About

Joseph J. Zorc, MD, MSCE, is a Professor of Pediatrics (Emergency Medicine) at the Children's Hospital of Philadelphia. He serves as the Director of Emergency Information Systems at the same institution and holds the Mark Fishman Endowed Chair in Genomics and Computational Science. Dr. Zorc is also the Medical Director of Analytics at the Center for Healthcare Quality and Analytics at the Children's Hospital of Philadelphia. His academic and clinical work is focused on pediatric emergency medicine, with a particular emphasis on healthcare quality, analytics, and genomics.

Research topics

• Medicine
• Pediatrics
• Internal medicine
• Virology
• Surgery
• Emergency medicine

Selected publications

• Valved Holding Chambers for Acute Wheezing in Young Children

  JAMA Pediatrics · 2026-03-16

  articleSenior author
  PublisherDOI

• A randomised controlled trial comparing epinephrine and dexamethasone to placebo in the treatment of infants with bronchiolitis: the Bronchiolitis in Infants Placebo <i>versus</i> Epinephrine and Dexamethasone (BIPED) study protocol

  ERJ Open Research · 2025-03-20 · 2 citations

  articleOpen access

  Introduction Bronchiolitis exerts a significant burden of illness on infants worldwide. National guidelines advise only supportive care. There is evidence that treating infants with bronchiolitis with a combination of inhaled epinephrine and dexamethasone may reduce hospital admissions. Objective The aim of this study is to determine if infants with bronchiolitis treated with inhaled epinephrine (delivered by metered dose inhaler with spacer or nebuliser) in the emergency department and a 2-day course of oral dexamethasone have fewer hospitalisations compared to infants treated with placebo. Methods The BIPED study (Bronchiolitis in Infants Placebo versus Epinephrine and Dexamethasone) is a randomised, placebo-controlled, observer, investigator, clinician and patient blinded superiority clinical trial being conducted in 12 emergency departments across three countries (Canada, New Zealand and Australia). We will recruit 864 infants between 60 days and 12 months of age with bronchiolitis to receive either: 1) two inhaled epinephrine treatments (3 mg via nebuliser or 625 µg via metered dose inhaler with spacer) 30 min apart and a simultaneous dose of oral dexamethasone (0.6 mg·kg −1 , maximum 10 mg) in the emergency department with the dexamethasone repeated at 24 h; or 2) inhaled placebo and oral placebo. The primary outcome is hospital admission for bronchiolitis within 7 days (168 h) of enrolment. Secondary outcomes include hospital admission during enrolment and all-cause hospital admissions within 21 days of enrolment. Conclusion Given the burden of bronchiolitis, there is urgent need for a trial to confirm if combination therapy with epinephrine and dexamethasone is effective.

  PublisherDOI

• Thank You to PEC Reviewers!

  Pediatric Emergency Care · 2025-11-26

  articleSenior author
  PublisherDOI

• Analysis of the asthma scores recommended in guidelines for children presenting to the emergency department: a Pediatric Emergency Research Networks study

  Archives of Disease in Childhood · 2025-03-28 · 3 citations

  articleOpen access

  RATIONALE: While there are numerous published paediatric asthma scores, it is unknown how commonly scores are recommended in asthma guidelines across different geographical regions globally, and what their validation status is. OBJECTIVES: (1) To describe which clinical guidelines recommend asthma scores across different geographical regions. (2) To describe the initial and subsequent validation of the commonly recommended asthma scores. METHODS: Observational study of asthma scores recommended in guidelines for the management of acute paediatric asthma from institutions across the Pediatric Emergency Medicine Network; global paediatric emergency medicine research network comprising all eight local and regional paediatric emergency medicine research networks. MAIN RESULTS: 158 guidelines were identified. Overall, 83/158 (53%) guidelines recommend a bedside clinical score for assessment of asthma severity. While a single country-specific clinical score was recommended in all guidelines from Spain and Canada, 27/28 (96%) of the USA guidelines recommend a wide variety of scores, and scores are rarely recommended in guidelines from other research networks (PERUKI, Paediatric Emergency Research in the UK and Ireland and PREDICT, Paediatric Research in Emergency Departments International Collaborative in Australia and New Zealand) and other countries (Costa Rica, South Africa, Nigeria, Singapore, India).The Pediatric Respiratory Assessment Measure (PRAM) and the pulmonary score (PS) were the most frequently used scoring instruments. While the PRAM has undergone the most extensive validation, including construct validity, validation studies for the PS are limited. Inter-rater reliability, as well as the criterion, responsiveness and discriminative validity aspects represent the most common limitations in many of the scores. CONCLUSIONS: There are marked geographical differences in both the recommendation for and the type of clinical asthma score in clinical practice guidelines. While many asthma scores are recommended, most have insufficient validation.

  PublisherOA PDFDOI

• <scp>Intravenous Magnesium: Prompt use for Asthma in Children Treated in the Emergency Department</scp> (<scp>IMPACT</scp>‐<scp>ED</scp>), a pilot randomized trial

  Academic Emergency Medicine · 2025-03-17 · 4 citations

  articleOpen accessSenior author

  BACKGROUND: Asthma is the most common chronic illness of childhood and a leading cause of hospitalization and health care costs for children. Intravenous magnesium sulfate (IVMg) may help severely ill children avoid hospitalization when added to standard treatment in an emergency department (ED), but this has not been adequately evaluated in a large trial. We conducted a pilot trial to test procedures and gather information to plan a large multicenter trial. METHODS: Children 2-17 years old with severe acute asthma were randomized in a multicenter, double-blind, controlled trial of placebo (saline, 1 mL/kg, max 40 mL), low-dose IVMg (50 mg/kg, max 2 g), or high-dose IVMg (75 mg/kg, max 3 g) in addition to standard asthma therapy at the EDs of three tertiary pediatric hospitals between September 2022 and May 2023. We assessed the feasibility of delivering study drug within 90 min of treatment (defined as the start of the first inhaled albuterol) and monitoring for hypotension and obtained blood samples for pharmacologic analysis. Our target enrollment was one participant per site per week (90 total). RESULTS: A total of 52 patients were randomized, and 49 received study drug. Median (Q1, Q3) participant age was 6.3 (4.6, 9.6) years and 35 (67.3%) were male. Among 52 randomized participants, study drug was delivered within 90 min to 34 (65.4%), 486/542 (89.7%) anticipated blood pressure measurements were within time frames, 138/156 (88.5%) anticipated blood samples were obtained, and 38 (73.1%) were hospitalized. Hypotension was measured within 2 h of study drug administration in 2/18 (11.1%) who received placebo and 2/31 (6.5%) who received IVMg. CONCLUSIONS: Most anticipated blood pressure measurements and blood samples were obtained. Hypotension occurred at rates similar to previous reports. Lower-than-expected enrollment (related to low patient volumes) and timely delivery of study drug will require consideration for a larger trial.

  PublisherOA PDFDOI

• Azithromycin in Preschoolers with Severe Wheezing Episodes Diagnosed at the Emergency Department (AZ-SWED): A Randomized, Placebo-Controlled, Precision-Medicine Trial

  American Journal of Respiratory and Critical Care Medicine · 2025-05-01

  article

  Abstract Background and rationale. Over 2.2 million children aged 2-5 years have wheezing illnesses (WI) that are severe enough to require Emergency Department (ED) visits each year in the United States, and 15% of these children require hospitalization. There is new evidence suggesting an association between isolation of three pathogenic nasopharyngeal (NP) bacteria (3PB)(Neisseria catarrhalis, Hemophilus influenzae, Streptococcus pneumoniae)and preschool WI, but demonstration of a causal relation is lacking. Many patients with WI are treated with antibiotics, with scanty evidence supporting this approach. There is concern that excessive use of antibiotics promotes bacterial resistance. Two high profile, phase II clinical trials (PMID:26575060, PMID:26704020) performed in outpatient clinics recently showed significant reduction in WI symptoms when children were treated with Azithromycin (AZ) either before or soon after symptoms started, but whether AZ is effective in more severe cases requiring ED visits, is unknown. Another trial (PMID:28771627) analyzed 222 preschool children with wheeze in the ED and treated them with AZ or placebo, demonstrating no difference in duration of short-acting beta agonist use between groups. The study was discontinued prior to enrollment of the targeted sample size. No studies have assessed whether AZ could be differentially effective in WI with or without concomitant isolation of the 3PB. Study design. AZ-SWED is a parallel group, randomized(1:1), double-blind placebo-controlled trial testing the hypothesis that, in the ED setting, AZ can decrease symptoms of moderate to severe WI (i.e., those with a Pediatric Respiratory Assessment Measure [PRAM] score ≥4) during the five days following the ED visit, as assessed by the previously validated Asthma Flare-up Diary for Young Children (ADYC) instrument. The results were analyzed separately in the 3PB positive and in the 3PB negative groups, with power calculated assuming an effect on the ADYC score that was similar to that observed for fluticasone in a trial using the same ADYC instrument(PMID:26341275). A subgroup of participants was followed for an additional 3 weeks after the ED visit, providing additional NP swabs to assess clearance of the pathogenic bacteria and development of antibiotic resistance. Results. Recruitment started in September 2021, and on December 10, 2024, the NHLBI, under recommendation from the trial DSMB, stopped the AZ-SWED trial for futility. A total of 840 participants were randomized, of which 521 (62%) had an NP swab that was positive for at least one of the3PB. A total of 209 of those positive for one of the 3PB were followed for an additional 3 weeks. For the 3PBpositive group, the median (IQR) sum ADYC over 5 days was 9.59 (7.29,12.60) in the AZ arm and 9.72 (7.66,12.17) in the placebo arm (p=0.7). Similarly, in the 3PB negative group, the median (IQR) was 9.30 (6.97,11.62) in the AZ arm and 9.10 (7.19,11.45) in the placebo arm (p=0.7). Secondary outcomes of ED length of stay, hospital length of stay, and return visits within 72hours of the initial visit were similar between the two arms in both 3PBgroups. Analyses by sex and race showed no difference in effect of AZ across subgroups. Of 116 3PB positive subjects who returned for 1-week follow-up, 27/46(58.7%) in the AZ arm and 8/70 (11.4%) in the placebo arm were found to be negative for the 3PB after one week. Development of bacterial resistance was similar in the two arms. Significance of the study. Azithromycin did not decrease the severity of wheezing illnesses in 18 to &amp;lt;60-month-olds regardless of the presence or absence of H influenzae, M catarrhalis, or S pneumonia isolated from the participants’ nasopharynx at the time of the illness.

  PublisherDOI

• Liberalizing Maximum High-Flow Nasal Cannula Flow Rates in the General Inpatient Ward Is Associated With Decreased Intensive Care Admissions for Infants With Bronchiolitis

  Pediatric Emergency Care · 2025-04-07

  articleSenior authorCorresponding

  OBJECTIVE: To compare the use of intensive care for infants with bronchiolitis following a policy change increasing the rate maximums for high-flow oxygen given by nasal cannula [high-flow nasal cannula (HFNC)] allowable in the inpatient (IP) ward setting. METHODS: This was a retrospective pre-post cohort study at an urban, tertiary care children's hospital. Infants without complex chronic conditions presenting to the emergency department with bronchiolitis from December 2018 to March 2019 and December 2019 to March 2020 were included in the study. In December 2019, our institution increased the allowable HFNC flow rate on IP to 2 liters per minute/kilogram. The primary outcome was patient disposition from the emergency department. Secondary outcomes were the need for IP to pediatric intensive care unit (PICU) transfer, the need for care escalation to positive airway pressure or invasive mechanical ventilation, and hospital length of stay. RESULTS: In total, 1043 and 1104 patients were included in the 2018 to 2019 and 2019 to 2020 cohorts, respectively. Infants in the second cohort were more likely to be admitted, though this association was not significant after adjusting for patient age and triage acuity. Infants in the second cohort had a lower risk of admission to the PICU, before and after adjusting for age and triage acuity. The risk of IP-to-PICU transfer, risk of care escalation, and length of stay did not increase. CONCLUSIONS: Increasing HFNC flow rates up to 2 liters per minute/kilogram on IP wards was associated with a reduction in intensive care admission and appears safe by balancing measures of care escalation.

  PublisherDOI

• Audit and Feedback on Pediatric Emergency Department Performance Measures: A Stepped-Wedge Trial

  Hospital Pediatrics · 2025-10-09

  article

  BACKGROUND: Audit and feedback can prompt clinician improvements. The benefit of this approach in pediatric emergency department (PED) systems is unclear. We evaluated the feasibility of a multisite, monthly automated report card and its effect on quality performance within and across emergency department sites. METHODS: We conducted a stepped-wedge randomized trial across 4 academic and 3 affiliated PEDs in the Pediatric Emergency Care Applied Research Network between January 2013 and April 2016. The intervention consisted of monthly site-level quality performance reports featuring bar charts with benchmarks, visit counts, and 12-month trends derived from electronic health record (EHR) data. Measures included initial care documentation (weight, vital signs) and throughput (time to clinician, time to imaging results, left without being seen rate, and length of stay). We evaluated the intervention's effect on performance measures and slope changes at implementation. RESULTS: We included 1 426 109 encounters (864 940 during the preintervention period, 561 169 during the postintervention period). We observed improved performance for 4 measures: weight for all visits (+0.2%), documentation of all vitals (+10.1%), time to vitals documentation (-12.0%), and time to plain film radiology report (-3.5%). We observed a decline in performance measures related to throughput, with increases in time to clinician, mean length of stay, and the proportion of patients leaving without being seen. CONCLUSIONS: We demonstrate the feasibility of providing quality performance report cards to hospital leaders using EHR data. We found mixed results in terms of the effectiveness of improving site-level metrics. Future efforts may facilitate further refinement of these interventions prior to dissemination.

  PublisherDOI

• Home Use of Nonpharmacologic Interventions For Fracture Pain After Pediatric Emergency Department Discharge

  Journal of Emergency Medicine · 2025-08-20 · 1 citations

  article
  PublisherDOI

• Pharmacokinetics and Pharmacodynamics of Intravenous Magnesium Sulfate in Pediatric Acute Asthma Exacerbations

  The Journal of Clinical Pharmacology · 2025-01-07 · 3 citations

  articleOpen access

  Abstract Pediatric asthma exacerbations represent a significant cause of emergency department use and hospitalizations. Despite available treatment options, many children's exacerbations are refractory to standard therapies and require adjunct treatments. The Intravenous Magnesium: Prompt use for Asthma in Children Treated in the Emergency Department study investigated the pharmacology of intravenous magnesium sulfate (IVMg) in treating pediatric asthma exacerbations. Specifically, the objectives of the study included (1) externally validating a previously published population pharmacokinetic model and (2) linking serum magnesium concentrations with outcomes including asthma severity score (efficacy) and hypotension (safety). Data were obtained from 49 children prospectively treated with IVMg (placebo, 50 or 75 mg/kg) after presenting to the pediatric emergency department with an acute asthma exacerbation. Reductions in Pediatric Respiratory Assessment Measure scores were associated with both total and ionized serum magnesium area under the concentration–time curve (AUC 0–2 h ). Despite frequent study‐specific blood pressure monitoring, hypotension was uncommon in IVMg‐treated participants (n = 2/31), and no concentration dependence was observed. The findings signal that IVMg may be an efficacious and safe option for treating moderate–severe pediatric acute asthma exacerbations in the ED. Importantly, this study is the first to suggest a serum exposure target (total serum magnesium AUC 0‐2 h &gt;63.1 mg h/L) reflective of effective IVMg dosing in pediatric acute asthma. While further study in a larger clinical trial is needed to refine and validate this exposure target, these findings support the continued study of IVMg therapy as an adjunct therapeutic option in the setting of pediatric asthma exacerbations.

  PublisherOA PDFDOI

Recent grants

• NIH Grant K23HL074250

  NIH · $658k · 2008

Frequent coauthors

• Suzanne Schuh

  Institute for Clinical Evaluative Sciences

  239 shared

• Charles G. Macias

  238 shared

• Lalit Bajaj

  236 shared

• Amy C. Plint

  Agricultural Research Institute of Ontario

  234 shared

• David W. Johnson

  Alberta Children's Hospital Research Institute

  230 shared

• Stephen B. Freedman

  Alberta Children's Hospital

  227 shared

• Karen Black

  225 shared

• Kathy Boutis

  SickKids Foundation

  225 shared

Labs

• Joseph J. Zorc LabPI