Brain Death: Assessment, Controversy, and Confounding Factors

2013 ◽  
Vol 33 (6) ◽  
pp. 27-46 ◽  
Author(s):  
Richard B. Arbour
Keyword(s):  
Brain Death ◽  
Brain Stem ◽  
Vital Signs ◽  
Spinal Reflexes ◽  
High Dose ◽  
Loss Of Consciousness ◽  
Confounding Factors ◽  
Metabolic Suppression ◽  
Brain Stem Reflexes ◽  
The Brain

When brain injury is refractory to aggressive management and is considered nonsurvivable, with loss of consciousness and brain stem reflexes, a brain death protocol may be initiated to determine death according to neurological criteria. Clinical evaluation typically entails 2 consecutive formal neurological examinations to document total loss of consciousness and absence of brain stem reflexes and then apnea testing to evaluate carbon dioxide unresponsiveness within the brain stem. Confounding factors such as use of therapeutic hypothermia, high-dose metabolic suppression, and movements associated with complex spinal reflexes, fasciculations, or cardiogenic ventilator autotriggering may delay initiation or completion of brain death protocols. Neurodiagnostic studies such as 4-vessel cerebral angiography can rapidly document absence of blood flow to the brain and decrease intervals between onset of terminal brain stem herniation and formal declaration of death by neurological criteria. Intracranial pathophysiology leading to brain death must be considered along with clinical assessment, patterns of vital signs, and relevant diagnostic studies.

scholarly journals Guillain-Barré Syndrome Masquerading as Brain Death

2013 ◽  
Vol 1 (1) ◽  
pp. 53-55
Author(s):  
Fatema Ahmed ◽  
Mohammad Omar Faruq ◽  
ASM Areef Ahsan ◽  
Kaniz Fatema
Keyword(s):  
Brain Death ◽  
Brain Stem ◽  
Tactile Stimulation ◽  
External Noise ◽  
Spinal Reflexes ◽  
Case Review ◽  
Loss Of Function ◽  
Tongue Movement ◽  
Clinical Conditions ◽  
The Brain

Brain death is irreversible loss of function of the brain including the brain stem. Many clinical conditions may mimic brain death. This is a case review of a 27 year old Bangladeshi male who complaints heaviness of tongue and slurring of speech and was diagnosed as a case of bulbar palsy and found to develop ascending flaccid paralysis of limbs, subsequently he developed respiratory failure was placed on mechanical ventilator (MV) with GCS -3 and brain stem and all spinal reflexes were absent. The MRI & CSF studies were unremarkble. He was on MV and had no spontaneous breathing. A provisional diagnosis of GBS was made with a dfferential diagnosis of Brain stem death. Patient recieved 5 cycles of plasma pheresis without any clinical change. EEG showed cerebral reactivity on tactile stimulation and external noise stimulation. 31ist day of his illness patient developed involuntary tongue movement with pupils weakly reacting to light. 37th day of his illness he opened his eyes with vocal command. His neurological recovery continued till discharge DOI: http://dx.doi.org/10.3329/bccj.v1i1.14371 Bangladesh Crit Care J March 2013; 1: 53-55

Determination of Imminent Brain Death Using the Full Outline of Unresponsiveness Score and the Glasgow Coma Scale: A Prospective, Multicenter, Pilot Feasibility Study

2017 ◽  
Vol 35 (2) ◽  
pp. 203-207 ◽  
Author(s):  
Sergio Zappa ◽  
Nazzareno Fagoni ◽  
Michele Bertoni ◽  
Claudio Selleri ◽  
Monica Aida Venturini ◽  
...  
Keyword(s):  
Glasgow Coma Scale ◽  
Brain Death ◽  
Brain Stem ◽  
Deep Coma ◽  
Coma Scale ◽  
Four Score ◽  
Gcs Score ◽  
Brain Stem Reflexes ◽  
Pilot Feasibility Study

Purpose: To evaluate the accuracy of the imminent brain death (IBD) diagnosis in predicting brain death (BD) by daily assessment of the Full Outline of Unresponsiveness (FOUR) score and the Glasgow Coma Scale (GCS) with the assessment of brain stem reflexes. Materials and Methods: Prospective multicenter pilot study carried out in 5 adult Italian intensive care units (ICUs). Imminent brain death was established when the FOUR score was 0 (IBD-FOUR) or the GCS score was 3 and at least 3 among pupillary light, corneal, pharyngeal, carinal, oculovestibular, and trigeminal reflexes were absent (IBD-GCS). Results: A total of 219 neurologic evaluations were performed in 40 patients with deep coma at ICU admission (median GCS 3). Twenty-six had a diagnosis of IBD-FOUR, 27 of IBD-GCS, 14 were declared BD, and 9 were organ donors. The mean interval between IBD diagnosis and BD was 1.7 days (standard deviation [SD] 2.0 days) using IBD-FOUR and 2.0 days (SD 1.96 days) using IBD-GCS. Both FOUR and GCS had 100% sensitivity and low specificity (FOUR: 53.8%; GCS: 50.0%) in predicting BD. Conclusions: Daily IBD evaluation in the ICU is feasible using FOUR and GCS with the assessment of brain stem reflexes. Both scales had 100% sensitivity in predicting IBD, but FOUR may be preferable since it incorporates the pupillary, corneal, and cough reflexes and spontaneous breathing that are easily assessed in the ICU.

scholarly journals Brain stem death – an overview

2019 ◽  
Vol 87 (1) ◽  
pp. 18-20
Author(s):  
JSRG Saran ◽  
Jagadish R Padubidri
Keyword(s):  
Brain Death ◽  
Organ Donation ◽  
Brain Stem ◽  
Life Support ◽  
Brain Stem Death ◽  
Ethical Implications ◽  
Certification Procedure ◽  
Pass Through ◽  
The Uk ◽  
The Brain

The concept of brain death has been a very intriguing topic and has taken many forms over the years. Brain stem death is a complex state of inactivity defined by the loss of reflexes of the pathways that pass through the brain stem, the ‘shaft’ of the brain which links the spinal cord to the cerebral cortex and the cerebellum where there is apnoea, loss of eye movement and pain sensation. There are many criteria, based on which a person can be said to be brain dead. The best recognised of these are the Harvard, Minnesota and Philadelphia criteria. India follows the UK notion of brain stem death, and the Transplantation of Human Organs Act was passed in 1994 by the Indian parliament, which legalised brain-stem death, and in 1995 ordered the brain death certification procedure, which is certified by a ‘Board of Medical Experts’. Also, there are some legal and ethical implications that have to be considered in cases of disagreement in diagnosis among the panel of doctors, time of death in cases when patients’ relatives disagree or request more time for organ donation or to disconnect the life support system. In routine clinical practice, the issues pertaining to brain stem death should be dealt with by experienced physicians, counselling the family members or relatives and educating them about organ donation.

Jumping at Shadows

2019 ◽  
pp. 265-274
Author(s):  
Patrik N. Juslin
Keyword(s):  
Natural Selection ◽  
Brain Stem ◽  
Sound Intensity ◽  
Motor Behaviour ◽  
Acoustic Feature ◽  
Close Link ◽  
Psychological Mechanism ◽  
Brain Stem Reflexes ◽  
The Brain ◽  
Brain Stem Reflex

This chapter introduces a psychological mechanism that involves a close link between perception and motor behaviour. It focuses on a mechanism called the brain stem reflex, which refers to a process whereby an emotion is aroused in a listener because an acoustic feature — such as sound intensity or roughness of timbre — exceeds a certain cut-off value for which the auditory system has been designed by natural selection to quickly alert the brain. It is a kind of ‘override’ system, which is activated when an event seems to require first-priority attention. Brain stem reflexes are said to be ‘hard-wired’: they are quick, automatic, and unlearned.

Death, Brain Death, and the Limits of Science: Why the Whole-Brain Concept of Death is a Flawed Public Policy

2010 ◽  
Vol 38 (3) ◽  
pp. 667-683 ◽  
Author(s):  
Mike Nair-Collins
Keyword(s):  
Public Policy ◽  
Brain Death ◽  
Brain Stem ◽  
Real World ◽  
Determination Of Death ◽  
Whole Brain ◽  
Legislative Changes ◽  
The Brain ◽  
Irreversible Cessation

The 1981 Uniform Determination of Death Act (UDDA) states:An individual that has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brain stem, is dead.The “whole-brain concept of death,” appealed to in the UDDA, has been roundly criticized for many years. However, despite a great deal of legitimate criticism in academic circles no real clinical or legislative changes have come about. At least one reason for this inertia is aptly stated by James Bernat, one of the principal and founding proponents of the brain death doctrine: “In the real world of public policy on biological issues, we must frequently make compromises or approximations to achieve acceptable practices and laws.” While acknowledging that the brain death doctrine is not flawless and that he and other proponents have been unable to address all valid criticisms, Bernat nonetheless maintains that the brain death doctrine is optimal public policy.

scholarly journals Peptide YY3–36 and Glucagon-Like Peptide-17–36 Inhibit Food Intake Additively

Endocrinology ◽  
2005 ◽  
Vol 146 (12) ◽  
pp. 5120-5127 ◽  
Author(s):  
Nicola M. Neary ◽  
Caroline J. Small ◽  
Maralyn R. Druce ◽  
Adrian J. Park ◽  
Sandra M. Ellis ◽  
...  
Keyword(s):  
Food Intake ◽  
Brain Stem ◽  
Low Dose ◽  
Arcuate Nucleus ◽  
Peptide Yy ◽  
High Dose ◽  
Hypothalamic Arcuate Nucleus ◽  
Inhibit Food Intake ◽  
Glucagon Like Peptide ◽  
The Brain

Peptide YY (PYY) and glucagon like peptide (GLP)-1 are cosecreted from intestinal L cells, and plasma levels of both hormones rise after a meal. Peripheral administration of PYY3–36 and GLP-17–36 inhibit food intake when administered alone. However, their combined effects on appetite are unknown. We studied the effects of peripheral coadministration of PYY3–36 with GLP-17–36 in rodents and man. Whereas high-dose PYY3–36 (100 nmol/kg) and high-dose GLP-17–36 (100 nmol/kg) inhibited feeding individually, their combination led to significantly greater feeding inhibition. Additive inhibition of feeding was also observed in the genetic obese models, ob/ob and db/db mice. At low doses of PYY3–36 (1 nmol/kg) and GLP-17–36 (10 nmol/kg), which alone had no effect on food intake, coadministration led to significant reduction in food intake. To investigate potential mechanisms, c-fos immunoreactivity was quantified in the hypothalamus and brain stem. In the hypothalamic arcuate nucleus, no changes were observed after low-dose PYY3–36 or GLP-17–36 individually, but there were significantly more fos-positive neurons after coadministration. In contrast, there was no evidence of additive fos-stimulation in the brain stem. Finally, we coadministered PYY3–36 and GLP-17–36 in man. Ten lean fasted volunteers received 120-min infusions of saline, GLP-17–36 (0.4 pmol/kg·min), PYY3–36 (0.4 pmol/kg·min), and PYY3–36 (0.4 pmol/kg·min) + GLP-17–36 (0.4 pmol/kg·min) on four separate days. Energy intake from a buffet meal after combined PYY3–36 + GLP-17–36 treatment was reduced by 27% and was significantly lower than that after either treatment alone. Thus, PYY3–36 and GLP-17–36, cosecreted after a meal, may inhibit food intake additively.

scholarly journals Comparison of Dosimetric Benefits of Three Precise Radiotherapy Techniques in Nasopharyngeal Carcinoma Patients Using a Priority-Classified Plan Optimization Model

2021 ◽  
Vol 11 ◽  
Author(s):  
Qiaoli Wang ◽  
Jiyong Qin ◽  
Ruixue Cao ◽  
Tianrui Xu ◽  
Jiawen Yan ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Nasopharyngeal Carcinoma ◽  
Brain Stem ◽  
Optimization Model ◽  
High Dose ◽  
Temporal Lobes ◽  
T Stage ◽  
Plan Optimization ◽  
The Brain ◽  
Better Than

IntroductionAlthough intensity-modulated radiotherapy (IMRT), volumetric-modulated arc therapy (VMAT) and tomotherapy (TOMO) are broadly applied for nasopharyngeal carcinoma (NPC), the best technique remains unclear. Therefore, this study was conducted to address this issue.MethodsThe priority-classified plan optimization model was applied to IMRT, VMAT and TOMO plans in forty NPC patients according to the latest international guidelines. And the dosimetric parameters of planning target volumes (PTVs) and organs at risk (OARs) were compared among these three techniques. The Friedman M test in SPSS software was applied to assess significant differences.ResultsThe median PGTVnx coverage of IMRT was the lowest (93.5%, P < 0.001) for all T categories. VMAT was comparable to TOMO in OARs clarified as priority I and II, and both satisfied the prescribed requirement. IMRT resulted in a relatively high dose for V25 and V30. Interestingly, subgroup analysis showed that the median PTV coverage of the three techniques was no less than 95% in the early T stage. The heterogeneity index (HI) of PGTVnx in VMAT was better than that in IMRT (P = 0.028). Compared to TOMO, VMAT showed a strong ability to protect eyesight and decrease low-dose radiation volumes. In the advanced T stage subgroup, TOMO numerically achieved the highest median PGTVnx coverage volume compared with VMAT and IMRT (93.61%, 91% and 90%, respectively). The best CI and HI of PCTV-1 were observed in TOMO. Furthermore, TOMO was better than VMAT for sparing the brain stem, spinal cord and temporal lobes (all P < 0.05). However, the median V5, V10, V15, V20 and V25 were significantly higher with TOMO than with VMAT (all P < 0.05).ConclusionIn the early T stage, VMAT provides a similar dose coverage and protection of OARs to IMRT, and there are no obvious advantages to choosing TOMO for NPC patients in the early T stage. TOMO may be recommended for patients in the advanced T stage due as it provides the largest dose coverage of PGTVnx and the best protection of the brain stem, spinal cord and temporal lobes. Additionally, more randomized clinical trials are needed for further clarification.

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