Background

Tachycardia is a very common abnormal vital sign in the Pediatric Emergency Department (ED). Tachycardia can have numerous underlying causes including less concerning clinical states such as fever, pain, and anxiety but can also be a sign of impending cardiovascular decompensation which occurs in shock, sepsis, and cardiac dysfunction.

Clinical Question

In patients less than 19 years of age, is tachycardia at the time of discharge from the ED or urgent care center associated with increased risk of revisit within 72 hours or the receipt of clinically important interventions, or hospital admission on revisit?

Population

Patients < 19 years who were treated and discharged from the EDs or urgent care centers at 2 freestanding Children’s hospitals (1 urban, 1 suburban), and 4 urgent care centers (1 urban, 3 suburban)

Intervention

Exposure: Tachycardia (> 99th percentile for age) at the time of discharge

Control

No Exposure: Normal heart rate for age at time at the time of discharge

Outcomes

Primary: An unscheduled revisit to the ED or urgent care within 72 hours.
Secondary: Receipt of clinically important interventions at time of revisit; association of pain, fever, and medications with discharge tachycardia; temporal relationship of the final documented pulse rate at discharge; and diagnosis associated with index visit (initial visit) and revisit. Clinically important interventions included respiratory support; medications such as saline, IVF, antibiotics, steroids, respiratory medication; procedures such as I&D or peripheral IV placement; admission

Design

Observational, retrospective, non-concurrent cohort study

Primary Results

Unscheduled revisits within 72 hours of discharge

  • 8.3% of patients (10,470/126,774) were tachycardic at time of discharge
  • 3.4% of patients (4,294/126,774) had an unscheduled revisit within 72 hours of discharge.
    • 4.8% of patients with discharge tachycardia (504/10,470) had a revisit within 72 hours of discharge.
    • 3.3% of patients without discharge tachycardia (3790/116,304) had a revisit within 72 hours.
  • Relative risk 1.45 (95% CI 1.2 -1.5) statistically significant
  • Risk difference: 1.5% (95% CI 1.1 – 2.0%) statistically significant
  • The risk of revisit was higher in those who were tachycardic at discharge

Secondary outcomes

  • Clinically important interventions on return visit
    • Tachycardic at discharge: 25.6%
    • Non-tachycardic at discharge: 24.6%
    • Risk difference: 1% (95% CI -2.8- 5.2%). Not statistically significant
  • Those who were tachycardic at discharge and had a revisit within 72 hours were more likely to require supplemental oxygen, respiratory medications and admission, antibiotics and admission, intravenous placement and admission, and were more likely to be tachycardic at their revisit.
  • There was no difference in the rate of admission on revisit between tachycardic and non-tachycardic patients with revisits. 

Strengths

  • Retrospective cohort chart review, well-designed study with little risk of bias
  • Large database with sample size of 126,774
  • Similar prognostic factors between groups; patient age, sex, race, ethnicity. Factors that are commonly associated with tachycardia such as pain scores, medications, and underlying primary diagnosis were also similar amongst groups
  • Large and diverse patient population that can be applied to most pediatric acute care settings

Limitations

  • Thresholds for heart rate are highly variable among practitioners
  • Revisits within 72 hours may have occurred at location outside of their study sites
  • Decisions to provide clinically important interventions are variable among physicians. There was no study protocol to guide management

Author's Conclusions

"Discharge tachycardia is associated with an increased risk of revisit. It is likely that tachycardia at discharge is not a critical factor associated with impending physiologic deterioration.”

Our Conclusions

Patients with tachycardia at the time of discharge that is not thought to be due to a serious underlying condition can be safely discharged with clear return precautions and scheduled follow up.

Potential Impact To Current Practice

This study’s results could lead to shorter emergency department visits, less testing, and provide the physician with a sense of reassurance that tachycardia, on its own at time of discharge, is not associated with a poor clinical outcome

Bottom Line

If serious causes of tachycardia have been addressed pediatric patients with isolated tachycardia at the time of discharge may be safely discharged.