Laparoscopic Liver Resection: A South American Experience with 2887 Cases.

BACKGROUND: Laparoscopic liver resections (LLR) have been increasingly performed in recent years. Most of the available evidence, however, comes from specialized centers in Asia, Europe and USA. Data from South America are limited and based on single-center experiences. To date, no multicenter studies evaluated the results of LLR in South America. The aim of this study was to evaluate the experience and results with LLR in South American centers. METHODS: From February to November 2019, a survey about LLR was conducted in 61 hepatobiliary centers in South America, composed by 20 questions concerning demographic characteristics, surgical data, and perioperative results. RESULTS: Fifty-one (83.6%) centers from seven different countries answered the survey. A total of 2887 LLR were performed, as follows: Argentina (928), Brazil (1326), Chile (322), Colombia (210), Paraguay (9), Peru (75), and Uruguay (8). The first program began in 1997; however, the majority (60.7%) started after 2010. The percentage of LLR over open resections was 28.4% (4.4-84%). Of the total, 76.5% were minor hepatectomies and 23.5% major, including 266 right hepatectomies and 343 left hepatectomies. The conversion rate was 9.7%, overall morbidity 13%, and mortality 0.7%. CONCLUSIONS: This is the largest study assessing the dissemination and results of LLR in South America. It showed an increasing number of centers performing LLR with the promising perioperative results, aligned with other worldwide excellence centers.

Liver transplantation using Chagas-infected donors in uninfected recipients: a single-center experience without prophylactic therapy.

Organ shortage is the first cause of death on liver transplant waiting lists. As a consequence, we recently decided to expand liver acceptance to those organs that could potentially transmit infectious diseases to their recipients. On January 2010, we initiated a prospective protocol using livers from Chagas-infected donors for transplanting uninfected recipients without using prophylactic therapy. During a 13-month period, 9 of 37 (24%) liver transplants were performed within this protocol. After transplant, each recipient was sequentially and strictly monitored for infection transmission using the Strout method and promptly treated with benznidazole if this occurs. During follow-up, two patients died without Chagas infection and only two (donor-derived T. cruzi transmission rate: 2/9; 22%) patients developed donor-derived Chagas transmission without clinical symptoms. The median follow-up time of the seven live patients was 15 months (range: 13-20). At present, all are symptoms-free with excellent allograft function and without evidence of Chagas disease. In conclusion, we consider that Chagas-infected donors are a promising source of liver grafts that could reduce the growing mortality on liver waiting lists in America. Relevant data from larger prospective studies are required to confirm these preliminary excellent results.

Access to Grafts in a Liver Transplant Center: Does It Rely on the Severity of the Waiting List Population?

BACKGROUND: The number of transplants performed relies, partially, on recipients' variables on the waiting list. The goal of this study was to compare recipients from a high-volume liver center in Argentina with the rest of the country. METHODS: This study was a retrospective analysis of liver transplant recipients nationally between January 2013 and April 2017. It involved extracting data from the open database CRESI-SINTRA (the Argentinian database of the National Procurement Organization, an equivalent to the United Network for Organ Sharing); expressing results by percentages, medians, and interquartile ranges (IQRs); and comparing the national population with the population transplanted at Hospital El Cruce (HEC). The Mann-Whitney U test was used for analysis. RESULTS: Nationally, 1434 liver transplants were performed. A total of 177 (12.34%) were emergency status; 811 (56.6%) were by the Model for End-Stage Liver Disease (MELD) (n = 759)/PELD (Pediatric End-Stage Liver Disease) (n = 52), with a median graft assignment position of 5 (IQR, 3-10) in 57.2 days (IQR, 11-217). Median MELD access was 29 points (IQR, 24-33). A total of 446 (31.1%) had MELD exceptions; 249 (55.8%) of these were due to Milan hepatocellular carcinoma. At the HEC, 167 liver transplantations were performed; 26 (15.6%) were emergency status and 97 (58.1%) by MELD (none PELD). Their median graft assignment position was 4 (IQR, 4-16) in 19.1 days (IQR, 4-90); median MELD access was 28 points (IQR, 24-31). Forty-five patients (26.9%) had MELD exceptions; 31 (68.9%) were due to hepatocellular carcinoma. CONCLUSIONS: Our center has a larger proportion of recipients transplanted by emergency status and MELD, similar MELD access, and less waiting list time, reflecting our wide policy of liver graft acceptance.

Simultaneous observation of the quantization and the interference pattern of a plasmonic near-field.

Surface plasmon polaritons can confine electromagnetic fields in subwavelength spaces and are of interest for photonics, optical data storage devices and biosensing applications. In analogy to photons, they exhibit wave-particle duality, whose different aspects have recently been observed in separate tailored experiments. Here we demonstrate the ability of ultrafast transmission electron microscopy to simultaneously image both the spatial interference and the quantization of such confined plasmonic fields. Our experiments are accomplished by spatiotemporally overlapping electron and light pulses on a single nanowire suspended on a graphene film. The resulting energy exchange between single electrons and the quanta of the photoinduced near-field is imaged synchronously with its spatial interference pattern. This methodology enables the control and visualization of plasmonic fields at the nanoscale, providing a promising tool for understanding the fundamental properties of confined electromagnetic fields and the development of advanced photonic circuits.

Extremely marginal liver grafts from deceased donors have outcome similar to ideal grafts.

BACKGROUND: Although there is a worldwide need to expand the donor pool, many cadaveric marginal livers are usually discarded for transplantation. Herein, we report the outcome of a series of patients receiving marginal grafts. METHODS: We analyzed all patients who underwent liver transplantation in our unit from August 2006 to March 2011 (n = 125) with the use of a prospectively collected database. Patients with ≥3 of donor (prolonged hypotensive episodes, donor age >55 years, high vasopressor drug requirement, hypernatremia, prolonged intensive care unit stay, elevated transaminases) and graft-related (cold ischemia >12 hours, warm ischemia time >40 minutes and steatosis >30%) extended criteria were defined as extremely marginal liver grafts (EMLG). The outcomes of patients receiving EMLG were compared with the recipients of grafts without any marginal criteria (ideal grafts). RESULTS: The EMLG group (n = 36) showed higher operative transfusion requirement (66.6% vs 55.6%) as well as 30-day (11.1% vs 55%) and 1-year (22.2% vs 5.5%) mortality rates, compared with the ideal grafts group (n = 18) but without a significant difference. Other variables, such as major complications, postoperative hemodialysis, ICU and hospital stay, and 1-year survival also were not significantly different. CONCLUSIONS: The liver pool can be safely expanded using EMLG from deceased donors for liver transplantation. These usually discarded liver grafts showed similar early and long-term outcomes compared with ideal organs.

[Human immunodeficiency virus infection in Guatemala]. / Infeccion por virus de inmunodeficiencia humana en Guatemala.

PIP: A prospective study of HIV seroprevalence was conducted in Guatemala City and Quetzaltenango between January 30, 1990, and June 30, 1991, to furnish a realistic idea of the magnitude of seroprevalence in Guatemala. Subjects included 305 patients with proven tuberculosis (TB), 500 consecutive patients in an emergency room, 600 military recruits from different parts of Guatemala, 500 consecutive patients at a prenatal clinic, and 300 women receiving emergency room treatment for complications of abortion. Participation was anonymous and confidential. Subjects ranged in age from 18 to 40 years. Seropositivity rates were 1% for the 305 TB patients, 1% for the 500 emergency room patients, 0.2% for the 600 military recruits, 0% for the 500 pregnant women, and 0.7% for the 300 postabortion patients. Seroprevalence was low, but the presence of risk factors suggests that it will increase in the future. Sexual activity begins at young ages. 71% of military recruits reported becoming sexually active by age 15. 45-80% of TB and emergency room patients and military recruits reported having more than one sexual partner at the time of the interview. Only 2-3% of women reported having more than one partner. Between 4% and 30.7% of the five groups reported a history of sexually transmitted diseases, of which one-third were ulcerative. 17% of TB patients and 2-3% in the other groups had received blood transfusions. Fewer than 20% in any group reported ever using condoms.^ieng

Doce años de experiencia en trasplante hepático con donante vivo relacionado en el Hospital Italiano de Buenos Aires: evolución y resultados / Twelve years experience with living donor transplantation: follow-up and results

Antecedentes: El trasplante hepático es el tratamiento de elección para pacientes con enfermedad hepática terminal. La disponibilidad de órganos es el factor limitante para su empleo. El empleo de injertos provenientes de donantes vivos desde hace años se aplica a la población pediátrica y en los últimos años se ha generalizado su uso en receptores adultos. Objetivo: Analizar la experiencia con el empleo de esta técnica en nuestro programa de trasplante. Lugar de aplicación: Hospital Privado de la comunidad. Diseño: Estudio retrospectivo y descriptivo. Población: 458 pacientes a los que se le realizaron 492 trasplantes hepáticos ortotópicos (TOH). 79 (TOH) con donante vivo (50 niños y 29 adultos). Método: Se realizó la evaluación de los donantes con exámenes de laboratorio. Ecodoppler y tac abdominal, posteriormente arteriografía y biopsia hepática en caso de sospechar hepatopatía. Los niños fueron trasplantados con segmentos II y III (n = 45) o con monosegmento (n = 5). 28 adultos recibieron hígado derecho (LD) y uno hígado izquierdo (LI). Resultados: De 120 potenciales donantes pediátricos 60 fueron rechazados (50 por ciento). Presentaron complicaciones 6 de los 50 (12 por ciento). Se evaluaron 71 potenciales donantes para adultos, fueron rechazados 25 (35,2 por ciento). Cinco de los 29 (17,2 por ciento) donantes presentaron complicaciones. La indicación más frecuente fue la atresia de vías biliares en la población pediátrica (65,9 por ciento) y cirrosis por Virus C en los adultos (44 por ciento). Las complicaciones vasculares en la población pediátrica ocurrieron en 8 pacientes (16 por ciento) y las biliares en 14 (28 por ciento). La supervivencia actuarial de pacientes e injertos a 10 años fue de 94 por ciento y 90 por ciento respectivamente. Los adultos presentaron complicaciones vasculares en el 6,89 por ciento y biliares en el 37 por ciento. La supervivencia actuarial de pacientes e injertos fue de 89,8 por ciento y 89,3 por ciento al año y de 83,7 por...

Aplicación de la termoablación por radiofrecuencia en el tratamiento de los tumores de hígado: resultados preliminares / Radiofrequency thermoablation in the treatment for liver tumors: initial results

Antecedentes: La termoablación por radiofrecuencia ocupa un lugar importante actualmente en el tratamiento de los tumores malignos de hígado. Objetivo: Comunicar nuestra experiencia con el uso de la radiofrecuencia en el tratamiento de los tumores de hígado. Lugar de aplicación: Hospital privado de comunidad. Diseño: Serie de casos, retrospectivo. Material y método: 44 pacientes tratados con radiofrecuencia entre enero de 1999 y diciembre de 2002. Población: Fue dividida según el origen tumoral en: 1. primario, 2. metástasis colorrectal, 3. metástasis neuroendocrina y 4. metástasis no colorrectal no neuroendocrina. La radiofrecuencia fue utilizada: 1. como única modalidad, 2. asociada a cirugía y 3. combinada con otro procedimiento. Se evaluaron la vía de abordaje, la morbilidad, mortalidad, control local, recurrencia local y supervivencia. Resultados: Media de edad 64 años. Masculinos 65 por ciento. Origen del tumor: colorrectal 50 por ciento, hepatocarcinoma 32 por ciento y no colorrectal no neuroendocrino 18 por ciento. Vía de abordaje: Laparotómica 82 por ciento, percutánea 13,5 por ciento y laparoscópica en 4,5 por ciento. Estadía hospitalaria promedio: 4 días. Complicaciones: 8 pacientes (18 por ciento). No hubo mortalidad, ni necesidad de reoperación. Se observó una recidiva parietal luego del abordaje percutáneo. En 8 pacientes (18 por ciento) se indicó radiofrecuencia por segunda vez. Supervivencia actuarial global: 28 por ciento a los 4 años. Conclusiones: La radiofrecuencia es un procedimiento válido y seguro en pacientes seleccionados. Puede ser considerada un tratamiento alternativo en pacientes con imposibilidad o rechazo al tratamiento quirúrgico. En pacientes seleccionados la radiofrecuencia se puede indicar asociada a tratamiento quirúrgico resectivo