MARCELO DE LIMA OLIVEIRA
Projetos de Pesquisa
Unidades Organizacionais
LIM/26 - Laboratório de Pesquisa em Cirurgia Experimental, Hospital das Clínicas, Faculdade de Medicina
61 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 61
conferenceObject Cerebral compliance assessment using Trancranial Doppler(2018) BRASIL, S.; BOR-SENG-SHU, E.; DE-LIMA-OLIVEIRA, M.; NOGUEIRA, R.; SALINET, A.; PAIVA, W.; TEIXEIRA, M.- Intraoperative Ultrasound in Chiari Type I Malformation(2020) BROCK, R. S.; TARICCO, M. A.; OLIVEIRA, M. F. De; OLIVEIRA, M. De Lima; TEIXEIRA, M. J.; BOR-SENG-SHU, E.The advent of intraoperative ultrasonography (USG) has allowed identification of craniocervical junction (CVJ) anatomy and cerebrospinal fluid dynamics and CVJ structures with real-time images. It is possible to use intraoperative USG in patients with Chiari malformation type I as a method for selection of candidates for posterior fossa decompression with bone removal alone. This chapter describes the authors’ experience using intraoperative USG. © Springer Nature Switzerland AG 2020.
- 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.
- Transcranial Doppler: A Useful Tool to Predict Brain Death Still Not Confirmed by Clinical Assessment(2021) RONCONI, Karla de Almeida Lins; AMORIM, Robson Luis Oliveira de; JR, Fernando Mendes Paschoal; OLIVEIRA, Marcelo de Lima; NOGUEIRA, Ricardo de Carvalho; PAIVA, Wellingson Silva; GONCALVES, Daniel Buzaglo; FARIAS, Stephanie Ramos de; BRASIL, Sergio Paulo; TEIXEIRA, Manoel Jacobsen; BOR-SENG-SHU, EdsonBackground. Diagnosing brain death (BD) with accuracy and urgency is of great importance because an early diagnosis may guide the clinical management, optimize hospital beds, and facilitate organ transplantation. The clinical diagnosis of nonreactive and irreversible coma can be confirmed with additional tests. Among the complimentary exams that may testify brain circulatory arrest, transcranial Doppler (TCD) can be an option. It is a real-time, bedside, inexpensive, noninvasive method that assesses cerebral blood flow. In patients with suspected BD, especially those who are under sedative drugs, early diagnosis is imperative. The aim of the present study was to evaluate the role of TCD in predicting BD. Methods. One hundred consecutive comatose patients with a Glasgow Coma Scale score of less than 5, owing to different etiologies, were included. TCD was performed in all patients. The TCD operator was blinded for clinical and neurologic data. This study is in compliance with the Declaration of Helsinki. Results. Sixty-nine patients with TCD-brain circulatory collapse were diagnosed later with BD. Of the 31 patients with brain circulatory activity, 8 (25.8%) were clinically brain dead and 23 (74.2%) were alive. TCD showing brain circulatory collapse had a sensitivity of 89.6%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 74.2%. Conclusion. TCD is highly specific (100%) and sensitive (89.6%) as a method to confirm the clinical diagnosis of BD, even in patients under sedation. The possibility of patients presenting with cerebral circulatory activity and clinical diagnosis of BD was demonstrated to occur.
conferenceObject Subclinical Coronary Atherosclerosis in Subjects with Ischemic Stroke caused by Cervicocephalic Atherothrombosis - preliminary results(2018) ARAUJO, Ana Luiza; NOMURA, Cesar; SANTOS, Raul; SHU, Edson; OLIVEIRA, Marcelo; MARTIN, Maria; OSHIRO, Carlos; MIRANDA, Maramelia; SILVA, Gisele Sampaio; SILVA, Victor; LEITE, Claudia; CONFORTO, Adriana- Cerebral hemodynamics with intra-aortic balloon pump: business as usual?(2017) CALDAS, J. R.; PANERAI, R. B.; BOR-SENG-SHU, E.; ALMEIDA, J. P.; FERREIRA, G. S. R.; CAMARA, L.; NOGUEIRA, R. C.; OLIVEIRA, M. L.; JATENE, F. B.; ROBINSON, T. G.; HAJJAR, L. A.Objective: Intra-aortic balloon pump (IABP) is commonly used as mechanical support after cardiac surgery or cardiac shock. Although its benefits for cardiac function have been well documented, its effects on cerebral circulation are still controversial. We hypothesized that transfer function analysis (TFA) and continuous estimates of dynamic cerebral autoregulation (CA) provide consistent results in the assessment of cerebral autoregulation in patients with IABP. Approach: Continuous recordings of blood pressure (BP, intra-arterial line), end-tidal CO2, heart rate and cerebral blood flow velocity (CBFV, transcranial Doppler) were obtained (i) 5 min with IABP ratio 1: 3, (ii) 5 min, starting 1 min with the IABP-ON, and continuing for another 4 min without pump assistance (IABP-OFF). Autoregulation index (ARI) was estimated from the CBFV response to a step change in BP derived by TFA and as a function of time using an autoregressive moving-average model during removal of the device (ARI(t)). Critical closing pressure and resistance area-product were also obtained. Main results: ARI with IABP-ON (4.3 +/- 1.2) were not different from corresponding values at IABP-OFF (4.7 +/- 1.4, p = 0.42). Removal of the balloon had no effect on ARIt, CBFV, BP, cerebral critical closing pressure or resistance area-product. Significance: IABP does not disturb cerebral hemodynamics. TFA and continuous estimates of dynamic CA can be used to assess cerebral hemodynamics in patients with IABP. These findings have important implications for the design of studies of critically ill patients requiring the use of different invasive support devices.
- TCD assessment in fulminant hepatic failure: Improvements in cerebral autoregulation after liver transplantation(2024) PASCHOAL-JR, Fernando M.; NOGUEIRA, Ricardo C.; RONCONI, Karla de Almeida Lins; OLIVEIRA, Marcelo de Lima; ALMEIDA, Kelson James; ROCHA, Ivana Schmidtbauer; PASCHOAL, Eric Homero Albuquerque; PASCHOAL, Joelma Karin Sagica Fernandes; D'ALBUQUERQUE, Luiz Augusto Carneiro; TEIXEIRA, Manoel Jacobsen; PANERAI, Ronney B.; BOR-SENG-SHU, EdsonIntroduction and Objectives: Acute liver failure, also known as fulminant hepatic failure (FHF), includes a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction and hepatic encephalopathy. The objective of this study was to assess cerebral autoregulation (CA) in 25 patients (19 female) with FHF and to follow up seventeen of these patients before and after liver transplantation.Patients and Methods: The mean age was 33.8 years (range 14-56, SD 13.1 years). Cerebral hemodynamics was assessed by transcranial Doppler (TCD) bilateral recordings of cerebral blood velocity (CBv) in the middle cerebral arteries (MCA).Results: CA was assessed based on the static CA index (SCAI), reflecting the effects of a 20-30 mmHg increase in mean arterial blood pressure on CBv induced with norepinephrine infusion. SCAI was estimated at four time points: pretransplant and on the 1st, 2nd and 3rd posttransplant days showing a significant difference between pre-and posttransplant SCAI (p = 0.005). SCAI peaked on the third posttransplant day (p = 0.006). Categorical analysis of SCAI showed that for most patients, CA was reestablished on the second day post-transplant (SCAI > 0.6).Conclusions: These results suggest that CA impairment pretransplant and on the 1st day posttransplant was re-established at 48-72 h after transplantation. These findings can help to improve the management of this patient group during these specific phases, thereby avoiding neurological complications, such as brain swelling and intracranial hypertension.(c) 2023 Fundacion Clinica Medica Sur, A.C.
- Dynamic cerebral autoregulation: A marker of post-operative delirium?(2019) CALDAS, Juliana R.; PANERAI, Ronney B.; BOR-SENG-SHU, Edson; FERREIRA, Graziela S. R.; CAMARA, Ligia; PASSOS, R. H.; DE-LIMA-OLIVEIRA, Marcelo; GALAS, Filomena R. B. G.; ALMEIDA, Juliano P.; NOGUEIRA, Ricardo C.; MIAN, Natalia; GAIOTTO, Fabio A.; ROBINSON, Thompson G.; HAJJAR, Ludhmila A.Objective: We investigated the potential association of cerebral autoregulation (CA) with postoperative delirium (PD), a common complication of cardiac surgery with cardiopulmonary bypass (CPB). Methods: In patients undergoing coronary artery bypass graft (CABG) surgery with CPB, cerebral blood flow velocity (CBFV) and blood pressure (BP) were continuously recorded during 5-min preoperatively (T1), after 24 h (T2), and 7 days after procedure (T3). Prospective multivariate logistic regression analysis was performed to determine the independent risk factors of PD. Autoregulation index (ARI) was calculated from the CBFV response to a step change in BP derived by transfer function analysis. Results: In 67 patients, mean age 64.3 +/- 9.5 years, CA was depressed at T2 as shown by values of ARI (3.9 +/- 1.7), compared to T1 (5.6 +/- 1.7) and T3 (5.5 +/- 1.8) (p < 0.001). Impaired CA was found in 37 (55%) patients at T2 and in 7 patients (20%) at T3. Lower ARI at T1 and T2 were predictors of PD (p = 0.003). Conclusion: Dynamic CA was impaired after CABG surgery with CPB and was a significant independent risk factor of PD. Significance: Assessment of CA before and after surgery could have considerable potential for early identification of patients at risk of PD, thus reducing poor outcomes and length of stay.
- 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.
- Mortality, Morbidity, and Prognostic Factors in the Surgical Resection of Brain Metastases: A Contemporary Cohort Study(2020) PICARELLI, Helder; OLIVEIRA, Marcelo de Lima; MARTA, Gustavo Nader; SOLLA, Davi J. Fontoura; TEIXEIRA, Manoel Jacobsen; FIGUEIREDO, Eberval GadelhaObjective Despite advances in systemic therapy and radiotherapy (RT), neurosurgical resection (NSR) remains a mainstay of the treatment of brain metastases (BMs). Although it is unequivocal in instances of diagnostic doubt, radioresistance, and risk of death due to neurologic causes, NSR may be controversial in other situations. Many aspects related to NSR have not yet been well established, and the primary prognostic indices were proposed only in the last decade. This study evaluates the survival and the morbidity, causes of death, prognostic factors, and the impact of RT in patients with BMs treated by NSR in the current era. Methods A total of 200 patients with BMs who were treated by NSR were evaluated sequentially and followed prospectively. We used logistic regression and Cox regression models to identify independent factors associated with mortality at 4 weeks and at 1 year, respectively. Clinical features, morbidity, recurrence, and causes of death were also studied. Results Lung cancer was the most prevalent cancer (36.5%); the median Karnofsky Performance Status (KPS) score was 60. Total resection was achieved in 89%, and adjuvant RT was applied in 63% of the cases. The rates of surgical mortality, morbidity, and mortality at 4 weeks were 1.5%, 17%, and 7.5%, respectively. Systemic infections were the leading cause of death in 62.5% of the cases. The median survival was 5 months, and 34.5% of patients lived > 1 year. The postoperative KPS (KPSpo) score remained unchanged or improved in 94.5% of the cases. In the multivariate analysis, a KPSpo score >= 80 and the application of adjuvant RT were associated with a lower risk of death at 12 weeks and at 1 year. Interestingly, the variables of primary tumor site, number of BMs, and presence of carcinomatous meningitis were not significant. Conclusion Morbidity and mortality were high, a third of the patients lived > 1 year, and the KPS score improved or remained unchanged in most cases. Prognostic indices and health conditions were important predictive factors, but the KPSpo score and adjuvant RT were independent variables for survival at 12 weeks and at 1 year. Therefore, new studies are needed to assess the influence of new therapies and specific molecular profiles.