Criteria of brain death. Spinal reflexes in 45 personal studies

In 45 patients without spontaneous breathing or cranial reflexes, and in whom blood pressure had to be supported, spinal reflexes were obtained in 60% and polysynaptic spinal reflexes in 33%. In all cases angiography showed cerebral circulatory arrest and/or repeated EEG recording gave an isoelectric line. The presence of spinal reflexes, appearing most frequently 6-36 h after death (which we defined as a sudden fall in blood pressure below 80 mm Hg with absence of spontaneous breathing) is not in contradiction with the assumption of brain death. 9 patients without signs of intoxication showed, in addition, a fall in body temperature below 34 degrees C. Such a fall in body temperature also in agreement with the diagnosis of brain death.     

Digital subtraction angiography--a new approach to brain death determination in the newborn

The diagnosis of brain death in the newborn infants is elusive and often difficult. The lack of cerebral blood flow has become an identified criterion for loss of cerebral function. The diagnosis can be obtained by the technique of digital subtraction angiography, which is presented in two case reports demonstrating the utility of this technique.     

Spinal cord emergencies: false reassurance from reflexes

Emergency physicians need to understand the potential for false reassurance in the interpretation of reflex examination data. Neurologic consultation should be sought when classic signs are lacking, but other evidence causes suspicion. Changes in teaching emphasis and acute practice are needed, since the stakes may be high and time is of the essence. We have responded to the insights gained from this study by augmenting in-service and continuing medical education teaching and by implementing guidelines to assist EPs. We have emphasized the importance of spotlighting high-risk patients, as exemplified above, and of taking advantage of neurologic or neurosurgical consultation. Where in-person consultation is less available, the use of guidelines and remote consultation should be able to help direct further examination, diagnostic formulation, and the need for imaging decisions. Given the potential for severe negative outcome if spinal emergencies are not optimally managed, we must give the teaching of these issues high priority.     

Continuous pressure is preferred to flow triggering of respiration in the apnea test following the protocol for brain death determination

The apnea test is part of the brain death protocol of the National Health Council. If the patient is being given positive end-pressure respiration, he must not be uncoupled from the respirator. The apnea test should then be done by means of continuous positive airway pressure. Pressure triggering rather than the extremely sensitive flow triggering should then be chosen to trigger the respiration, since otherwise the patient may unjustifiably be declared 'not brain dead' as a result of slight aspecific movements (bumping against the bed, beating of the heart).     

From death concepts to brain death diagnostic criteria

The authors present considerations about death and brain death concepts, as well the legal aspects for its diagnosis in Brazil. They also present the UNICAMP Protocol for the Diagnosis of Brain Death, revised and according with the current law, with standard techniques for the diagnostic exam. They emphasize the importance of a mature ethical position for this frequent and challenging situation.     

Maternal brain death during pregnancy

BACKGROUND: An association between smoking and impaired wound healing has been reported in retrospective studies. The smoking status of a surgical patient may be confounded by social and medical parameters. We have evaluated the effect of smoking in a test wound in volunteers, with special reference to a reliable scientific match between smokers and nonsmokers. METHODS: In a prospective open study with blinded assessment, 19 smoking (20 cigarettes/day) and 18 nonsmoking healthy volunteers were matched with respect to baseline characteristics. The deposition of total protein and mature collagen (expressed as hydroxyproline) was assessed in an expanded polytetrafluoroethylene wound healing model implanted subcutaneously for 10 days. RESULTS: The nonsmokers had a 1.8 times higher median amount of hydroxyproline than the smokers (p < 0.01). The deposition of hydroxyproline was negatively correlated with the consumption of tobacco both before (r = -0.44; p < 0.01) and during the study (r = -0.48; p < 0.005). The impairment was specific for the production of collagenous proteins and not other proteins. CONCLUSIONS: The synthesis of subcutaneous collagen in smokers is specifically impeded, indicating an impaired wound-healing process. Because mature collagen is the main determinator of strength of an operative wound, the results support the view that patients should be advised to stop smoking before an operation.     

Transcranial Doppler assessment of brain death in children

Airborne dust in pig houses causes health problems for humans with full-time employment in pig houses. Many attempts have been made to reduce the dust burdens, but often without sufficient results. At Research Centre Bygholm ten different possibilities for dust reduction have been tested in the test section, and the results are evaluated on the basis of results obtained simultaneously in an identical control section. Until now, the two most efficient methods are addition of fat to the pigs' diet and spraying a thin layer of rape seed oil in the animal house. By adding 4% of fat to the diet, a reduction of 50% can be seen, and by spraying 5 g of rape seed oil daily per pig place, the aerial dust concentration can be reduced to about 75%. The costs are about 1 DM/pig at a price of rape seed oil of 2 DM/l.     

Magnetic resonance imaging of brain death

The db/db mutant mouse is a rodent model of genetic diabetes that develops renal glomerular lesions with striking mesangial matrix accumulation by the age of 16 weeks, after 8-10 weeks of sustained hyperglycemia. However, abnormalities in renal function that antedate or accompany the appearance of these pathologic changes, which resemble those found in human diabetes, have not been delineated. We therefore examined renal function in young db/ db mice and their nondiabetic db/m littermates from the age of 8 through 15 weeks. Serum creatinine and blood urea nitrogen concentrations at the onset of diabetes in db/db mice did not differ significantly from mean concentrations in db/m controls. An elevated creatinine clearance, due in large part to increased body weight, and increased urinary albumin excretion were observed in db/db compared with db/m mice soon after establishment of sustained hyperglycemia. A relative reduction in creatinine clearance was demonstrable in db/db mice at the age of 15 weeks, coincident with the appearance of overt compromise in renal function manifested by frank increases in the serum creatinine and blood urea nitrogen. The findings indicate that the well-documented glomerular pathology in db/db mice is accompanied by definable alterations in renal function, which are similar in chronology and nature to those found in human diabetes.     

Tc-99m HMPAO cerebral scintigraphy. A reliable, noninvasive method for determination of brain death

To investigate the relationships between the mammographic aspects (according to Broberg), proliferative activity and hormone receptor status, we studied 165 patients subjected to radical mastectomy for operable breast cancer. The highest percentage of estrogen receptor-positive cases was observed in mammograph class I (p < 0.02) while classes III and V were highest in progesterone receptor-positive cases. Proliferative activity (111 cases) was significantly lower in class I and IV with respect to all other classes (p < 0.03 and p < 0.01, respectively). This study suggests that certain mammographic signs can be related to the biological characteristics of breast cancer.     

Unexpected death during a brain scintigraphy

Brain scintigraphy was performed for differential diagnosis of suspected subdural hemorrhage in a 79-year-old woman. Planar pertechnetate (99mTcO4-) brain scan with AP, PA, lateral and vertex projections was planned. The procedure was started with AP-projection, continuing with lateral projections. After these images the patient was determined dead and the planned scannings were aborted. There was a clear difference in the intracranial uptake (choroid plexuses) in the lateral views as well as in the uptake in the venous sinuses. The findings in the AP view were normal and no signs of subdural hemorrhage were observed. The patient died during a routine nuclear medicine procedure, and cessation of intracranial circulation was observable on 99mTcO4- scans; the lack of uptake in cerebral sinuses confirmed the lack of intracerebral flow. In this rare case, brain death could be timed accurately using a static nuclear medicine procedure. Autopsy confirmed sudden brain circulatory disorders and general arteriosclerosis.     

A clinico-neuropathological study on brain death

A clinico-neuropathological study was conducted on 60 cases of brain death, 36 males and 24 females, ranging in age from 11 to 81 years, the average being 49.4 years. Of these, 29 patients died of cerebrovascular disease. The average duration of brain death was 99 hours. The mean weight of the brain was 1466 g. Neuropathological findings were brain edema, congestion, herniation and various subarachnoid hemorrhages. Histologically, the cytoplasm of neurons was pale and ghost-like. In the white matter, myelin staining was pale, and nuclei of the glial cells were shrunken and piknotic. Autolysis of the cerebellar granular layer and the pituitary gland was evident in all cases. No reactive astrocytosis or infiltration of the cells in or around necrotic tissue could be seen. In eight cases, there was laminar infiltration of neutrophils in the superficial area of the cerebrum and brain stem, possibly due to temporary or partial recirculation. Correlation between the degree of autolysis and duration of brain death was observed, but no relationship between the degree of autolysis and the difference of underlying disease could be found. Autolysis in the cerebral cortex, thalamus, tegmentum of the brain stem, cerebellar granular layer and pituitary gland was most prominent. However, neuropathological diagnosis of underlying diseases could be made even in brain death. Histologically, the cases of brain death differed from those of cardiac arrest-induced encephalopathy and from those of long postmortem autopsy.     

Value and worthlessness of clinical studies in the diagnosis of brain death

Death was ever determined on the basis of extinguished partial functions of the entire organism (partial death). In intensive medicine with its possibilities of reanimation, with its possibilities of artificial maintenance of breathing and circulation the individual death of man is equated with his cerebral death. It comes only under conditions of reanimation and nearly always shows a clinically recognizable development. Practically above all "the syndromes in the forefield of cerebral death" are of interest as well as its obligatory and optional symptoms, the valency of which was critically tested. A 5-year-analysis (1969 to 1973) of 487 deaths in an internal intensive therapy unit (18% of mortality) was shown that causes, frequency and age distribution of the mortal conditions of disease as well as the average survival time of 4.5 days, in which cases, however, 43% of all deaths occurred within the first 24 hours, very rarely caused us to establish the irreversibility of the loss of the cerebral function on account of an organic dysfunction, but rather resulting from the question of the interruption of an absurd reanimation.     

A study of cell death in Werdnig Hoffmann disease brain

We examined the occurrence of apoptotic cell death in the autopsied brains of four patients with Werdnig Hoffmann disease (WH), using TdT-mediated DIG-dUTP nick end labeling (TUNEL) and immunohistochemistry for apoptosis-related proteins. Three of the four patients, aged over 6 months, exhibited TUNEL-positive cells in the lateral nuclei of the thalamus, and one of the three patients also had TUNEL-positive cells in the cerebral cortex. The labeled nuclei did not show characteristic features such as nuclear fragmentation or apoptotic bodies, and synaptophysin-positive granules were observed around some of the TUNEL-positive cells, although none of the antibodies against glial markers could visualize TUNEL-positive cells. TUNEL-positive cells were not observed in other regions examined, including the spinal cord, medulla and cerebellum or in the brains of three age-matched controls. There were neither immunopositive structures for bcl-2 or p53 nor alteration of in situ expression of bcl-xs/l or bax in any subject, and the TUNEL-positive cells lacked immunopositivity against apoptosis-related proteins. The presence of these TUNEL-positive cells might suggest latent neurodegeneration in the thalamus before central chromatolysis of neurons or neuronal loss appears, although it is not clear whether apoptotic cell death is involved in this degenerative process.     

Irrecoverable brain damage after resuscitation: brain death and other syndromes

The diagnosis of diabetes mellitus depends primarily on the doctor being continually aware of this common, important and treatable disease. The previous two articles in this series have described the prevalence of the disease, and the warning signals suggesting that the disease may be present.     

Cloning and expression of the programmed cell death regulator Bad in the rat brain

The Bcl-2 family of proteins consists of both antagonists (e.g. Bcl-2) and agonists (e.g. Bax) that regulate apoptosis and compete through dimerization. In the present study we cloned the cDNA encoding the rat brain BAD, a distant member of the Bcl-2 family that was shown to promote cell death. The cloned cDNA encoded a protein of 205 amino acids, containing three putative Bcl-2 homology domains (BH1, BH2 and BH3) and no C-terminal signal-anchor sequence. The predicted amino acid sequence was identical to the Bad-cDNA recently cloned from the rat ovary with the exception of a stretch of six amino acids, thus indicating the existence of two Bad alternative splice variants or a sequence artifact in the rat ovary Bad-cDNA. Immunohistochemical analysis in the rat brain revealed the exclusive expression of Bad in the epithelial cells of the choroid plexus, a result which is consistent with a very specialized function of Bad in the brain.