Ibrahim Migdady1,2, Moein Amin3, Aaron Shoskes3, Catherine Hassett3, Sung-Min Cho4, Pravin George5, Alexander Rae-Grant3. 1. Division of Neurocritical Care, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Lunder 650, Boston, MA, 02114, USA. imigdady@mgh.harvard.edu. 2. Department of Neurology, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA. imigdady@mgh.harvard.edu. 3. Department of Neurology, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA. 4. Departments of Neurology, Neurological Intensive Care, Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA. 5. Department of Neurointensive Care, Cerebrovascular Center, Cleveland Clinic, Cleveland, OH, USA.
Abstract
BACKGROUND: Persistent apnea despite an adequate rise in arterial pressure of CO2 is an essential component of the criteria for brain death (BD) determination. Current guidelines vary regarding the utility of arterial pH changes during the apnea test (AT). We aimed to study the effect of incorporating an arterial pH target < 7.30 during the AT (in addition to the existing PaCO2 threshold) on brain death declarations. METHODS: We performed retrospective analysis of consecutive adult patients who were diagnosed with BD and underwent AT at the Cleveland Clinic over the last 10 years. Data regarding baseline and post-AT blood gas analyses were collected and analyzed. RESULTS: Ninety-eight patients underwent AT in the study period, which was positive in 89 (91%) and inconclusive in 9 (9%) patients. The mean age was 50 years old (standard deviation [SD] 16) and 54 (55%) were female. The most common etiology BD was hypoxic ischemic brain injury (HIBI) due to cardiac arrest (42%). Compared to those with positive AT, patients with inconclusive AT had a higher post-AT pH (7.24 vs 7.17, p = 0.01), lower PaO2 (47 vs 145, p < 0.01), and a lower PaCO2 (55 vs 73, p = 0.01). Among patients with a positive AT using PaCO2 threshold alone, the frequency of patients with post-AT pH < 7.30 was 95% (83/87). CONCLUSION: Implementing a BD criteria requiring both arterial pH and PaCO2 thresholds reduced the total number of positive ATs; these inconclusive cases would have required longer duration of AT to reach both targets, repeated ATs, or ancillary studies to confirm BD. The impact of this on the overall number BD declarations requires further research.
BACKGROUND: Persistent apnea despite an adequate rise in arterial pressure of CO2 is an essential component of the criteria for brain death (BD) determination. Current guidelines vary regarding the utility of arterial pH changes during the apnea test (AT). We aimed to study the effect of incorporating an arterial pH target < 7.30 during the AT (in addition to the existing PaCO2 threshold) on brain death declarations. METHODS: We performed retrospective analysis of consecutive adult patients who were diagnosed with BD and underwent AT at the Cleveland Clinic over the last 10 years. Data regarding baseline and post-AT blood gas analyses were collected and analyzed. RESULTS: Ninety-eight patients underwent AT in the study period, which was positive in 89 (91%) and inconclusive in 9 (9%) patients. The mean age was 50 years old (standard deviation [SD] 16) and 54 (55%) were female. The most common etiology BD was hypoxic ischemic brain injury (HIBI) due to cardiac arrest (42%). Compared to those with positive AT, patients with inconclusive AT had a higher post-AT pH (7.24 vs 7.17, p = 0.01), lower PaO2 (47 vs 145, p < 0.01), and a lower PaCO2 (55 vs 73, p = 0.01). Among patients with a positive AT using PaCO2 threshold alone, the frequency of patients with post-AT pH < 7.30 was 95% (83/87). CONCLUSION: Implementing a BD criteria requiring both arterial pH and PaCO2 thresholds reduced the total number of positive ATs; these inconclusive cases would have required longer duration of AT to reach both targets, repeated ATs, or ancillary studies to confirm BD. The impact of this on the overall number BD declarations requires further research.
Authors: Ibrahim Migdady; Robert Scott Stephens; Carrie Price; Romergryko G Geocadin; Glenn Whitman; Sung-Min Cho Journal: J Thorac Cardiovasc Surg Date: 2020-03-21 Impact factor: 5.209
Authors: David M Greer; Sam D Shemie; Ariane Lewis; Sylvia Torrance; Panayiotis Varelas; Fernando D Goldenberg; James L Bernat; Michael Souter; Mehmet Akif Topcuoglu; Anne W Alexandrov; Marie Baldisseri; Thomas Bleck; Giuseppe Citerio; Rosanne Dawson; Arnold Hoppe; Stephen Jacobe; Alex Manara; Thomas A Nakagawa; Thaddeus Mason Pope; William Silvester; David Thomson; Hussain Al Rahma; Rafael Badenes; Andrew J Baker; Vladimir Cerny; Cherylee Chang; Tiffany R Chang; Elena Gnedovskaya; Moon-Ku Han; Stephen Honeybul; Edgar Jimenez; Yasuhiro Kuroda; Gang Liu; Uzzwal Kumar Mallick; Victoria Marquevich; Jorge Mejia-Mantilla; Michael Piradov; Sarah Quayyum; Gentle Sunder Shrestha; Ying-Ying Su; Shelly D Timmons; Jeanne Teitelbaum; Walter Videtta; Kapil Zirpe; Gene Sung Journal: JAMA Date: 2020-09-15 Impact factor: 56.272