Children with anaphylaxis who receive epinephrine less likely to need the ICU
Key takeaways:
- 44% of children with anaphylaxis received epinephrine before visiting the ED.
- There was no difference in admission to hospital wards.
- Children who used epinephrine were less likely to receive antihistamines.
Children with anaphylaxis who received epinephrine before going to the ED were significantly less likely to be admitted to the ICU, according to a study published in The Journal of Allergy and Clinical Immunology: In Practice.
These findings underscore the need for prompt administration of epinephrine when anaphylaxis develops, Roy Khalaf, fourth-year medical student, Faculty of Medicine and Health Sciences, McGill University, and colleagues wrote.
“This study was prompted by the observed inconsistency in the use of pre-hospital epinephrine for anaphylaxis and its unclear impact on hospital outcomes,” Khalaf told Healio.
The benefits of epinephrine in managing anaphylaxis are well-recognized, Khalaf continued, but there remains a knowledge gap regarding its independent role in reducing severe outcomes such as ICU admissions when accounting for confounders.
“By using propensity score matching, the study aimed to isolate the true effect of pre-hospital epinephrine on hospital outcomes, particularly ICU admissions, and address potential confounding variables,” he said.
Study design, results
The study included 3,158 children with anaphylaxis, defined as a reaction involving two or more organ systems and/or hypotension, who visited the Montreal Children’s Hospital ED between April 2011 and November 2023.
The cohort included 1,388 patients who received outpatient epinephrine (44%; 58.8% boys) and 1,770 patients who did not (56%; 58.8% boys).
Median ages included 7.3 years for those who received outpatient epinephrine and 5 years for those who did not (P = .01). Also, 79% of those who received outpatient epinephrine and 42.8% of those who did not had a known food allergy (P = .01).
Asthma rates included 18.6% among those who received outpatient epinephrine and 13.9% of those who did not (P = .01). Similarly, eczema rates included 17.1% of those who received outpatient epinephrine and 14.5% of those who did not (P = .04).
Rates of outpatient antihistamine use included 41.6% of those who received outpatient epinephrine and 45.8% of those who did not (P = .01). Rates of outpatient corticosteroid use included 2.2% of those who received outpatient epinephrine and 0.9% of those who did not (P = .01).
Using propensity score matching, which included age at reaction, male sex, known asthma, known food allergy, reaction at home, and reaction severity as covariates, rates of known food allergy included 79% among those who received outpatient epinephrine and 54.5% among those who did not (P = .01).
Propensity score matching also revealed that 2.2% of those with outpatient epinephrine use and 1.1% of those without it had used outpatient corticosteroids (P = .02).
Rates of ICU admission included 1.6% of those who did not receive outpatient epinephrine and 0.7% of those who did (P = .02).
“This is significant as it underscores the protective role of timely epinephrine administration in preventing severe outcomes,” Khalaf said.
However, the researchers said there was no significant difference in admission to hospital wards between the groups.
When the researchers examined the data from 1,388 patients who received outpatient antihistamines and 1,388 who did not, they said, there were no significant differences in hospital or ICU admissions even though they included the same covariates in the propensity score.
Conclusions, next steps
These findings underscore how prompt administration of epinephrine reduces ICU admissions among children with anaphylaxis, the researchers said, adding that caregivers and health care professionals alike need enhanced education and training to ensure its rapid use.
“These findings are significant because they confirm, using a robust statistical approach, that pre-hospital epinephrine improves critical outcomes even after accounting for confounding factors,” Khalaf said.
This study is contradictory to previous research, he continued, which found no significant difference in hospital admissions based on receipt of epinephrine before arriving at the hospital.
“Furthermore, it highlights that the timely administration of epinephrine may have a more pronounced impact on ICU admissions, providing compelling evidence to support its use,” Khalaf said.
Also, Khalaf said that physicians have a fundamental role in helping to increase the outpatient use of epinephrine by ensuring patients at risk for anaphylaxis have access to epinephrine autoinjectors and are properly instructed on their use.
“Additionally, during follow-up visits, it is important to educate patients on the importance of using epinephrine early and discuss barriers that might prevent its use, such as fear or misconceptions,” he said.
The use of epinephrine also can be encouraged through initiatives designed to raise awareness about anaphylaxis and epinephrine’s lifesaving role, Khalaf said.
Physicians also can advocate for laws to ensure broader access to affordable epinephrine autoinjectors and to incentivize health care providers to prescribe epinephrine and offer education to at-risk patients, he said.
For more information:
Roy Khalaf can be reached at roy.khalaf@mail.mcgill.ca.