Allogeneic anorectal transplantation in rats: technical considerations and preliminary results.

Fecal incontinence is a challenging condition with numerous available treatment modalities. Success rates vary across these modalities, and permanent colostomy is often indicated when they fail. For these cases, a novel potential therapeutic strategy is anorectal transplantation (ATx). We performed four isogeneic (Lewis-to-Lewis) and seven allogeneic (Wistar-to-Lewis) ATx procedures. The anorectum was retrieved with a vascular pedicle containing the aorta in continuity with the inferior mesenteric artery and portal vein in continuity with the inferior mesenteric vein. In the recipient, the native anorectal segment was removed and the graft was transplanted by end-to-side aorta-aorta and porto-cava anastomoses and end-to-end colorectal anastomosis. Recipients were sacrificed at the experimental endpoint on postoperative day 30. Surviving animals resumed normal body weight gain and clinical performance within 5 days of surgery. Isografts and 42.9% of allografts achieved normal clinical evolution up to the experimental endpoint. In 57.1% of allografts, signs of immunological rejection (abdominal distention, diarrhea, and anal mucosa inflammation) were observed three weeks after transplantation. Histology revealed moderate to severe rejection in allografts and no signs of rejection in isografts. We describe a feasible model of ATx in rats, which may allow further physiological and immunologic studies.

Single-session baseline virtual reality simulator scores predict technical performance for laparoscopic colectomy: a study in the swine model.

OBJECTIVE: Virtual reality (VR) simulation helps reducing the learning curve of laparoscopic colectomy. Moreover, it may be used to ascertain surgeons' pretraining skills. It was aimed to establish predictive validity of specific parameters gathered during VR simulation training on sigmoid colectomy and whether simulator parameters correlate with technical performance during the same operation in a swine model. DESIGN: Surgeons novice to laparoscopic colectomy underwent a single VR simulation session on sigmoid colectomy. Next, all participants performed a laparoscopic sigmoidectomy in the swine. Operations were recorded. Performance evaluation was conducted by 2 board-certified colorectal surgeons blinded to surgeons' simulator scores using an instrument specific to laparoscopic colectomy. For each participant, a mean score of specific skills was calculated. Linear regression analysis was used to identify simulator parameters that were best related to the score. The stepwise method was used to select parameters. The magnitude of the regression model was measured by the coefficient of determination (R(2)) value. SETTING: The University of Sao Paulo Medical Center is a high-volume, public practice, university-affiliated hospital. PARTICIPANTS: A total of 14 first-year residents in digestive tract surgery were included. RESULTS: Analysis of variance demonstrated that the regression model was significant (p = 0.0001), and an association between simulation scores and specific skills was confirmed. The R(2) value was 99%. The VR simulator parameters that strongly correlated with specific skills during laparoscopic colectomy in the swine were safe use of electrosurgery/energy device and safety of medial-to-lateral dissection. CONCLUSIONS: A single VR simulation session for novice surgeons in the sigmoid colectomy module generates baseline scores that highly correlated with performance of specific skills during a laparoscopic colectomy in the swine. This information may be useful in an attempt to tailor VR simulator practice according to a surgeon's needs.

Short-duration virtual reality simulation training positively impacts performance during laparoscopic colectomy in animal model: results of a single-blinded randomized trial : VR warm-up for laparoscopic colectomy.

BACKGROUND: Several studies have demonstrated skills transfer after virtual reality (VR) simulation training in laparoscopic surgery. However, the impact of VR simulation training on transfer of skills related to laparoscopic colectomy remains not investigated. The present study aimed at determining the impact of VR simulation warm-up on performance during laparoscopic colectomy in the porcine model. METHODS: Fourteen residents naive to laparoscopic colectomy as surgeons were randomly assigned in block to two groups. Seven trainees completed a 2-h VR simulator training in the laparoscopic sigmoid colectomy module (study group). The remaining seven surgeons (control group) underwent no intervention. On the same day, all participants performed a sigmoid colectomy with anastomosis on a pig. All operations were video recorded. Two board-certified expert colorectal surgeons independently assessed performance during the colectomy on the swine. Examiners were blinded to group assignment. The two examiners used a previously validated clinical instrument specific to laparoscopic colectomy. The primary outcome was the generic and specific skills score values. RESULTS: Surgeons undergoing short-duration training on the VR simulator performed significantly better during laparoscopic colectomy on the pig regarding general and specific technical skills evaluation. The average score of generic skills was 17.2 (16.5-18) for the control group and 20.1 (16.5-22) for the study group (p = 0.002). The specific skills average score for the control group was 20.2 (19-21.5) and 24.2 (21-27.5) for the study group (p = 0.001). There was acceptable concordance (Kendall's W) regarding the video assessment of generic (W = 0.78) and specific skills (W = 0.84) between the two examiners. CONCLUSIONS: A single short-duration VR simulator practice positively impacted surgeons' generic and specific skills performance required to accomplish laparoscopic colectomy in the swine model.

Loop ileostomy morbidity: timing of closure matters.

PURPOSE: Diverting stomas are commonly performed during ileoanal and coloanal anastomoses. We studied a series of patients after loop ileostomy closure to determine risk factors and the impact of the interval from primary operation on morbidity. METHODS: Ninety-three consecutive patients undergoing loop ileostomy closure at a single institution after coloanal or ileoanal anastomosis were retrospectively reviewed. Complications were classified as medical or surgical according to its treatment requirements. Results were correlated to clinical and operative features. RESULTS: Of the 93 patients, 43 were male and 50 were female with mean age of 56 years. Overall, complication rate was 17.2 percent. The most common complication was small-bowel obstruction. Complications required operative management in 3.2 percent and medical management alone in 14 percent. There was no mortality. There was no correlation between complication occurrence and age, gender, type of suture (manual or mechanical), and operative time. Complications were significantly associated with primary disease and shorter interval between primary operation and ileostomy closure. Regarding the optimal interval between primary surgery and ileostomy closure, the cutoff value for increased risk of developing postoperative complications was 8.5 weeks, below which the risk of such occurrence was significantly higher with a sensitivity rate of 88 percent. CONCLUSIONS: Diverting loop ileostomy adds little cumulative morbidity to the primary operation and is a safe option for diversion to protect a low colorectal anastomosis. To further reduce morbidity, the interval between primary operation and ileostomy closure should be no shorter than 8.5 weeks.

Surgical treatment of rectal prolapse: experience and late results with 51 patients.

UNLABELLED: The "best" surgical technique for the management of complete rectal prolapse remains unknown. Due to its low incidence, it is very difficult to achieve a representative number of cases, and there are no large prospective randomized trials to attest to the superiority of one operation over another. PURPOSE: Analyze the results of surgical treatment of complete rectal prolapse during 1980 and 2002. METHOD: Retrospective study. RESULTS: Fifty-one patients underwent surgical treatment during this period. The mean age was 56.7 years, with 39 females. Besides the prolapse itself, 33 patients complained of mucous discharge, 31 of fecal incontinence, 14 of constipation, 17 of rectal bleeding, and 3 of urinary incontinence. Abdominal operations were performed in 36 (71%) cases. Presacral rectopexy was the most common abdominal procedure (29 cases) followed by presacral rectopexy associated with sigmoidectomy (5 cases). The most common perineal procedure was perineal rectosigmoidectomy associated with levatorplasty (12 cases). Intraoperative bleeding from the presacral space developed in 2 cases, and a rectovaginal fistula occurred in another patient after a perineal rectosigmoidectomy. There were 2 recurrences after a mean follow-up of 49 months, which were treated by reoperation. CONCLUSION: Abdominal and perineal procedures can be used to manage complete rectal prolapse with safety and good long-term results. Age, associated medical conditions, and symptoms of fecal incontinence or constipation are the main features that one should bear in mind in order to choose the best surgical approach.

Surgical treatment of rectal prolapse: experience and late results with 51 patients

A técnica cirúrgica mais apropriada para a correção da procidência retal permanece motivo de controvérsia. Por se tratar de afecção pouco freqüente, há dificuldade de avaliação de número adequado de pacientes em estudos randomizados e existe pouca evidência para comprovar a superioridade de alguma das técnicas. OBJETIVO: Analisar os resultados de eficácia e segurança do tratamento cirúrgico da procidência retal em pacientes operados entre 1980 e 2002. MÉTODO: Estudo retrospectivo. RESULTADOS: Cinqüenta e um pacientes foram operados. A idade média foi de 56,7 anos e 39 eram mulheres. Além do prolapso, 33 pacientes queixavam-se de eliminação de muco, 31 tinham incontinência anal, 14 apresentavam constipação, 17 com sangramento retal e 3 incontinência urinária. Operações abdominais foram realizadas em 36 (71%) casos, sendo a retopexia sem prótese a operação mais realizada (29 casos) seguida pela retossigmoidectomia com retopexia (5 casos). A operação perineal mais realizada foi a retossigmoidectomia com plastia dos elevadores (12 casos). O sangramento sacral foi a única complicação intra-operatória e ocorreu em dois casos. Como complicação pós-operatória, houve um caso de fístula retovaginal após operação de retossigmoidectomia perineal. Após seguimento médio de 49 meses, observamos recidiva da procidência em 2 casos. CONCLUSÕES: Operações abdominais e perineais podem ser utilizadas com segurança e eficácia no tratamento cirúrgico da procidência do reto. A idade, a presença de afecções associadas, comorbidades e os sintomas de constipação e incontinência são as principais variáveis envolvidas na escolha da operação. As operações de retopexia abdominal e retossigmoidectomia perineal estão associadas a bons resultados.