HB - Gastrenterologia
Permanent URI for this community
Browse
Browsing HB - Gastrenterologia by Subject "Animais"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
- Endoscopic closure of transmural bladder wall perforationsPublication . Lima, E; Rolanda, C; Osório, L; Pêgo, JM; Silva, D; Henriques-Coelho, T; Carvalho, JL; Bergström, M; Park, PO; Mosse, CA; Swain, P; Correia-Pinto, JBACKGROUND: Traditionally, intraperitoneal bladder perforations caused by trauma or iatrogenic interventions have been treated by open or laparoscopic surgery. Additionally, transvesical access to the peritoneal cavity has been reported to be feasible and useful for natural orifice translumenal endoscopic surgery (NOTES) but would be enhanced by a reliable method of closing the vesicotomy. OBJECTIVE: To assess the feasibility and safety of an endoscopic closure method for vesical perforations using a flexible, small-diameter endoscopic suturing kit in a survival porcine model. DESIGN, SETTING, AND PARTICIPANTS: This pilot study was performed at the University of Minho, Braga, Portugal, using six anesthetized female pigs. INTERVENTIONS: Closure of a full-thickness longitudinal incision in the bladder dome (up to 10 mm in four animals and up to 20 mm in two animals) with the endoscopic suturing kit using one to three absorbable stitches. MEASUREMENTS: The acute quality of sealing was immediately tested by distending the bladder with methylene-blue dye under laparoscopic control (in two animals). Without a bladder catheter, the animals were monitored daily for 2 wk, and a necropsy examination was performed to check for the signs of peritonitis, wound dehiscence, and quality of healing. RESULTS AND LIMITATIONS: Endoscopic closure of bladder perforation was carried out easily and quickly in all animals. The laparoscopic view revealed no acute leak of methylene-blue dye after distension of the bladder. After recovery from anaesthesia, the pigs began to void normally, and no adverse event occurred. Postmortem examination revealed complete healing of vesical incision with no signs of infection or adhesions in the peritoneal cavity. No limitations have yet been studied clinically. CONCLUSIONS: This study demonstrates the feasibility and the safety of endoscopic closure of vesical perforations with an endoscopic suturing kit in a survival porcine model. This study provides support for further studies using endoscopic closure of the bladder which may lead to a new era in management of bladder rupture and adoption of the transvesical port in NOTES procedures.
- Experimental foundation for natural orifice transluminal endoscopic surgery and hybrid natural orifice transluminal endoscopic surgeryPublication . Lima, E; Rolanda, C; Autorino, R; Correia-Pinto, JNatural orifice transluminal endoscopic surgery (NOTES) is one of the most exciting concepts that has emerged recently in the surgical field. All accesses to the abdominal cavity in the porcine model using natural orifices, e.g. transgastric, transvesical, transcolonic and transvaginal, have been described and explored. The experimental feasibility of all procedures by NOTES was successfully demonstrated in the porcine model using different types of natural orifices. However, few translations to the human have been made. NOTES is in a developmental stage and much work is still needed to refine techniques, verify safety and document efficacy. This paper is an update on the experimental foundation for NOTES and hybrid NOTES and examines the opportunities presented by this new surgical vision.
- In vivo assessment of gastrotomy closure with over-the-scope clips in an experimental model for varicocelectomyPublication . Rolanda, C; Lima, E; Silva, D; Moreira, I; Pêgo, JM; Macedo, G; Correia-Pinto, JBACKGROUND: Gastrotomy closure remains the major limiting factor for human translation of transgastric surgery; the over-the-scope clip (OTSC) system was proposed as a possibility for this purpose. Transgastric access is good for a pelvic approach, making varicocelectomy a possible indication for natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE: To evaluate the reliability of the OTSC system in vivo after transgastric testicular vessel ligation (varicocelectomy model). DESIGN: There were 3 experimental groups (5 animals in each): groups 1 and 3, gastrotomy dilation up to 18 mm, surgery was performed with a double-channel endoscope; group 2, gastrotomy dilation up to 13 mm, surgery was performed with a single-channel endoscope. SETTING: Surgical Sciences Research Domain, Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. INTERVENTIONS: Bilateral testicular vessel ligation by transgastric access. Gastrotomy closed with the largest version of OTSC system (12 mm): a single clip in groups 1 and 2, and 2 clips in group 3. Animals were monitored for 2 weeks, killed, and submitted for necropsy. MAIN OUTCOME MEASUREMENTS: Adequacy of closure and healing after the use of the OTSC system. Statistical analysis. RESULTS: Vessel ligation was easily achieved in all groups. Although differences in the complication rate did not reach statistical significance (P = .099), there was a clear tendency for a better prognosis in groups 2 and 3 than group 1. In fact, only 2 animals from group 1 had complications related to incomplete gastrotomy closure. LIMITATIONS: Small number of animals per group; nonrandomized study. CONCLUSIONS: The OTSC system was shown to be easy and efficient for gastrotomy closure in a survival experimental model of varicocelectomy, when correctly matching the gastrotomy size with the clip size and/or number.
- Peroral esophageal segmentectomy and anastomosis with single transthoracic trocar: a step forward in thoracic NOTESPublication . Rolanda, C; Silva, D; Branco, C; Moreira, I; Macedo, G; Correia-Pinto, JBACKGROUND AND STUDY AIMS: A transesophageal natural orifice transluminal endoscopic surgery (NOTES) approach has been proposed for thoracic and mediastinal access. Similarly to transgastric surgery, serious limitations remain related to creating an esophagotomy and its safe closure. A hybrid approach in thoracic NOTES could work as an intermediate step before pure transesophageal NOTES. We assessed the benefit of hybrid thoracic NOTES for peroral segmental esophagectomy and subsequent complete esophageal anastomosis with a single transthoracic port. METHODS: Two protocols were used to attempt esophago-esophageal anastomosis: ex vivo using a phantom model (n = 5), and in vivo after esophageal mobilization, and segmental esophagectomy achieved using either a gastroscope (flexible) (n = 5) or thoracoscope (rigid) instruments (n = 5). A forward-viewing double-channel endoscope and a transthoracic operative thoracoscope with a working channel were coordinated in order to create a complete single-layer, end-to-end esophageal anastomosis ex vivo as well as in vivo. Feasibility and anastomosis quality were evaluated by inside and outside assessment of: patency, the incorporation of mucosa in all stitches, and a leak test. RESULTS: Anastomosis was achieved in all ex vivo experiments and thoracoscopically-led in vivo procedures. All anastomoses were patent, allowing distal passage of the endoscope, with mucosa incorporation. In in vivo experiments, a leak was detected in three animals and corrected with additional stitching. CONCLUSIONS: Peroral esophageal anastomosis with a single transthoracic trocar is feasible, which may represent a step forward in thoracic NOTES.
- Third-generation nephrectomy by natural orifice transluminal endoscopic surgeryPublication . Lima, E; Rolanda, C; Pêgo, JM; Henriques-Coelho, T; Silva, D; Osório, L; Moreira, I; Carvalho, JL; Correia-Pinto, JPURPOSE: Recently there has been increasing enthusiasm for performing simple abdominal procedures by transgastric surgery. We previously reported the usefulness of a combined transgastric and transvesical approach to cholecystectomy. In this study we assessed the feasibility of combined transgastric and transvesical approach for performing a more complex surgical procedure, such as nephrectomy, in a porcine model. MATERIALS AND METHODS: In a nonsurvival study combined transgastric and transvesical approaches were established in 6 female pigs. Under ureteroscope guidance we installed a transvesical 5 mm over tube into the peritoneal cavity and a flexible gastroscope was passed orally into the peritoneal cavity by a gastrotomy. We performed right or left nephrectomy with instruments introduced by the 2 devices that worked in the renal hilum, alternating device intervention for dissection and retraction procedures. RESULTS: Four right and 2 left nephrectomies were performed. There were no complications during the creation of transvesical and transgastric access. In all animals we visualized the 2 kidneys. The renal vessels and ureter were reasonably individualized and ligated separately with ultrasonic scissors, which were introduced through the transvesical port. In 2 early cases mild hemorrhage occurred after ultrasonic ligation. To overcome this complication we applied clips successfully before ultrasonic ligation in the remaining animals. Thus, complete renal release and mobilization to the stomach were achieved in all animals. CONCLUSIONS: Nephrectomy by natural orifices using the combined transgastric and transvesical approach is technically feasible, although to our knowledge there is no reliable method for removing the specimen with current instruments.
- Transesophageal pulmonary lobectomy with single transthoracic port assistance: study with survival assessment in a porcine modelPublication . Moreira-Pinto, J; Ferreira, A; Miranda, A; Rolanda, C; Correia-Pinto, JBACKGROUND AND STUDY AIMS: Thoracoscopic pulmonary lobectomy is being performed in an increasing number of patients. The aims of the current study were to assess natural orifice transluminal endoscopic surgery (NOTES) as an alternative to transthoracic endoscopic surgery, and to test the feasibility of peroral transesophageal right upper pulmonary lobectomy with the assistance of a single transthoracic trocar. METHODS: In 10 acute and 4 survival pigs, right upper pulmonary lobectomy was performed using a forward-viewing double-channel gastroscope and an operative thoracoscope with a 5-mm working channel inserted through a single transthoracic 12-mm) port. Time, safety, and feasibility of the following steps were recorded in all animals: esophagotomy, hilar dissection, individual ligation of the hilum elements, pulmonary lobectomy, and specimen retrieval. In the survival experiments, esophagotomy was closed using a reticulated laparoscopy suture device and an esophageal stent was placed. These animals were kept alive and monitored for 2 weeks. RESULTS: Esophagotomy was performed safely in all animals (mean procedure duration 5.4 ± 1.7 minutes). Dissection of the right upper lobe hilum elements (bronchus, arteries, and veins) was carried out without adverse events. Individual ligation of the hilum elements was performed in all but two cases (time for dissection and ligation 44.2 ± 14.8 minutes). Lobectomy and specimen retrieval were completed in all animals (9.5 ± 3.1 minutes). Esophagotomy closure and stent placement were carried out in 20.0 ± 2.8 minutes in the survival animals. These animals fed normally and gained weight postoperatively without signs of disease. Endoscopic examination before necropsy revealed a pseudo-diverticulum in one animal, and wound dehiscence with confined collection/recess in the remaining animals. CONCLUSIONS: Transesophageal right upper pulmonary lobectomy using single transthoracic trocar assistance is feasible and may represent a step towards scar-free pulmonary lobectomy.
- Transvesical endoscopic peritoneoscopy: a novel 5 mm port for intra-abdominal scarless surgery.Publication . Lima, E; Rolanda, C; Pêgo, JM; Henriques-Coelho, T; Silva, D; Carvalho, JL; Correia-Pinto, JPURPOSE: Recently various groups reported successful attempts to perform intra-abdominal surgery through a transgastric pathway. We assessed the feasibility and safety of a novel transvesical endoscopic approach to the peritoneal cavity through a 5 mm port in a porcine model. MATERIALS AND METHODS: Transvesical endoscopic peritoneoscopy was performed in 8 anesthetized female pigs, including 3 nonsurvival and 5 survival animals. Under cystoscopic guidance a vesical hole was created on the ventral bladder wall with an open-ended ureteral catheter. An over tube with a luminal diameter of 5.5 mm was placed in the peritoneal cavity, guided by a 0.035-inch guidewire. In all animals we performed peritoneoscopy of the entire abdomen as well as liver biopsy and falciform ligament section. A vesical catheter was placed for 4 days in all survival animals, which were sacrificed by day 15 postoperatively. RESULTS: After a learning curve in the first 3 nonsurvival animals the creation of a vesical hole and placement of the over tube were performed without complication in all survival animals. In these animals we easily introduced an EndoEYEtrade mark into the peritoneal cavity, which provided a view of all intra-abdominal viscera, as well as a 9.8Fr ureteroscope, which allowed simple surgical procedures without complications. In survival experiments all pigs recovered. Necropsy examination revealed complete healing of the vesical hole and no signs of infection or adhesions into the peritoneal cavity. CONCLUSIONS: Transvesical endoscopic peritoneoscopy was technically feasible and it could be safely performed in a porcine model. This study provides encouragement for additional preclinical studies of transvesical surgery with or without combinations with other natural orifices approaches to design new intra-abdominal scarless procedures in what seems to be third generation surgery.