Brain death determination in patients with veno-arterial extracorporeal membrane oxygenation: A systematic study to address the Harlequin syndrome

PURPOSE

The Harlequin syndrome may occur in patients treated with venoarterial extracorporal membrane oxygenation (VA-ECMO), in whom blood from the left ventricle and the ECMO system supply different parts of the body with different paCO2-levels. The purpose of this study was to compare two variants of paCO2-analysis to account for the Harlequin syndrome during apnea testing (AT) in brain death (BD) determination.

MATERIALS AND METHODS

Twenty-seven patients (median age 48 years, 26-76 years; male n = 19) with VA-ECMO treatment were included who underwent BD determination. In variant 1, simultaneous arterial blood gas (ABG) samples were drawn from the right and the left radial artery. In variant 2, simultaneous ABG samples were drawn from the right radial artery and the postoxygenator ECMO circuit. Differences in paCO2-levels were analysed for both variants.

RESULTS

At the start of AT, median paCO2-difference between right and left radial artery (variant 1) was 0.90 mmHg (95%-confidence intervall [CI]: 0.7-1.3 mmHg). Median paCO2-difference between right radial artery and postoxygenator ECMO circuit (variant 2) was 3.3 mmHg (95%-CI: 1.5-6.0 mmHg) and thereby significantly higher compared to variant 1 (p = 0.001). At the end of AT, paCO2-difference according to variant 1 remained unchanged with 1.1 mmHg (95%-CI: 0.9-1.8 mmHg). In contrast, paCO2-difference according to variant 2 increased to 9.9 mmHg (95%-CI: 3.5-19.2 mmHg; p = 0.002).

CONCLUSIONS

Simultaneous paCO2-analysis from right and left distal arterial lines is the method of choice to reduce the risk of adverse effects (e.g. severe respiratory acidosis) while performing AT in VA-ECMO patients during BD determination.

The use of quantitative pupillometry in brain death determination: preliminary findings

PURPOSE

Quantitative pupillometry (QP) has been increasingly applied in neurocritical care as an easy-to-use and reliable technique for evaluating the pupillary light reflex (PLR). Here, we report our preliminary findings on using QP for clinical brain death (BD) determination.

MATERIALS

This retrospective study included 17 patients ≥ 18 years (mean age, 57.3 years; standard deviation, 15.8 years) with confirmed BD, as defined by German Guidelines for the determination of BD. The PLR was tested using the NPi®-200 Pupillometer (Neuroptics, Laguna Hill, USA), a handheld infrared device automatically tracking and analyzing pupil dynamics over 3 s. In addition, pupil diameter and neurological pupil index (NPi) were also evaluated.

RESULTS

Intracerebral bleeding, subarachnoid hemorrhage, and hypoxic encephalopathy were the most prevalent causes of BD. In all patients, the NPi was 0 for both eyes, indicating the cessation of mid-brain function. The mean diameter was 4.9 mm (± 1.3) for the right pupil and 5.2 mm (±1.2) for the left pupil.

CONCLUSIONS

QP is a valuable tool for the BD certification process to assess the loss of PLR due to the cessation of brain stem function. Furthermore, implementing QP before the withdrawal of life-sustaining therapy in brain-injured patients may reduce the rate of missed organ donation opportunities. Further studies are warranted to substantiate the feasibility and potential of this technique in treating patients and identify suitable candidates for this technique during the BD certification process.

Effect of Hypertonic Saline Solution on the Ventilatory Mechanics of Lungs Donated After Brain Death

INTRODUCTION

Brain death (BD) compromises the viability of the lung for donation. Hypertonic saline solution (HSS) induces rapid intravascular volume expansion and immunomodulatory action. We investigated its role in ventilatory mechanics (VMs) and in the inflammatory activity of the lungs of rats subjected to BD.

METHODS

Wistar rats were divided into four groups: control, n = 10: intact rats subjected to extraction of the heart-lung block; BD, n = 8 (BD): rats treated with isotonic saline solution (4 mL/kg) immediately after BD; hypertonic saline 0 h, n = 9 (Hip.0'): rats treated with HSS (4 mL/kg) immediately after BD; and hypertonic saline 1 h, n = 9 (Hip.60'), rats treated with HSS (4 mL/kg) 60 min after BD. The hemodynamic characteristics, gas exchange, VMs, inflammatory mediators, and histopathological evaluation of the lung were evaluated over 240 min of BD.

RESULTS

In VMs, we observed increased airway resistance, tissue resistance, tissue elastance, and respiratory system compliance in the BD group (P < 0.037), while the treated groups showed no impairment over time (P > 0.05). In the histological analysis, the BD group showed a greater area of perivascular edema and a higher neutrophil count than the control group and the Hip.60' group (P < 0.05).

CONCLUSIONS

Treatment with HSS was effective in preventing changes in the elastic and resistive pulmonary components, keeping them at baseline levels. Late treatment reduced perivascular and neutrophilic edema in lung tissue.

A Recruitment Maneuver After Apnea Testing Improves Oxygenation and Reduces Atelectasis in Organ Donors After Brain Death

BACKGROUND

Hypoxemia is the main modifiable factor preventing lungs from being transplanted from organ donors after brain death. One major contributor to impaired oxygenation in patients with brain injury is atelectasis. Apnea testing, an integral component of brain death declaration, promotes atelectasis and can worsen hypoxemia. In this study, we tested whether performing a recruitment maneuver (RM) after apnea testing could mitigate hypoxemia and atelectasis.

METHODS

During the study period, an RM (positive end-expiratory pressure of 15 cm H2O for 15 s then 30 cm H2O for 30 s) was performed immediately after apnea testing. We measured partial pressure of oxygen, arterial (PaO2) before and after RM. The primary outcomes were oxygenation (PaO2 to fraction of inspired oxygen [FiO2] ratio) and the severity of radiographic atelectasis (proportion of lung without aeration on computed tomography scans after brain death, quantified using an image analysis algorithm) in those who became organ donors. Outcomes in RM patients were compared with control patients undergoing apnea testing without RM in the previous 2 years.

RESULTS

Recruitment maneuver was performed in 54 patients after apnea testing, with a median immediate increase in PaO2 of 63 mm Hg (interquartile range 0-109, p = 0.07). Eighteen RM cases resulted in hypotension, but none were life-threatening. Of this cohort, 37 patients became organ donors, compared with 37 donors who had apnea testing without RM. The PaO2:FiO2 ratio was higher in the RM group (355 ± 129 vs. 288 ± 127, p = 0.03), and fewer had hypoxemia (PaO2:FiO2 ratio < 300 mm Hg, 22% vs. 57%; p = 0.04) at the start of donor management. The RM group showed less radiographic atelectasis (median 6% vs. 13%, p = 0.045). Although there was no difference in lungs transplanted (35% vs. 24%, p = 0.44), both better oxygenation and less atelectasis were associated with a higher likelihood of lungs being transplanted.

CONCLUSIONS

Recruitment maneuver after apnea testing reduces hypoxemia and atelectasis in organ donors after brain death. This effect may translate into more lungs being transplanted.

Neurologic Complications in Critically Ill Patients with Toxic Alcohol Poisoning: A Multicenter Population-Based Cohort Study

BACKGROUND

Toxic alcohol poisoning is regularly encountered in emergency departments and intensive care units (ICUs). Most patients present with an altered level of consciousness, but the subsequent course and spectrum of neurologic complications and outcomes is highly variable.

METHODS

We performed a population-based, multicenter retrospective cohort study of critically ill patients with toxic alcohol poisoning admitted to ICUs in Alberta, Canada, between 2007 and 2019 to describe neurologic sequelae, including seizures, coma, neuroimaging abnormalities, persistent cognitive or visual impairment, and mortality. Multivariate analysis was performed to identify predictors of poor outcome.

RESULTS

We identified 104 patients, including 55 (53%) with methanol ingestion, 36 (35%) with ethylene glycol ingestion, and 13 (13%) with isopropanol ingestion. In patients who underwent neuroimaging, abnormalities were detected in 9 of 24 (38%) with methanol toxicity, 5 of 20 (25%) with ethylene glycol toxicity, and 0 of 10 with isopropanol toxicity (p = 0.07). Basal ganglia were commonly involved with both methanol and ethylene glycol poisoning, but prominent subcortical involvement and restricted diffusion were observed only with methanol poisoning. The composite of death, persistent cognitive impairment, or visual loss occurred in 13 (24%) patients with methanol poisoning, compared with one (3%) with ethylene glycol poisoning and none with isopropanol poisoning (p = 0.006). Among patients with methanol toxicity, greater elevation of the anion gap and lower Glasgow Coma Scale score were independent predictors of poor outcome. No patient with an anion gap ≥ 28 at presentation had a favorable recovery. Progression to death by neurologic criteria occurred in 3 of 55 (5%) patients with methanol poisoning and in none with other toxic alcohols.

CONCLUSIONS

Methanol overdose is the most common form of toxic alcohol poisoning to result in ICU admission. Poor neurologic outcomes may occur especially with methanol poisoning, with more than one in five patients dying or having persistent cognitive or visual impairment. A wide anion gap independently predicts poor outcome, emphasizing the importance of expeditious recognition and treatment.

Death as the extinction of the source of value: the constructivist theory of death as an irreversible loss of moral status

In 2017, Michael Nair-Collins formulated his Transitivity Argument which claimed that brain-dead patients are alive according to a concept that defines death in terms of the loss of moral status. This article challenges Nair-Collins' view in three steps. First, I elaborate on the concept of moral status, claiming that to understand this notion appropriately, one must grasp the distinction between direct and indirect duties. Second, I argue that his understanding of moral status implicit in the Transitivity Argument is faulty since it is not based on a distinction between direct and indirect duties. Third, I show how this flaw in Nair-Collins' argument is grounded in the more general problems between preference utilitarianism and desire fulfillment theory. Finally, I present the constructivist theory of moral status and the associated moral concept of death and explain how this concept challenges the Transitivity Argument. According to my view, brain death constitutes a valid criterion of death since brain death is incompatible with the preserved capacity to have affective attitudes and to value anything.

Medical students' knowledge and attitude toward brain death and the influence of medical education: a cross-sectional study

BACKGROUND

The medical students' knowledge and attitude toward brain death has not been investigated in China. The aims of this study were to assess the knowledge and attitude toward brain death among medical students in China and assess the influence of medical education on the knowledge and attitude.

METHODS

An online questionnaire consisting of 17 questions was developed and completed by undergraduates majoring in clinical medicine in China Medical University. The students' demographic data, knowledge and attitude toward brain death were collected and analyzed.

RESULTS

A total of 1075 medical students participated in the survey, and 1051 of them completed the valid questionnaire. The exploratory factor analysis grouped the 17 items into four dimensions, which explained 63.5% of the total variance. These dimensions were named as knowledge (5 items), attitude (5 items), concern (3 items) and education needs (4 items) respectively. The global Cronbach α of the questionnaire was 0.845 and the Cronbach α of the four dimensions ranged from 0.756 to 0.866. The mean dimension scores of knowledge, attitude, concern and education needs was 3.67 ± 0.89, 3.67 ± 0.87, 3.10 ± 1.03 and 4.12 ± 0.72 respectively. The clinical students had a better knowledge than the preclinical students (P < 0.001). The clinical students had a more favorable attitude in stopping the treatment for a brain-dead family member and using the organs and/or tissues of brain-dead patients for transplantation (P < 0.001). The clinical students showed more concerns than the preclinical students (P < 0.001). There was no significant difference in the education needs between the clinical and pre-clinical students.

CONCLUSIONS

Most medical students in China had insufficient knowledge about brain death. Although their knowledge of brain death increased with their university degree, their attitude toward organ donation after brain death did not evolve accordingly. Their concerns about brain death increased with seniority. Most students had great education needs about brain death.

Association of donor hepatectomy time with liver transplantation outcomes: A multicenter retrospective study

BACKGROUND

Prolonged donor hepatectomy time may be implicated in early and late complications of liver transplantation.

AIM

To evaluate the impact of donor hepatectomy time on outcomes of liver transplant recipients, mainly early allograft dysfunction.

METHODS

This multicenter retrospective study included brain-dead donors and adult liver graft recipients. Donor-recipient matching was obtained through a crossover list. Clinical and laboratory data were recorded for both donors and recipients. Donor hepatectomy, cold ischemia, and warm ischemia times were recorded. Primary outcome was early allograft dysfunction. Secondary outcomes included need for retransplantation, length of intensive care unit and hospital stay, and patient and graft survival at 12 months.

RESULTS

From January 2019 to December 2021, a total of 243 patients underwent a liver transplant from a brain-dead donor. Of these, 57 (25%) developed early allograft dysfunction. The median donor hepatectomy time was 29 (23-40) min. Patients with early allograft dysfunction had a median hepatectomy time of 25 (22-38) min, whereas those without it had a median time of 30 (24-40) min (P = 0.126).

CONCLUSION

Donor hepatectomy time was not associated with early allograft dysfunction, graft survival, or patient survival following liver transplantation.

Isolation and primary culture of human abdominal aorta smooth muscle cells from brain-dead donors: an experimental model for vascular diseases

Primary cell cultures are essential tools for elucidating the physiopathological mechanisms of the cardiovascular system. Therefore, a primary culture growth protocol of cardiovascular smooth muscle cells (VSMCs) obtained from human abdominal aortas was standardized. Ten abdominal aorta samples were obtained from patients diagnosed with brain death who were organ and tissue donors with family consent. After surgical ablation to capture the aorta, the aortic tissue was removed, immersed in a Custodiol® solution, and kept between 2 and 8 °C. In the laboratory, in a sterile environment, the tissue was fragmented and incubated in culture plates containing an enriched culture medium (DMEM/G/10% fetal bovine serum, L-glutamine, antibiotics and antifungals) and kept in an oven at 37 °C and 5% CO2. The aorta was removed after 24 h of incubation, and the culture medium was changed every six days for twenty days. Cell growth was confirmed through morphological analysis using an inverted optical microscope (Nikon®) and immunofluorescence for smooth muscle alpha-actin and nuclei. The development of the VSMCs was observed, and from the twelfth day, differentiation, long cytoplasmic projections, and adjacent cell connections occurred. On the twentieth day, the morphology of the VSMCs was confirmed by actin fiber immunofluorescence, which is a typical characteristic of VSMCs. The standardization allowed VSMC growth and the replicability of the in vitro test, providing a protocol that mimics natural physiological environments for a better understanding of the cardiovascular system. Its use is intended for investigation, tissue bioengineering, and pharmacological treatments.

Similarities in the Electrographic Patterns of Delayed Cerebral Infarction and Brain Death After Aneurysmal and Traumatic Subarachnoid Hemorrhage

While subarachnoid hemorrhage is the second most common hemorrhagic stroke in epidemiologic studies, the recent DISCHARGE-1 trial has shown that in reality, three-quarters of focal brain damage after subarachnoid hemorrhage is ischemic. Two-fifths of these ischemic infarctions occur early and three-fifths are delayed. The vast majority are cortical infarcts whose pathomorphology corresponds to anemic infarcts. Therefore, we propose in this review that subarachnoid hemorrhage as an ischemic-hemorrhagic stroke is rather a third, separate entity in addition to purely ischemic or hemorrhagic strokes. Cumulative focal brain damage, determined by neuroimaging after the first 2 weeks, is the strongest known predictor of patient outcome half a year after the initial hemorrhage. Because of the unique ability to implant neuromonitoring probes at the brain surface before stroke onset and to perform longitudinal MRI scans before and after stroke, delayed cerebral ischemia is currently the stroke variant in humans whose pathophysiological details are by far the best characterized. Optoelectrodes located directly over newly developing delayed infarcts have shown that, as mechanistic correlates of infarct development, spreading depolarizations trigger (1) spreading ischemia, (2) severe hypoxia, (3) persistent activity depression, and (4) transition from clustered spreading depolarizations to a negative ultraslow potential. Furthermore, traumatic brain injury and subarachnoid hemorrhage are the second and third most common etiologies of brain death during continued systemic circulation. Here, we use examples to illustrate that although the pathophysiological cascades associated with brain death are global, they closely resemble the local cascades associated with the development of delayed cerebral infarcts.

Simple approach to quantify hypoxic-ischemic brain injury severity from computed tomography imaging files after cardiac arrest

BACKGROUND

Grey-white ratio (GWR) can estimate severity of cytotoxic cerebral edema secondary to hypoxic-ischemic brain injury after cardiac arrest and predict progression to death by neurologic criteria (DNC). Current approaches to calculating GWR are not standardized and have variable interrater reliability. We tested if measures of variance of brain density on early computed tomographic (CT) imaging after cardiac arrest could predict DNC.

METHODS

We performed a retrospective cohort study, identifying post-arrest patients treated between 2011 and 2020 at our single center. We extracted demographic data from our registry and Digital Imaging and Communication in Medicine (DICOM) files for each patient's first brain CT. We analyzed slices 15-20 of each DICOM, corresponding to the level of the basal ganglia while accommodating differences in patient anatomy. We extracted pixel arrays and converted the radiodensities to Hounsfield units (HU). To focus on brain tissue densities, we excluded HU > 60 and < 10. We calculated the variance of each patient's HU distribution and the difference between the means of a two-group Gaussian finite mixture model. We compared these novel metrics to existing measures of cerebral edema, then randomly divided our data into 80% training and 20% test sets and used logistic regression to predict DNC.

RESULTS

Of 1,133 included subjects, 457 (40%) were female, mean (standard deviation) age was 58 (16) years, and 115 (10%) progressed to DNC. CTs were obtained a median [interquartile range] of 4.2 [2.8-5.7] hours post-arrest. Our novel measures correlated weakly with GWR. HU variance, but not difference between mixture model means, differed significantly between subjects with and without sulcal or cistern effacement. GWR outperformed our novel measures in predicting progression to DNC with an area under the receiver operating characteristic curve (AUC) of 0.82, compared to HU variance (AUC = 0.73) and the difference between mixture model means (AUC = 0.56).

CONCLUSION

There are differences in the distribution of HU on post-arrest CT in patients with qualitative measures of cerebral edema. Current methods to quantify cerebral edema outperform simple measures of attenuation variance on early brain CT. Further analyses could investigate if these measures of variance, or other distributional characteristics of brain density, have improved predictive performance on brain CTs obtained later in the clinical course or derived from discrete regions of anatomical interest.

Male versus female inflammatory response after brain death model followed by ex vivo lung perfusion

BACKGROUND

Ex vivo lung perfusion (EVLP) is a useful tool for assessing lung grafts quality before transplantation. Studies indicate that donor sex is as an important factor for transplant outcome, as females present higher inflammatory response to brain death (BD) than males. Here, we investigated sex differences in the lungs of rats subjected to BD followed by EVLP.

METHODS

Male and female Wistar rats were subjected to BD, and as controls sham animals. Arterial blood was sampled for gas analysis. Heart-lung blocks were kept in cold storage (1 h) and normothermic EVLP carried out (4 h), meanwhile ventilation parameters were recorded. Perfusate was sampled for gas analysis and IL-1β levels. Leukocyte infiltration, myeloperoxidase presence, IL-1β gene expression, and long-term release in lung culture (explant) were evaluated.

RESULTS

Brain dead females presented a low lung function after BD, compared to BD-males; however, at the end of the EVLP period oxygenation capacity decreased in all BD groups. Overall, ventilation parameters were maintained in all groups. After EVLP lung infiltrate was higher in brain dead females, with higher neutrophil content, and accompanied by high IL-1β levels, with increased gene expression and concentration in the culture medium (explant) 24 h after EVLP. Female rats presented higher lung inflammation after BD than male rats. Despite maintaining lung function and ventilation mechanics parameters for 4 h, EVLP was not able to alter this profile.

CONCLUSION

In this context, further studies should focus on therapeutic measures to control inflammation in donor or during EVLP to increase lung quality.

What determinants impact deceased organ donation consent in the adult intensive care unit? An integrative review exploring the perspectives of staff and families

BACKGROUND

Deceased organ donation saves lives. Donation processes in New Zealand operate under an opt-in system, which requires consent from families of patients diagnosed with brain death or circulatory death while in the intensivecare unit. The donation demand and supply mismatch is a global phenomenon.

OBJECTIVES

The objective of this study was to understand the determinants of deceased organ donation decisions in the adult intensive care setting from the perspectives of staff and families.

METHODS

An integrative review based on Whittemore and Knafl's approach searched literature through databases CINAHL Plus, SCOPUS, Proquest Medline Ovid, and manual ancestry searches. Inclusion/exclusion criteria screened for pertinent literature, which were reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Selected studies were appraised using a generic scoring tool, and data were systematically extracted and coded onto spreadsheets using inductive, thematic analysis.

RESULTS

A total of 21 studies (12 qualitative, seven quantitative, two mixed methods) were included. Publication dates ranged from 1993 to 2021 from multiple countries (18 opt-in, three opt-out systems). Four overarching themes pertaining to families and staff were generated. Important knowledge related to families' knowledge deficits around brain death, the purpose of ventilation, donation procedures, patients' wishes, and staffs' lack of training. Challenging communication highlighted miscommunications due to language choices and interrupted continuity of care during staff-family interactions. Internal determinants explored the cultural, spiritual, and emotional perspectives of families, while staff faced a sense of burden and conflicting values in delivering care between donors and recipients. External determinants related to the clinical environment impacting on grieving families, while for the staff, it explained concerns around resources and organisational processes.

CONCLUSIONS

Factors underpinning deceased organ donation are multifaceted and complex. Staff actions and families' decisions are inextricably intertwined. Modifiable factors include a lack of formal training and communicational skills and environmental limitations of an intensive care setting.

Facilitators and barriers in the donor family interview process from the perspective of hospital staff: a cross-sectional study

Background

Obtaining consent from potential donor families is a challenging step in the donation process and is influenced by various factors.

Methods

In this cross-sectional study, we utilized a questionnaire containing 14 questions about facilitators and barriers in the family interview process. The questionnaire was distributed in March 2023 to intensive care unit (ICU) nurses who had experience with donor family interviews. We collected the opinions of these respondents on hospital performance and drew comparisons between the studied hospitals.

Results

A total of 60 participating ICU nurses provided mean scores for hospital performance in family interviews of 2.60±0.84 for type I hospitals (those providing neurosurgery and trauma care) and 2.035±0.890 for type II hospitals (those without neurosurgery and trauma services; P=0.04). The mean scores for public and private hospitals were 1.86±0.86 and 2.59±0.85, respectively (P=0.008). Based on the findings, the most important facilitators were the availability of organ donation staff and access to a professional team for family discussions. Conversely, poor physician communication skills and limited communication capabilities among medical staff were identified as significant barriers. Implementation of a professional team for family interviews was found to be more critical for type II hospitals. Poor physician communication skills were a significant concern in public hospitals, while families' lack of awareness of patient prognosis emerged as a key barrier in private hospitals.

Conclusions

This study highlights numerous facilitators and barriers that vary across hospitals. Addressing these issues individually and developing tailored plans to enhance hospital performance in interviewing donor families is essential.

Retrospective Analysis of Patients Diagnosed with Brain Death in Our Hospital in the Last 15 Years

Objectives

Retrospective analysis of cases diagnosed with brain death in our hospital in the last 15 years.

Methods

The files and computer records of the cases diagnosed with brain death in the intensive care units of our hospital between January 2008 and January 2023 were evaluated retrospectively. The demographic data of the cases, the primary disease leading to brain death, the complementary tests used in the diagnosis of brain death, the day on which brain death was diagnosed in the intensive care unit, and the donor status were examined.

Results

A total of 228 cases diagnosed as brain death were detected. Seven patients with missing data were excluded from the study. 61.99% of the cases were male, 38.01% were female, 14.02% were under 18 years old, 68.34% were between 18 and 65 years old, 17.64% were over 65 years old. Brain death was diagnosed in 69.69% of the patients admitted to the intensive care unit in the first 7 days, 22.17% in 7-14 days, and 8.14% after 14 days. The primary disease causing brain death was found to be 47% hemorrhagic cerebral injury, 21% traumatic hemorrhagic injury, 18% ischemic cerebral injury, and 14% hypoxic cerebral injury. No ancillary testing was used in 38% of the cases. Carotid doppler ultrasound was used in 36%, computed tomography angiography was used in 22%, and transcranialdoppler was used in 4%. Families agreed to be organ transplant donors in 28.95% of the cases. 71.05% family members refused to be organ transplant donors.

Conclusion

The number of organ donations and the diagnosis of brain death has decreased rapidly with the covid-19 pandemic. In order to increase organ donation, we think that the necessary education should be given at an early age to increase organ donation awareness and social awareness.

Alterations in neuroendocrine axes in brain-dead patients

PURPOSE

To identify changes in anterior pituitary gland hormone levels in brain-dead patients and alterations in free triiodothyronine (fT3), free thyroxine, cortisol, testosterone, and estradiol levels.

METHODS

Ten postmenopausal women and 22 men with brain death (BD) were included. The first blood sample for determination of hormones (pre-BD) was collected when the clinician observed the first signs of BD. The second blood sample (BD day) was drawn after BD certification.

RESULTS

Female patients exhibited lower follicle-stimulating hormone and prolactin levels pre-BD and luteinizing hormone, follicle-stimulating hormone, and prolactin levels on BD day than the age-matched controls. Male patients' sex hormone levels were similar to those of the age-matched controls, except for testosterone levels, which were low in both consecutive measurements. All gonadotropins and prolactin levels were above the tests' lower detection limits (LDLs), except for one male patient with gonadotropin levels below the LDLs of the tests. Estradiol levels in both sexes ranged from normal to elevated. FT3 levels were significantly decreased in the two measurements. Thyroid-stimulating hormone (TSH) levels were low in eight patients and all low TSH levels were above the test's LDL. The remaining patients had normal or elevated TSH levels. The median adrenocorticotropic hormone (ACTH) and cortisol levels were within normal limits. All cortisol and ACTH levels were above the tests' LDLs, except for one patient with ACTH levels below the LDL in both measurements.

CONCLUSION

This study supports the hypothesis that the anterior pituitary gland continues to function in the brain-dead state.

[Diagnosis of brain death in Germany-Implementation of the guidelines of the German Medical Association]

BACKGROUND

The 4th update of the guidelines of the German Medical Association on the diagnosis of irreversible loss of brain function (brain death, BD) has introduced important new regulations regarding the required qualification of the examiners, approved procedures for ancillary testing, and a clarification regarding the sequencing of diagnostic steps.

OBJECTIVE

Investigation of the implementation and practical effects on the diagnosis of brain death.

METHOD

Descriptive evaluation of the routine documentation of the German Organ Procurement Organization, comparing the periods July 2011-June 2015 (3rd update) and July 2015-June 2019 (4th update).

RESULTS

Patient numbers decreased from 6100 to 5403. The largest decrease affected hospitals without neurosurgery. Children were not affected. With the 4th update, clinical diagnostics were increasingly performed during on-call hours by external neurologists. Of the patients 83.8% now received ancillary tests compared to 80.1% previously. Computed tomography angiography (CTA), first introduced in the 4th update, was applied in 23.2% and established complete loss of cerebral circulation in 89.4%. The time between first documentation of the clinical signs of BD and certification of BD increased from 7.0 ± 12.7 h to 8.2 ± 14.2 h. The diagnosis was slightly less frequent with 95.3% compared to 96.6%.

CONCLUSION

The updated standards were implemented in accordance with the guidelines. The demand for external consulting neurologists and neurosurgeons as well as the time required for BD assessment have increased. Negative effects on pediatric BD diagnostics were not apparent. CTA is widely and successfully used in adults as a new ancillary diagnostic procedure.

[Prospective investigation of extracranial duplex sonography for the detection of cerebral circulatory arrest in patients with irreversible loss of brain function]

BACKGROUND

A broader distribution of bedside color-coded duplex sonography (CCD) for detection of cerebral circulatory arrest (CCA) would be important to improve its use in the diagnosis of irreversible loss of brain function (ILBF-Dx).

QUESTION

Is extracranial compared to the commonly applied transcranial CCD of the brain-supplying vessels (ECCD vs. TCCD) equivalent for the detection of CCA in ILBF-Dx regarding specificity and sensitivity?

MATERIAL AND METHODS

Study period January 2019-June 2022, screening of 136 and inclusion of 114 patients with severe brain lesions > 24 h after onset of fixed and dilated pupils, apnea and completed ILBF-Dx. Exclusion of patients without brainstem areflexia and guideline-conform applicability of CCD. Complementary ECCD (and TCCD, if other method used for irreversibility detection).

RESULTS

Detection of ILBF (ILBF+) in 86.8% (99/114), no ILBF (ILBF-) in 13.2% (15/114). ECCD was fully feasible in all patients; findings matching CCA were found in 94/99 ILBF+ cases (ECCD+) and not in 5 patients (ECCD-). All 15 patients with ILBF- showed ECCD- findings. Thus, the specificity of ECCD was 1.0, and the sensitivity was 0.949. TCCD showed CCA in 56 patients (TCCD+), and ECCD+ was also found in all of them. An inconclusive result of TCCD in ILBF+ was found in 38 cases, with parallel ECCD+ in all of these patients. In 20 cases, TCCD did not show CCA (TCCD-), these also showed ECCD-. Of these patients 15 were ILBF- and 5 were ILBF+.

DISCUSSION

TCCD was not completely feasible or inconclusive in one third of the cases, whereas ECCD was always feasible. ECCD showed high validity with respect to the detection of CCA. Therefore, the possibility of using ECCD alone to detect CCA in ILBF-Dx should be discussed.

Identification of patients at high risk for brain death using an automated digital screening tool: a prospective diagnostic accuracy study

BACKGROUND

An automated digital screening tool (DETECT) has been developed to aid in the early identification of patients who are at risk of developing brain death during critical care.

METHODS

This prospective diagnostic accuracy study included consecutive patients ≥ 18 years admitted to neurocritical care for primary or secondary acute brain injury. The DETECT screening tool searched routinely monitored patient data in the electronic medical records every 12 h for a combination of coma and absence of bilateral pupillary light reflexes. In parallel, daily neurological assessment was performed by expert neurointensivists in all patients blinded to the index test results. The primary target condition was the eventual diagnosis of brain death. Estimates of diagnostic accuracy along with their 95%-confidence intervals were calculated to assess the screening performance of DETECT.

RESULTS

During the 12-month study period, 414 patients underwent neurological assessment, with 8 (1.9%) confirmed cases of brain death. DETECT identified 54 positive patients and sent 281 notifications including 227 repeat notifications. The screening tool had a sensitivity of 100% (95% CI 63.1-100%) in identifying patients who eventually developed brain death, with no false negatives. The mean time from notification to confirmed diagnosis of brain death was 3.6 ± 3.2 days. Specificity was 88.7% (95% CI 85.2-91.6%), with 46 false positives. The overall accuracy of DETECT for confirmed brain death was 88.9% (95% CI 85.5-91.8%).

CONCLUSIONS

Our findings suggest that an automated digital screening tool that utilizes routinely monitored clinical data may aid in the early identification of patients at risk of developing brain death.

Development and validation of a novel score to predict brain death after out-of-hospital cardiac arrest

BACKGROUND AND OBJECTIVES

Brain death (BD) occurs in 9-24% of successfully resuscitated out-of-hospital cardiac arrests (OHCA). To predict BD after OHCA, we developed a novel brain death risk (BDR) score.

METHODS

We identified independent predictors of BD after OHCA in a retrospective, single academic center cohort between 2011 and 2021. The BDR score ranges from 0 to 7 points and includes: non-shockable rhythm (1 point), drug overdose as etiology of arrest (1 point), evidence of grey-white differentiation loss or sulcal effacement on head computed tomography (CT) radiology report within 24 hours of arrest (2 points), Full-Outline-Of-UnResponsiveness (FOUR) score of 0 (2 points), FOUR score 1-5 (1 point), and age <45 years (1 point). We internally validated the BDR score using k-fold cross validation (k = 8) and externally validated the score at an independent academic center. The main outcome was BD.

RESULTS

The development cohort included 362OHCA patients, of whom 18% (N = 58) experienced BD. Internal validation provided an area under the receiving operator characteristic curve (AUC) (95% CI) of 0.931 (0.905-0.957). In the validation cohort, 19.8% (N = 17) experienced BD. The AUC (95% CI) was 0.849 (0.765-0.933). In both cohorts, a BDR score >4 was the optimal cut off (sensitivity 0.903 and 0.882, specificity 0.830 and 0.652, in the development and validation cohorts respectively).

DISCUSSION

The BDR score identifies those at highest risk for BD after OHCA. Our data suggest that a BDR score >4 is the optimal cut off.

Intestinal microbiota dysbiosis and liver metabolomic changes during brain death

Background

Whether a causative link exists between brain death (BD) and intestinal microbiota dysbiosis is unclear, and the distortion in liver metabolism associated with BD requires further exploration.

Methods

A rat model of BD was constructed and sustained for 9 h (BD group, n=6). The sham group (n=6) underwent the same procedures, but the catheter was inserted into the epidural space without ballooning. Intestinal contents and portal vein plasma were collected for microbiota sequencing and microbial metabolite detection. Liver tissue was resected to investigate metabolic alterations, and the results were compared with those of a sham group.

Results

α-diversity indexes showed that BD did not alter bacterial diversity. Microbiota dysbiosis occurred after 9 h of BD. At the family level, Peptostreptococcaceae and Bacteroidaceae were both decreased in the BD group. At the genus level, Romboutsia, Bacteroides, Erysipelotrichaceae_UCG_004, Faecalibacterium, and Barnesiella were enriched in the sham group, whereas Ruminococcaceae_UCG_007, Lachnospiraceae_ND3007_group, and Papillibacter were enriched in the BD group. Short-chain fatty acids, bile acids, and 132 other microbial metabolites remained unchanged in both the intestinal contents and portal vein plasma of the BD group. BD caused alterations in 65 metabolites in the liver, of which, carbohydrates, amino acids, and organic acids accounted for 64.6%. Additionally, 80.0% of the differential metabolites were decreased in the BD group livers. Galactose metabolism was the most significant metabolic pathway in the BD group.

Conclusions

BD resulted in microbiota dysbiosis in rats; however, this dysbiosis did not alter microbial metabolites. Deterioration in liver metabolic function during extended periods of BD may reflect a continuous worsening in energy deficiency.

Perspectives of Medical Organizations, Organ Procurement Organizations, and Advocacy Organizations About Revising the Uniform Determination of Death Act (UDDA)

BACKGROUND

The Uniform Law Commission paused work of the Drafting Committee to Revise the Uniform Determination of Death Act (UDDA) in September 2023.

METHODS

Thematic review was performed of comments submitted to the Uniform Law Commission by medical organizations (MO), organ procurement organizations (OPO), and advocacy organizations (AO) from 1/1/2023 to 7/31/2023.

RESULTS

Of comments from 41 organizations (22 AO, 15 MO, 4 OPO), 34 (83%) supported UDDA revision (50% OPO, 33% MO recommended against revision). The most comments addressed modifications to "all functions of the entire brain, including the brainstem" (31; 95% AO, 75% OPO, 47% MO), followed by irreversible versus permanent (25; 77% AO, 50% OPO, 40% MO), accommodation of brain death/death by neurologic criteria (BD/DNC) objections (23; 100% OPO, 80% MO, 32% AO), consent for BD/DNC evaluation (18; 75% OPO, 47% MO, 36% AO), "accepted medical standards" (13; 36% AO, 33% MO, 0% OPO), notification before BD/DNC evaluation (14; 100% OPO, 53% MO, 9% AO), time to gather before discontinuation of organ support after BD/DNC determination (12; 60% MO, 25% OPO, 9% AO), and BD/DNC examiner credential requirements (2; 13% MO, 0% AO, 0% OPO). The predominant themes were that the revised UDDA should include the term "irreversible" and shouldn't (1) stipulate specific medical guidelines, (2) require notification before BD/DNC evaluation, or (3) require time to gather before discontinuation of organ support after BD/DNC determination. Views on other topics were mixed, but MO and OPO generally advocated for the revised UDDA to take a functional approach to BD/DNC, not require consent for BD/DNC evaluation, and not require opt-out accommodation of BD/DNC objections. Contrastingly, many AO and some MO with religious affiliations or a focus on advocacy favored the revised UDDA take an anatomic approach to BD/DNC or eliminate BD/DNC altogether, require consent for BD/DNC evaluation, and require opt-out accommodation of BD/DNC objections.

CONCLUSIONS

Most commenting organizations support UDDA revision, but perspectives on the approach vary, so the Drafting Committee could not formulate revisions that would be agreeable to all stakeholders.

Diagnostic Value of Computed Tomography Angiography in Confirmation of Brain Death

BACKGROUND

Accurate and on-time confirmation of brain death (BD) is necessary to prevent unnecessary treatment and allow for well-timed organ harvest for transplantation. Although the clinical criteria for BD are legally reliable in some countries, others might prefer complementary ancillary tests to assess the brain's electrical activity and/or blood circulation. The present study aims to define the sensitivity and specificity of computed tomography angiography using 4-, 7-, and 10-point tests compared with the clinical criteria and electroencephalographic findings in patients with BD.

METHODS

A total of 32 patients with a confirmed diagnosis of BD according to their clinical criteria (cases) and 18 patients with a Glasgow coma scale score of 3 and absent brain stem and papillary reflexes who had spontaneous respiration (controls) were included in the present study. All the patients had blood pressure >90 mm Hg, diuresis >100 mL/hour, and central venous pressure >6-8 mm Hg, and undergone computed tomography angiography (CTA). The 4-, 6-, and 10-point criteria were used to determine the opacity and lack of opacity of the brain vessels in the CTA evaluation scales for the diagnosis of BD.

RESULTS

The 2 groups were homogeneous in terms of age, gender distribution, and coma etiology. All 18 patients in the control group received a score of 0 in the 4-, 7-, and 10-point scores. In contrast, the average values for the 4-, 7-, and 10-point scores for the patients with confirmed BD were 3.75 ± 0.67, 6.4 ± 1.36, and 9.06 ± 2.2, respectively. Of the patients with BD, 28 (87.5%), 26 (81.25%), and 25 (78.12%) received the full score for the 4-point, 7-point, and 10-point tests. The sensitivity, specificity, and negative and positive predictive values for all 3 scores were 100%. Also, the sensitivity for the various cerebral vessels were as follows: internal cerebral vein, 100%; great cerebral vein, 96.9%; posterior 2, 90.6%, middle 4, 87.5%; basilar artery, 84.4%; and anterior 3, 84.4%. Finally, the specificity for the lack of opacification in all these vessels for the diagnosis of BD was 100%.

CONCLUSIONS

According to our findings, the CTA-based 4-point scoring system with 100% specificity can be used with the clinical examination findings to confirm BD.

The impact of clinical education on knowledge and attitudes towards brain death among Polish medical students - a cross-sectional study

BACKGROUND

Understanding brain death is essential for progress in organ transplantation; however, it remains a challenging ethical matter. In 2019, Poland revised its legislation on brain death to align with international standards. This study aimed to evaluate the knowledge and worldview concerning brain death among Polish medical students, categorised according to their stage of education.

METHODS

An online questionnaire was administered to 169 medical students from four Polish medical universities. The participants were divided into preclinical (n = 94) and clinical (n = 75) groups. The questionnaire consisted of two parts, with the first part comprising 13 questions focusing on knowledge about brain death and the process of its determination. The second part contained six questions related to the participants' worldview regarding brain death, particularly concerning organ transplantation.

RESULTS

The average score obtained by the respondents was 7.53 (± 2.35; min. 1, max. 13) in knowledge checking part of the developed questionnaire (maximal score:13). Students in the clinical stage of their education achieved significantly higher scores compared to preclinical students (mean 8.84; ± 1.89 vs mean 6.49; ± 2.15; p < 0.001). Significant correlations were found between the results of the knowledge part of the questionnaire and responses to worldview questions.

CONCLUSIONS

The stage of education influenced the knowledge of brain death among medical students, although the overall test scores were unsatisfactory. Higher test scores were associated with worldview responses indicating compliance with the current legislation in Poland and evidence-based medicine.

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.

"Hot nose" sign in brain death

Background

Brain death testing is a rigorous process in which meticulous examination is crucial. In certain cases, ancillary testing is required.

Case Description

A 30-year-old male presented to the emergency room after a motor vehicle accident and was found to have subarachnoid hemorrhage and subdural hematoma. The examination was notable for the absence of brainstem responses. A nuclear medicine brain scan was completed which showed carotid arterial activity up to the level of the skull base with no intracranial arterial activity above with a "hot nose" sign consistent with brain death.

Conclusion

The "hot nose" sign has been described in brain-dead patients and is postulated to occur due to increased flow to the nose through the external carotid artery.

Death pluralism: a proposal

The debate over the determination of death has been raging for more than fifty years. Since then, objections against the diagnosis of brain death from family members of those diagnosed as dead-have been increasing and are causing some countries to take novel steps to accommodate people's beliefs and preferences in the determination of death. This, coupled with criticism by some academics of the brain death criterion, raises some questions about the issues surrounding the determination of death. In this paper, we discuss some of the main approaches to death determination that have been theoretically proposed or currently put into practice and propose a new approach to death determination called "weak pluralism" as a reasonable ethical and political alternative to respect diversity in death determination.

Making a dead woman pregnant? A critique of the thought experiment of Anna Smajdor

In a thought-provoking article - or how she herself named it, 'a thought experiment' - the philosopher-medical ethicist Anna Smajdor analyzed in this journal the idea of whole-body gestational donation (WBGD) in brain-dead female patients, as an alternative means of gestation for prospective women who cannot or prefer not to become pregnant themselves. We have serious legal, economical, medical and ethical concerns about this proposal. First, consent for eight months of ICU treatment can never be assumed to be derived from consent for post-mortem organ donation; these two are of an incomparable and entirely different medical and ethical order. Moreover, the brain-dead woman is very likely to be medically unfit for high-tech surrogacy and the brain-dead state poses a high risk for deficient embryo/fetal development. Second, from a scarcity perspective, occupying an ICU bed for eight months appears to be unjust. The costs for eight months of ICU treatment are far too high compared to the costs of surrogacy for a living, selected, and healthy woman. Neither insurance companies nor prospective parents will want to pay these exceptionally high costs for a dead woman if a living surrogate mother can be hired for a considerably lower amount. Third, there is an increased risk for harm of the child to be in WBGD. And finally, WBGD risks violating the brain-dead woman's dignity and harming the interests of her loved ones. In short, there is simply no need for brain-dead women as surrogates.

Brain Death: Ethical and Legal Challenges

Although the fundamental principle behind the Uniform Determination of Death Act (UDDA), the equivalence of death by circulatory-respiratory and neurologic criteria, is accepted throughout the United States and much of the world, some families object to brain death/death by neurologic criteria. Clinicians struggle to address these objections. Some objections have been brought to court, particularly in the United States, leading to inconsistent outcomes and discussion about potential modifications to the UDDA to minimize ethical and legal controversies related to the determination of brain death/death by neurologic criteria.

The Moral Illicitness of Relying Solely on Neurological Criteria for the Determination of Death: A Catholic Response to "Brain Death"

This paper presents the biological, philosophical, and theological arguments against "brain death" or death determined strictly through neurological criteria. It is rooted in a realistic, Thomistic metaphysical and anthropological view of the human person and the objective reality of death. Part I of the paper reviews the medical evidence that the bodies of those declared brain death are alive and makes clear that the bodies of "brain dead" patients are not biologically analogous to severed body parts. Part II presents the philosophical and theological argument that it is impossible to be a live human being and not a person. Since then those declared brain dead are somatically alive, they are live human persons with the right to life and cannot be subject to the extraction of vital, unpaired organs, since this would violate the dead donor rule. Part III reviews why the Magisterium has not unconditionally approved the determination of death through neurological criteria, and why it would be within the competence of the Magisterium to preclude medical professionals from determining death strictly through neurological criteria. The paper argues that there should be a ban on all vital, unpaired organ donation from "brain dead" donors.

Why whole body gestational donation must be rejected: a response to Smajdor

Anna Smajdor's proposal of whole body gestational donation (WBGD) states that female patients diagnosed as brain-dead should be considered for use as gestational donors. In this response, Smajdor's proposal is rejected on four different accounts: (a) the debated acceptability of surrogacy despite women's autonomy, (b) the harm to dead women ́s interests, (c) the interests of the descendants, and (d) the symbolic value of the body and interests of relatives. The first part argues that WBGD rests on a particular conception of the instrumentalization of bodies that cannot be circumvented simply by the patient's consent and relinquished autonomy. The second part argues the importance of avoiding any harm to dead women's interests. The third part identifies the importance of the interest of the foetus in the light of Procreative-Beneficence principle that Smajdor overlooks. And finally, the fourth part considers the symbolic value of the human body and the interest of relatives. The main goal of this commentary is not to show that WBGD cannot be implemented; rather, it is to show that there are not any good arguments in favour of doing so.

Confirmatory digital subtraction angiography after clinical brain death/death by neurological criteria: impact on number of donors and organ transplants

Background

Demand for organs exceeds the number of transplants available, underscoring the need to optimize organ donation procedures. However, protocols for determining brain death (BD)/death by neurological criteria (DNC) vary considerably worldwide. In Denmark, digital subtraction angiography (DSA) is the only legally approved confirmatory test for diagnosing BD/DNC. We investigated the effect of the time delay caused by (repeat) confirmatory DSA on the number of organs donated by patients meeting clinical criteria for BD/DNC. We hypothesized that, first, patients investigated with ≥2 DSAs donate fewer organs than those investigated with a single DSA; second, radiological interpretation of DSA is subject to interrater variability; and third, residual intracranial circulation is inversely correlated with inotropic blood pressure support.

Methods

All DSAs performed over a 7-year period as part of BD/DNC protocols at Rigshospitalet, Copenhagen University Hospital, Denmark, were included. Clinical data were extracted from electronic health records. DSAs were reinterpreted by an independent neurinterventionist blinded to the original radiological reports.

Results

We identified 130 DSAs in 100 eligible patients. Patients with ≥2 DSAs (n = 20) donated fewer organs (1.7 +/- 1.6 SD) than patients undergoing a single DSA (n = 80, 2.6 +/- 1.7 organs, p = 0.03), and they became less often donors (n = 12, 60%) than patients with just 1 DSA (n = 65, 81.3%; p = 0.04). Interrater agreement of radiological DSA interpretation was 88.5% (Cohen's kappa = 0.76). Patients with self-maintained blood pressure had more often residual intracranial circulation (n = 13/26, 50%) than patients requiring inotropic support (n = 14/74, 18.9%; OR = 0.23, 95% CI [0.09-0.61]; p = 0.002).

Discussion

In potential donors who fulfill clinical BD/DNC criteria, delays caused by repetition of confirmatory DSA result in lost donors and organ transplants. Self-maintained blood pressure at the time of clinical BD/DNC increases the odds for residual intracranial circulation, creating diagnostic uncertainty because radiological DSA interpretation is not uniform. We suggest that avoiding unnecessary repetition of confirmatory investigations like DSA may result in more organs donated.

Frequent Preservation of Neurologic Function in Brain Death and Brainstem Death Entails False-Positive Misdiagnosis and Cerebral Perfusion

Some patients who have been diagnosed as "dead by neurologic criteria" continue to exhibit certain brain functions, most commonly, neuroendocrine functions. This preservation of neurologic function after the diagnosis of "brain death" or "brainstem death" is an ongoing source of controversy and concern in the medical, bioethics, and legal literatures. Most obviously, if some brain function persists, then it is not the case that all functions of the entire brain have ceased and hence, declaring such a patient to be "dead" would be a false positive, in any nation with so-called "whole brain death" laws. Furthermore, and perhaps more concerning, the preservation of any brain function necessarily entails the preservation of some amount of brain perfusion, thereby raising the concern as to whether additional areas of neural tissue may remain viable, including areas in the brainstem. These and other considerations cast significant doubt on the reliability of diagnosing either "brain death" or "brainstem death."

Analysis of rebound intracranial pressure occurring during rewarming after therapeutic hypothermia in traumatic brain injury patients

OBJECTIVE

To investigate the risk factors associated with rebound intracranial pressure (ICP), a phenomenon that occurs when brain swelling reprogresses rapidly during rewarming in patients who have undergone therapeutic hypothermia for traumatic brain injury (TBI).

METHODS

This study analyzed 42 patients who underwent therapeutic hypothermia among 172 patients with severe TBI admitted to a single regional trauma center between January 2017 and December 2020. Forty-two patients were classified into 34.5 °C (mild) and 33 °C (moderate) hypothermia groups according to the therapeutic hypothermia protocol for TBI. Rewarming was initiated post-hypothermia, wherein ICP was maintained at ≤ 20 mmHg and cerebral perfusion pressure was maintained at ≥ 50 mmHg for ≥ 24 h. In the rewarming protocol, the target core temperature was increased to 36.5 °C at 0.1 °C/h.

RESULTS

Of the 42 patients who underwent therapeutic hypothermia, 27 did not survive: 9 in the mild and 18 in the moderate hypothermia groups. The moderate hypothermia group had a significantly higher mortality rate than the mild hypothermia group (p = 0.013). Rebound ICP occurred in 9 of 25 patients: 2 in the mild and 7 in the moderate hypothermia groups. In the risk factor analysis of rebound ICP, only the degree of hypothermia was statistically significant, and rebound ICP was observed more frequently in the moderate than in the mild hypothermia group (p = 0.025).

CONCLUSIONS

In patients who underwent rewarming after therapeutic hypothermia, rebound ICP presented a higher risk at 33 °C than at 34.5 °C. Therefore, more careful rewarming is needed in patients receiving therapeutic hypothermia at 33 °C.

Organ donation by children in Australia, 2000-2019: impact of the 2009 National Reform Program. A population-based registry data study

OBJECTIVES

To assess the impact of the 2009 National Reform Program for organ donation in Australia on the number and characteristics of organ donors under 16 years of age.

DESIGN, SETTING, PARTICIPANTS

Retrospective observational time series study; analysis of Australia and New Zealand Organ Donation (ANZOD) registry data for all consented potential deceased organ donors under 16 years of age during 2000-2019, and of numbers of donors aged 16 years or more reported in ANZOD annual reports.

MAIN OUTCOME MEASURES

Difference between 2000-2008 (pre-reform) and 2009-2019 (reform period) in annual organ donor rates (donors per million population), by age group (under 16 years, 16 years or more), reported as incidence rate ratio (IRR).

SECONDARY OUTCOMES

Differences in child donor characteristics during 2000-2008 and 2009-2019.

RESULTS

During 2000-2019, 400 children under 16 years of age were consented potential deceased organ donors, of whom 374 were actual deceased donors (94%): 146 during 2000-2008, 228 during 2009-2019. The median annual rate was 3.3 (interquartile range [IQR], 3.0-4.3) actual donors per million population during 2000-2008 and 4.2 (IQR, 3.6-5.2) donors per million population during 2009-2019 (IRR, 1.15; 95% confidence interval [CI], 0.93-1.42). In contrast, the difference between the two periods was statistically significant for donors aged 16 years or more, rising from 11.7 (IQR, 11.2-11.8) to 19.9 (IQR, 18.3-24.4) actual donors per million population (IRR, 1.75; 95% CI, 1.66-1.85). The median age of actual organ donors under 16 was similar during 2000-2008 (11 years; IQR, 7-14 years) and 2009-2019 (10 years; IQR, 4-14 years), as was the proportion of donors in this age group under 10 kg (2000-2008: four of 146, 3%; 2009-2019: 14 of 228, 6%).

CONCLUSIONS

Despite its overall effect on organ donation rates, the National Reform Program was not effective in increasing the numbers of donors under 16 years of age. Relying on broad initiatives for adult donors may not be appropriate for achieving this aim.

Comparison of acute kidney injury following brain death between male and female rats

BACKGROUND

Clinical reports associate kidneys from female donors with worse prognostic in male recipients. Brain Death (BD) produces immunological and hemodynamic disorders that affect organ viability. Following BD, female rats are associated with increased renal inflammation interrelated with female sex hormone reduction. Here, the aim was to investigate the effects of sex on BD-induced Acute Kidney Injury (AKI) using an Isolated Perfused rat Kidney (IPK) model.

METHODS

Wistar rats, females, and males (8 weeks old), were maintained for 4h after BD. A left nephrectomy was performed and the kidney was preserved in a cold saline solution (30 min). IPK was performed under normothermic temperature (37°C) for 90 min using WME as perfusion solution. AKI was assessed by morphological analyses, staining of complement system components and inflammatory cell markers, perfusion flow, and creatinine clearance.

RESULTS

BD-male kidneys had decreased perfusion flow on IPK, a phenomenon that was not observed in the kidneys of BD-females (p < 0.0001). BD-male kidneys presented greater proximal (p = 0.0311) and distal tubule (p = 0.0029) necrosis. However, BD-female kidneys presented higher expression of eNOS (p = 0.0060) and greater upregulation of inflammatory mediators, iNOS (p = 0.0051), and Caspase-3 (p = 0.0099). In addition, both sexes had increased complement system formation (C5b-9) (p=0.0005), glomerular edema (p = 0.0003), and nNOS (p = 0.0051).

CONCLUSION

The present data revealed an important sex difference in renal perfusion in the IPK model, evidenced by a pronounced reduction in perfusate flow and low eNOS expression in the BD-male group. Nonetheless, the upregulation of genes related to the proinflammatory cascade suggests a progressive inflammatory process in BD-female kidneys.

Whole body gestational donation

Whole body gestational donation offers an alternative means of gestation for prospective parents who wish to have children but cannot, or prefer not to, gestate. It seems plausible that some people would be prepared to consider donating their whole bodies for gestational purposes just as some people donate parts of their bodies for organ donation. We already know that pregnancies can be successfully carried to term in brain-dead women. There is no obvious medical reason why initiating such pregnancies would not be possible. In this paper, I explore the ethics of whole-body gestational donation. I consider a number of potential counter-arguments, including the fact that such donations are not life-saving and that they may reify the female reproductive body. I suggest if we are happy to accept organ donation in general, the issues raised by whole-body gestational donation are differences of degree rather than substantive new concerns. In addition, I identify some intriguing possibilities, including the use of male bodies-perhaps thereby circumventing some potential feminist objections.

Suitability of electroencephalography in brain death determination: a monocentric, 10-year retrospective, observational investigation of 428 cases

BACKGROUND

We aimed to verify the usefulness of electroencephalographic (EEG) activity recording (that is mandatory according to the Italian law), in addition to two clinical evaluations spaced 6 h, among the procedures of brain death determination (BDD) in adult individuals.

METHODS

The study is a monocentric, retrospective analysis of all BDDs performed in the last 10 years at Policlinico Le Scotte in Siena (Italy).

RESULTS

Of the 428 cases revised (mean age 67.6 ± 15.03 years; range 24-92 years), 225 were males and 203 females. In total, 212 out of 428 patients (49.5%) were donors. None of the BDD procedures were interrupted due to the reappearance of EEG activity (neither for clinical reasons) at any sampling time, with the exception of one case that was considered a false negative at critical reinspection of the EEG. In 6/428 cases (1.4%), a cardiac arrest occurred during the 6 h between the first and second evaluation, thus missing the opportunity to take organs from these patients because the BDD procedure was not completed.

CONCLUSIONS

Once the initial clinical examination before convening the BDD Commission has ascertained the absence of brainstem reflexes and of spontaneous breathing, and these clinical findings are supported by a flat EEG recording, the repetition of a 30-min EEG twice over a 6 h period seems not to add additional useful information to clinical findings. Current data, if confirmed in other centers and possibly in prospective studies, may help to promote a scientific and bioethical debate in Italy, as well as in other countries where the EEG is still mandatory, for eventually updating the procedures of BDD.

Suitability of electroencephalography in brain death determination: a monocentric, 10-year retrospective, observational investigation of 428 cases

BACKGROUND

We aimed to verify the usefulness of electroencephalographic (EEG) activity recording (that is mandatory according to the Italian law), in addition to two clinical evaluations spaced 6 h, among the procedures of brain death determination (BDD) in adult individuals.

METHODS

The study is a monocentric, retrospective analysis of all BDDs performed in the last 10 years at Policlinico Le Scotte in Siena (Italy).

RESULTS

Of the 428 cases revised (mean age 67.6 ± 15.03 years; range 24-92 years), 225 were males and 203 females. In total, 212 out of 428 patients (49.5%) were donors. None of the BDD procedures were interrupted due to the reappearance of EEG activity (neither for clinical reasons) at any sampling time, with the exception of one case that was considered a false negative at critical reinspection of the EEG. In 6/428 cases (1.4%), a cardiac arrest occurred during the 6 h between the first and second evaluation, thus missing the opportunity to take organs from these patients because the BDD procedure was not completed.

CONCLUSIONS

Once the initial clinical examination before convening the BDD Commission has ascertained the absence of brainstem reflexes and of spontaneous breathing, and these clinical findings are supported by a flat EEG recording, the repetition of a 30-min EEG twice over a 6 h period seems not to add additional useful information to clinical findings. Current data, if confirmed in other centers and possibly in prospective studies, may help to promote a scientific and bioethical debate in Italy, as well as in other countries where the EEG is still mandatory, for eventually updating the procedures of BDD.

Alpha-1-Antitrypsin Protects Vascular Grafts of Brain-Dead Rats Against Ischemia/Reperfusion Injury

INTRODUCTION

Endothelial dysfunction is a potential side effect of brain death (BD). Ischemia/reperfusion (IR) injury during heart transplantation may lead to further endothelial damage. Protective effects of alpha-1-antitrypsin (AAT), a human neutrophil serine protease inhibitor, have been demonstrated against IR injury. We hypothesized that AAT protects brain-dead rats' vascular grafts from IR injury.

METHODS

Donor rats were subjected to BD by inflation of a subdural balloon. After 5.5 h, aortic rings were immediately mounted in organ baths (BD, n = 6 rats) or preserved in saline, supplemented either with vehicle (BD-IR, n = 8 rats) or AAT (BD-IR + AAT, n = 14 rats) for 24 h. During organ bath experiment, rings from both IR groups were exposed to hypochlorite to simulate warm reperfusion-associated endothelial injury. Endothelial function was measured ex vivo. Immunohistochemical staining for caspases was carried out and DNA-strand breaks were evaluated using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. Data are presented as median (interquartile range).

RESULTS

AAT improved IR-induced decreased maximum endothelium-dependent vasorelaxation to acetylcholine in the BD-IR + AAT aortas compared to the BD-IR group (BD: 83 (9-28) % versus BD-IR: 49 (39-60) % versus BD-IR + AAT: 64 (24-42) %, P < 0.05). Additionally, an increase in the rings' sensitivity to acetylcholine was noted after AAT (pD₂-value: BD-IR + AAT: 7.35 (7.06-7.89) versus BD-IR: 6.96 (6.65-7.21), P < 0.05). Caspase-3, -8, -9, and -12 immunoreactivity and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive cells were significantly decreased by AAT.

CONCLUSIONS

AAT alleviates endothelial dysfunction, prevents increased caspase-3, -8, -9, and -12 levels, and decreases apoptotic DNA breakage due to BD and IR injury. This suggests that AAT treatment may be therapeutically beneficial to reduce IR-induced vascular damage.

Variability across countries for brain death determination in adults

BACKGROUND

The guidelines of brain death determination vary across countries. Our aim was to compare diagnostic procedures of brain death determination in adults among five countries.

METHOD

Consecutive comatose patients who received brain death determination from June 2018 to June 2020 were included. The technical specifications, completion rates and positive rates of brain death determination according to criteria of different countries were compared. The accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of each ancillary test for the identification of brain death diagnosed according to different criteria were investigated.

RESULTS

One hundred and ninety nine patients were included in this study. One hundred and thirty one (65.8%) patients were diagnosed with brain death according to French criteria, 132 (66.3%) according to Chinese criteria, and 135 (67.7%) according to criteria of USA, UK and Germany. The sensitivity and PPV of electroencephalogram (92.2% - 92.3%) and somatosensory evoked potential (95.5% - 98.5%) were higher than transcranial Doppler (84.3% - 86.0%).

CONCLUSIONS

The criteria of brain death in China and France are comparatively stricter than in USA, UK and Germany. The discrepancy in brain death determination between clinical assessments and additional confirmation of ancillary tests is small.

Single institution experience with death by neurological criteria/brain death guideline adherence

OBJECTIVE

To determine the effect on adherence to an institutional death by neurological criteria/brain death (DNC/BD) policy of implementation of a standardized DNC/BD checklist in the electronic medical record (EMR).

METHODS

The retrospective study cohort included all patients admitted to our institution who were declared dead by neurologic criteria determined by ICD code (G93.82) between June 2015 and October 2019. Two investigators independently reviewed each case for adherence with institutional policy, and agreement was assessed using unweighted kappa statistics. Patient data and adherence to institutional policy before and after implementation of a standardized DNC/BD checklist were compared.

RESULTS

There were 66 patients identified by the initial search and 38 were included in the final analysis, with 19 cases in both the pre- and post- checklist periods. There were no significant differences in age, cause of DNC/BD, time to DNC/BD determination, potential toxic, metabolic, physiologic confounders, or use of ancillary testing. The pre-checklist period adherence was 47.4% (n = 9/19) versus 94.6% (n = 18/19; p = 0.001) in the post-checklist EMR DNC/BD period.

CONCLUSION

Implementation of a standardized EMR checklist substantially improved DNC/BD policy adherence in our institution.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence on the use of standardized EMR checklist to improve death by neurologic criteria/brain death policy adherence.

Is there any relationship between red blood cell distribution width and prognosis of brain death?

Background

Accumulating evidence has demonstrated that RDW (red blood cell distribution width) may independently predict clinically important outcomes in many populations. However, the role of RDW has not been elucidated in brain death. We conducted this study with the aim of evaluating the predictive value of RDW in brain death.

Methods

A retrospective study of seventy-seven of brain death cases during 36 months were evaluated at university hospitals, affiliated in Tehran, Iran. Demographical data include age, sex, BMI and cause of brain death, also laboratory results (red blood cell distribution, mean corpuscular volume, hemoglobin) collected by checklists from patient records. Having the three RDW measurements (days of hospital admission, day of brain death, and day of cardiac arrest) required.

Results

Time interval from hospital admission until brain death was 5.27±4.07. The mean age of brain death cases was 32.65±16.53. The mean RDW values on days of hospital admission, the day of brain death, and the day of cardiac arrest were 14.53±1.98, 15.12±1.93 and 15.18±2.07, respectively. Results of the repeated-measures ANOVA test reveal that RDW level was constantly higher in the traumatic patient group compared to the non-traumatic ones (P=0.008).

Conclusion

The frequency of brain death was high in patients with high RDW values. RDW might be a prognostic biomarker for brain death. More prospective studies with large sample size and long follow-up period should be carried out to determine the prognostic significance of RDW and brain death in future.

[Organ donation after determination of brain death : Legal aspects and practical approach]

The prerequisites for post-mortem organ donation in Germany include the determination of irreversible loss of brain function, consent to organ donation, and the exclusion of medical contraindications. In addition, mainly because of the shortage of donor organs in Germany and the sometimes controversial social and media discussions on the topic of organ donation, all physicians involved in the donation process must be familiar with the relevant laws, guidelines, and procedural instructions. This applies especially to those who are to carry out the verification of irreversible brain death. Only then, can they act safely in this challenging situation and serve as competent consultants for all involved.

Brain death in children: is computed tomography angiography reliable as an ancillary test?

BACKGROUND

The diagnosis of brain death is primarily clinical. Sometimes ancillary tests are needed.

OBJECTIVE

This study compared sensitivity and interobserver agreement of the 10-, 7- and 4-point CT angiography scoring systems for the diagnosis of brain death in children.

MATERIALS AND METHODS

CT angiography examinations of 50 pediatric patients with a clinical diagnosis of brain death were evaluated according to 10-, 7- and 4-point scoring systems. Images were evaluated by two radiologists who considered the vessel opacification first in the arterial phase (A₀-V₅₀) and then in the venous phase (A₀-V₅₀). We evaluated interobserver agreement for the assessment of vessel opacification and diagnosis of brain death. We compared the differences among brain death diagnoses between children with craniotomy-craniectomy defects, open fontanelles and preserved bone integrity. We subdivided children into two groups according to age: ≤ 2 years and > 2 years. We calculated sensitivities according to age groups.

RESULTS

Using the clinical exam as the reference standard, we found sensitivities for 10-, 7- and 4-point scoring systems to be 70%, 88% and 92% in the A₀-V₅₀ method and 40%, 82% and 82% in the A₅₀-V₅₀ method, respectively. Percentage agreement between readers was 78% for the 7-point scale using the A₀-V₅₀ method and more than 90% for other scoring systems for both the A₀-V₅₀ method and the A₅₀-V₅₀ method. The sensitivity was much lower in children with open anterior fontanelles compared to the groups with preserved bone integrity and with a craniotomy-craniectomy defect.

CONCLUSION

Just as in adult age groups, in children the 4-point scale appears to be more sensitive than the 10- and 7-point scales for CT angiography-based assessment of brain death. Because the scoring systems have similar sensitivities, they could be used as ancillary tests in pediatric cases.

The Legal Void Outside Brain Death in India: The Legislative Need of 'DNR' in Brain Death

Objective

The legal definitions of brain death are tantamount for legal dogmas and sometimes criminal intimidation of the treating doctors. The tests for brain death are only applicable to patients planned for organ transplantation. We intend to discuss the necessity of the "Do Not Resuscitate (DNR)" legislature in cases of brain death patients and applicability of tests for brain death irrespective of the intention for organ donation.

Methods

A comprehensive review of the literature was performed till May 31, 2020 from the MEDLINE (1966 to July 2019) and Web of Science (1900 to July 2019). Search criteria included all publications with the MESH terms: "Brain Death/legislation and jurisprudence"[Mesh] OR "Brain Death/organization and administration"[Mesh] AND "India" [Mesh]. We also discuss the different opinions and implications of brain death versus brain stem death in India with the senior author (KG) who was responsible for South Asia's first multi-organ transplant after certifying brain death. Additionally, a hypothetical scenario of a DNR case is discussed in the current legal paradigm of India.

Results

The systematic search yielded only five articles reporting a series of brain stem death cases with an acceptance rate of organ transplant among brain stem deaths being 34.8%. The most common solid organs transplanted were the kidney (73%) and liver (21%). A hypothetical scenario of a DNR and possible legal implications of the same under the current 'Transplantation of Human Organs Act (THOA)' of India remains unclear. A comparison of brain death laws in most Asian countries shows a similar pattern regarding the declaration of brain death and the lack of knowledge or legislature regarding DNR cases.

Conclusion

After the determination of brain death, discontinuation of organ support requires the consent of the family. The lack of education and the lack of awareness have been major impediments in this medico-legal battle. There is also an urgent need to make laws for cases that do not qualify for brain death. This would help in not only realistic realization but also better triage of the health care resources while legally safeguarding the medical fraternity.

A thematic analysis of a survey of hospital chaplains on death by neurologic criteria

INTRODUCTION

Little is known about chaplains' views on brain death/death by neurologic criteria (BD/DNC). Thematic analysis of comments made by hospital chaplains about BD/DNC can illuminate their perspectives on working with patients, families, and interdisciplinary teams during assessment for BD/DNC.

MATERIALS AND METHODS

In an electronic survey distributed to members of five chaplaincy organizations between February and July 2019, we elicited free-text comments about BD/DNC. We performed a thematic analysis of the comments.

RESULTS

Four themes were present: (1) definition of life and death, (2) respect with a subtheme of physician obligation, (3) collaboration with a subtheme of communication, and (4) education with a subtheme of scepticism.

CONCLUSIONS

Hospital chaplains are essential members of the interdisciplinary team involved in BD/DNC evaluation. They aim to ensure the interaction between families and the interdisciplinary team at the boundary of life and death and the intersection between religion and medicine is respectful, collaborative, and educational.

Neuropathologic findings in a young woman 4 years following declaration of brain death: case analysis and literature review

Brain death (death by neurologic criteria) is declared in 2% of all in-hospital deaths in the United States. Published neuropathology studies of individuals maintained on cardiorespiratory support are generally decades old, and notably include only 3 cases with long intervals between brain and "somatic" death (68 days, 101 days, 20 years). Here, we share our observations in a young woman supported for nearly 4½ years following declaration of brain death after oropharyngeal surgery. While limited by tissue availability and condition, we found evidence of at least partial perfusion of the superficial cerebral and cerebellar cortices by external carotid and vertebral arteries (via meningeal and posterior pharyngeal branches), characterized by focal cellular reaction and organization. Dural venous sinuses had thrombosis and recanalization, as well as iron deposition. In nonperfused brain areas, tissue "mummification," akin to that seen in certain postmortem conditions, including macerated stillbirths and saponification (adipocere formation), was identified, and are reviewed herein. Unfortunately, correlation with years-earlier clinical and radiographic observations was not possible. Nevertheless, we feel that our careful neuropathologic inspection of this case expands the understanding of the spectrum of human brain tissue alterations possible in a very rarely seen set of conditions.

Differences in Perspective Toward Organ Donation Between Second-Year and Final-Year Medical Students in a Thai Medical School

Medical students, as prospective physicians, should develop a good attitude toward organ donation since physicians can positively affect the decision to donate organs. This study compared perspectives toward organ donation between Thai second-year and final-year (sixth-year) medical students, and explored changes that might occur during medical school training. Second-year and final-year medical students at the Faculty of Medicine Siriraj Hospital, Mahidol University, were invited to participate in the survey. The demographic data of the participants were collected and the attitudes toward organ donation were measured from the questionnaire. In total, 89 second-year and 60 final-year medical students voluntarily enrolled in the study. Nearly all the participating medical students supported organ donation and were willing to donate their organs after death. The majority of participants had a positive attitude toward organ donation in many perspectives, e.g., their beliefs, family issues, and donation procedure. There was a statistical difference between the proportion of second-year and final-year students who supported that a brain death condition is a true death (59.6% and 93.3%, respectively, p < 0.001) and who did not feel uncomfortable mentioning organ donation (82.0% and 96.7%, respectively, p = 0.007). In conclusion, there were significant differences in perspective between second-year and final-year students regarding brain death and discomfort perceived during organ donation-related situations. Experience gained during medical school could generate a more positive attitude toward organ donation. Therefore, medical schools play an essential role in nurturing a positive perspective toward organ donation in future physicians.