A nationwide survey of the management of unintentional-low dose tricyclic antidepressant ingestions involving asymptomatic children: implications for the development of an evidence-based clinical guideline.

BACKGROUND

The triage of unintentional tricyclic and cyclic antidepressant ingestions involving children <6 years seems based on single cases or small studies. Walsh, in describing 2 cases involving 15-20 mg/kg ingestions, recommended hospitalizing all children ingesting tricyclic and cyclic antidepressants.

OBJECTIVE

To evaluate the patterns of triage for pediatric tricyclic and cyclic antidepressants practiced by regional poison control centers nationwide, and to determine the amount ingested (mg/kg) that resulted in referral to the emergency department, including the recommended duration of observation time for asymptomatic children. Second, to analyze the cost implications, as well as the need for a practice guideline based on severity stratification.

METHODS

We sent a survey to 44 major regional poison control centers. We reviewed Health Care Financing Administration's tricyclic and cyclic antidepressants management related costs.

RESULTS

Thirty centers responded (68%). Eighty-seven percent of all centers send children, regardless of dose ingested, to the emergency department. Four out of the 30 recommended observation based on dose in mg/ kg ingested (range >1.5-5). Recommended observation times in the emergency department varied between 6-24 hours. Twenty-seven (90%) Poison Control Centers recommended 6 hours (although one recommended doing so only after administering activated charcoal). One recommended 6-12 hours of observation and 2 Poison Control Centers recommended 24-hour observation. Only 1 center recommended obtaining tricyclic and cyclic antidepressant plasma levels.

DISCUSSION

In our review of the literature, the lowest toxic dose reported was 6.7 mg/kg. This is consistent with our Poison Control Center data over the past 5 years where no child was toxic at doses <5 mg/kg. While only 13% of the centers surveyed utilize a stratification strategy to triage pediatric tricyclic and cyclic antidepressant ingestions, the current referral patterns support evaluation based on pharmacokinetics, not worst case incidents.

CONCLUSION

This survey demonstrates that most children with tricyclic and cyclic antidepressant ingestions will be sent to the emergency department, regardless of the amount ingested. A prospective study is needed to determine the probable dose of tricyclic and cyclic antidepressant ingestions that requires observation at a health care facility.