DALTON MARQUES CHAVES

(Fonte: Lattes)
Índice h a partir de 2011
14
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico

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Agora exibindo 1 - 10 de 12
  • conferenceObject
    Gastric PerOral Endoscopic Myotomy (G-POEM) for Refractory Gastroparesis: Results From the First Multicenter Study on Endoscopic Pyloromyotomy
    (2016) KHASHAB, Mouen A.; NGAMRUENGPHONG, Saowanee; CARR-LOCKE, David L.; BAPAYE, Amol; BENIAS, Petros C.; SEROUYA, Sam; DUBALE, Nachiket; CHAVES, Dalton M.; ARTIFON, Everson L.; KUMBHARI, Vivek; CHAVEZ, Yamile Haito; BUKHARI, Majidah; HAJIYEVA, Gulara; ISMAIL, Amr; CHEN, Yen-I.; MOURA, Eduardo G. de; CHUNG, Hyunsoo
  • article 11 Citação(ões) na Scopus
    Suction versus slow-pull for endoscopic ultrasound-guided fine-needle aspiration of pancreatic tumors: a prospective randomized trial
    (2020) CHENG, Spencer; BRUNALDI, Vitor O.; MINATA, Mauricio K.; CHACON, Danielle A.; SILVEIRA, Eduardo B.; MOURA, Diogo T. H. de; SANTOS, Marcos E. L. Dos; MATUGUMA, Sergio E.; CHAVES, Dalton M.; FRANCA, Raony F.; JACOMO, Alfredo L.; ARTIFON, Everson L. A.
    Background: Suction (S) is commonly used to improve cell acquisition during endoscopic ultrasoundguided fine-needle aspiration (EUS-FNA). Slow-pull (SP) sampling is another technique that might procure good quality specimens with less bloodiness. We aimed to determine if SP improves the diagnostic yield of EUS-FNA of pancreatic masses. Methods: Patients with pancreatic solid masses were randomized to four needle passes with both techniques in an alternate fashion. Sensitivity, specificity, positive, and negative predictive values were calculated. Cellularity and bloodiness of cytological samples were assessed and compared according to the technique. Results: Sensitivity, specificity, and accuracy of suction vs. SP were 95.2% vs. 92.3%; 100% vs. 100; 95.7% vs. 93%, respectively. As to the association of methods, they were 95.6, 100 and 96%, respectively. Positive predictive values for S and SP were 100%. There was no difference in diagnostic yield between S and SP (p = 0.344). Cellularity of samples obtained with SP and Suction were equivalent in both smear evaluation (p = 0.119) and cell-block (0.980). Bloodiness of SP and suction techniques were similar as well. Conclusions: S and SP techniques provide equivalent sensitivity, specificity, and accuracy. Association of methods seems to improve diagnostic yield. Suction does not increase the bloodiness of samples compared to slow-pull.
  • conferenceObject
    Endoscopic Papillary Large Balloon Dilation Associated With Sphincterotomy for Extraction of Large Bile Duct Stones
    (2012) LUZ, Gustavo O.; MOURA, Eduardo G. De; MEINE, Gilmara C.; CARNEIRO, Fred O.; MEDRADO, Bruno F.; ALMEIDA, Maira R.; MALUF-FILHO, Fauze; LERA, Marcos; IDE, Edson; FURUYA, Carlos K.; CHAVES, Dalton M.; CHENG, Spencer; MATUGUMA, Sergio E.; TOMISHIGE, Toshiro; HONDO, Fabio Y.; BARACAT, Renato; ARTIFON, Everson L.; FRANZINI, Tomazo; SAKAI, Paulo
    Common bile duct stones larger than 15mm are related to a higher rate of failure of endoscopic ductal clearance and need for mechanical lithotripsy. Recently, endoscopic papillary large balloon dilation (EPLBD) associated with endoscopic sphyncterotomy (ES) has been advocated for the management of difficult bile duct stones. Objective: Evaluate the efficacy and safety of EPLBD associated with ES for removal of large bile duct stones. Patients and methods: retrospective review of prospectively collected data in an academic tertiary referral center, from November 2009 to August 2011. Ampullary dilation was performed with a wire guided hydrostatic balloon (CRE/Boston Scientific) which size ranged from 12 to 20mm. The stone size and the duct diameter directed the choice of the balloon diameter. Balloon was inflated with diluted contrast medium under endoscopic and fluoroscopic control until waist disappearance and/or maximal balloon pressure. After dilation stones were extracted with the aid of standard accessories and techniques. Outcomes and adverse events were recorded. Results: A total of 730 patients with common bile duct stones were admitted for ERCP in our institution. 123 (16,8%) patients were submitted to EPLBD after sphincterotomy. The mean age was 56 years (22-98) and 77 were female (63%). The size of the stones ranged from 13 to 30mm. Initial procedure success rate without mechanical lithitripsy was 83% (102/123). In further 4 patients (3,2%) mechanical lithotripsy was used with 75% success rate (3/4). For the remaining 17 patients, mechanical litotripsy was not available and a 10Fr biliary stent was introduced to prevent obstruction and cholangitis. The total adverse events rate was 3,2%. There were 2 cases of perforation with 20mm balloon (1,6%), both treated conservatively, and two cases of mild acute pancreatitis (1,6%). None of the patients presented bleeding that required transfusion or hospitalization. Conclusion: EPLBD after sphincterotomy is a safe and effective technique for the management of large bile duct stones and it avoids mechanical lithotripsy in the majority of cases.
  • article 38 Citação(ões) na Scopus
    Endoscopic pyloromyotomy via a gastric submucosal tunnel dissection for the treatment of gastroparesis after surgical vagal lesion
    (2014) CHAVES, Dalton M.; MOURA, Eduardo G. H. de; MESTIERI, Luiz H. M.; ARTIFON, Everson L.; SAKAI, Paulo
  • article 149 Citação(ões) na Scopus
    Gastric per-oral endoscopic myotomy for refractory gastroparesis: results from the first multicenter study on endoscopic pyloromyotomy (with video)
    (2017) KHASHAB, Mouen A.; NGAMRUENGPHONG, Saowanee; CARR-LOCKE, David; BAPAYE, Amol; BENIAS, Petros C.; SEROUYA, Sam; DORWAT, Shivangi; CHAVES, Dalton M.; ARTIFON, Everson; MOURA, Eduardo G. de; KUMBHARI, Vivek; CHAVEZ, Yamile Haito; BUKHARI, Majidah; HAJIYEVA, Gulara; ISMAIL, Amr; CHEN, Yen-I.; CHUNG, Hyunsoo
    Background and Aims: Gastric per-oral endoscopic myotomy (G-POEM) recently has been reported as minimally invasive therapy for gastroparesis. The aims of this study were to report on the first multicenter experience with G-POEM and to assess the efficacy and safety of this novel procedure for patients with gastroparesis with symptoms refractory to medical therapy. Methods: All patients with gastroparesis who underwent endoscopic pyloromyotomy (G-POEM) at 5 medical centers were included. Procedures were performed following the same principles as esophageal POEM. Clinical response was defined as improvement in gastroparetic symptoms with absence of recurrent hospitalization. Adverse events were graded according to the American Society for Gastrointestinal Endoscopy lexicon. Results: A total of 30 patients with refractory gastroparesis (11 diabetic, 12 postsurgical, 7 idiopathic) underwent G-POEM. Previous therapies included Botox injection in 12, transpyloric stenting in 3, and PEG with jejunal extension (PEGJ) in 1. Nausea/vomiting were the predominant symptoms in 25 patients. Weight loss was present in 27 patients with an average of 10% loss of body weight. G-POEM was completed successfully in all 30 (100%) patients with a mean procedure time of 72 minutes (range, 35-223 min). The mean myotomy length was 2.6 +/- 2.3 cm. The mean length of hospital stay was 3.3 days (range, 1-12 days). Two adverse events occurred in 2 (6.7%) patients, including 1 capnoperitoneum and 1 prepyloric ulcer, rated as mild and severe, respectively. Clinical response was observed in 26 (86%) patients during a median follow-up of 5.5 months. Four patients (2 diabetic, 1 postsurgical, 1 idiopathic cause) did not respond to G-POEM. Repeat gastric emptying scan was obtained in 17 patients, normalized in 8 (47%), and improved in 6 (35%) patients. Conclusion: G-POEM is a technically feasible procedure. This small non-randomized study suggests the effectiveness of G-POEM for the treatment of patients with gastroparesis refractory to medical therapy. It concomitantly results in normalization of GES in a significant proportion of treated patients.
  • article 28 Citação(ões) na Scopus
    Endoscopic ultrasound versus magnetic resonance cholangiopancreatogrphy in suspected choledocholithiasis: A systematic review
    (2016) CASTRO, Vinicius Leite De; MOURA, Eduardo G. H.; CHAVES, Dalton M.; BERNARDO, Wanderley M.; MATUGUMA, Sergio E.; ARTIFON, Everson L. A.
    Background and Objectives: There is a lack of consensus about the optimal noninvasive strategy for patients with suspected choledocholithiasis. Two previous systematic reviews used different methodologies not based on pretest probabilities that demonstrated no statistically significant difference between Endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP) for the detection of choledocholithiasis. In this article, we made a comparison of the diagnostic ability of EUS and MRCP to detect choledocholithiasis in suspected patients. Methods: We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations with all published randomized prospective trials. We performed the systemic review using MedLine, EMBASE, Cochrane, LILACS, and Scopus reviews through May 2015. We identified eight randomized, prospective, blinded trials comparing EUS and MRCP. All the patients were submitted to a gold standard method. We calculated the study-specific variables and performed analyses using aggregated variables such as sensitivity, specificity, prevalence, positive predictive value (PPV) and negative predictive value (NPV), and accuracy. Results: Five hundred and thirty eight patients were included in the analysis. The pretest probability for choledocholithiasis was 38.7. The mean sensitivity of EUS and MRCP for detection of choledocholithiasis was 93.7 and 83.5, respectively; the specificity was 88.5 and 91.5, respectively. Regarding EUS and MRCP, PPV was 89 and 87.8, respectively, and NPV was 96.9 and 87.8, respectively. The accuracy of EUS and MRCP was 93.3 and 89.7, respectively. Conclusions: For the same pretest probability of choledocholithiasis, EUS has higher posttest probability when the result is positive and a lower posttest probability when the result is negative compared with MRCP.
  • conferenceObject
    Endoscopic Ultrasound Evaluation After Endoscopic Eradication of Esophageal Varices With Band Ligation: Does It Predict Variceal Recurrence?
    (2016) CARNEIRO, Fred O.; RETES, Felipe A.; MATUGUMA, Sergio E.; ALBERS, Debora V.; CHAVES, Dalton M.; SANTOS, Marcos E.; HERMAN, Paulo; CHAIB, Eleazar; SAKAI, Paulo; ALBUQUERQUE, Luiz C. D.; MALUF-FILHO, Fauze
  • conferenceObject
    Deep Sedation Events During Diagnostic Upper Gastrointestinal Endoscopy: A Randomized Study of the Regimens Propofol-Fentanyl and Midazolam-Fentanyl
    (2012) SANTOS, Marcos E. Lera Dos; MOURA, Eduardo G. De; SAKAI, Paulo; MATUGUMA, Sergio E.; IDE, Edson; CHAVES, Dalton M.; LUZ, Gustavo; SOUZA, Thiago F.; PESSORRUSSO, Fernanda C.; MESTIERI, Luiz H.; MALUF-FILHO, Fauze
    Gastrointestinal Endoscopy Unit - Gastroenterology Department, University of Sao Paulo Medical School, Sao Paulo, Brazil Background and Study Aims: For upper gastrointestinal endoscopy (UGIE), the use of sedation is nearly universal. The objective of this study was to compare two drug combinations in terms of the frequency of deep sedation events during UGIE. Patients and Methods: We evaluated 200 patients referred for UGIE. Patients were randomized to receive propofol-fentanyl or midazolam-fentanyl (n = 100/group). We assessed the level of sedation with the Observer’s Assessment of Alertness/Sedation (OAA/S) and the bispectral index (BIS). We evaluated patient and physician satisfaction, as well as recovery time and complication rates. Results: The times to induction sedation, recovery, and discharge were shorter in the propofol-fentanyl group than in the midazolam-fentanyl group. According to the OAA/S, deep sedation events occurred in 25% of the propofol-fentanyl group patients and 11% of the midazolam-fentanyl group patients (p = 0.014), compared with 19% and 7%, respectively, for the BIS (p = 0.039). There was good concordance between the OAA/S and the BIS for both groups (k = 0.71 and k = 0.63, respectively). Oxygen supplementation was required in 42% of the propofol-fentanyl group patients and in 26% of the midazolam-fentanyl group patients (p = 0.025). The mean time to recovery was 28.82 and 44.13 min in the propofol-fentanyl and midazolam-fentanyl groups, respectively (p < 0.001). There were no severe complications in either group. Although patients were equally satisfied with both drug combinations, physicians were more satisfied with the propofol-fentanyl combination. Conclusions: Despite the greater risk of deep sedation, propofol is preferable to midazolam.
  • article 11 Citação(ões) na Scopus
    A New Technique for Performing Endoscopic Pyloromyotomy by Gastric Submucosal Tunnel Dissection
    (2014) CHAVES, Dalton M.; GUSMON, Carla C.; MESTIERI, Luiz H. M.; MOURA, Eduardo G. H. de; VERAS, Mariana M.; PESSORRUSSO, Fernanda C. S.; SAKAI, Paulo
    Aim:To investigate the feasibility of a new endoscopic pyloromyotomy technique. Materials and Methods:Endoscopic pyloromyotomy through a gastric submucosal tunnel was performed in 6 pigs. At the greater curvature, 2 cm proximal to the pylorus, we incised the mucosa and dissected the submucosal tunnel up to the pyloric ring. The pyloric muscular ring was sectioned, and then the gastric mucosal incision was closed with metallic clips. The pigs were then euthanized and necropsies were performed. Results:Section of the pyloric ring was successful in all 6 pigs. Small perforations occurred in 2 of the pigs, and there was limited bleeding in 1 pig. Necropsy and histologic evaluation confirmed the pyloric section. Conclusions:This technique is feasible, easy to perform, and maybe alternative to pyloroplasty in selected cases. Experimental comparative studies with other techniques still must be performed.
  • conferenceObject
    Learning Curve for ESD: Experience From a South American Center
    (2012) MOURA, Eduardo G. H. De; YAMAZAKI, Kendi; MESTIERI, Luiz H.; MIYAJIMA, Nelson T.; CHAVES, Dalton M.; SANTOS, Marcos E. Lera Dos; IDE, Edson; FRANZINI, Tomazo; PESSORRUSSO, Fernanda C.; SAKAI, Paulo
    Introduction: Endoscopic resection techniques such as endoscopic submucosal dissection (ESD) for early gastric cancer are gaining acceptance in many countries. However complication rates on this procedure reaches 20% on non-experienced hands. Experts recommend that ESD should first be carried out in animal models before starting to be performed in humans, in order to overcome the initial learning curve. Aims: To evaluate the learning curve during intensive ESD training on live porcine models under supervision of experts. Material and Methods: Forty endoscopists have performed ESD during an intensive training course on live porcine models, under experts’ supervision. This training had duration of two days. Simulation of a gastric lesion was obtained by aspirating the gastric mucosa with a cap on the tip of the endoscope. The following variables were analyzed: procedure time, resected specimen size, complete en bloc resection rate, circumferential incision time, submucosal solution injected volume, distance between the circumferential incision and the lesion (lateral margin) and complication rates as perforation, bleeding and death. And from the beginning to the end of the last procedure a questionnaire was given to the participants to see if they felt secure to perform ESD without supervision. Results: At the end of 2 days training, 125 gastric ESDs were achieved. Each participant performed at least 3 complete ESDs. The mean procedure time for the first cases were 32.69 min ± 15.89 (CI 95% 6.52 - 19.36) and at the end of the third case 19.7min ± 8.57 (CI 95% 6.52 - 19.36), p 0.001; the distance between the circumferential incision and the lesion (lateral margin) has increased from 2.54mm 1.75 (CI 95% 1.24 - 1.05) to 2.71mm ± 2.70(CI 95% 1.24 - 1.05), p=0.87 at the end of the third case. Bleeding rate has decreased from 18.75% to 15.63%. At the end of the training course 56.25% of the endoscopists felt secure to do ESD without supervision, a percentage that was 6.25% at the beginning of the course. Conclusion: Training ESD on live porcine models may help endoscopist overcome the learning curve but more training is needed to make it secure in humans.