS AND METHODS

Multicenter cohort study of 1579 children aged 2 months to 18 years with orbital cellulitis infections admitted to 10 hospitals from 2009 to 2018. We assessed hospital-level variation in the use of diagnostic tests, imaging, antibiotics, adjunctive agents, surgical intervention, and clinical outcomes using X2, Mann-Whitney U, and Kruskal-Wallis tests. The association between clinical management and length of stay was evaluated with median regression analysis with hospital as a fixed effect.

RESULTS

There were significant differences between children's hospitals in usage of C-reactive protein tests (P < .001), computed tomography scans (P = .004), MRI scans (P = .003), intranasal decongestants (P < .001), intranasal corticosteroids (P < .001), intranasal saline spray (P < .001), and systemic corticosteroids (P < .001). Children's hospital patients had significantly longer length of hospital stay compared with community hospitals (P = .001). After adjustment, diagnostic testing, imaging, and subspecialty consults were associated with longer median length of hospital stay at children's hospitals. From 2009 to 2018, C-reactive protein test usage increased from 28.8% to 73.5% (P < .001), whereas erythrocyte sedimentation rate decreased from 31.5% to 14.1% (P < .001).

CONCLUSIONS

There was significant variation in diagnostic test usage and treatments, and increases in test usage and medical intervention rates over time despite minimal changes in surgical interventions and length of stay.

Factors Associated with Surgery and Imaging Characteristics in Severe Orbital Infections

OBJECTIVES

To evaluate risk factors associated with surgical intervention and subperiosteal/orbital abscess in hospitalized children with severe orbital infections.

STUDY DESIGN

We conducted a multicenter cohort study of children 2 months to 18 years hospitalized with periorbital or orbital cellulitis from 2009 to 2018 at 10 hospitals in Canada. Clinical details were extracted, and patients were categorized as undergoing surgical or medical-only management. Primary outcome was surgical intervention and the main secondary outcome was clinically important imaging. Logistic regression was used to identify predictors.

RESULTS

Of 1579 patients entered, median age was 5.4 years, 409 (25.9%) had an orbital/subperiosteal abscess, and 189 (12.0%) underwent surgery. In the adjusted analysis, the risk of surgical intervention was associated with older age (age 9 to <14: aOR 3.9, 95% CI 2.3-6.6; and age 14 to ≤18 years: aOR 7.0, 95% CI 3.4-14.1), elevated C-reactive protein >120 mg/L (aOR 2.8, 95% CI 1.3-5.9), elevated white blood cell count of 12-20 000/μL (aOR 1.7, 95% CI 1.1-2.6), proptosis (aOR 2.6, 95% CI 1.7-4.0), and subperiosteal/orbital abscess (aOR 5.3, 95% CI 3.6-7.9). There was no association with antibiotic use before hospital admission, sex, presence of a chronic disease, temperature greater than 38.0°C, and eye swollen shut. Complications were identified in 4.7% of patients, including vision loss (0.6%), intracranial extension (1.6%), and meningitis (0.8%).

CONCLUSIONS

In children hospitalized with severe orbital infections, older age, elevated C-reactive protein, elevated white blood cell count, proptosis, and subperiosteal/orbital abscess were predictors of surgical intervention.