The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts


Brady Scott1, Michael A. Gentile1, Janice J. Thalman1, Neil R. MacIntyre1

Background: An important component of determining brain death is evaluation of drive to breathe. Apnea Brain Death Assessments (ABDA) are used to aid in determining brain death by elevating carbon dioxide levels and evaluating the presence or absence of spontaneous breathing. While this method of brain death determination is often utilized it is not without potential complications. The possibility of indeterminate testing and inaccuracies also exist. Because practice guidelines regarding apnea brain death assessment have not yet been established, we conducted a survey to evaluate practice variability.

Methods: A ten question anonymous survey was sent out via the AARC Acute Care Section's e-mail list. Section members who subscribe to the e-mail list were asked to complete the survey online. A total of 29 surveys were completed.

Results: Demographics: 68% percent of responders were from an academic institution, 32% private institution. 52% were from facilities with 501+ patient care beds, 41% have 201-500 patient care beds, and 7% reported 200 or less beds. 45% of respondents reported doing 20 or more apnea brain death assessments each year.

Selected responses:

100% reported that a respiratory therapist must be present during the ABDA.
90% reported that arterial blood gas analysis is used to help determine the adequacy of the hypercapneic stimulus.
85% report that patients are observed for absence of respiratory effort for 5 or more minutes.
3%, or 1 respondent utilize specialty gas mixtures ie, 10% CO2/90% O2 to increase the patient's carbon dioxide level more rapidly.
38% used end-tidal or transcutaneous carbon dioxide monitoring during ABDA.
58% would repeat the study if the PaCO2 level was below that of the specified level on their policy/procedure but no signs of spontaneous breathing was noted. 46% would rule the study indeterminate, and 8% would consider the study negative indicating a presence of brain stem function. (multiple answers were allowed)
18% of those who reported indicated that if the study was positive (indicating an absence of brainstem function) they were required to repeat the study.

Conclusion: Clearly, wide practice variability exists between institutions regarding ABDA. Specific guidelines regarding this study may help enable clinicians to become more confident in making brain death determinations. More in depth evaluation of the wide practice variation is needed.