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Objective: To evaluate the feasibility of using the Sentinella® portable gamma-camera for the diagnosis of brain death (BD)., Design: A prospective, observational feasibility study was carried out., Setting: Intensive Care Unit of a third level hospital., Patients: Consecutive recording was made of the adults diagnosed with brain death based on clinical criteria following admission to the Intensive Care Unit in the period from January to December 2017., Interventions: The procedure was performed at the patient bedside with the intravenous administration of technetium 99 metastable hexamethylpropylene amine oxime. The absence of perfusion in the cerebral hemispheres and brainstem was described as a pattern consistent with BD. The diagnosis was correlated to the transcranial Doppler and / or electroencephalographic findings., Results: A total of 66.1% of the patients were men with an average age of 60 years [IQR: 51-72]. The most frequent causes resulting in BD were hemorrhagic stroke (48.2%, n=27), followed by traumatic brain injury (30.4%, n=17), ischemic stroke (10.7%, n=6) and post-cardiac arrest anoxic encephalopathy (7.1%, n=4). A clinical diagnosis of BD was made in all cases, and the portable gamma-camera confirmed the diagnosis in 100% of the patients with a pattern characterized by the absence of brain perfusion. In addition, the results were compared with the transcranial Doppler findings in 46 patients, confirming the presence of diastolic reverberation and / or systolic peaks. The electroencephalographic tracing was obtained in 10 cases, with the appearance of electrical silence, due to the absence of an acoustic window in the transcranial Doppler study., Conclusions: A portable gamma-camera could be a useful and feasible tool for the diagnosis of BD., (Copyright © 2018 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.)

Transcranial Doppler ultrasound is able to demonstrate cerebral circulatory arrest associated to brain death, being especially useful in sedated patients, or in those in which complete neurological exploration is not possible. Transcranial Doppler ulstrasound is a portable, noninvasive and high-availability technique. Among its limitations, mention must be made of the absence of acoustic windows and false-negative cases. In patients clinically diagnosed with brain death, with open skulls or with anoxia as the cause of death, cerebral blood flow can be observed by ultrasound, since cerebral circulatory arrest is not always synchronized to the clinical diagnosis. The diagnostic rate is therefore time-dependent, and this fact that must be recognized in order to avoid delays in death certification. Despite its limitations, transcranial Doppler ulstrasound helps solve common diagnostic problems, avoids the unnecessary consumption of resources, and can optimize organ harvesting for transplantation., (Copyright © 2014 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.)

Background and Objective: The use of transcranial doppler (TD) for the assessment of critical neurological patients and brain death (BD) is steadily growing. In this study we describe the daily clinical practice around BD diagnosis and compare the usefulness of TD, including advantages and shortcomings, with that of other tests., Patients and Method: A series of 100 patients diagnosed of brain death is presented including the demographic and clinical data as well as the results of ancillary tests (CE)., Results: Fifty eight patients were males with a mean age of 46. The most frequent etiology of coma was spontaneous cerebral hemorrhage. Central nervous system depressants had been administered to 62 patients within a few hours prior to the diagnosis. When ancillary tests were performed, only 55% patients fulfilled the currently accepted clinical criteria for brain death. TD was performed in 44 patients and 80% of them showed a pattern supporting a brain death diagnosis. Definitive diagnostic tests were electroencephalogram (EEG) in 53% patients and TD in 35% of them. In ten cases, discrepancies were observed between the results offered by these tests., Conclusions: Transcraneal Doppler stands out as a safe, fast, inexpensive and bloodless method of assessment of the critical neurological patient and for BD diagnosis. It is the choice test in the presence of central nervous system depressant drugs, abuse of substances or coma of unknown etiology. The main limitations of this technique are the presence of extensive craniotomies and the absence of an adequate acoustic window.

Introduction and Aims: Brain death causes myocardial impairment by some mechanisms not yet well understood. The aim of this work was to assess the echocardiographic features found in these patients and their implication in donor selection for heart transplantation., Methods: With this aim, we have studied 38 consecutive patients with brain death assessed as possible donors for heart transplant in our hospital in the last 3 years. Age was 23 +/- 13 years; 77% were male. No history of cardiac disease was present in any patient. An adequate transthoracic echocardiogram was obtained in 74% of patients; transesophageal view was used in the remaining 26%., Results: Echocardiogram was strictly normal in only 14 patients (37%). Mild valvular alterations were found in 5 patients (13%); a dilated aortic root in 1 (3%); moderate concentric left ventricular hypertrophy in 5 (14%); mild pericardial effusion in 1 (3%); mild septal hypokinesia with normal left ventricular ejection fraction in 4 (10%); abnormal left ventricular diastolic function in 7 (18%); and diffuse hypokinesia with ejection fraction less than 60% in 14 (37%). In 7 patients (18%) ejection fraction was lower than 40% (one of them was cocaine-addict). Mean ejection fraction was 59 +/- 15% (23 to 83%). Only 2 of the 19 (10%) donor hearts implanted in our hospital showed early dysfunction after transplant, but no relation to pretransplant ejection fraction was found. Ejection fraction increased from 62% pretransplant to 73% at one week after transplant in the other 17 cases., Conclusions: Brain death commonly causes alterations of left ventricular function, and this impairment is severe in almost 20% of cases. These echocardiographic features must be known when selection of donors for heart transplantation is concerned.

Background: Transcranial Doppler examination (TCD) is a non invasive method capable of detecting the interruption of cerebral flow in patients with criteria of brain death. Its recognition as an alternative to isoelectric EEG for the diagnosis of brain death requires previous validation., Methods: Twenty-six patients in profound coma were examined by TCD. Of 23 patients with technically adequate study 13 manifested clinical criteria and EEG of brain death. Of these patients 9 had received barbiturate treatment and 4 had not., Results: Changes in the flow waves of the TCD were observed in the form of diastolic reflux or systolic points of slight amplitude without diastolic flow in at least 2 arteries in 12 of 13 patients with criteria of brain death (sensitivity = 92%) and in none of the 10 patients without criteria of brain death (specificity = 100%). The use of barbiturates did not modify the normal anterograde flow detected by TCD in the absence of criteria of brain death., Conclusions: Transcranial Doppler is a good method for confirming the clinical diagnosis of brain death, fundamentally in patients undergoing treatment with drugs depressing the central nervous system.