Diagnosis Of Cerebral Circulatory Arrest Research Articles

Abstract TP115: Variability Of Transcranial Doppler Criteria In The Determination Of Cerebral Circulatory Arrest

Introduction: Transcranial Doppler (TCD) is a commonly used testing modality in the diagnosis of cerebral circulatory arrest (CCA). There is currently no consensus in the United States for which vessels must be insonated to establish a CCA diagnosis. We evaluated TCD-CCA studies using four categories of vessel selection to determine which set of criteria would be most restrictive. Methods: We reviewed all TCD studies from our center that were performed for the evaluation of CCA. For each study, two readers determined whether the bilateral middle cerebral arteries (MCA) and the basilar artery demonstrated a pattern typical of CCA. In cases where one or more of these three primary vessels could not be located, specific proximal vessels were evaluated and used as a surrogate. Surrogate vessels for the MCAs included the ipsilateral carotid siphon and the terminal internal carotid artery. Surrogate vessels for the basilar artery required the evaluation of both intracranial vertebral arteries. A diagnosis of CCA was given according to four different criteria: absent diastolic flow in [1] bilateral MCAs and the basilar artery, [2] bilateral MCAs only, [3] the three primary vessels or a surrogate vessel when a primary vessel could not be located, and [4] bilateral MCAs or a surrogate vessel when either MCA could not be located. Results: Fifty-five TCD studies were included in this analysis. Of these, 17 studies were not able to insonate one of the three primary vessels. Seven of these incomplete studies included surrogate vessels for the absent primary vessel. When all three primary vessels were insonated, 17 studies were consistent with CCA. Twenty-four studies met CCA criteria when only the MCAs were evaluated, 19 studies met criteria when the primary vessels or a surrogate vessel were evaluated, and 26 studies met criteria when only the MCAs or their surrogate vessels were evaluated. Conclusion: The results of this analysis suggest that when different criteria for CCA are applied, the rates of CCA diagnosis change considerably. Since CCA is often a critical part of establishing death by neurologic criteria, it is important that national standards for a TCD protocol are established.

Implementation of Computed Tomography Angiography (CTA) and Computed Tomography Perfusion (CTP) in Polish Guidelines for Determination of Cerebral Circulatory Arrest (CCA) during Brain Death/Death by Neurological Criteria (BD/DNC) Diagnosis Procedure.

Background: Brain death/death by neurologic criteria (BD/DNC) guidelines are routinely analyzed, compared and updated in the majority of countries and are later implemented as national criteria. At the same time, extensive works have been conducted in order to unify clinical procedures and to validate and implement new technologies into a panel of ancillary tests. Recently evaluated computed tomography angiography and computed tomography perfusion (CTA/CTP) seem to be superior to traditionally used digital subtraction angiography (DSA), transcranial Doppler (TCD) and cerebral perfusion scintigraphy for diagnosis of cerebral circulatory arrest (CCA). In this narrative review, we would like to demonstrate scientific evidence supporting the implementation of CTA/CTP in Polish guidelines for BD/DNC diagnosis. Research and implementation process: In the first of our base studies concerning the potential usefulness of CTA/CTP for the confirmation of CCA during BD/DNC diagnosis procedures, we showed a sensitivity of 96.3% of CTA in a group of 82 patients. CTA was validated against DSA in this report. In the second study, CTA showed a sensitivity of 86% and CTP showed a sensitivity of 100% in a group of 50 patients. In this study, CTA and CTP were validated against clinical diagnosis of BD/DNC supported by TCD. Additionally, we propose our CCA criteria for CTP test, which are based on ascertainment of cerebral blood flow (CBF) < 10 mL/100 g/min and cerebral blood volume < 1 mL/100 g in regions of interest (ROIs) localized in all brain regions. Based on our research results, CTA/CTP methods were implemented in Polish BD/DNC criteria. To our knowledge, CTP was implemented for the first time in national guidelines. Conclusions: CTA and CTP-derived CTA might be in future the tests of choice for CCA diagnosis, proper and/or Doppler pretest might significantly increase sensitivity of CTA in CCA diagnosis procedures. Whole brain CTP might be decisive in some cases of inconclusive CTA. Implementation of CTA/CTP in the Polish BD/DNC diagnosis guidelines does not show any major obstacles. We believe that in next edition of “The World Brain Death Project” CTA and CTP will be recommended as ancillary tests of choice for CCA confirmation during BD/DNC diagnosis procedures.

Addressing a Diagnosis of Brain Death in Hypernatremia Situation

Hypernatremia and the state of plasma hypertonia are part of the alterations of insipid diabetes that are integrated to the brain death (BD) syndrome. Hypernatremia should be corrected as early as possible to make the clinical diagnosis of BD and to avoid its potential deleterious effect on the subsequent operation of the liver graft. Transcranial Doppler is a very valuable tool for the diagnosis of cerebral circulatory arrest associated with BD. The correction of natremia is made through the use of hypotonic solutions, and using of pyrogen-free distilled water intravenously in special cases, which controls the possibility of hemolysis in the donor. In our study, isolated severe hypernatremia corrected before ablation was not associated with liver graft failure in the recipient.

Brain ultrasonography: methodology, basic and advanced principles and clinical applications. A narrative review.

Brain ultrasonography can be used to evaluate cerebral anatomy and pathology, as well as cerebral circulation through analysis of blood flow velocities. Transcranial colour-coded duplex sonography is a generally safe, repeatable, non-invasive, bedside technique that has a strong potential in neurocritical care patients in many clinical scenarios, including traumatic brain injury, aneurysmal subarachnoid haemorrhage, hydrocephalus, and the diagnosis of cerebral circulatory arrest. Furthermore, the clinical applications of this technique may extend to different settings, including the general intensive care unit and the emergency department. Its increasing use reflects a growing interest in non-invasive cerebral and systemic assessment. The aim of this manuscript is to provide an overview of the basic and advanced principles underlying brain ultrasonography, and to review the different techniques and different clinical applications of this approach in the monitoring and treatment of critically ill patients.

Critical Care Ultrasound

Critical Care Ultrasound is an electronic and print textbook that presents the use of ultrasound in intensive care. Although thorough enough for an in-depth understanding of critical care ultrasound, the concise text and excellent visuals allow this book to be used as a quick reference as well. The authors write the book with a concept they call “The Holistic Approach” to an ultrasound examination. This defines the critical care ultrasound as the part of a patient examination, which visualizes anatomic structures and function “in their live, interconnected state.” Therefore, rather than merely describe a specific ultrasound modality, the authors write each chapter within the context of the physiology, pathophysiology, and anatomy. Section I outlines the fundamental concepts of ultrasound, including a review of physics, imaging modes, image optimization, and common artifacts encountered during an examination. The section closes with a comprehensive visual review of ultrasound anatomy and pathology. Systems reviewed include head and neck, chest, abdominal, and musculoskeletal. Section II details the use of ultrasound in neurocritical care. The section opens with a chapter on transcranial Doppler. The authors describe its multiple applications, including vasospasm monitoring after aneurysmal subarachnoid hemorrhage, ischemic stroke evaluation, diagnosis of cerebral circulatory arrest, and assessment of autoregulation. Included in this section is a description of optic nerve sheath diameter as a surrogate for intracranial pressure. The text progresses to Section III: Vascular Ultrasound, beginning with an overview of arterial and venous system anatomy and pathophysiology. The deep venous thrombosis chapter describes both the basic and advanced ultrasound diagnostic techniques and strategies for a successful examination. The central venous and arterial access chapters go beyond basic ultrasound-guided technique. The text details advanced knowledge of catheterization including ultrasound-guided subclavian access, evaluation of traumatic hematoma after line placement, and criteria for choosing the appropriate vein for cannulation. The book transitions to the general chest ultrasound and echocardiography sections. The chest section describes the ultrasound as an adjuvant in diagnosing common lung pathologies including pneumothorax, pleural effusion, and pneumonia. The section includes the use of ultrasound in trauma, acute dyspnea, acute respiratory distress syndrome, and the difficult to wean mechanically ventilated patient. The echocardiography chapters describe the use of echocardiography in the evaluation of circulatory failure, septic shock, pulmonary embolism, and cardiac arrest. The hemodynamic monitoring section first presents general concepts, such as static-based parameters, dynamic arterial waveform analysis, and passive leg raising. The authors tie the use of ultrasound to these basic concepts. They describe measuring fluid responsiveness by both static and dynamic ultrasound measurements. These include measurement of inferior vena cava diameter, mitral valve inflow patterns, and respiratory variations in both aortic and inferior vena cava flow patterns. A highlight of the section is a well-organized flow chart describing the use of ultrasound as a guide in the evaluation of circulatory failure. The book transitions to abdominal and emergency ultrasound. This includes chapters on the extended FAST examination and ultrasound evaluation of abdominal compartment syndrome. There is an excellent online video, which demonstrates a FAST examination being performed on a sample patient. The final clinical section discusses soft tissue and miscellaneous uses of ultrasound. These chapters include details on evaluating musculoskeletal injury and masses. In addition, there is a chapter on ultrasound-guided percutaneous tracheostomy, which highlights the use of ultrasound in determining stoma site selection and tracheostomy size. The electronic version of the textbook is available in 3 formats: an online version through Expert Consult, as a PDF, and as an ePub book. The Expert Consult version of the book is simple and navigable. There are videos and pictures, which are organized as both a list and embedded in the chapters. This organization allows the reader to either quickly select a video for quick review or view the content within the chapter for more detail. In addition, each online chapter includes a detailed set of references if further information on a topic is desired. Unfortunately, the PDF version of the book does not provide the same seamless integration. The links provided in the PDF documents are irregular and do not always link to the referenced material. In conclusion, Critical Care Ultrasound is an excellent handbook for the intensivist or anesthesiologist. The greatest strength of the book, however, is its greatest weakness. At times, because the chapters are so brief, there are details that are omitted. Furthermore, the text does not transition well to the PDF format. Regardless of the few weaknesses, Critical Care Ultrasound is an excellent addition to the library of any intensivist or anesthesiologist. Anthony F. Dempsey, MDJudson Mehl, DODepartment of AnesthesiologyUniversity of Kentucky College of MedicineLexington, Kentucky[email protected]

Transcranial Doppler in the Diagnosis of Cerebral Circulatory Arrest: Cases of the National Institute of Donation and Transplantation of Uruguay

BackgroundTranscranial Doppler (TCD) is an auxiliary method for the diagnosis of cerebral circulatory arrest (CCA). The objective of this work was to appreciate the efficiency of the method in the diagnosis of the CCA and its outcome in situations such as decompressive craniectomy (DC). MethodsIn this descriptive, retrospective study, conducted between 2000 and 2012, variables considered were causes of brain death (BD), age, sex, application reason, CCA patterns, and CCA patterns in DC. As a statistical approach, Pearson χ2 distribution was used. A total of 522 cases were analyzed; mean patient age was 30 ± 19 years, and 61% were men. ResultsThe principal causes of BD were traumatic brain injury, 44%; subarachnoid hemorrhage, 20%; and post–cardiac arrest anoxic ischemic injury, 17%. TCD was requested by contraindication to apnea testing in 84% of cases, and it diagnosed CCA in 79%. The most frequent pattern of CCA was the systolic spike (70%). CCA was diagnosed in patients with DC in 43% (23/54) compared with 79% (369/468) in those patients without this procedure (P = .0001), with the systolic spike being the most frequent pattern (48%). ConclusionsTCD is a useful and highly specific tool for the diagnosis of CCA that occurs with BD, diminishing its performance significantly in patients with DC.

CT Angiography in the Diagnosis of Brain Death.

SummaryBrain death is defined as the irreversible cessation of functioning of the entire brain, including the brainstem. Brain death is principally established using clinical criteria including coma, absence of brainstem reflexes and loss of central drive to breathe assessed with apnea test. In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful. The objective of ancillary tests in the diagnosis of brain death is to demonstrate the absence of cerebral electrical activity (EEG and evoked potentials) or cerebral circulatory arrest. In clinical practice catheter cerebral angiography, perfusion scintigraphy, transcranial Doppler sonography, CT angiography and MR angiography are used. Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death. CT angiography has recently attracted attention as a promising alternative to catheter angiography – a reference test in the diagnosis of brain death. Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada). This paper reviews technique, characteristic findings and criteria for the diagnosis of cerebral circulatory arrest in CT angiography.

Improved Efficacy of Transcranial Doppler Sonography in Confirming Cerebral Circulatory Arrest in Brain Death Using the Transorbital Approach

Transcranial Doppler sonography (TCD) confirmation of cerebral circulatory arrest (CCA) in brain death (BD) is unfeasible in patients with absent temporal bone windows. We added the transorbital approach in the TCD protocol for the diagnosis of CCA and compared findings with angiography. Additionally, we evaluated whether reporting the confirmation of CCA to relatives of brain-dead patients improves their comprehension and satisfaction with the medical information.

The Value of Transcranial Doppler Sonography With a Transorbital Approach in the Confirmation of Cerebral Circulatory Arrest

Objective Transcranial Doppler sonography (TCD) provides accurate confirmation of cerebral circulatory arrest (CCA) in brain death (BD), but is not feasible in patients with absent temporal bone windows. We added the transorbital approach in the TCD protocol for the diagnosis of CCA and compared findings with angiography. Furthermore, we evaluated whether reporting the angiographic and sonographic confirmation of CCA to relatives of brain-dead patients improves their comprehension and satisfaction with the medical information. Patients and Methods Eighty-two clinically brain-dead patients underwent 4-vessel angiography, TCD of the basilar and middle cerebral arteries, and transorbital Doppler sonography (TOD) of the internal carotid arteries. Relatives were randomly allocated to 41 in whom BD was presented as a clinical diagnosis (group A) and to 41 in whom BD was presented as a clinical diagnosis confirmed by TCD and angiography (group B). Comprehension and satisfaction of the relatives were assessed using an interview and a questionnaire. Results Both angiography and TCD verified CCA in all cases ( k = 1). In 11 patients with failure of the transtemporal approach, CCA was confirmed by the transorbital recordings. The addition of TOD enabled 15.5% more cases of CCA to be diagnosed by TCD. Group B exhibited improved comprehension and satisfaction rates ( P < .05). Conclusions The addition of TOD increases the efficacy of TCD in confirming CCA in BD. Reporting confirmation of CCA to families of brain-dead patients may improve their comprehension and satisfaction with the provided medical information.

Contrast-Enhanced Transcranial Color Sonography in the Diagnosis of Cerebral Circulatory Arrest

Objective We sought to determine the utility of constrat-enhanced transcranial color sonography (TCCS) in the diagnosis of cerebral circulatory arrest in cases of difficult acoustic window. Materials and Methods From January 2007 to July 2008, we prospectively studied 50 patients who fulfilled clinical criteria of brain death. In all cases, we performed TCCS aiming to insonate both middle cerebral arteries (MCA) and the basilar artery (BA). In those case in which insonation of any vessel was not possible, we repeated the exploration after injecting a 2.5-mL bolus of sulphurhexafluoridedispersion. Afterward, we compared the rate of insonation of the vessels and the number of conclusive studies. Results The mean patient age was 53.2 ± 15.9 years. Thirty-two were men (64%). The most frequent neurologic injury was hemorrhagic stroke and traumatic brain injury. Contrast-enhanced TCCS resulted in an increased rate of insonation in both MCA and in BA, and in the number of conclusive studies. Conclusions Contrast-enhanced TCCS increased the number of conclusive studies with cerebral circulatory arrest, which minimized the importance of a previous study in cases with a poor acoustic window.

149. Diagnosis of cerebral circulatory arrest by Doppler ultrasound in brain death: Do we need the cervical arteries?

149. Diagnosis of cerebral circulatory arrest by Doppler ultrasound in brain death: Do we need the cervical arteries?

Diagnosis of cerebral circulatory arrest by Doppler ultrasound in brain death: Do we need the cervical arteries?

Diagnosis of cerebral circulatory arrest by Doppler ultrasound in brain death: Do we need the cervical arteries?

Significance of the ventricular fluid pressure wave form in the diagnosis of cerebral circulatory arrest and brain death.

The fluctuations in the absolute value of the ventricular fluid pressure (VFP) with simultaneous changes in the amplitude and frequency of the oscillations of the ventricular fluid wave form are described in seven patients who developed brain death following either a head injury or a cerebrovascular accident, and are compared with those observed in nineteen patients who survived similar brain pathology. The findings in the two groups were significantly different. It is suggested that VFP monitoring does provide reliable evidence of brain death even while the patient is on artificial respiration.