Hospital type, region significant predictors for observation time following anaphylaxis

Key takeaways:

• Less than 2% of participants said their ED had specific observation guidelines.
• Rural hospitals had shorter observation times than urban or urban cluster hospitals.

Most EDs do not have specific guidelines for observation time following anaphylaxis, and the average duration depends largely on comorbidities and the type of hospital, according to a survey study.

“Although experts have varying recommendations, such as general observation times of up to 6 to 8 hours and considering discharging patients after 1 hour of observation if there are no severe symptoms and no repeat doses of epinephrine, there are no evidence-based guidelines for appropriate observation times,” Timothy Nguyen, DO, internal medicine resident at the University of Kansas Medical Center and the University of Kansas School of Medicine – Wichita, and colleagues wrote. “Our survey study aimed to better understand anaphylaxis observation decisions from the perspective of emergency physicians.”

The researchers surveyed 892 emergency physicians in Kansas through the REDCap survey platform. The survey asked participants about observation times based on a variety of factors such as patient age and symptoms, as well as physician demographics such as age, sex, practice length, hospital type and region.

Fewer than 2% of respondents said their ED had specific observation guidelines.

The average observation time for patients without comorbidities was 2.94 hours (standard error [SE] = 0.11). Most comorbidities extended the average observation time, including airway involvement (+2.02; SE = 0.119 hours), hypotension (+2.13 hours; SE = 0.115), COPD or asthma history (+0.735 hours; SE = 0.091) and previous anaphylaxis (+0.808 hours; SE = 0.0997). Patients who only experienced cutaneous symptoms were discharged an average of 0.81 hours (SE = 0.116) sooner.

Patient age also influenced observation times; patients aged younger than 18 years averaged an extra 0.278 hours (SE = 0.076), and patients aged 65 years and older averaged an extra 0.768 hours (SE = 0.0868).

Practice length, hospital type and region had the most notable differences in observation times.

Physicians who had been in practice longer tended to have longer observation times, with an average of 2.25 hours among residents, 2.8 hours in the first 3 years of practice, 3 hours among those practicing for 3 to 9 years and 2.9 hours among physicians who have been practicing for 10 or more years.

Quaternary care and academic hospitals had the longest average observation time (3.4 hours), followed by small community hospitals (3 hours), freestanding EDs (3 hours), tertiary care EDs (2.7 hours) and critical access hospitals (2.4 hours).

Hospitals in urban regions averaged longer observation times (3 hours) than urban cluster regions (2.7 hours) and rural regions (2.3 hours).

The researchers noted that provider age was a significant predictor, with physicians aged 45 to 54 years having the shortest observation times (–1.27 hours; P < .001). Average observation times were the same among male and female physicians.

“Notably, the emergency physicians’ perception of anaphylaxis observation, at an average time of 2.9 hours, is significantly shorter than the recommended 6 to 8 hours after epinephrine administration,” Nguyen and colleagues wrote. “Regarding physician characteristics, age, hospital type and location were significant factors. The approach of emergency physicians in critical access EDs and rural settings to observation times tended to be significantly shorter than those in EDs in other settings. Higher demand and resource constraints in rural areas likely contribute to this perspective.”