To the Editor:
Methylxanthines, including aminophylline and theophylline, have long played a significant role in the treatment of pediatric acute asthma exacerbations.1 Current expert guidelines recommend against aminophylline use for acute exacerbations because of the availability of selective β2-agonists such as albuterol, in addition to the narrow therapeutic index and the limited evidence for efficacy of this drug.1-3 We sought to examine whether aminophylline continues to be used for status asthmaticus in pediatric ICUs (PICUs) by surveying PICU fellowship training programs.
We administered an e-mail-based questionnaire to 58 pediatric critical care fellowship directors in the United States representing a geographic sampling of small to large training programs. The survey consisted of 15 questions pertaining to the use of aminophylline for status asthmaticus in the PICU (e-Appendix 1). The survey was distributed three times at 3-week intervals, and responses were anonymous. The study protocol and questionnaire were approved by the Vanderbilt University institutional review board (protocol No. 101136).
Responses were received from 39 of the surveyed program directors (67%). Twenty-three of those responses (59%) indicated that their PICUs currently use aminophylline for status asthmaticus. All positive respondents (100%) indicated that aminophylline use was based on clinical judgment rather than institutional protocol. Twenty of those using aminophylline (87%) stated that the medication was used only when other treatments had failed. Fourteen of the respondents (61%) whose institution used aminophylline identified a therapeutic range for serum aminophylline levels. Six of these respondents (43%) identified a therapeutic serum level of 10 to 20 μg/mL for aminophylline, the generally accepted therapeutic range.4 There was variation in the reporting of both the minimal effective serum level (mean, 10 μg/mL; range, 5-15 μg/mL) and the toxic serum level (mean, 17.9 μg/mL; range, 10-25 μg/mL).
Aminophylline continues to be used to treat status asthmaticus in PICUs, as determined by surveying fellowship training programs, despite limited evidence for efficacy and expert guidelines recommending against its use for this purpose. If pediatric critical care physicians are to continue to use this drug, further studies are recommended and warranted to assess its efficacy and safety.
Acknowledgments
Role of sponsors: The sponsor had no role in the design of the study, the collection and analysis of the data, or in the preparation of the manuscript.
Additional information: The e-Appendix can be found in the Online Supplement at http://chestjournal.chestpubs.org/content/141/4/1122/suppl/DC1.
Footnotes
Funding/Support: This research was supported by the National Institutes of Health [Grant K23 HL80005-01A2 to Dr Arnold].
Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (http://www.chestpubs.org/site/misc/reprints.xhtml).
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