Robot-assisted laparoscopic choledochojejunostomy

Background: Endoscopic stenting is the treatment of choice for palliative relief of biliary obstruction by a periampullary tumor. If treated surgically, a choledochojejunostomy and Roux-en-Y diversion is still performed by laparotomy in a large number of cases due to technical challenges of the biliodigestive anastomosis in the laparoscopic approach. Robotic systems may enhance dexterity and vision and might therefore support surgeons in delicate laparoscopic interventions. The purpose of this study is to assess the efficacy and safety of performing a laparoscopic choledochojejunostomy and Roux-en-Y reconstruction with the aid of a robotic system. Methods: Ten laparoscopic procedures were performed in pigs with the da Vinci robotic system and compared to 10 procedures performed by laparotomy (controls). Operation room time, anastomoses time, blood loss, and complications were recorded. The effectiveness of the anastomoses was evaluated by postoperative observation for 14 days and by measuring passage, circumference, and number of stitches. Results: Operating room time was significantly longer for the robot-assisted group than for controls (140 vs 82 min, p < 0.05). The anastomoses times were longer in the robot-assisted cases but not statistically significant (biliodigestive anastomosis, 29 vs 20 min; intestinal anastomosis, 30 vs 15 min), Blood loss was less than 10 cc in all robot-assisted cases and 30 cc (10–50 cc) in the controls. In both groups, there were no intraoperative complications. In the control group, one pig died of gastroparesis on postoperative day 6. In the robot-assisted group, one pig died on postoperative day 7 due to a volvulus of the jejunum. At autopsy, a bilioma was found in one pig in the robot-assisted group. In all pigs, the biliodigestive and intestinal anastomoses were macroscopically patent with an adequate passage. Circumference and number of stitches were similar. Conclusion: The safety and efficacy of robot-assisted laparoscopic choledochojejunostomy was proven in this study. The procedure can be performed within an acceptable time frame.     

Evaluation of a new vascular suture system for aortic laparoscopic surgery: an experimental study on pigs and cadavers.

OBJECTIVES: The aim of this study was to assess the feasibility and efficacy of a new laparoscopic vascular suturing device. METHODS: Animal study: six pigs underwent surgery using a retroperitoneal laparoscopic approach. Aorto-prosthetic side-to-end and end-to-end anastomoses were performed laparoscopically on each pig using SuDyn. Clamping and anastomosis times, as well as the properties of the anastomoses, were recorded. Study on cadavers: four aorto-prosthetic end-to-end anastomoses were performed using the direct transperitoneal laparoscopic approach to assess the feasibility of the SuDyn device on atherosclerotic aortas. RESULTS: Animal study: No pigs died and 12 patent and impermeable anastomoses were obtained. Mean anastomosis time was 38(+/-8)min for end-to-side anastomoses and 37(+/-5)min for end-to-end anastomoses. Study on cadavers: Totally laparoscopic anastomoses were performed in 4 human cadavers with a mean anastomosis time of 37(+/-3)min. CONCLUSIONS: SuDyn makes laparoscopic aorto-prosthetic anastomoses easier to perform, produces good results and does not require a learning curve.     

Robot-assisted aortoiliac reconstruction: A review of 30 cases

OBJECTIVE: The feasibility of laparoscopic aortic surgery with robotic assistance has been sufficiently demonstrated. Reported is the clinical experience of robot-assisted aortoiliac reconstruction for occlusive disease and aneurysm performed using the da Vinci system. METHODS: Between November 2005 and June 2006, 30 robot-assisted laparoscopic aortoiliac procedures were performed. Twenty-seven patients were prospectively evaluated for occlusive disease, two patients for abdominal aortic aneurysm, and one for common iliac artery aneurysm. Dissections of the aorta and iliac arteries were performed laparoscopically using a transperitoneal direct approach technique, a modification of the Stádler method. The robotic system was used to construct anastomoses, to perform thromboendarterectomies and, in most of the cases, for posterior peritoneal suturing. RESULTS: Robot-assisted procedures were successfully performed in all patients. The robot was used to perform both the abdominal aortic and common iliac artery aneurysm anastomoses, the aortoiliac reconstruction with patch, and to complete the central, end-to-side anastomosis in another operation. Median operating time was 236 minutes (range, 180 to 360 minutes), with a median clamp time of 54 minutes (range, 40 to 120 minutes). Operative time is defined as the time elapsed from the initial incision to final skin closure. Median anastomosis time was 27 minutes (range, 20 to 60 minutes), and median blood loss was 320 mL (range, 100 to 1500 mL). No conversion was necessary, 30-day survival was 100%, median intensive care unit stay was 1.8 days, and median hospital stay was 5.3 days. A regular oral diet was resumed after a mean time of 2.5 days. CONCLUSION: Robot-assisted laparoscopic surgery is a feasible technique for aortoiliac surgery. The da Vinci robotic system facilitated the creation of the aortic anastomosis and shortened aortic clamp time in comparison with our laparoscopic techniques.     

How safe are laparoscopic intracorporeal anastomoses?

BACKGROUND: A recent German Multicenter Study comprising 3 070 laparoscopic colorectal resections indicates that complete intracorporeal anastomoses are performed in only 1.8 % cases. The aim of our study was to review and analyse the safety of complete intracorpeal anastomosis. METHODS: In a literature survey we searched for complete intracorporeal anastomosis with different key words. RESULTS: In agreement with the literature, technically demanding hand-sutured anastomoses are no common practice. Intracorporeal anastomosis is usually done using endoscopic linear stapling devices or a conventional circular stapler by performing end-to-end, end-to-side, and side-to-side anastomoses. These techniques are more frequently used in the upper than in the lower gastrointestinal tract. CONCLUSIONS: The data published so far, however, indicates that completely intracorporeal performed anastomoses are safe in the hands of laparoscopically experienced surgeons. This technique implies very low percentages of postoperative stenoses (0-10 %) and, furthermore, very low percentages of postoperative anastomotic leakages (0-8 %).     

Laparoscopic renal autotransplantation

BACKGROUND AND PURPOSE: Renal autotransplantation is an extensive open surgical operation consisting of two distinct procedures, live-donor nephrectomy and autotransplantation, and requiring two large skin incisions. Herein, we analyze the feasibility of performing the entire procedure laparoscopically. MATERIALS AND METHODS: Renal autotransplantation was performed entirely laparoscopically in six female farm pigs. Following a left donor nephrectomy, intracorporeal renal hypothermia was achieved by intra-arterial perfusion of ice-cold solution through a 4F balloon catheter. During autotransplantation, the renal vessels were anastomosed intracorporeally to the previously prepared ipsilateral common iliac vessels in an end-to-side fashion. Laparoscopic freehand suturing (5-0 Prolene) and knot-tying techniques were employed exclusively. A staged contralateral native nephrectomy was performed in five animals. Postoperative follow-up included serial creatinine measurements, intravenous urography, aortography, and renal histologic examination. RESULTS: The mean operating time was 6.2 hours (range 5.3-7.9 hours), the venous anastomosis time was 33 minutes (range 22-46 minutes), the arterial anastomosis time was 31 minutes (range 27-35 minutes), and the total iliac clamping time was 77 minutes (range 62-88 minutes). The total renal ischemia time was 68.7 minutes: warm ischemia 5.1 minutes, cold ischemia 33 minutes and rewarming 31 minutes. Serum creatinine concentrations remained stable: baseline 1.3 mg/dL, after autotransplantation 1.1 mg/dL, and after contralateral nephrectomy 1.6 mg/dL. Intravenous urography and aortography prior to euthanasia (N = 5) demonstrated prompt contrast uptake and excretion by the autotransplanted kidneys and patent arterial anastomoses, respectively. Histopathologic examination of the autograft demonstrated normal renal architecture. CONCLUSIONS: Renal autotransplantation can be performed utilizing laparoscopic techniques exclusively. This study may form the basis for performance of complex urologic vascular procedures laparoscopically.     

PVA gel as a potential adhesion barrier: a safety study in a large animal model of intestinal surgery

Background

Intra-abdominal adhesions following surgery are a major source of morbidity and mortality including abdominal pain and small bowel obstruction. This study evaluated the safety of PVA gel (polyvinyl alcohol and carboxymethylated cellulose gel) on intestinal anastomoses and its potential effectiveness in preventing adhesions in a clinically relevant large animal model.

Methods

Experiments were performed in a pig model with median laparotomy and intestinal anastomosis following small bowel resection. The primary endpoint was the safety of PVA on small intestinal anastomoses. We also measured the incidence of postoperative adhesions in PVA vs. control groups: group A (eight pigs): stapled anastomosis with PVA gel compared to group B (eight pigs), which had no PVA gel; group C (eight pigs): hand-sewn anastomosis with PVA gel compared to group B (eight pigs), which had no anti-adhesive barrier. Animals were sacrificed 14 days after surgery and analyzed.

Results

All anastomoses had a patent lumen without any stenosis. No anastomoses leaked at an intraluminal pressure of 40 cmH₂O. Thus, anastomoses healed very well in both groups, regardless of whether PVA was administered. PVA-treated animals, however, had significantly fewer adhesions in the area of stapled anastomoses. The hand-sewn PVA group also had weaker adhesions and trended towards fewer adhesions to adjacent organs.

Conclusion

These results suggest that PVA gel does not jeopardize the integrity of intestinal anastomoses. However, larger trials are needed to investigate the potential of PVA gel to prevent adhesions in gastrointestinal surgery.     

Transfer of training in robotic-assisted microvascular surgery

BACKGROUND: Transfer of training refers to the ability to transfer acquired skills from one discipline to another. This study aims to determine whether experience in traditional freehand microsurgery facilitates mastery of robotic microsurgery. METHODS: Microsurgical anastomoses of coronary arteries harvested from explanted pig models were used to demonstrate whether prior experience with microsurgery is required in learning robot-assisted microsuturing. Eighty microsurgical anastomoses were performed. Three fully trained vascular surgeons (n = 3) (Group A) and 5 midlevel surgical residents (n = 5) (Group B) performed the anastomoses. Each subject performed 5 freehand and 5 robotic-assisted (Zeus robotic system) anastomoses. Anastomosis time and integrity of anastomoses were recorded, including errors of management (EOM) (breaking suture, breaking knots, breaking or damaging needles). RESULTS: For fully trained surgeons, all anastomoses in the robotic-assisted group were mechanically intact. There was significantly increased anastomosis time with the robot (Robot: 14 minutes, versus freehand: 7.2 minutes, P < 0.01). The robotic-assisted anastomoses were associated with a higher EOM (Robot: 1.2, versus freehand: 0.3, P < 0.01).Surgical trainees had longer anastomosis times with robotic assistance (Robot: 14.8 minutes, versus freehand, 12.7 minutes; P < 0.01) and increased EOM (Robot: 1.6, versus freehand: 1.0; P < 0.05).Overall, surgical trainees and fully trained vascular surgeons had longer anastomotic times with robotic assistance [Robot: 14.0 versus 14.8 minutes; P = not significant (NS)], and EOM (Robot: 1.6, versus freehand: 1.2; P = NS) were not significantly different. CONCLUSION: The technical feasibility of performing a safe and efficient robotic-assisted microsurgical anastomosis in explanted vessels was repeatedly tested and demonstrated in this study within reasonable time required for the anastomosis. Compared with conventional microanastomosis, both fully trained surgeons and residents demonstrated an ability to master the robotically assisted procedure with similarly longer anastomosis times and EOM. This study indicates that robotically assisted microanastomosis can be mastered equally well by surgical trainees and fully trained vascular surgeons.     

Laparoscopic harvesting of small bowel graft for small bowel transplantation

Background: Small bowel transplantation represents a valid therapeutic option for patients with intestinal failure, obviating the need for long-term total parenteral nutrition. Recently, reports have shown the feasibility of performing living related intestinal transplantation using segmental small bowel grafts. The limitations of this technique include inadequate harvested small bowel lengths, as compared with the lengths obtained in cadaveric small bowel harvests, and large incisions for the donor. In this pilot study, we evaluated the feasibility of laparoscopically harvesting long segments of proximal jejunum for small bowel transplantation using a porcine model. The results can be used to evaluate the potential for applying this technique in human cases. Methods: For this study 10 yorkshire pigs were used. Under general anesthesia, each pig underwent laparoscopic segmental resection of 200 cm of proximal jejunum on a vascular pedicle. The harvested graft then was autoreimplanted using an open technique by anastomosing the vascular pedicle to the superior mesenteric vessels. Success was determined 2 hours after anastomosis by visually identifying a pink graft with viable-appearing mucosa, an artery with a strong thrill, and palpable venous flow. The animals were then sacrificed. Results: The mean operation time required to laparoscopically harvest the small bowel graft was 80 min (range, 35–120 min), and the mean length of harvested graft was 220 cm (range, 200–260 cm). The mean length of the graft's vascular pedicle was 4.5 cm (range, 4–5 cm). All 10 grafts were successfully harvested laparoscopically and then reimplanted using an open technique. All the grafts maintained good vascular flow, and showed no evidence of mucosal necrosis at necropsy. Obviously, further studies would be required to examine the long-term results of reimplanting a laparoscopically harvested small bowel graft, but proposals for such studies is beyond the scope of this report. Conclusion: Minimally invasive techniques can be used to harvest proximal small bowel grafts for living related small bowel transplantation.     

Laparoscopic aortofemoral bypass. Initial experience in an animal model.

OBJECTIVE: The study objective was to evaluate the feasibility of laparoscopic aortofemoral bypass in a porcine model. SUMMARY BACKGROUND DATA: Laparoscopic techniques have been applied to numerous general and thoracic surgical procedures. Their application to vascular surgery has been virtually nonexistent. Open surgery for aortoiliac occlusive disease is accompanied by significant morbidity rates, and minimally invasive procedures have the disadvantage of reduced patency rates. Laparoscopic aortofemoral replacement has the theoretical advantage of long-term patency with reduced postoperative complications. METHODS: Between January and September 1993, laparoscopic surgery was performed on 16 pigs: 6 underwent transperitoneal laparoscopic aortic dissection and vessel control alone; 7 underwent complete transperitoneal laparoscopic aortofemoral bypass; and 3 underwent a retroperitoneal approach. The aortic anastomosis was performed using a combination of sutures and titanium clips in an end-to-side fashion in five pigs, and a custom-made nonsutured graft was secured with use of an end-to-end method in five pigs. Femoral anastomoses were performed with the standard open technique. RESULTS: Technical success was achieved in all 10 animals and with no major complications. Mean blood loss was 20 ml (range, 5-50 ml), and mean operative time was 2.45 hours (range, 2-4 hrs). On aortic-clamp release, 2 of the end-to-side anastomoses required additional sutures to stop bleeding between oversized staples, and 2 of the end-to-end anastomoses required additional ties to reinforce loose ties. All 10 grafts and anastomoses were patent and free of leaks after completion of the procedure. CONCLUSIONS: Laparoscopic aortofemoral bypass is technically feasible in a porcine model. Further experimental work with new instrumentation and technical refinement will make laparoscopic surgery feasible for the treatment of vascular disease in humans.     

Comparison of running and interrupted vesicourethral anastomoses in a porcine model

PURPOSE: To compare running and interrupted suturing techniques for porcine vesicourethral anastomosis with regard to procedure time, histopathologic effects, and leakage. MATERIALS AND METHODS: Twelve domestic pigs were randomized to a running (N = 6) or an interrupted (N = 6) vesicourethral anastomosis with polyglycolic acid sutures. In each case, the bladder was drained for 7 days. A cystogram was performed immediately after completion of each anastomosis and on postoperative days 7 and 30. Animals were sacrificed on postoperative day 30, and the area of the anastomosis was excised en bloc for histopathologic evaluation. RESULTS: All procedures were completed laparoscopically. The mean operative time for continuous and interrupted suturing were 27.5 and 36.8 minutes, respectively (P = 0.3324). A significant learning curve was noted for both anastomoses, with operative times decreasing with experience in both groups. There was no difference in anastomotic leakage. Histopathology examination revealed more muscle-layer fibrosis in the interrupted- suture group than in the continuous-suture group, with a mean score of 2.17 and 1.67, respectively (P = 0.0325). CONCLUSIONS: Both continuous and interrupted vesicourethral anastomoses are feasible. In this in-vivo porcine comparison, there was no difference with respect to procedure time or anastomotic leakage. However, histopathologic grading demonstrated greater muscle fibrosis in the interrupted-suture group.     

Are there advantages to robotic-assisted surgery over laparoscopy from the surgeon’s perspective?

The advantages of a robotic approach are often difficult to quantify for surgical procedures that can be performed laparoscopically. Using a novel subjective rating scale, this study demonstrates a methodology to measure surgeon assessment of ease of use, comparing complex operations performed robotically and laparoscopically. A subjective assessment scale for robotic surgery was developed that included 13 task-related factors assessing operative challenges and ease of use. As part of a larger study comparing outcomes of laparoscopic and robotic biliary-enteric anastomosis, a surgeon performing 20 choledochojejunal anastomoses in an ex vivo pig model completed this scale after each procedure. Ten anastomoses were performed laparoscopically and ten using da Vinci robot assistance. Overall difficulty was also assessed using a 10-cm visual analog scale. Robotic surgery was associated with superior ease to laparoscopy in 8 of the 13 factors, including image quality, depth perception, comfort, eye fatigue, dexterity, precision of motion, speed of motion, and range of motion. The visual analog scale also showed a significant benefit in overall ease of the robotic over laparoscopic procedure. Nonsignificant trends favoring robotics were seen with fluidity of motion and equipment setup. Based on these results this study suggest that surgeon ease of use may be quantified using this assessment scale and that robot assistance may be advantageous over laparoscopy when performing complex surgical tasks in an ex vivo model from the surgeon’s perspective.     

Taking Posterior Rectus Sheath Laparoscopically to Reinforce the Gastrojejunostomy in Laparoscopic Roux-en-Y Gastric Bypass

Background: The Roux-en-Y gastric bypass (RYGBP) is now performed laparoscopically widely with low morbidity and mortality. However, in some cases long-term adequate weight loss is not satisfied because of dilatation of the gastrojejunostomy. Therefore, a prosthetic material and bio-membranes have been used to prevent dilatation. In this study, we used posterior rectus sheath by laparoscopy, to evaluate feasibility and safety of the procedure. Methods: 20 Yorkshire pigs, under general anesthesia, had a standard laparoscopic RYGBP. In addition, 10 had their gastrojejunostomy anastomosis wrapped with 2x10 cm posterior rectus sheath. Clinical and operative outcome after operation were compared with the control group of laparoscopic RYGBP cases. Results: The median weight of the pigs was 46.1 kg (range 42-51) in the posterior rectus sheath-applied group and 45.2 kg (range 42-49) in the control group. All gastrojejunostomies in the posterior rectus sheath-applied group were successfully reinforced laparoscopically. Both groups loss weight compared with their normal growth weight, but there was no significant difference in the median weight loss between the two groups. Two pigs in the posterior rectus sheath-applied group developed a stenosis at the gastrojejunostomy anastomosis following RYGBP. All pigs in the posterior rectus sheath-applied group were found to develop hypertrophic smooth muscle and connective tissue scarring at the gastrojejunostomy on histologic examination. Conclusion: Laparoscopic application of posterior rectus sheath around the gastrojejunostomy in laparoscopic RYGBP is feasible and safe. The sheath-applied group developed stenosis and connective tissue scarring. Additional research is needed to evaluate effectiveness in preventing dilation of the anastomosis.     

Laparoscopic vascular anastomoses: does robotic (Zeus–Aesop) assistance help to overcome the learning curve?

Background Considerable training is necessary to master laparoscopic suturing and knot-tying. Robotic systems are assumed to facilitate these skills and shorten the learning curve. The effect of laparoscopic experience and robotic assistance on the learning curve of vascular anastomoses was studied. Methods A laparoscopically experienced surgeon and a laparoscopically inexperienced surgeon made alternating laparoscopic vascular anastomoses and robot-assisted laparoscopic vascular anastomoses using a Zeus–Aesop surgical robotic system with various prosthetic conduits and suture materials in a laparoscopic training box. Results Neither laparoscopic method influenced the quality score or leakage rate, but with laparoscopic experience, significantly fewer failures were made. Suturing and knot-tying were faster with laparoscopic experience both with and without the robotic system, and fewer stitch actions and knot actions were performed. The learning curves of both surgeons were not improved by the robotic system. Conclusions Experience is the most important factor in the performance of laparoscopic vascular anastomoses. The robotic system was not helpful in shortening the learning curve.     

Robot-assisted laparoscopic surgery of the infrarenal aorta

Background Recently introduced robot-assisted laparoscopic surgery (RALS) facilitates endoscopic surgical manipulation and thereby reduces the learning curve for (advanced) laparoscopic surgery. We present our learning curve with RALS for aortobifemoral bypass grafting as a treatment for aortoiliac occlusive disease. Methods Between February 2002 and May 2005, 17 patients were treated in our institution with robot-assisted laparoscopic aorto-bifemoral bypasses. Dissection was performed laparoscopically and the robot was used to make the aortic anastomosis. Operative time, clamping time, and anastomosis time, as well as blood loss and hospital stay, were used as parameters to evaluate the results and to compare the first eight (group 1) and the last nine patients (group2). Results Total median operative, clamping, and anastomosis times were 365 min (range: 225–589 min), 86 min (range: 25–205 min), and 41 min (range: 22–110 min), respectively. Total median blood loss was 1,000 ml (range: 100–5,800 ml). Median hospital stay was 4 days (range: 3–57 days). In this series 16/18 anastomoses were completed with the use of the robotic system. Three patients were converted (two in group 1, one in group 2), and one patient died postoperatively (group 1). Median clamping and anastomosis times were significantly different between groups 1 and 2 (111 min [range: 85–205 min] versus 57.5 min [range: 25–130 min], p < 0.01 and 74 min [range: 40–110 min] versus 36 min [range: 22–69 min], p < 0.01, respectively) Total operative time, blood loss, and hospital stay showed no significant difference between groups 1 and 2. Conclusions Robot-assisted aortic anastomosis was shown to have a steep learning curve with considerable reduction of clamping and anastomosis times. However, due to a longer learning curve for laparoscopic dissection of the abdominal aorta, operation times were not significantly shortened. Even with robotic assistance, laparoscopic aortoiliac surgery remains a complex procedure. Presented at SAGES 2006, April 26–29 2006, Dallas, Texas, USA An erratum to this article can be found at     

Robot-assisted Laparoscopic Aortobifemoral Bypass for Aortoiliac Occlusive Disease: Early Clinical Experience

BACKGROUND: Robotic technology may facilitate laparoscopic aortic reconstruction. We present our early clinical experience with laparoscopic aortobifemoral bypass, aided by two different robotic surgical systems. METHODS: Between February 2002 and April 2004, we performed eight robot-assisted laparoscopic aorto-bifemoral bypasses for aortoiliac occlusive disease. All patients were male; median age was 55 years (range: 36-64). Dissection was performed laparoscopically and the robotic system was used to construct the aortic anastomosis. RESULTS: A robot-assisted anastomosis was successfully performed in seven patients. Median operative time was 405 min (range: 260-589), with a median clamp-time of 111 min (range: 85-205). Median blood loss was 900 ml (range: 200-5800). Median anastomosis time was 74 min (range 40-110). In two patients conversion was necessary, one due to bleeding of an earlier clipped lumbar artery after completion of the anastomosis, the other because of difficulties with the laparoscopic exposure of the aorta. On post-operative day 3 one patient died unexpectedly as a result of a massive myocardial infarction. Median hospital stay was 7.5 days (range: 3-57). CONCLUSION: Our initial experience with robotic assisted laparoscopic surgery (RALS) shows it is a feasible technique for aortoiliac bypass surgery. However, laparoscopic aortoiliac surgery demands considerable experience and operative times need to be reduced before this technique can be widely implemented.     

Hand-assisted laparoscopic autoaugmentation gastrocystoplasty

Background: Autoaugmentation gastrocystoplasty has been previously performed successfully. This set of experiments was conducted to determine the feasibility of performing autoaugmentation gastrocystoplasty laparoscopically. Methods: Hand-assisted laparoscopic autoaugmentation gastrocystoplasty was performed on 15 mongrel dogs. The surgery was carried out with two 10-mm trocars and a 6-cm Pfannenstiel incision. The gastric wedge, supplied by the right gastroepiploic artery, was resected with two applications of an endoscopic gastrointestinal anastomosis (GIA) stapler. The pedicle was demucosalized, and the anastomosis to the bladder was completed through the Pfannenstiel incision. Results: All of the dogs were successfully treated laparoscopically and were eating at 48 h. There was no evidence of anastomotic leak dehiscence at the gastric resection staple line. Conclusion: Hand-assisted laparoscopic autoaugmentation gastrocystoplasty can be performed successfully in dogs. This operation may offer a superior alternative to standard bladder autoaugmentation procedures in children suffering from congenital bladder disorders.     

Different techniques of laparoscopic end-to-end small-bowel anastomoses

The aim of the study was to prove that laparoscopic stapling devices can be used to create a bowel anastomosis. Three groups with n=6 pigs each were subjected to different techniques of small-bowel anastomoses. In groups I and II anastomosing of the bowel ends was carried out with singly placed staples using a hernia stapler. (Group I: Two-thirds of the circumference became inverted and one-third everted. Group II circumferentially everted). In group III triangular everted anastomoses were produced using a linear noncutting stapler. All animals survived the observation period of 14 days and were postmortally examined. Average construction time was 59 min for groups I and III and 47 min for group II. Average diameters were 14 mm, 16 mm, and 18 mm for groups I, II, and III, respectively. There were no significant differences between the techniques concerning the stability of the anastomoses as expressed by bursting pressures. There were two stenoses in group I animals caused by electrocautery during preparation of the bowel ends prior to anastomosing. Anastomotic insufficiencies or fistulas were not observed clinically or with Gastrografin studies. We conclude that anastomoses in the pig can laparoscopically be constructed by employing singly placed staples as well as a linear stapler. Further investigations of these techniques on large bowel and human specimens are required prior to their clinical use in humans.     

Laparoscopic biliopancreatic diversion with a duodenal switch for morbid obesity: a feasibility study in pigs

BACKGROUND and PURPOSE: Biliopancreatic diversion with a duodenal switch is an emerging open procedure that appears as effective as other bariatric operations. Our goal was to determine the safety and feasibility of performing this procedure using a laparoscopic approach in a porcine model. MATERIALS and METHODS: Six 50-kg pigs underwent surgery. Intake was restricted with a sleeve gastrectomy, and malabsorption was obtained by creating a Roux-en-Y. The Roux limb served as a 150-cm alimentary channel following anastomosis to a transected proximal duodenum, while the other limb, or biliopancreatic channel, transported digestive juices. Where the two limbs joined, a 100-cm common channel was formed. RESULTS: The operation was completed in a mean time of 4.5 hours. Two of the six pigs had an intraoperative duodenoenterostomy anastomotic leak detected on methylene blue testing. This leakage was thought to be related to pig anatomy and is not expected to be a problem in humans. At necropsy, all anastomoses were patent, and there were no enteroenterostomy leaks or mesenteric torsions. CONCLUSION: On the basis of the porcine model, laparoscopic biliopancreatic diversion with a duodenal switch is anticipated to be feasible and safe in humans. Substantial weight loss combined with the benefits of laparoscopic surgery can be expected.     

达芬奇机器人系统辅助右半结肠切除术

目的 探讨达芬奇机器人系统辅助右半结肠切除术的安全性与可行性.方法 总结2010年5-11月完成的5例达芬奇辅助右半结肠切除术的方法 及术后恢复情况.结果 5例患者行右半结肠切除,其中1例同时行胆囊切除.手术均顺利完成,无中转开腹.手术时间140～200 min,术中失血量30～80 ml.术后无并发症发生.结论 达芬奇机器人系统应用于右半结肠癌手术是安全可行的.

Abstract：

Objective To investigate the safety and feasibility of robot-assisted laparoscopic right hemicolectomy for colonic cancer. Methods These 5 patients with ascending colonic cancer received robot-assisted laparoscopic right hemicolectomy. Results All operations were performed successfully. There was no postoperative complications. Da Vinci surgical system was found to be associated with fewer hemorrhage, rapid postoperative intestinal recovery, and therefore a shorter hospital stay. Conclusions Robot-assisted laparoscopic right hemicolectomy can be applied safely and with feasibility for colonic cancer.     

Robot-assisted versus standard videoscopic aortic replacement. A comparative study in pigs.

BACKGROUND: Reconstruction of the infrarenal aorta for aneurysms is routinely performed through laparotomy. A less invasive videoscopic approach has not gained wide acceptance due to technical difficulties. Robotic systems could potentially improve imaging of the operative field and surgeon's dexterity during videoscopic surgery and therefore might facilitate the performance of this procedure. The aim of this animal study was to compare the safety and efficacy of a robot-assisted videoscopic aortic replacement to the standard videoscopic approach. MATERIALS AND METHODS: In 10 female pigs, the infrarenal aorta was partially replaced by a 10 mm polytetrafluoroethylene (PTFE) interposition graft through a videoscopic retroperitoneal approach, using the da Vinci robot system (robot group). Ten other pigs were operated on in a similar fashion, using standard videoscopic instruments (control group). Relevant procedure times, blood loss and complications were registered. Efficacy of the anastomoses was evaluated by measuring patency and blood loss after removing the clamps. Furthermore, circumference and number of stitches were evaluated at autopsy. RESULTS: The procedure, suturing and clamping times were significantly shorter in the robot group and blood loss was less. In the control group, the inferior vena cava was injured in one pig. In two cases in the control group, haemostasis could not be established after clamp removal. At autopsy, all anastomoses in the robot group were adequate. In the control group, a stitch crossing the aortic lumen was found in two distal anastomoses and a large distance (>3 mm) between two stitches was encountered at least once in 12/20 suture lines. All 20 grafts were patent. No anastomotic narrowing was encountered. The number of stitches used for proximal and distal anastomosis was higher in the robot group. CONCLUSION: This study demonstrates the superiority of robot-assisted videoscopic aortic replacement over standard videoscopic techniques in an animal model.