The diagnosis of brain death

Mood assessments of family caregivers of patients with severe brain injury in China

OBJECTIVES

Long-term care of severe brain injury patients places a significant mental burden on family caregivers, yet few studies have reported the situation in China. We aimed to describe the mood states of family caregivers of patients with severe brain injury and examine the influencing factors that affect caregivers' moods.

METHODS

Cross-sectional survey was used to assess the mood profiles of Chinese family caregivers between February 2019 and February 2020. Demographic data of caregivers and patients, the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder scale (GAD-7) were used to assess the level of depressive and anxiety symptoms. The quality of life score was also assessed by a visual analog scale, and the Coma Recovery Scale-Revised was used to assess the patient's consciousness.

RESULT

One hundred and one patients with severe brain injury (57 unresponsive wakefulness syndrome, UWS) between the age of 14 and 70 and their main family caregivers were enrolled in the study. Most caregivers displayed depressive (n = 62) and anxiety symptoms (n = 65), with 17 and 20 of these family caregivers reporting (moderately) severe depressive symptom and severe anxiety symptom, respectively. The caregiver's depressive symptom level significantly decreased as the patient's injury lasted longer (r =  - 0.208, P = 0.037). Moreover, the age of the patient negatively related to the levels of depressive (r =  - 0.310, P = 0.002) and anxiety symptoms (r =  - 0.289, P = 0.003) in caregivers. There was a significant positive correlation between anxiety and depressive symptoms scores in family caregivers (r = 0.838, P < 0.001). The higher the level of anxiety (r =  - 0.273, P = 0.006) and depressive symptoms (r =  - 0.265, P = 0.007), the worse the quality of life.

CONCLUSION

Many family caregivers of patients with severe brain injury experience various levels of anxiety and depressive symptoms in China. Tailor-made psychological help seems imperative. Researchers and doctors can provide information about patient's conditions to assist family members in discussing rehabilitation options for patients in different states of consciousness will help to ease anxiety of family caregivers.

Abortion, Brain Death, and Coercion

A "universalist" policy on brain death holds that brain death is death, and neurologic criteria for death determination are rightly applied to all, without exemptions or opt outs. This essay argues that advocates of a universalist brain death policy defend the same sort of coercive control of end-of-life decision-making as "pro-life" advocates seek to achieve for reproductive decision-making, and both are grounded in an illiberal political philosophy. Those who recognize the serious flaws of this kind of public policy with respect to abortion must apply the same logic to brain death.

Functional PET Neuroimaging in Consciousness Evaluation: Study Protocol

Ensuring a robust and reliable evaluation of coma deepness and prognostication of neurological outcome is challenging. We propose to develop PET neuroimaging as a new diagnostic and prognosis tool for comatose patients using a recently published methodology to perform functional PET (fPET). This exam permits the quantification of task-specific changes in neuronal metabolism in a single session. The aim of this protocol is to determine whether task-specific changes in glucose metabolism during the acute phase of coma are able to predict recovery at 18 months. Participation will be proposed for all patients coming for a standard PET-CT in our center in order to evaluate global cerebral metabolism during the comatose state. Legally appointed representative consent will be obtained to slightly modify the exam protocol: (1) ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) bolus plus continuous infusion instead of a simple bolus and (2) more time under camera to perform dynamic acquisition. Participants will undergo a 55-min fPET session with a 20% bolus + 80% infusion protocol. Two occurrences of three block (5-min rest, 10-min auditory stimulation and 10-min emotional auditory stimulation) will be performed after reaching equilibrium of FDG arterial concentration. We will compare the regional brain metabolism at rest and during the sessions of auditory and emotional auditory stimulation to search for a determinant of coma recovery (18 months of follow-up after the exam). Emotional auditory stimulation should induce an activation of: the auditory cortex, the consciousness areas and the neural circuitry for emotion (function to coma deepness). An activation analysis will be carried out to highlight regional brain activation using dedicated custom-made software based on Python statistical and image processing toolboxes. The association between activation levels and the Coma Recovery Scale-Revisited (CRS-R) will be assessed using multivariate analysis. If successful, the results from this study will help improve coma prognosis evaluation based on the pattern of neuronal metabolism at the onset of the pathology. The study protocol, rationale and methods are described in this paper.

What happens in the brain when we die? Deciphering the neurophysiology of the final moments in life

When do we die and what happens in the brain when we die? The mystery around these questions has engaged mankind for centuries. Despite the challenges to obtain recordings of the dying brain, recent studies have contributed to better understand the processes occurring during the last moments of life. In this review, we summarize the literature on neurophysiological changes around the time of death. Perhaps the only subjective description of death stems from survivors of near-death experiences (NDEs). Hallmarks of NDEs include memory recall, out-of-body experiences, dreaming, and meditative states. We survey the evidence investigating neurophysiological changes of these experiences in healthy subjects and attempt to incorporate this knowledge into the existing literature investigating the dying brain to provide valuations for the neurophysiological footprint and timeline of death. We aim to identify reasons explaining the variations of data between studies investigating this field and provide suggestions to standardize research and reduce data variability.

Case report: Absent fluorodeoxyglucose uptake in a dog with unexpected brain death

A 5-year-old male Maltese dog was presented with generalized tonic seizures and hypermetria. Multiple nodular subcortical cerebellar enhancements and meningeal enhancement were observed on magnetic resonance imaging. Fluorodeoxyglucose-positron emission tomography/computed tomography was performed due to suspicion of neoplastic disease, and no fluorodeoxyglucose uptake was observed in the intracranial structures. In PET images of this dog, absent fluorodeoxyglucose uptake was identified in the brain indicating no cerebral metabolism, strongly suggested brain death. The dog had no spontaneous breathing and no brainstem reflexes for more than 24 h after the termination of anesthesia. Through these results, this dog was diagnosed with unexpected brain death, and it is presumed that the cause was anesthesia. We report herein a case of brain death in a dog diagnosed using fluorodeoxyglucose-positron emission tomography/computed tomography.

Intracranial and Extracranial Evaluation

The vascular lab is an essential tool in diagnosing intracranial and extracranial disease including vasospasm from subarachnoid hemorrhage and carotid artery stenosis in the setting of stroke or transient ischemic attack. This article discusses the indications, protocol, and diagnostic criteria for transcranial doppler (TCD) and carotid artery duplex ultrasound. Intracranial and extracranial arterial testing by way of TCD and carotid imaging carries enormous implications and can provide life or death information. The learning curve for these techniques is steep but can be mastered with repetition and precise technique.

Can bispectral index be an early marker in the diagnosis of brain death?

BACKGROUND

The diagnosis of brain death is a clinical condition in which it is difficult to perform confirmatory tests due to the ineligible clinical status of the patient. Prior to confirmatory tests, the use of a BIS monitor to determine the time of brain death is important for organ transplants, cost-effectiveness and reducing stressful wait of the family.

OBJECTIVE

This study aimed to use BIS monitoring for early detection of brain death.

METHODS

BIS monitoring was performed in 12 patients who were clinically diagnosed with brain death in our intensive care unit during a two-year period.

RESULTS

All patients had diffuse brain injury. The BIS score was zero in all patients. However, two patients could not be legally diagnosed with brain death because confirmatory tests could not be performed due to the clinical status. In one patient, the BIS score was zero and blood flow was present on the first computed tomography angiography of the brain; however, the cerebral blood flow was absent on the second imaging after two days.

CONCLUSION

It was believed that BIS monitoring could be a parameter to use for detection of brain death in patients with severe brain injury. However, future research is needed in this regard.

AC, da Cruz Jr. LCH. The role of neuroimaging in the determination of brain death

Brain death is the irreversible cessation of all brain function. Although protocols for its determination vary among countries, the concept of brain death is widely accepted, despite ethical and religious issues. The pathophysiology of brain death is related to hypoxia and ischemia in the setting of extensive brain injury. It is also related to the effects of brain edema, which increases intracranial pressure, leading to cerebral circulatory arrest. Although the diagnosis of brain death is based on clinical parameters, the use of neuroimaging to demonstrate diffuse brain injury as the cause of coma prior to definitive clinical examination is a prerequisite. Brain computed tomography (CT) and magnetic resonance imaging (MRI) demonstrate diffuse edema, as well as ventricular and sulcal effacement, together with brain herniation. Angiography (by CT or MRI) demonstrates the absence of intracranial arterial and venous flow. In some countries, electroencephalography, cerebral digital subtraction angiography, transcranial Doppler ultrasound, or scintigraphy/single-photon emission CT are currently used for the definitive diagnosis of brain death. Although the definition of brain death relies on clinical features, radiologists could play an important role in the early recognition of global hypoxic-ischemic injury and the absence of cerebral vascular perfusion.

Simulation-Based Training Improves Fellows' Competence in Brain Death Discussion and Declaration

BACKGROUND

Despite well-defined American Academy of Neurology guidelines for death by whole brain criteria (brain death), there is marked variability in national practice, which some have attributed to lack of formal education. Further, communication with surrogates and families about brain death is integral to brain death declaration. As such, we developed a targeted brain death curriculum combining didactics and simulation-based education to improve examination and subsequent communication skills with families.

METHODS

Multidisciplinary critical care fellows participated in (1) didactic and case-based curriculum, (2) brain death simulated examination (SimMan3G mannequin), and (3) a standardized family scenario with delivery of a brain death diagnosis to a surrogate "family member". Fellows completed a precurriculum and postcurriculum multiple choice knowledge test and survey (Likert 1 to 10 scale) evaluating measures regarding diagnosis and communication of brain death. t Test and 2-tailed Wilcoxon signed rank test were used for statistical analysis (P<0.05).

RESULTS

Thirteen critical care fellows participated in the curriculum. Most fellows [80% (N=12)] had only participated in 0 to 5 brain death declarations before this intervention. There was significant improvement across all measures: self-rated knowledge (P=0.004), perceived knowledge relative to peers (P=0.002), confidence (P=0.001), and comfort (P=0.001) with performing a brain death exam, and comfort with family discussion (P=0.01). Objective test scores improved from 56 to 73% after simulation (P=0.004). All fellows found the curriculum beneficial.

CONCLUSION

Trainees may lack sufficient exposure to brain death education. Didactics with simulation-based education can improve objective knowledge and subjective measures of comfort with brain death declaration and surrogate communication.

Effects of Terlipressin on Management of Hypotensive Brain-Dead Patients Who are Potential Organ Donors: A Retrospective Study

Background: Administration of terlipressin can reverse hypotension in potential organ donors with norepinephrine-resistance. The aim of this study was to determine the effects of terlipressin on the hemodynamics, liver function, and renal function of hypotensive brain-dead patients who were potential organ donors.

Methods: A retrospective study was conducted by using the ICU database of one hospital. 18 patients in a total of 294 brain-dead cases were enrolled and administered terlipressin intravenously. All physiological parameters of recruited patients were obtained at baseline, 24 and 72 h after administration, and immediately before organ procurement.

Results: Terlipressin induced significant increases in mean arterial pressure (MAP) from 69.56 ± 10.68 mm Hg (baseline) to 101.82 ± 19.27 mm Hg (immediately before organ procurement) and systolic blood pressure (SBP) from 89.78 ± 8.53 mm Hg (baseline) to 133.42 ± 26.11 mm Hg (immediately before organ procurement) in all patients. The increases in MAP were accompanied by significant decreases in heart rate (HR) from 113.56 ± 28.43 bpm (baseline) to 83.89 ± 11.70 bpm (immediately before organ procurement), which resulted in the decrease of norepinephrine dose over time from 0.8 ± 0.2 μg/kg/min (baseline) to 0.09 ± 0.02 μg/kg/min (immediately before organ procurement). There were no changes in central venous pressure, liver function including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and bilirubin. Renal function, assessed by serum creatinine (SCr), urine output (UOP), creatinine clearance rate (CCr), and estimated glomerular filtration rate (eGFR), improved significantly.

Conclusion: Our analysis of brain-dead patients with hypotension indicates that administration of terlipressin can significantly increases MAP, SBP, UOP, CCr, and eGFR, while decreases HR and Scr. Terlipressin appears to help maintain hemodynamic stability, reduce vasoactive support, and improve renal function.

The ethics of neurologically complicated pregnancies

Bioethical conflicts in pregnancy are distinguished from those in other areas of medicine due to competing interests between mother and fetus because of their shared biology. Historically, prior to the advent of fetal therapy and advances in medical technology, the maternal-fetal complex was considered to be a single entity. With advances in medicine, treatment options can now be directed at both the mother and the fetus, and a duality has evolved in the maternal-fetal unit. Thus at some point during pregnancy, two individuals rather than just one are the responsibility of the physician. In determining how to properly care for the pregnant woman with a neurologic condition, therapeutic choices must take into consideration the impact a treatment will have on both the mother and the fetus. Since what benefits one may harm the other, tension results from the need to choose. This chapter will highlight ethical conflicts arising at the interface of obstetrics and neurology. We will delve into situations where difficult reproductive and therapeutic decisions must be made in pregnant women with intellectual disabilities, stroke, brain tumors, and epilepsy. The complexity of brain death in pregnancy will be analyzed, acknowledging the influence of politics, law, and religion that bears on ethical decision-making. In approaching ethical dilemmas encountered in pregnancies complicated by neurologic conditions, frameworks based on principles, virtues, care, and feminist ethics, and case precedents will be applied to facilitate ethically appropriate shared decision-making. We hope that this chapter will provide valuable guidance for providers caring for this complex obstetric population.

Intracerebral Hemorrhage: A Common yet Disproportionately Deadly Stroke Subtype

Spontaneous intracerebral hemorrhage (ICH) is a medical emergency and is disproportionately associated with higher mortality and long-term disability compared with ischemic stroke. The phrase "time is brain" was derived for patients with large vessel occlusion ischemic stroke in which approximately 1.9 million neurons are lost every minute. Similarly, this statement holds true for ICH patients due to a high volume of neurons that are damaged at initial onset and during hematoma expansion. Most cases of spontaneous ICH pathophysiologically stem from chronic hypertension and rupture of small perforating vessels off of larger cerebral arteries supplying deep brain structures, with cerebral amyloid angiopathy being another cause for lobar hemorrhages in older patients. Optimal ICH medical management strategies include timely diagnosis, aggressive blood pressure control, correction of underlying coagulopathy defects if present, treatment of cerebral edema, and continuous assessment for possible surgical intervention. Current strategies in the surgical management of ICH include newly developed minimally invasive techniques for hematoma evacuation, with the goal of mitigating injury to fiber tracts while accessing the clot. We review evidence-based medical and surgical management of spontaneous ICH with the overall goal of reducing neurologic injury and optimizing functional outcome.

[Irreversible loss of brain function : Requirements and Clinical diagnosis]

Brain death (irreversible loss of brain function), according to German regulations, is investigated exclusively by qualified specialists in a strictly hierarchical three-step pattern and a four-eyes principle. In step 1 all necessary prerequisites are to be checked and the pathophysiology of brain damage has to be classified. Step 2 comprises the clinical investigation of reactivity to external stimuli and the upper, middle and lower brain stem reflexes including apnea testing. Step 3 exclusively checks for irreversibility of this condition. The latter is achieved by appropriate technical investigations or by repeated clinical examinations within context-specified intervals (range 12-72 h). However, exclusion of contributing primarily infratentorial pathologies is necessary to avoid limitations of the clinical findings. In this paper, both the initiation of brain death diagnostics and the approved clinical tests regarding to their execution, their alternatives and limits are presented and special situations like conditions with extracorporeal membrane oxygenation (ECMO) are also examined.

Measuring Perfusion: Intravoxel Incoherent Motion MR Imaging

The signal acquired in vivo using a diffusion-weighted MR imaging (DWI) sequence is influenced by blood motion in the tissue. This means that perfusion information from a DWI sequence can be obtained in addition to thermal diffusion, if the appropriate sequence parameters and postprocessing methods are applied. This is commonly regrouped under the denomination intravoxel incoherent motion (IVIM) perfusion MR imaging. Of relevance, the perfusion information acquired with IVIM is essentially local, quantitative and acquired without intravenous injection of contrast media. The aim of this work is to review the IVIM method and its clinical applications.

Turkish validation of the Jefferson scale of empathy for nurses seeking kidney donations in intensive care units

AIM

To find the answer to the question: is a high level of empathy of intensive care nurses effective in increasing organ donation?

MATERIALS AND METHODS

This study was performed with nurses who had been working in intensive care units for at least 1 year in 17 hospitals in 8 provinces in Turkey. Jefferson Scale of Empathy and the other questionnaire forms were sent to the nurses by email, and completed forms from those who accepted to participate in the study were also received by email.

RESULTS

There was a positive significant relationship between donor declaration and empathy score. An increase was observed in empathy score as donor declaration increased. Cronbach's alpha coefficient of Jefferson Scale of Empathy (JSE) in general was α = 0.71. JSE is an acceptable tool of measurement in terms of internal consistency. Turkish validation of JSE was provided.

DISCUSSION

There was a direct relationship between empathy levels of intensive care nurses and donor declarations and organ finding. Therefore, it can be assumed that a preference for nurses with a high level of empathy to work in intensive care units would be effective in increasing organ donations. Alternatively, empathy increasing trainings during in-service trainings and seminars for intensive care nurses may increase organ donation and thus provide hope for patients awaiting organ donations.

A Systematic Literature Review on Depopulation Methods for Swine

Swine mass depopulation refers to the destruction of large numbers of pigs and may include not only animals affected with a disease but also healthy pigs in a facility or surrounding areas. Emerging applications of mass depopulation include reducing welfare issues associated with slaughter delays, which was observed in the United States in 2020 as a result of the Coronavirus disease (COVID-19) pandemic. The objectives of this review were to summarize the available literature on swine depopulation methods and to highlight critical gaps in knowledge. Peer-reviewed articles were identified through a systematic search in electronic databases including Web of Science, MEDLINE, and PubMed. A total of 68 publications were assessed. Gaseous carbon dioxide inhalation was the most commonly reported depopulation method for both small- and large-scale trials. Measurements of consciousness state, which serves to assess suffering and humaneness, appeared to be lacking in a high proportion of the studies. None of the published studies demonstrated an ideally reliable and safe way to induce rapid unconsciousness in large groups of pigs. Development of rapid mass depopulation methods applicable to large groups of pigs is necessary to provide industry partners with suitable and low-cost emergency preparedness procedures while adhering to personnel safety and animal welfare standards. Lastly, there is an urgent need to standardize comprehensive reporting guidelines for depopulation studies.

[Irreversible loss of brain function-Part 1: pitfalls in clinical diagnosis]

A significant change in the fourth update of the German guidelines on determining brain death is that it includes an explicit profile of requirements on physicians involved in ILBF diagnosis. These requisite qualification criteria have also been formulated due to the fact that, in many hospitals, ILBF diagnosis is only rarely carried out and, as a result, uncertainty frequently arises. Typical difficulties emerge at all stages of ILBF diagnosis, and numerous relevant pitfalls arise that need to be taken into consideration and which might also be relevant in the selection of the method(s) to detect irreversibility. The approaches presented here are suited to achieving a valid result in the evaluation of equivocal ILBF.

A Qualitative Identification of Gaps in Understanding About Brain Death Among Trainees, Health Care Personnel and Families at an Academic Medical Center

Background and Purpose

Death by whole brain criteria (brain death) is a clinical diagnosis. We sought to identify aspects of brain death that were unclear to both health care personnel and patient families.

Methods

Institutional review board approved cross-sectional survey study of attendings, medical trainees (residents and fellows), senior medical students, advanced practice providers (APPs), and critical care nursing (registered nurses [RNs]) at a tertiary referral center over 6 months (March 2018 to September 2018). Surveys were completed on paper or electronically. Participants supplied the top 3 of (1) their own personal questions regarding brain death and (2) questions received from patient families about brain death from a prepared list of questions.

Results

Two hundred twenty-nine individuals participated in the survey, with a response rate of 46%. Participation rates in brain death declaration among attendings (92%), RNs (84%), APPs (100%), and trainees of which included fellows (92%) and residents (85%) were high. Most frequently asked questions by trainees and health care personnel were "What are brain death mimics?" and "What is the gold standard testing?". Questions received from patient families most commonly include "What is brain death?" and "Is brain death reversible?". All medical students had questions about brain death. Greater than 75% of attendings endorsed having questions regarding brain death.

Conclusion

Many health care personnel are involved with brain death declaration, but there are gaps in their understanding about fundamentals regarding brain death. We identify a need for early and targeted brain death education regarding brain death and family communication for various members of the health care profession.

Global Scientific Outputs of Brain Death Publications and Evaluation According to the Religions of Countries

In 1950s, the concept of brain death, which began to be discussed primarily in terms of medicine and then in terms of religion, law, and ethics, became a central topic in all world countries as it was an early diagnosis of death. Despite the fact that brain death (BD) diagnosis is of importance for benefitting from organ and tissue transplantation of patients in the world, the literature still involves no bibliometric studies that made a holistic evaluation of the publications about this issue. The present study aims to investigate the top-cited articles about BD published between 1980 and 2018, identify the citation collaboration of the journals, demonstrate the collaboration between the countries, define the relationship between organ transplantation and BD, and reveal the latest developments and trend topics about this issue. In addition, this study aims to investigate the relationship between religions of countries and brain death publication productivity. Documents for bibliometric analysis were downloaded from Web of Science. The literature search was performed using the keywords "brain death/dead" during 1980-2018. The correlations between gross domestic product (GDP), Human Development Index (HDI) and publication productivity of the countries on BD were investigated with Spearman's correlation coefficient. There was a high-level, statistically significant correlation between the number of publications and GDP, and HDI and the number of publications about BD (r = 0.761, p < 0.001; r = 0.703, p < 0.001). The USA was the top country in terms of publication productivity, which was followed by developed countries such as Germany, Japan, France, and Spain. However, the contribution of the undeveloped or developing countries such as China, Brazil, Turkey, Iran, and South Africa was found to be considerably important. While many people in the world die with undamaged organs, many other people die needing those organs. Therefore, it is considered that the collaborations and thus multidisciplinary studies about BD should be increased in the world countries, and the countries should be involved in bigger collaborations instead of little clusters. Especially, Muslim countries should be encouraged to do research and publish studies about the issues of brain death and organ transplantation.

What to exclude when brain death is suspected

BACKGROUND

With advances in critical care and organ donation, diagnosis of brain death is gaining importance. We aimed to assess potential brain death confounders from the literature, elucidating clinical presentation and diagnostic approaches in these cases.

METHODS

PubMed and Embase were screened using 37 predefined search terms to identify suitable articles reporting cases, case series, or cohort studies in adults.

RESULTS

Out of 4769 articles, 40 case reports or case series describing 45 patients with 19 critical conditions were identified. Mortality was 11% and full recovery 33%. Intoxications (42%; mainly anti-seizure drugs and baclofen) and polyneuritis (37%) were most frequent. Brainstem reflex tests were reported in 96%, apnoea test in 16% and ancillary tests in all but one patient. Full recovery mainly occurred with intoxications. Quality of evidence regarding frequency of confounders is very low and risk of bias high.

CONCLUSIONS

Brain death confounders are infrequently reported and formal studies are lacking. Mainly younger patients with polyneuritis and intoxications are described. As outcome, especially in the latter, is often favourable, high awareness and strict adherence to guidelines is crucial. The importance of identifying pathologies compatible with extensive and irreversible brain damage before proceeding to diagnostic tests should be emphasized.

Identification of Hemodynamic Risk Factors for Apnea Test Failure During Brain Death Determination

OBJECTIVE

An apnea test is essential step for diagnosing brain death and is known to be relatively safe. However, various complications such as hypoxia, arrhythmias, and hypotension could occur. Herein, we identified risk factors of failed apnea test and determined their optimal cutoff values.

METHODS

We retrospectively analyzed 512 patients of apnea test to diagnose brain death and classified them into 2 groups according to success or failure of the test. Demographic characteristics, value of arterial blood gas analysis, and systolic blood pressure (SBP) were collected, and alveolar-arterial gradient (A-a gradient) and Pao₂/fraction of inspired oxygen ratio were calculated to evaluate the respiratory status.

RESULTS

A total of 484 patients completed the apnea test, and the test was aborted in 28 patients because of hypotension or refractory hypoxemia. The SBP, pH, Pao₂, and Pao₂/fraction of inspired oxygen ratio were higher in success group, whereas A-a gradient was lower. In multivariate analysis, low SBP (odds ratio [OR], 0.976; 95% CI, 0.958-0.994; P = .01), low pH (OR, 0.004; 95% CI, 0.000-0.184; P = .005), and elevated A-a gradient (OR, 1.005; 95% CI, 1.003-1.008; P = .001) were associated with apnea test failure. The optimal cutoff values to predict the test failure were 105.0 mm Hg for pretesting SBP, 7.326 for pretesting pH, and 556.4 mm Hg for pretesting A-a gradient.

CONCLUSION

Early recognition and aggressive management for the risk factors are important to reduce failure rates of apnea test and consequently improve outcomes of organ procurement.

Impact of Skull Defects on the Role of CTA for Brain Death Confirmation

BACKGROUND AND PURPOSE

Intracranial pressure modifications caused by a skull defect, such as craniectomy or craniotomy, may change the hemodynamics and decrease the accuracy of CTA to confirm brain death. This study aimed to evaluate the impact of a skull defect and the interpretation criteria of images on this diagnostic test.

MATERIALS AND METHODS

A series of consecutive patients with a clinical diagnosis of brain death underwent CTA (case group), while the control group comprised patients with acute ischemic stroke in the same period. CTA criteria adopted to confirm brain death were the absence of opacification of the M4 branches and internal cerebral veins. The evaluation also included the presence of "stasis filling." Cases were stratified as intact skull, craniotomy, and craniectomy. Three neuroradiologists evaluated all examinations independently.

RESULTS

In the case group, according to the Frampas criteria, the sensitivity of CTA to confirm brain death was 95.5% in patients with intact skull, 87.5% with craniotomy, and 60% with craniectomy. False-negative diagnoses of brain death were 15.6%, related to stasis filling in 71.4% (P < .001). However, according to the "modified Frampas criteria," the sensitivity of CTA to confirm brain death was 100% in patients with intact skull, 93.8% with craniotomy, and 80% with craniectomy. False-negative diagnoses of brain death were found in 6.2% of patients, and there was no stasis filling. CTA showed 100% specificity in the control group. There were no disagreements among observers.

CONCLUSIONS

CTA had a high diagnostic accuracy and reproducibility to confirm brain death in patients with an intact skull. The modified Frampas criteria increased the sensitivity of CTA, particularly in patients with a skull defect. A concurrent skull defect, especially craniectomy, can decrease the sensitivity of CTA to confirm brain death.

Use of Venous Pco2 in Determination of Death by Neurological Criteria in Children

BACKGROUND

Compare the increase in partial pressure of carbon dioxide (Pco₂) from venous blood samples with that of arterial blood samples during apnea challenge test in determination of death by neurological criteria.

METHODS

Prospective nonrandomized cohort study in tertiary care pediatric intensive care unit. Patients older than 37 week's gestation admitted to PICU with irreversible brain injury at the time when attending physician will perform apnea challenge test as part of brain death examination from October 2015 till September 2017.

INTERVENTIONS

None.

RESULTS

The primary outcome was to measure and compare the increase in Pco₂ from venous blood samples with that from arterial blood samples during apnea challenge test. A total of nine apnea challenge tests from seven patients (ages five months to 17 years) were included in the study. Pco₂ in venous blood sample increased less than that in arterial blood samples (venous, 26.1 mm Hg; S.D., 10.1; 95% confidence interval, 18 to 34 mm Hg; arterial, 33.9 mm Hg; S.D., 12.0; 95% confidence interval, 24 to 43 mm Hg) (P = 0.02).

CONCLUSION

Postapnea challenge test Pco₂ of 60 mm Hg along with increase of 20 mm Hg in venous blood sample correlated to Pco₂ greater than 60 mm Hg along with increase of greater than 20 mm Hg in arterial blood sample. Further studies are warranted to assess if current recommendations for determination of death by neurological criteria in children can be modified to allow for use of venous blood samples as an alternate to arterial blood samples.

Death by neurologic criteria: pathophysiology, definition, diagnostic criteria and tests

Death by neurologic criteria is an irreversible sequence of events culminating in permanent cessation of cerebral functions. In this context, there are no responses arising from the brain, no cranial nerve reflexes nor motor responses to pain stimuli, and no respiratory drive. The diagnosis of death by neurologic criteria implies that there is clinical evidence of the complete and irreversible cessation of brainstem and cerebral functions. The diagnosis, confirmation, and certification of death are core skills for medical practitioners. The aim of this review is to discuss the pathophysiology and definition of death by neurological criteria, describing the clinical assessment, and the use of ancillary tests for the diagnosis of brainstem death.

Brain Death at Fifty: Exploring Consensus, Controversy, and Contexts

This special report is published in commemoration of the fiftieth anniversary of the "Report of the Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death," a landmark document that proposed a new way to define death, with implications that advanced the field of organ transplantation. This remarkable success notwithstanding, the concept has raised lasting questions about what it means to be dead. Is death defined in terms of the biological failure of the organism to maintain integrated functioning? Can death be declared on the basis of severe neurological injury even when biological functions remain intact? Is death essentially a social construct that can be defined in different ways, based on human judgment? These issues, and more, are discussed and debated in this report by leading experts in the field, many of whom have been engaged with this topic for decades.

Delays in Brain Death Certification in an Opt-out Deceased Organ Donation System: Causes, Ethical Problems, and Avoidance

Brain death certification can be a clinically and ethically challenging affair. Healthcare workers are expected to refer patients for brain death certification to identify potential organ donors, but family members may be ill-prepared for this turn of events. Already distraught families may not appreciate delays in brain death certification, but such delays are common because of the need to manage the patient's altered physiological state to allow testing. Opportunities for donation are sometimes lost because of the unnecessary delay. With focus on an opt-out organ donation law, we discuss causes of delays in brain death certification, and the ethical issues faced by clinicians in using tests to certify patients. To resolve the issues, we argue for the use of supplementary confirmatory tests as part of a more protocol-driven approach to brain death certification to avoid delays. Such tests should be regarded as part of the donation process funded by the state.

Rapid Brain Death following Cardiac Arrest without Intracranial Pressure Rise and Cerebral Circulation Arrest

We describe here an unusual case of brain death following cardiac arrest. Brain electric activity had totally ceased, allowing the confirmation of brain death, despite normal cerebral blood flow (assessed by both transcranial doppler and tomodensitometry) and no evidence of intracranial hypertension. In our case, a residual electric activity was assessed at admission and lesions worsened on imaging during ICU stay, suggesting that part of the neuronal damage occurred after brain reperfusion. All these elements suggest BD rather by cellular toxicity than intracranial pressure elevation.

The Role of Neuroimaging in the Determination of Brain Death

BACKGROUND AND PURPOSE

Brain death determination (BDD) is primarily a clinical diagnosis, where death is defined as the permanent loss of brainstem function. In scenarios where clinical examinations are inaccurate, ancillary imaging tests are required. The choice of ancillary imaging test is variable, but the common denominator for all of them is to establish a lack of cerebral blood flow. The purpose of this study was to compare the diagnostic accuracy and interrater reliability of different ancillary imaging tests used for BDD.

METHODS

Archival data were retrospectively analyzed for all patients who underwent any ancillary imaging test for BDD at our institution. The results of ancillary imaging tests were compared with, the reference standard, the clinical checklist for declaration of brain death. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of different ancillary imaging tests for BDD were performed. Interobserver agreement between two observers was measured using kappa statistics for each of the imaging modalities.

RESULTS

A total of 74 patients underwent 41 computer tomography perfusion (CTP), 54 CT angiogram, 15 radionuclide scans, 1 cerebral angiogram, 3 magnetic resonance imaging, and 71 nonenhanced CT (NECT) head for BDD. All ancillary tests (except NECT head) showed 100% specificity and PPV. CTP had the highest sensitivity and NPV. All ancillary imaging tests demonstrated very high interrater reliability.

CONCLUSIONS

The uses of ancillary imaging tests for BDD are increasing. Within this study's limitations, CTP followed by radionuclide scan were found to be the most accurate and reliable ancillary imaging test for BDD.

Definition of Terms Used in Limitation of Treatment and Providing Palliative Care at the End of Life: The Indian Council of Medical Research Commission Report

BACKGROUND

Indian hospitals, in general, lack policies on the limitation of inappropriate life-sustaining interventions at the end of life. To facilitate discussion, preparation of guidelines and framing of laws, terminologies relating to the treatment limitation, and providing palliative care at the end-of-life care (EOLC) need to be defined and brought up to date.

METHODOLOGY

This consensus document on terminologies and definitions of terminologies was prepared under the aegis of the Indian Council of Medical Research. The consensus statement was created using Nominal Group and Delphi Method.

RESULTS

Twenty-five definitions related to the limitations of treatment and providing palliative care at the end of life were created by reviewing existing international documents and suitably modifying it to the Indian sociocultural context by achieving national consensus. Twenty-five terminologies defined within the scope of this document are (1) terminal illness, (2) actively dying, (3) life-sustaining treatment, (4) potentially inappropriate treatment, (5) cardiopulmonary resuscitation (CPR), (6) do not attempt CPR, (7) withholding life-sustaining treatment, (8) withdrawing life-sustaining treatment, (9) euthanasia (10) active shortening of the dying process, (11) physician-assisted suicide, (12) palliative care, (13) EOLC, (14) palliative sedation, (15) double effect, (16) death, (17) best interests, (18) health-care decision-making capacity, (19) shared decision-making, (20) advance directives, (21) surrogates, (22) autonomy, (23) beneficence, (24) nonmaleficence, and (25) justice.

Evaluation of Two Models of Non-Penetrating Captive Bolt Devices for On-Farm Euthanasia of Turkeys

Simple Summary

Animal care guidelines for livestock and poultry require farms to have euthanasia plans in place for birds that are sick, injured, or unable to access feed and water. Killing methods considered to be humane are those that induce rapid insensibility (stun) and result in brain death leading to irreversible respiratory and cardiac arrest. Therefore, the evaluation of the effectiveness of a killing method generally focuses on measures of insensibility and brain death. Non-penetrating captive bolt devices are intended to deliver sufficient force and energy to the head to result in immediate insensibility and brain death without penetrating the skin. We evaluated the effectiveness of two models of non-penetrating captive bolt devices when applied by stock people to different sizes and ages of turkeys, using signs of insensibility corroborated by ante- and post- mortem evaluation of brain damage. Both non-penetrating captive bolt devices used in this study were found to be highly effective at inducing immediate insensibility and would be appropriate for on-farm euthanasia of turkeys of various ages and size.

Abstract

On-farm euthanasia is a critical welfare issue in the poultry industry and can be particularly difficult to perform on mature turkeys due to their size. We evaluated the efficacy of two commercially available non-penetrating captive bolt devices, the Zephyr-EXL and the Turkey Euthanasia Device (TED), on 253 turkeys at three stages of production: 4–5, 10, and 15–20 weeks of age. Effectiveness of each device was measured using both ante- and post-mortem measures. Application of the Zephyr-EXL resulted in a greater success rate (immediate abolishment of brainstem reflexes) compared to the TED (97.6% vs. 89.3%, p = 0.0145). Times to last movement (p = 0.102) and cardiac arrest (p = 0.164) did not differ between devices. Ante- and post-mortem measures of trauma and hemorrhage were highly correlated. Skull fractures and gross subdural hemorrhage (SDH) were present in 100% of birds euthanized with both the Zephyr-EXL and TED devices. Gross SDH scores were greater in birds killed with the Zephyr-EXL than the TED (p < 0.001). Microscopic SDH scores indicated moderate to severe hemorrhage in 92% of turkeys for the Zephyr-EXL and 96% of turkeys for the TED, with no difference between devices (p = 0.844). Overall, both devices were highly effective inducing immediate insensibility through traumatic brain injury and are reliable, single-step methods for on-farm euthanasia of turkeys.

Organ Transplantation in Iran; Current State and Challenges with a View on Ethical Consideration

Organ transplantation is a new issue in medical science. It is an important achievement and a sign of the progression and ability of medical centers around the world. Governments, populations, the medical community and people involved in culture, art, and media all have a decisive role in the culture of organ donation, which is the only way to guarantee that the healthy organs of a brain-dead person can continue to work and save the lives of people in need of organ transplantation. The brain death phenomenon and its possible application in organ transplantation, while offering new hope for the salvation of a number of patients, has led to many ethical, cultural, and legal issues. Ethical issues in organ transplantation are very complicated due to many social factors such as religion, culture, and traditions of the affected communities. The ethical and legal points of removing organs from the body of a living or cadaveric source, the definition of brain death, the moral and legal conditions of the donor and the recipient, and the financial relationship between them and many others, are all critical issues in organ transplantation. While there may be no available explicit solution to these issues, they should be rigorously considered by the experts. Efforts to systematically eliminate barriers and solve problems in organ transplantation, can not only reduce the costs of maintaining brain-dead patients and encourage patients that need organ transplantation but can also prevent immoral and illegal activities. In this paper, we have reviewed the most important and current challenges in organ transplantation with a view to the ethical considerations, and we have suggested some strategies to extend it in Iran.

Brain Dead Presentation of Snake Bite

Snakebite is considered as a significant public health problem contributing considerably to morbidity and mortality. A neurotoxic snake bite can present from mild ptosis to complete paralysis with external and internal ophthalmoplegia. Three patients presented in emergency intubated outside with deeply comatose, fixed dilated pupil, and absent doll's eye reflex mimicking as brain dead.

False-Positive Diagnosis of Brain Death Following the Pediatric Guidelines: Case Report and Discussion

A 2-year-old boy with severe head trauma was diagnosed brain dead according to the 2011 Pediatric Guidelines. Computed tomographic (CT) scan showed massive cerebral edema with herniation. Intracranial pressures were extremely high, with cerebral perfusion pressures around 0 for several hours. An apnea test was initially contraindicated; later, one had to be terminated due to oxygen desaturation when the Pco₂ had risen to 57.9 mm Hg. An electroencephalogram (EEG) was probably isoelectric but formally interpreted as equivocal. Tc-99m diethylene-triamine-pentaacetate (DTPA) scintigraphy showed no intracranial blood flow, so brain death was declared. Parents declined organ donation. A few minutes after withdrawal of support, the boy began to breathe spontaneously, so the ventilator was immediately reconnected and the death declaration rescinded. Two hours later, life support was again removed, this time for prognostic reasons; he did not breathe, and death was declared on circulatory-respiratory grounds. Implications regarding the specificity of the guidelines are discussed.

Brain Death

Death determined by neurologic criteria, commonly referred to as "brain death," occurs when function of the entire brain ceases, including the brain stem. Diagnostic criteria for brain death are explicit but controversy exists regarding nuances of the evaluation and potential confounders of the examination. Hospitals and ICU teams should carefully consider which clinicians will perform brain death testing and should use standard processes, including checklists to prevent diagnostic errors. Proper diagnosis is essential because misdiagnosis can be catastrophic. Timely, accurate brain death determination and aggressive physiologic support are cornerstones of both good end-of-life care and successful organ donation.

Pentobarbital Removal During Continuous Venovenous Hemofiltration: Case Report and Review of the Literature

BACKGROUND:

Renal replacement therapy may enhance the elimination of barbiturates. Pentobarbital clearance during continuous venovenous hemofiltration (CVVH) has not been described previously. We report a patient case involving the measurement of serial pentobarbital levels during CVVH and review relevant literature characterizing extracorporeal pentobarbital elimination.

METHODS:

The following is a retrospective report of a previously healthy 26-year-old woman who sustained a severe traumatic brain injury (TBI) and required administration of pentobarbital on hospital day 0 for intracranial pressure (ICP) control. Given concern for interference with the patient's ongoing neurologic assessments, pentobarbital was discontinued on hospital day 4. The patient's hospital course was complicated by acute kidney injury (AKI), requiring initiation of CVVH on hospital day 5. Daily serum pentobarbital levels were obtained during CVVH.

RESULTS:

While on CVVH, the patient's estimated pentobarbital clearance ranged from 6 to 44 mL/min and the elimination half-life ranged from 17.7 to 65.9 hours. Based on reductions in pentobarbital clearance during CVVH interruption, the elimination of drug was dependent upon extracorporeal removal in this patient. CVVH facilitated pentobarbital elimination in a manner approaching endogenous clearance in healthy individuals.

CONCLUSION:

We report clinically significant pentobarbital removal by CVVH in a patient with severe TBI. Application of CVVH may expedite reliable neurologic assessments and facilitate the application of clinical brain death examination following pentobarbital exposure.

Medical Training and the Brain Death Exam: A Single Institution's Experience

BACKGROUND

Clinicians may have limited opportunities to perform neurological determination of death (NDD, or brain death) certification during their training. This study aimed to evaluate the level of resident exposure to the brain death exam at a large-volume donor hospital.

METHODS

In March 2014, we adapted a dual-physician model for NDD certification at our institution to improve resident education regarding NDD. To evaluate the incidence of resident exposure, we collected examiner information from all brain death exams conducted between January 2014 and July 2015. Organ procurement, family authorization, and brain death intervals were also collected to evaluate the impact of NDD timeliness on organ donation.

RESULTS

A total of 68 patients who met NDD criteria were included in this study. For these patients, 127 brain death exams were performed, 108 (85%) by a critical care attending physician or fellow, 9 (7%) by a neurology resident, and 7 (6%) by a neurosurgery resident. Exposure rates for neurology and neurosurgery residents were approximately 0.22 and 0.20 exams/resident/year, respectively. The median brain death interval between exams was 1.0 hours (interquartile range, 0.0-2.5) hours. Resident involvement, time between exams, and dual exams were all found to be nonsignificant correlates of organ authorization and family refusal.

CONCLUSIONS

Neurology and neurosurgery residents may be limited in their exposure to the brain death exam during training. High-volume donor hospitals may be able to complete 2 exams for NDD certification in a timely manner without detrimentally influencing organ authorization or family refusal rates.

Early detection of brain death using the Bispectral Index (BIS) in patients treated by extracorporeal cardiopulmonary resuscitation (E-CPR) for refractory cardiac arrest

BACKGROUND

Despite increasing use of extracorporeal cardiopulmonary resuscitation (E-CPR) for treatment of refractory cardiac arrest patients, prognosis remains dismal, often resulting in brain-death. However, clinical assessment of brain-death occurence is difficult in post-cardiac arrest patients, sedated, paralyzed, under mild therapeutic hypothermia (MTH). Our objective was to assess the usefulness of Bispectral-Index (BIS) monitoring at bedside for an early detection of brain-death occurrence in refractory cardiac arrest patients treated by E-CPR.

METHODS

This prospective study was performed in an intensive care unit of an university hospital. Forty-six patients suffering from refractory cardiac arrest treated by E-CPR were included. BIS was continuously recorded during ICU hospitalization. Clinical brain-death was confirmed when appropriate by EEG and/or cerebral CT angiography.

RESULTS

Twenty-nine patients evolved into brain-death and had average BIS values under MTH and after rewarming (temperature ≥35°C) of 4 (0-47) and 0 (0-82), respectively. Among these, 11 (38%) entered into a procedure of organs donation. Among the 17 non-brain-dead patients, the average BIS values at admission and after rewarming were 39 (0-65) and 59 (22-82), respectively. Two patients had on admission a BIS value equal to zero and evolved to a poor prognostic (CPC 4) and died after care limitations. BIS values were significantly different between patients who developed brain death and those who did not. In both groups, no differences were observed between the AUCs of ROC curves for BIS values under MTH and after rewarming (respectively 0.86 vs 0.83, NS).

CONCLUSIONS

Initial values of BIS could be used as an assessment tool for early detection of brain-death in refractory cardiac arrest patients treated by mild therapeutic hypothermia and E-CPR.