MARIA MERCES SANTOS
Projetos de Pesquisa
Unidades Organizacionais
Instituto da Criança, Hospital das Clínicas, Faculdade de Medicina
LIM/30 - Laboratório de Investigação em Cirurgia Pediát, Hospital das Clínicas, Faculdade de Medicina
LIM/30 - Laboratório de Investigação em Cirurgia Pediát, Hospital das Clínicas, Faculdade de Medicina
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- Living donor liver transplantation in children: Should the adult donor be operated on by an adult or pediatric surgeon? Experience of a single pediatric center(2014) ANDRADE, Wagner de Castro; VELHOTE, Manoel Carlos Prieto; AYOUB, Ali Ahman; SILVA, Marcos Marques; GIBELLI, Nelson Elias M.; TANNURI, Ana Cristina A.; SANTOS, Maria Merces; PINHO-APEZZATO, Maria Lucia; BARROS, Fabio de; MOREIRA, Daniel Rangel; MIYATANI, Helena T.; PEREIRA, Raimundo Renato; TANNURI, UenisBackground/Purpose: Living donor liver transplantation has become a cornerstone for the treatment of children with end-stage hepatic dysfunction, especially within populations or countries with low rates of organ utilization from deceased donors. The objective is to report our experience with 185 living donors operated on by a team pediatric surgeons in a tertiary center for pediatric liver transplantation. Methods: Retrospective analysis of medical records of donors of hepatic grafts for transplant undergoing surgery between June 1998 and March 2013. Results: Over the last 14 years, 185 liver transplants were performed in pediatric recipients of grafts from living donors. Among the donors, 166 left lateral segments (89.7%), 18 left lobes without the caudate lobe (9.7%) and 1 right lobe (0.5%) were harvested. The donor age ranged from 16 to 53 years, and the weight ranged from 47 to 106 kg. In 10 donors, an additional graft of the donor inferior mesenteric vein was harvested to substitute for a hypoplastic recipient portal vein. The transfusion of blood products was required in 15 donors (8.1%). The mean hospital stay was 5 days. No deaths occurred, but complications were identified in 23 patients (12.4%): 9 patients experienced abdominal pain and severe gastrointestinal symptoms and 3 patients required reoperations. Eight donors presented with minor bile leaks that were treated conservatively, and 3 patients developed extra-peritoneal infections (1 wound collection, 1 phlebitis and 1 pneumonia). Eight grafts (4.3%) showed primary dysfunction resulting in recipient death (3 cases of fulminant hepatitis, 1 patient with metabolic disease, 1 patient with Alagille syndrome and 3 cases of biliary atresia in infants under 1 year old). There was no relation between donor complications and primary graft dysfunction (P = 0.6). Conclusions: Living donor transplantation is safe for the donor and presents a low morbidity. The donor surgery may be performed by a team of trained pediatric surgeons.
- Pediatric acute liver failure in Brazil: Is living donor liver transplantation the best choice for treatment?(2016) TANNURI, Ana Cristina Aoun; PORTA, Gilda; MIURA, Irene Kazue; SANTOS, Maria Merces; MOREIRA, Daniel de Albuquerque Rangel; REZENDE, Nathassia Mancebo Avila de; MIYATANI, Helena Thie; TANNURI, UenisAcute liver failure (ALF) in children is a life-threatening condition that often leads to urgent liver transplantation (LT). The aim of the present investigation was to describe the experience in Brazil in treating pediatric ALF, with an emphasis on the role of living donor liver transplantation (LDLT) in treating this condition. All children with ALF who fulfilled the criteria for an urgent LT were admitted to the intensive care unit. Patients were divided into 2 groups based on the moment of admission: before and after June 2007, when the LDLT program for ALF was started. Statistical analyses were performed to identify prognostic factors of patients with ALF. For the study, 115 children with ALF were admitted. All patients had some degree of encephalopathy. Among the patients, 26% of them required intracranial pressure monitoring (IPM), 12.8% of the patients required hemodialysis, and 79 patients underwent transplantation (50 deceased donors and 29 living donors) corresponding to 12.4% of all pediatric LTs. Only 9 children recovered without LT. The need for IPM and nonperformance of LT were related to a higher mortality. The mortality rate of patients who underwent LT was significantly lower than that of children with ALF who did not undergo a LT (48.1% versus 75%; P = 0.02). The incidences of primary nonfunction and mortality were statistically higher among deceased donor liver transplantations than LDLTs. Finally, it was verified that the overall survival rate of transplanted patients was increased after the introduction of LDLT (P = 0.02). In conclusion, ALF in children continues to be a severe and devastating condition, and a LT should be performed promptly. The introduction of LDLT could increase the survival rate of patients in Brazil. Liver Transplantation 22 1006-1013 2016 AASLD
- Living Related Donor Liver Transplantation in Children(2011) TANNURI, A. C. A.; GIBELLI, N. E. M.; RICARDI, L. R. S.; SANTOS, M. M.; MAKSOUD-FILHO, J. G.; PINHO-APEZZATO, M. L.; SILVA, M. M.; VELHOTE, M. C. P.; AYOUB, A. A. R.; ANDRADE, W. C.; LEAL, A. J.; MIYATANI, H. T.; TANNURI, U.Objective. The objective of this study was to report our experience with pediatric orthotopic liver transplantation (OLT) with living related donors. Methods. We performed a retrospective chart analysis of 121 living related donor liver transplantations (LRDLT) from June 1998 to June 2010. Results. Indications were biliary atresia (BA; n = 81), primary sclerosing cholangitis (n = 5), alpha-1 antitrypsin deficiency (n = 4); cholestasis (n = 9), fulminant hepatic failure (n = 8), autoimmune hepatitis (n = 2), Alagille syndrome (n = 4), hepatoblastoma (n = 3), tyrosinemia (n = 2), and congenital hepatic fibrosis (n = 3). The age of the recipients ranged from 7-174 months (median, 22) and the weights ranged from 6-58 kg (median, 10). Forty-nine children (40.5%) weighed <= 10 kg. The grafts included the left lateral segment (n = 108), the left lobe (n = 12), and the right lobe (n = 1). The donors included 71 mothers, 45 fathers, 2 uncles, 1 grandmother, 1 grandfather, and 1 sister with a median age of 29 years (range, 16-53 ys) and a median weight of 68 kg (range, 47-106). Sixteen patients (12.9%) required retransplantation, most commonly due to hepatic artery thrombosis (HAT; n = 13; 10.7%). The other complications were biliary stenosis (n = 25; 20.6%), portal vein thrombosis (PVT; n = 11; 9.1%), portal vein stenosis (n = 5; 4.1%), hepatic vein stenosis (n = 6; 4.9%), and lymphoproliferative disorders (n = 8; 6.6%). The ultimate survival rate of recipients was 90.3% after 1 year and 75.8% after 3 years. Causes of early death within 1 month were HAT (n = 6), PVT (n = 2), severe graft dysfunction (n = 1), sepsis (n = 1), and intraoperative death in children with acute liver failure (n = 2). Causes of late deaths included lymphoproliferative disease (n = 3), chronic rejection (n = 2), biliary complications (n = 3), and recurrent disease (n = 3; hepatoblastoma and primary sclerosing cholangitis). Conclusions. Despite the heightened possibility of complications (mainly vascular), LRDLT represented a good alternative to transplantation from cadaveric donors in pediatric populations. It was associated with a high survival ratio.
- Rex Shunt for Acute Portal Vein Thrombosis After Pediatric Liver Transplantation in Children With Biliary Atresia(2011) GIBELLI, N. E. M.; TANNURI, A. C. A.; TANNURI, U.; SANTOS, M. M.; PINHO-APEZZATO, M. L.; MAKSOUD-FILHO, J. G.; VELHOTE, M. C. P.; AYOUB, A. A. R.; SILVA, M. M.; ANDRADE, W. C.Background/Purpose. Posttransplantation portal vein thrombosis (PVT) can have severe health consequences, and portal hypertension and other consequences of the long-term privation of portal inflow to the graft may be hazardous, especially in young children. The Rex shunt has been used successfully to treat PVT patients since 1998. In 2007, we started to perform this surgery in patients with idiopathic PVT and late posttransplantation PVT. Herein we have reported our experience with this technique in acute posttransplantation PVT. Methods. Three patients of ages 12, 15, and 18 months underwent cadaveric (n = 1) or living donor (n = 2) orthotopic liver transplantation (OLT). All patients had biliary atresia with portal vein hypoplasia; they developed acute PVT on the first postoperative day. They underwent a mesenteric-portal surgical shunt (Rex shunt) using a left internal jugular vein autograft (n = 2) or cadaveric iliac vein graft (n = 1) on the first postoperative day. Results. The 8-month follow-up has confirmed shunt patency by postoperative Doppler ultrasound. There have been no biliary complications to date. Conclusions. The mesenteric-portal shunt (Rex shunt) using an autograft of the left internal jugular or a cadaveric vein graft should be considered for children with acute PVT after OLT. These children usually have small portal veins; reanastomosis is often unsuccessful. In addition, this technique has the advantage to avoid manipulation of the hepatic hilum and biliary anastomosis. Although this study was based on a limited experience, we concluded that this technique is feasible, with great benefits to and low risks for these patients.
- Microsurgical arterial anastomosis in young and adult rats: an evolutive and comparative study(2022) SANTOS, Maria Merces; TANNURI, Ana Cristina Aoun; LACERDA, Adriana Vasconcelos; GONCALVES, Josiane de Oliveira; RICARDI, Luiz Roberto Schlaich; TANNURI, UenisPurpose: To evaluate the caliber of an arterial micro-anastomosis in the young growing animal using a continuous suture technique. Additionally, late morphological changes and blood flows distal to the anastomosis were evaluated. Methods: Seventy-four Wistar rats were submitted to laparotomy to access the aorta for blood flow measurement. The aorta was sectioned using microsurgery technique and an end-to-end anastomosis with continuous suture. After a period of six months to one year, the anastomosis was checked. Results: Regarding the size of the aortas, comparing the pre- and postoperative values, there was an increase of 13.33% in adult animals and 25% in young animals, without any difference in the blood flows. Conclusion: The arteries of young rats show signs of growth at the site of the anastomosis performed with continuous suture.
- A new simplified technique of arterial reconstruction in pediatric living-donor liver transplantation: A comparison with the classical technique(2014) TANNURI, Ana Cristina Aoun; MONTEIRO, Roberta Figueiredo; SANTOS, Maria Merces; MIYATANI, Helena Thie; TANNURI, UenisBackground/Aim: Hepatic artery anastomosis (HAA) is the most important aspect of living donor liver transplantation (LDLT), and it is currently performed by a specialized microsurgeon using micro surgical techniques, with interrupted sutures and the aid of an operative microscope. To simplify the procedure, we studied a new, simpler technique performed by pediatric transplant surgeons with continuous sutures and the same 3.5x magnification loupe used during other transplant procedures. The aim of this study was to compare these two hepatic artery reconstruction techniques in two pediatric LDLT series. Methods: This study was initiated in January 2010 and finished in June 2013. In the first period, the arterial reconstruction was performed with an operating microscope and the classical technique of 9-0 separate sutures. In the second period, the arterial reconstruction was performed using a simpler technique, with surgical loupe and continuous 8-0 Prolene sutures. The incidences and outcomes of complications within the two periods were analyzed and compared. Results: A total of 82 LDLTs were performed, 38 in the first period and 44 in the second period. There were no differences between the periods, except for the arterial ischemia time, which was lower in the second period. Conclusion: Hepatic artery anastomosis can be safely performed with low complication rates by a pediatric transplant surgeon using continuous sutures with a 3.5x magnifying loupe. This technique is simpler, less time consuming and simplifies the complex pediatric LDLT procedure.
- Which is the best technique for hepatic venous reconstruction in pediatric living-donor liver transplantation? Experience from a single center(2011) TANNURI, Uenis; SANTOS, Maria M.; TANNURI, Ana Cristina A.; GIBELLI, Nelson E.; MOREIRA, Airton; CARNEVALE, Francisco C.; AYOUB, Ali A.; MAKSOUD-FILHO, Joao G.; ANDRADE, Wagner C.; VELHOTE, Manoel C. P.; SILVA, Marcos M.; PINHO-APEZZATO, Maria L.; MIYATANI, Helena T.; GUIMARAES, Raimundo R. N.Background/purpose: The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation. Methods: Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3). Results: In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3. Conclusions: Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used.
- Orthotopic Liver Transplantation in Biliary Atresia: A Single-Center Experience(2011) TANNURI, A. C. A.; GIBELLI, N. E. M.; RICARDI, L. R. S.; SILVA, M. M.; SANTOS, M. M.; PINHO-APEZZATO, M. L.; MAKSOUD-FILHO, J. G.; VELHOTE, M. C. P.; AYOUB, A. A. R.; ANDRADE, W. C.; BACKES, A. N.; MIYATANI, H. T.; TANNURI, U.Introduction. Biliary atresia (BA) is the leading indication for orthotopic liver transplantation (OLT) among children. However, there are technical difficulties, including the limited dimensions of anatomical structures, hypoplasia and/or thrombosis of the portal vein and previous portoenterostomy procedures. Objective. The objective of this study was to present our experience of 239 children with BA who underwent OLT between September 1989 and June 2010 compared with OLT performed for other causes. Methods. We performed a retrospective analysis of patient charts and analysis of complications and survival. Results. BA was the most common indication for OLT (207/409; 50.6%). The median age of subjects was 26 months (range, 7-192). Their median weight was 11 kg (range, 5-63) with 110 children (53.1%) weighing <= 10 kg. We performed 126 transplantations from cadaveric donors (60.8%) and 81 from living-related donors (LRD) (39.2%). Retransplantation was required for 31 recipients (14.9%), primarily due to hepatic artery thrombosis (HAT; 64.5%). Other complications included the following: portal vein thrombosis (PVT; 13.0%), biliary stenosis and/or fistula (22.2%), bowel perforation (7.0%), and posttransplantation lymphoproliferative disorder (PTLD; 5.3%). Among the cases of OLT for other causes, the median age of recipients was 81 months (range, 11-17 years), which was higher than that for children with BA. Retransplantation was required in 3.5% of these patients (P < .05), mostly due to HAT. The incidences of PVT, bowel perforation, and PTLD were significantly lower (P < .05). There was no significant difference between biliary complications in the 2 groups. The overall survival rates at 1 versus 5 years were 79.7% versus 68.1% for BA, and 81.2% versus 75.7% for other causes, respectively. Conclusions. Children who undergo OLT for BA are younger than those engrafted for other causes, displaying a higher risk of complications and retransplantations.
- Hepatic Artery Graft in Pediatric Liver Transplantation: Single-Center Experience With 58 Cases(2011) BACKES, A. N.; GIBELLI, N. E. M.; TANNURI, A. C. A.; SANTOS, M. M.; PINHO-APEZZATO, M. L.; ANDRADE, W. C.; MAKSOUD-FILHO, J. G.; QUEIROZ, A. J. R.; TANNURI, U.Introduction. The use of arterial grafts (AG) in pediatric orthotopic liver transplantation (OLT) is an alternative in cases of poor hepatic arterial inflow, small or anomalous recipient hepatic arteries, and retransplantations (re-OLT) due to hepatic artery thrombosis (HAT). AG have been crucial to the success of the procedure among younger children. Herein we have reported our experience with AG. Methods. We retrospectively reviewed data from June 1989 to June 2010 among OLT in which we used AG, analyzing indications, short-term complications, and long-term outcomes. Results. Among 437 pediatric OLT, 58 children required an AG. A common iliac artery interposition graft was used in 57 cases and a donor carotid artery in 1 case. In 38 children the graft was used primarily, including 94% (36/38) in which it was due to poor hepatic arterial inflow. Ductopenia syndromes (n = 14), biliary atresia (BA; n = 11), and fulminant hepatitis (n = 8) were the main preoperative diagnoses among these children. Their mean weight was 18.4 kg and mean age was 68 months. At the mean follow-up of 27 months, multiple-organ failure and primary graft nonfunction (PNF) were the short-term causes of death in 9 children (26.5%). Among the remaining 29 patients, 2 (6,8%) developed early graft thrombosis requiring re-OLT; 5 (17%) developed biliary complications, and 1 (3.4%) had asymptomatic arterial stenosis. In 20 children, a graft was used during retransplantation. The main indication was HAT (75%). BA (n = 15), ductopenia syndromes (n = 2), and primary sclerosing cholangitis (n = 2) were the main diagnoses. Their mean weight was 16.7 kg and age was 65 months. At a mean follow-up of 53 months, 7 children died due to multiple-organ failure or PNF. Among the remaining 13 patients, 3 developed biliary complications and 1 had arterial stenosis. No thrombosis was observed. Conclusion. The data suggested that use of an AG is useful alternative in pediatric OLT. The technique is safe with a low risk of thrombosis.
- Congenital chylous ascites: A report of a case treated with hemostatic cellulose and fibrin glue(2013) MOREIRA, Daniel de Albuquerque Rangel; SANTOS, Maria Merces; TANNURI, Ana Cristina Aoun; TANNURI, UenisWe report a case of an infant with recurrent chylous ascites who was unresponsive to conventional medical treatment. An exploratory laparotomy revealed no macroscopically visible sites of lymph leakage that could be ligated. Lymph exudation was noted in areas near the subhepatic recess and in the lesser sac surrounding the pancreas, which was not amenable to suture. The treatment consisted of the placement of a hemostatic mesh composed of oxidized cellulose (Surgicel (R)) on these areas, with a thin layer of fibrinogen/thrombin glue over the mesh (Tissucol (R)). The cellulose mesh allowed for greater adhesion of the fibrin glue to the diseased tissues. The patient had no recurrence of ascites and is currently 20 months old, with good weight-height gain, and free of ascites.