MARCELO DE LIMA OLIVEIRA
Projetos de Pesquisa
Unidades Organizacionais
LIM/26 - Laboratório de Pesquisa em Cirurgia Experimental, Hospital das Clínicas, Faculdade de Medicina
9 resultados
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- Role of computed tomography angiography and perfusion tomography in diagnosing brain death: A systematic review(2016) BRASIL, Sergio; BOR-SENG-SHU, Edson; DE-LIMA-OLIVEIRA, Marcelo; AZEVEDO, Milena K.; TEIXEIRA, Manoel J.; BERNARDO, Luca; BERNARDO, Wanderley M.Background: Several complications make the diagnosis of brain death (BD) medically chal-lenging and a complimentary method is needed for confirmation. In this context, computed tomography angiography (CTA) and computed tomography perfusion (CTP) could represent valuable alternatives; however, the reliability of CTA and CTP for confirming brain circulatory arrest remains unclear. Methods: A systematic review was performed to identify relevant studies regarding the use of CTA and CTP as ancillary tests for BD confirmation. Results: Three hundred twenty-two patients were eligible for the meta-analysis, which exhibited 87.5% sensitivity. CTA image evaluation protocol exhibited variations between medical institutions regarding which intracranial vessels should be considered to determine positive or negative test results. Conclusions: For patients who were previously diagnosed with BD according to clinical criteria, CTA demonstrated high sensitivity to provide radiologic confirmation. The current evidence that supports the use of CTA in BD diagnosis is comparable to other methods applied worldwide.
- Cerebral hemodynamic and metabolic changes in fulminant hepatic failure(2017) PASCHOAL JUNIOR, Fernando Mendes; NOGUEIRA, Ricardo de Carvalho; OLIVEIRA, Marcelo de Lima; PASCHOAL, Eric Homero Albuquerque; TEIXEIRA, Manoel Jacobsen; D'ALBUQUERQUE, Luiz Augusto Carneiro; BOR-SENG-SHU, EdsonIntracranial hypertension and brain swelling are a major cause of morbidity and mortality of patients suffering from fulminant hepatic failure (FHF). The pathogenesis of these complications has been investigated in man, in experimental models and in isolated cell systems. Currently, the mechanism underlying cerebral edema and intracranial hypertension in the presence of FHF is multi-factorial in etiology and only partially understood. The aim of this paper is to review the pathophysiology of cerebral hemodynamic and metabolism changes in FHF in order to improve understanding of intracranial dynamics complication in FHF.
- Pathophysiology and Diagnosis of Vertebrobasilar Insufficiency: A Review of the Literature(2017) LIMA NETO, Arlindo Cardoso; BITTAR, Roseli; GATTAS, Gabriel Scarabotolo; BOR-SENG-SHU, Edson; OLIVEIRA, Marcelo de Lima; MONSANTO, Rafael da Costa; BITTAR, Luis FelipeAbstract Introduction Vertebrobasilar insufficiency is defined as transitory ischemia of the vertebrobasilar circulation. Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms. Objective To review the literature regarding the three available diagnostic testing in patients with dizziness complaints secondary to vertebrobasilar insufficiency (VBI): magnetic resonance angiography; transcranial Doppler ultrasound; and vertebrobasilar deprivation testing. Data Synthesis We selected 28 studies that complied with our selection criteria for appraisal. The most frequent cause of the hemodynamic changes leading to VBI is atherosclerosis. The main clinical symptoms are dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body. Even though arteriography is considered the most important exam to diagnose the disease, the inherent risks of this exam should be taken into consideration. The magnetic resonance angiography has been widely studied and is a good method to identify and localize any occlusions and stenosis in both neck and intracranial great vessels. Conclusion Each patient with a suspected diagnosis of VBI should be individually evaluated and treated, taking in consideration the pros and cons of each diagnostic testing and treatment option.
- Cerebral hemodynamics in sepsis assessed by transcranial Doppler: a systematic review and meta-analysis(2017) AZEVEDO, Daniel Silva de; SALINET, Angela Salomao Macedo; OLIVEIRA, Marcelo de Lima; TEIXEIRA, Manoel Jacobsen; BOR-SENG-SHU, Edson; NOGUEIRA, Ricardo de CarvalhoCerebral microcirculation is gradually compromised during sepsis, with significant reductions in the function of capillaries and blood perfusion in small vessels. Transcranial Doppler ultrasound (TCD) has been used to assess cerebral circulation in a typical clinical setting. This study was to systematically review TCD studies, assess their methodological quality, and identify trends that can be associated with the temporal evolution of sepsis and its clinical outcome. A meta-analysis of systematic reviews was conducted according to the PRISMA statement. Articles were searched from 1982 until the conclusion of this review in December 2015. Twelve prospective and observational studies were selected. Evaluations of cerebral blood flow, cerebral autoregulation, and carbon dioxide (CO2) vasoreactivity were summarized. A temporal pattern of the evolution of the illness was found. In early sepsis, the median blood flow velocity (Vm) and pulsatility index (PI) increased, and the cerebral autoregulation (CA) remained unchanged. In contrast, Vm normalization, PI reduction and CA impairment were found in later sepsis (patients with severe sepsis or septic shock). Cerebral haemodynamic is impaired in sepsis. Modifications in cerebral blood flow may be consequence to the endothelial dysfunction of the microvasculature induced by the release of inflammatory mediators. A better understanding of cerebral hemodynamics may improve the clinical management of patients with sepsis and, consequently, improve clinical outcomes.
- Encephalic hemodynamic phases in subarachnoid hemorrhage: how to improve the protective effect in patient prognoses(2015) OLIVEIRA, Marcelo de Lima; AZEVEDO, Daniel Silva de; AZEVEDO, Milena Krajnyk de; NOGUEIRA, Ricardo de Carvalho; TEIXEIRA, Manoel Jacobsen; BOR-SENG-SHU, EdsonSubarachnoid hemorrhage is frequently associated with poor prognoses. Three different hemodynamic phases were identified during subarachnoid hemorrhage: oligemia, hyperemia, and vasospasm. Each phase is associated with brain metabolic changes. In this review, we correlated the hemodynamic phases with brain metabolism and potential treatment options in the hopes of improving patient prognoses.
- Revisiting Retrograde Ventriculosinus Shunt as an Alternative for Treating Hydrocephalus in Children(2017) OLIVEIRA, Matheus Fernandes; TEIXEIRA, Manoel Jacobsen; OLIVEIRA, Marcelo Lima; SHU, Edson Bor Seng; PINTO, Fernando Campos GomesIntroduction Retrograde ventriculosinus shunt (RVSS) is a useful option in the daily routine of neurosurgeons dealing with hydrodynamics. The objective of this manuscript is to review the main data about RVSS. Methods We performed a critical review. The keywords used were hydrocephalus, shunt, venous sinus, ventriculosinus shunt, retrograde ventriculosinus shunt, and sagittal sinus. The search was performed in the Medline (Pubmed) and EMBASE databases. Results Van Canneyt et al (2008) and Pinto et al (2016) performed experimental studies confirming the effectiveness of RVSS. El Shafei et al (1985, 1987, 2001) authors reported several cases treated with efficacy and few complications. Oliveira et al (2015, 2016) compared RVSS and ventriculoperitoneal shunt (VPS) in the treatment of hydrocephalus after myelomeningocele repair in infants, with similar functional results. Oliveira et al (2015, 2016) also described the applicability of RVSS in situations when VPS is not feasible, or when the peritoneum is not useful. Discussion Retrograde ventriculosinus shunt is a safe and more physiological option, which requires the use of less prostheticmaterial. It is feasible and applicable. Especially in children, it generates a normotensive state after shunting, allowing centrifugal head growth, once there is no intracranial hypotension due to overdrainage, which may reflect in long-term better psychomotor development. Conclusions The surgical technique of RVSS is feasible. The clinical results are comparable with those of the VPS.
- Multimodal brain monitoring in fulminant hepatic failure(2016) PASCHOAL JR., Fernando Mendes; NOGUEIRA, Ricardo Carvalho; RONCONI, Karla De Almeida Lins; OLIVEIRA, Marcelo de Lima; TEIXEIRA, Manoel Jacobsen; BOR-SENG-SHU, EdsonAcute liver failure, also known as fulminant hepatic failure (FHF), embraces a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction, and hepatic encephalopathy. Cerebral edema and intracranial hypertension are common causes of mortality in patients with FHF. The management of patients who present acute liver failure starts with determining the cause and an initial evaluation of prognosis. Regardless of whether or not patients are listed for liver transplantation, they should still be monitored for recovery, death, or transplantation. In the past, neuromonitoring was restricted to serial clinical neurologic examination and, in some cases, intracranial pressure monitoring. Over the years, this monitoring has proven insufficient, as brain abnormalities were detected at late and irreversible stages. The need for real-time monitoring of brain functions to favor prompt treatment and avert irreversible brain injuries led to the concepts of multimodal monitoring and neurophysiological decision support. New monitoring techniques, such as brain tissue oxygen tension, continuous electroencephalogram, transcranial Doppler, and cerebral microdialysis, have been developed. These techniques enable early diagnosis of brain hemodynamic, electrical, and biochemical changes, allow brain anatomical and physiological monitoring-guided therapy, and have improved patient survival rates. The purpose of this review is to discuss the multimodality methods available for monitoring patients with FHF in the neurocritical care setting.
- Transcranial brain sonography for Parkinsonian syndromes(2019) BOR-SENG-SHU, Edson; PASCHOAL, Fernando M.; ALMEIDA, Kelson J.; OLIVEIRA, Marcelo De Lima; NOGUEIRA, Ricardo C.; TEIXEIRA, Manoel J.; WALTER, UweSubstantia nigra (SN) hyperechogenicity has been proved to be a characteristic finding for idiopathic Parkinson's disease (PD), occurring in more than 90% of the patients. This echofeature is owed to increased amounts of iron in the SN region and reflects a functional impairment of the nigrostriatal dopaminergic system. In a prospective blinded study in which a group of patients with early mild signs and symptoms of unclear Parkinsonism were followed until a definite clinical diagnosis of PD, the hyperechogenicity of the SN was demonstrated to be highly predictive of a final diagnosis of PD. For the diagnosis of PD in individuals with early motor symptoms, both the sensitivity and positive predictive value of SN hyperechogenicity were higher than 90% and both the specificity and negative predictive value were higher than 80%. For early differential diagnosis between PD and atypical Parkinsonian syndromes, the sensitivity and positive predictive value of SN hyperechogenicity were higher than 90%, and both the specificity and negative predictive value were higher than 80%. The diagnostic specificity is increased if combining the TCS findings of SN, lenticular nucleus and third ventricle. In asymptomatic adult subjects, SN hyperechogenicity, at least unilaterally, indicates a subclinical functional insufficiency of the nigrostriatal dopaminergic system. Recent papers revealed that SN hyperechogenicity might suggest preclinical PD. Reduced echogenicity of midbrain raphe indicates increased risk of depression in PD patients. Caudate nucleus hyperechogenicity has been associated with drug-induced psychosis, and frontal horn dilatation > 20 mm with dementia. Transcranial brain sonography can be a valuable tool for managing patients with Parkinsonian signs and symptoms.
- Intracranial Hypertension and Cerebral Autoregulation: A Systematic Review and Meta-Analysis(2018) DE-LIMA-OLIVEIRA, Marcelo; SALINET, Angela S. M.; NOGUEIRA, Ricardo C.; AZEVEDO, Daniel S. de; PAIVA, Wellingson S.; TEIXEIRA, Manoel J.; BOR-SENG-SHU, EdsonOBJECTIVE: To present a systematic review and meta-analysis to establish the relation between cerebral autoregulation (CA) and intracranial hypertension. METHODS: An electronic search using the term ""Cerebral autoregulation and intracranial hypertension"" was designed to identify studies that analyzed cerebral blood flow autoregulation in patients undergoing intracranial pressure (ICP) monitoring. The data were used in meta-analyses and sensitivity analyses. RESULTS: A static CA technique was applied in 10 studies (26.3%), a dynamic technique was applied in 25 studies (65.8%), and both techniques were used in 3 studies (7.9%). Static CA studies using the cerebral blood flow technique revealed impaired CA in patients with an ICP >= 20 (standardized mean difference [SMD] 5.44%, 95% confidence interval [CI] 0.25-10.65, P = 0.04); static CA studies with transcranial Doppler revealed a tendency toward impaired CA in patients with ICP >= 20 (SMD -7.83%, 95% CI -17.52 to 1.85, P = 0.11). Moving correlation studies reported impaired CA in patients with ICP >= 20 (SMD 0.06, 95% CI 0.07-0.14, P < 0.00001). A comparison of CA values and mean ICP revealed a correlation between greater ICP and impaired CA (SMD 5.47, 95% CI 1.39-10.1, P = 0.01). Patients with ICP >= 20 had an elevated risk of impaired CA (OR 2.27, 95% CI 1.20-4.31, P = 0.01). CONCLUSIONS: A clear tendency toward CA impairment was observed in patients with increased ICP.