Desensibilización y trasplante renal: plasmaféresis-IVIG a dosis estándar en pacientes con alto riesgo inmunológico / Desensitization and renal transplant: plasmapheresis/IVIG standard dose in patients with high immunological risk

Introducción: Los pacientes con alto riesgo inmunológico siguen siendo relegados a la cada vez más larga lista de espera de un donador inmunológicamente compatible. El objetivo de esta comunicación es informar la experiencia de un centro de trasplantes en la desensibilización de pacientes con alto riesgo inmunológico. Material y métodos: Estudio descriptivo y retrospectivo de todos los pacientes sometidos a trasplante renal de noviembre de 1999 a enero de 2008, en quienes se llevó a cabo desensibilización pretrasplante renal. Resultados: Ocho pacientes presentaron aloinmunización (pruebas cruzadas positivas o panel reactivo de anticuerpos alto, PRA > 30 %). La desensibilización se realizó mediante sesiones de plasmaféresis con recambio de 1.5 volúmenes plasmáticos, y posterior a cada una se administró una dosis estándar de inmunoglubulina intravenosa (IVIG 5 g/dosis). La inmunosupresión se inició en la primera sesión de plasmaféresis con base en un inhibidor de calcineurinas (tacrolimus); en seis pacientes se añadió mofetil micofenolato y en dos, sirolimus. En siete se obtuvieron pruebas cruzadas negativas con el donador previo al trasplante; en el octavo no se efectuaron. En dos se administró anticuerpos humanizados contra CD25 (20 mg/dosis de basiliximab). Todos los pacientes han mantenido función estable del injerto. Conclusiones: De acuerdo con nuestra experiencia, la sobrevida del injerto renal en pacientes con alto riesgo inmunológico posterior a un adecuado protocolo de desensibilización y estrecha vigilancia postrasplante es similar a la observada en pacientes no sensibilizados, al menos durante el primer año del trasplante.

BACKGROUND: Patients with high immunological risk have been relegated to the growing waiting list for an immunologically compatible donor. Our objective was to report the experience of a transplant center in desensitization of patients with high immunological risk. METHODS: We carried out a descriptive and retrospective study. Included were all the renal transplant patients from November 1999 to January 2008 in which we used plasmapheresis and standard dose of intravenous immunoglobulin (IVIG) as desensitization. RESULTS: Eight patients had history of alloimmunity (positive crossmatch or high panel-reactive antibodies (PRA >30%). Desensitization was accomplished with plasmapheresis and exchange of 1.5 plasma volume. Subsequent to each session we administered a standard dose of IVIG (5 g/dose). Immunosuppression began equal to the first plasmapheresis with calcineurin inhibitor (tacrolimus) plus six patients with mycophenolate mofetil and two patients with sirolimus. In seven cases, negative crossmatches were obtained before the transplantation, except in the eighth case in whom it was not done. Two patients received human antibodies against CD25 (basiliximab, 20 mg/dose). During their evolution, all patients maintained stable graft function. CONCLUSIONS: According to our experience, renal graft outcome in patients with high immunological risk after an adequate desensitization protocol is similar to that observed in nonsensitized patients, at least during the first year of transplantation.

Endoscopia en cirugía bariátrica: un nuevo reto? / Endoscopy and bariatric surgery: a new challenge?

BACKGROUND: Obesity in Mexico appears with a frequency of 38.4% in men and 43.3% in women. Within the therapeutic options, bariatric surgery is defined as the only effective treatment in the long term, and the number of procedures is increasing. Postoperative complications are sometimes challenging for those who are evaluating them. We undertook this study to describe and to correlate endoscopic findings with gastrointestinal symptoms in patients who have undergone a bariatric procedure. METHODS: This was a descriptive, prospective and longitudinal study that included all patients who underwent bariatric surgery between January 2004 and October 2006 and who presented gastrointestinal symptoms requiring postoperative endoscopic evaluation. RESULTS: Thirty-six patients were subjected to 45 videoendoscopies between January 2004 and October 2006. The most frequent endoscopic findings were normal postsurgical anatomy (18 patients, 50%), marginal ulcer (5 patients, 13.8%), stomal stenosis (8 patients, 22.2%), and migration of gastric band (1 patient, 2.7%). Abdominal pain was the most frequent symptom, appearing in 58.3% of patients, mainly in those with normal endoscopy. Nausea and vomiting were reported in 55.5% of the cases; 25% of the procedures done in the first 6 months were normal as compared with 75% of the cases that were done after 6 months. CONCLUSIONS: Normal videoendoscopy was the most frequent finding among patients who had undergone a bariatric procedure. Stomal stenosis was the most frequent abnormality. The presence of abdominal pain beginning 6 months postoperatively is a characteristic that predicts normal videoendoscopy.

Entrenamiento en un biosimulador y su impacto sobre la destreza en colecistectomía laparoscópica / Biosimulator training and its impact on skill in laparoscopic cholecystectomy

Objetivo: determinar el impacto educacional del entrenamiento en un biosimulador inanimado en términos de efectividad, tiempo y complicaciones, respecto a la colecistectomía laparoscópica. Material y métodos: estudio comparativo, experimental de una cohorte, prospectivo y longitudinal. Tres médicos residentes de primer año de cirugía y un interno de pregrado, fueron entrenados y evaluados en habilidades laparoscópicas elementales mediante el empleo de un biosimulador (maniquí de fibra de vidrio en el que se introducen órganos de animales ex vivo). Los sujetos fueron su propio control: realizaron un procedimiento inicial en el que se determinó tiempo quirúrgico, complicaciones y efectividad. Posteriormente observaron un corto video que mostraba el desarrollo idóneo de la colecistectomía, y en el que se identificaban las desviaciones específicas del desempeño adecuado. Posteriormente cada sujeto realizó 10 procedimientos. Resultados: no existieron diferencias en la evaluación inicial de habilidades elementales. Los individuos completaron todos los procedimientos propuestos. Las disecciones de las estructuras císticas y de la vesícula biliar fueron 61 % más rápidas al finalizar el estudio (p < 0.001); la tasa de complicación fue de 0.67 % (p <0.009). Conclusión: el entrenamiento de habilidades en cirugía endoscópica por medio de un biosimulador inanimado es mejor que el entrenamiento tradicional, ya que disminuye el tiempo quirúrgico y las complicaciones en la sala de operaciones.

OBJECTIVE: We undertook this study to determinate the educational impact of training in an inanimate biosimulator in terms of effectiveness, time and complications in performing laparoscopic cholecystectomy. METHODS: We used a comparative, experimental cohort, prospective and longitudinal. Three first-postgraduate-year residents and one pre-grade internship physician were trained and assessed in basic laparoscopic skills using a biosimulator (fiberglass [quot ]dummy[quot ] where animal organs are introduced ex-vivo). The participants acted as their own control, performing a procedure to determine surgical time, complications and effectiveness. Later they observed a short video demonstrating the suitable development of laparoscopic cholecystectomy. The video defined the specific deviations from the ideal cholecystectomy, which were considered as errors. Every procedure was videotaped, beginning with the careful dissection of cystic structures and clipping them, continuing with the dissection of the gallbladder from the liver with the standardized method. Each participant performed ten procedures. RESULTS: There were no differences in baseline assessment of basic skills. All participants completed all proposed procedures. Surgical time was 61% faster at the end of the study (p<0.001), as well as demonstrating a lower rate of complications of 0.67% (p<0.009). CONCLUSIONS: Skills training in endoscopic surgery by means of an inanimate biosimulator is superior to traditional training because it decreases surgical time and surgical complications without ethical considerations and the effect of a learning curve in the operating room.