Evaluation of Observation Periods and Biphasic Reaction Risk Factors in Pediatric Anaphylaxis Cases in the Pediatric Emergency Department: A Retrospective Study
Evaluation of Observation Periods and Biphasic Reaction Risk Factors in Pediatric Anaphylaxis Cases in the Pediatric Emergency Department: A Retrospective Study
This study reviews the medical records of children who presented to the pediatric emergency department of Adnan Menderes University Hospital with a diagnosis of anaphylaxis between January 2014 and December 2024. The aim is to determine how long children were observed in the emergency department, how often biphasic reactions (a second wave of symptoms) occurred, and which risk factors (such as delayed adrenaline use or asthma) may increase this risk. The results will help improve the care of children with anaphylaxis and guide recommendations for safe observation times.
Anaphylaxis is a severe, potentially life-threatening systemic hypersensitivity reaction with rapid onset. Its incidence in children has been rising worldwide. Although international recommendations emphasize the importance of post-reaction monitoring, the optimal observation period in pediatric patients remains uncertain, largely due to the risk of biphasic reactions, defined as recurrence of symptoms after initial resolution within 1-72 hours.
This retrospective observational study was conducted in the Pediatric Emergency Department of Adnan Menderes University Hospital. All patients younger than 18 years who presented with anaphylaxis between January 1, 2014, and December 31, 2024, were included. Diagnosis was based on the World Allergy Organization (WAO) 2020 criteria. Data were obtained from electronic medical records and emergency department charts.
Collected variables included demographics (age, sex), season of presentation, suspected triggers (food, drug, insect sting, exercise, idiopathic), clinical manifestations (cutaneous, respiratory, cardiovascular, gastrointestinal, neurological), comorbidities (such as asthma), acute treatments (epinephrine administration, time to first dose, number of doses, corticosteroids, antihistamines, fluid therapy), observation duration, need for hospital admission, and occurrence of biphasic reactions.
The primary objective is to determine the incidence and timing of biphasic reactions. Secondary objectives are to assess the average observation period in the emergency department, the frequency of hospital admission, and risk factors associated with biphasic reactions, including delayed epinephrine administration and history of asthma. Statistical analysis will include descriptive methods, group comparisons, and logistic regression to identify independent predictors of biphasic reactions.
This study is expected to contribute real-world data on pediatric anaphylaxis and inform clinical practice regarding safe observation times. Results will be compared with existing evidence and may support improvements in pediatric emergency protocols for anaphylaxis management.
Inclusion Criteria:
Age <18 years
Exclusion Criteria: