First year experience of robotic-assisted laparoscopic surgery with 153 cases in a General Surgery Department: indications technique and resultsV. Tomulescu, O. Stãnciulea, I. Bãlescu, S. Vasile, St. Tudor, C. Vasilescu, I. Popescu, C. Gheorghe
Original article, no. 2, 2009
* Center of General Surgery and Liver Transplantation
* Center of Gastroenterology and Hepatology
The technical advances play a key role in various fiels of medicine, especially nowadays in surgery. Ten years after Philippe Mouret performed the first laparoscopic cholecystectomy this technique became the golden standard in the treatment of many diseases (cholelithiasis, ITP, GERD and hiatal hernia, etc.). There was time for a new ”revolution”. Himpens et al. reported the first successful clinical application of telerobotics in 1997 when they performed a laparoscopic cholecistectomy using a da Vinci prototype (1).
Although laparoscopic surgery brings clear benefits to the patients surgeons face distinct disadvantages: working through fixed entry points limits maneuverability of the instruments inside the body cavity, looking at a two-dimensional screen, surgeons are handicapped by the loss of the visual depth perception, the need for a human assistant to hold and move the camera makes surgeons lose the independent ability of controlling the operation field (2).
Telemanipulator robots have been developed in response to limitations placed on the surgeon by endoscopic surgery: reduced visual quality and control, reduced dexterity related to the instrumentation, ergonomics.
The Da Vinci system consists of two primary components: the surgeon’s viewing and control console (Fig. 1) and a movable cart with three articulated robot arms (Fig. 2). The surgeon is seated in front of the console and manipulates handles that are similar to “joysticks” while viewing a high-resolution, truly three-dimensional image of the surgical field through binoculars (Fig. 3). Manipulation of the handles transmits electronic signals to the computer, which can control and modify the movement of instrument tips by downscaling the movements, by eliminating physiologic tremor, and by adjusting grip strength applied to the tools. The computer generates electrical impulses that are transmitted by a 10 meter long cable and command the three articulated robot arms. Disposable laparoscopic articulated instruments are attached to the distal part of two of these arms and introduced inside the abdomen through trocars mounted on the arms. The third arm carries an endoscope with dual optical channels, one for each of the surgeon’s eyes. Some of the major advantages of robotic system are: stabile camera platform, three dimensional imaging, significant decrease limitation in the movement of instruments [Endowrist instruments (Fig. 4), have 7 degrees of freedom - the arms have 3 degrees of freedom-pitch, yaw and insertion allow the appropriate instrument to move 2 additional degrees of freedom in the wrist and 2 additional motion for tool actuation], tremor filtration and comfortable position for surgeon (3,4).
In the first years of robotic surgery a number of various procedures were reported: in 1999 the first Nissen fundo-plication was performed for gastro-esophageal reflux by Cadierre et al. (5); in the same year the group also reported the first obesity surgery (6); in 2001 were reported: first robotic adrenalectomy by Hogan and co. (7); first robotic Heller myotomy in treatment of achalasia by Melvin et al. (8), thoracoscopic thymectomy usig a da Vinci in a 74- year-old male patient with thymoma was communicated by Yoshino J. in 2001 (9).
In the years to come robotic surgery was applied in treatment of a number of esophageal, gastric, colonic and rectal cancers (10-12).
In 2008 a “da Vinci S” robotic system was acquired in the Center of General surgery and Liver Transplantation of Fundeni Clinical Institute. The aim of this paper is to present our preliminary experience with the three-arms da Vinci S surgical system, to assess the feasibility of this technique in various abdominal and thoracic procedures and to point out the advantages of the robotic approach for each procedure.
Matherials and Methods
Between January 2008 and January 2009 in the Center of General surgery and Liver Transplantation of Fundeni Clinical Institute 3909 surgical procedures were performed (including 45 liver transplantation and minim invasive procedures). From the 547 cases operated miniminvasivelly 153 patients underwent robotic-assisted surgical procedures, with approval from our hospital ethical committee and after obtaining informed consent of each patient. The operations were performed by 3 teams, including 3 senior surgeons, 4 young surgeons and 4 scrub nurses.
There were 66 men and 87 women. Mean age was 48,02 years , range 6 to 84 years. We performed 129 abdominal and 24 thoracic procedures, detailed in Table 1.
All but six procedures reported were completed in terms of robotic approach (96,07%), 5 of them converted to open surgery. One case of right adrenal metastasis, in spite the preoperatively ct scan, was found intraoperatively to invade the vena cava and an open lateral resection of the vena cava was necessary. One case of gastric tumor were found to have invaded the adiacent organs, the procedure was converted to open surgery and a subtotal palliative gastrectomy was performed; in one case of stage II B cervix tumor conversion to open surgery was necessary due to adherent lymphnodes and anatomical difficulty; in the case of obstructive jaundice caused by local invasive pancreatic cancer with porthal invasion a robotic cholecisthectomy was performed and coledocoduodenal anastomosis was converted to an open the procedure due to pericholedocian vascular bleeding; in one case of portal cavernoma the procedure was converted to open surgery after performing robotic splenectomy due to diffuse bleeding. One system malfunction was registered in one case of large hiatal hernia repair and the procedure was converted to laparoscopy.
Average operating room time was 171 minutes (range 60 to 600 minutes). Median length of stay was 8,6 days(range 2 to 48 days). There were no deaths.
Postoperatory medical/surgical complications occurred in a total of 14 (9.15%) patients. A pancreatic leak after a left adrenalectomy was treated conservatively. After a robotic low anterior rectal resection (LAR) a prolonged sanguine drainage appeared, probably in relation with mechanical anastomosis, and was conservatively treated. A thoracic duct lesion occurred after a left extensive thymectomy for stage I Masaoka thymoma and was solved conservatively. The mixed cervical and robotic thoracic approach for cervicomediastinal goitre was accompanied with a transitory recurrent nerves paralysis in a patient with a very large tumor; the use of corticoterapy and voice abstinence helped obtaining the good outcome. Radical hysterectomy was associated with one case of deep venous thrombosis and an urinary incontinence, both cases were resolved with medical treatment. An inferior left lobe pneumonia appeared in a case of a very large transhiatal hernia and a difficult intrathoracic dissection following surgery. Anthibiotherapy and quick mobilization of the patient solved this complication. There were four cases that required reoperations (2,6%). One of our first cases of hiatal hernia and GERD has complicated with bleeding from a trocar site that imposed laparoscopic reoperation in the first postoperative day. One patient with low anterior rectum resection and liver cirrhosis, with an anastomotic leak well tolerated who presented the 12th postoperative day a severe intra abdominal bleeding from the IMA stump, that required reoperation for hemostasis control and conversion of the anastomosis to a terminal colostomy. Another patient with a low anterior resection of the rectum for rectal cancer underwent a reoperation with viscerolisis for ileal obstruction in the 7’th postoperative day. One patient with Idiopathic thrombocytopenic purpura (ITP) underwent emergency open surgery in the same day after robotic splenectomy for diffuse abdominal bleeding.
Planning the surgical procedure - patient selection
Based on our extensive experience in advanced laparoscopy (arround 500 cases/year) we decided from the beginning to approach robotically a difficult and heterogeneous pathology. We refered to robotic surgery cases that were previously performed in laparoscopic approach (splenectomies, benign pathology of eso-gastric junction, thymectomies, colo-rectal procedures, hepatic resection) as well as cases never approached in laparoscopic practice (gastrectomies). All the cases with cholelithiasis have been referred to laparoscopic approach. We continue to use laparoscopic surgery in cases of colorectal procedures that requires an approach to more than one quadrant, that are more time consuming and difficult to be performed by robotic approach. Laparoscopic approach is the first option also for patients with hydatid cysts referred to minimal invasive procedures due special maneuvers necessary to be performed to avoid intraoperative contamination.
The patients referred to robotic surgery needs to be carefully and completely investigated preoperatively. The investigation must be done preferably in the same centre. We had four cases of conversions to open surgery due entirely too insufficient preoperatively examination. In the case of invasive adrenal tumor A CT scan with fine slides and IV contrast would have shown us the invasion, the same for the patient with cervical cancer. The eco-endoscopy is mandatory in robotic gastric surgery. We have converted one case of a bleeding gastric cancer due to pancreatic invasion and unresectable lymphnodes around the celiac trunk evaluated by robotic approach (only capsular invasion observed openly) that imposed us an open palliative subtotal gastrectomy.
It is a known fact that in case the robotic procedure fails the first option is to convert to the laparoscopic procedure; only the intraoperative findings (the tumor were found to have invaded the adjacent organs) conducted us to convert to the open surgery. We do not consider that in these cases a laparoscopic approach could have solved those cases minimivasivelly.
There was one intraoperative device failures that resulted in a case conversion to laparoscopic procedures (0,65%). A paper published by Zorn et al. - a group of urologists from Chicago, reported in an experience of 700 consecutive robotic - assisted radical prostatectomies device failure rate -0%, procedure abortion 0,5% and surgeon handicap in 0,4% of procedures (13). The conversion occurred in a difficult case of large hiatal hernia with entire stomach ascended in the thoracic cavity showing the incontestable benefit of robotic surgery by ergonomic point of view and in relation with difficult dissection.
A proctor was present to perform and then to supervise the first three procedures: cholecisthectomy, Heller myotomy and hepatic bisegmentectomy. Despite learning the basics of the robot with this first cholecistectomy case we avoided this procedure and reserved the robotic approach for much complex procedures. Initially the procedures were performed by three experienced laparoscopic surgeons; after soon noticed that our more complex cases moved along much smoother, another three young surgeons (young specialists and even senior residents) were able to perform under strict supervision the following procedures: a subtotal gastrectomy, a Heller myotomy, two splenectomies, a Nissen fundoplication, 2 right colon resections, a low anterior rectal resection and a left lateral liver resection. There were no intra or postoperative complications in these cases. A number of 4 new residents were also trained for the side assistant position, allowing us to quickly enlarge the team. Both residents and staff became more comfortable much quicker with robotic surgery than with the laparoscopic procedures, revealing a shorter learning curve for previously trained laparoscopic surgeons.
After performing the first 153 robotic assisted procedures we will present some specific key points for each group of interventions, showing the advantages of robotic surgery in abdominal and thoracic procedures.
Robotic surgery for gastric tumors
The gastric tumor patient referred to robotic surgery needs to be carefully investigated preoperatively. There are some specific investigations there must to be done in each patient in order to precisely locate the tumor and its spread to the adjacent organs: upper endoscopy with multiple biopsies, endoscopic ultrasound, CT scan and chest X-ray. Because of the lack of the tactile sense it is very important to determine preoperatively what type of gastrectomy will be performed (total gastrectomy-subtotal gastrectomy). The following indications are suitable for the robotic assisted gastric surgery: early gastric cancer, small tumors, GIST, gastric lymphoma, palliative surgery. In cases where an extended lymphadenectomy is needed robotic surgery is also indicated because an accurate dissection is much easier to achieve. For that reason some authors performed laparoscopic gastric resection and robotic assisted lymphadenectomy in the same procedure (14,15). Voluminous tumors and tumors spread to adjacent organs are considered contraindications of the robotic assisted surgery. The most important benefit of robotic surgery in gastric tumors is a safe and accurate lymphodissection.
Treatment of benignant pathology of eso-gastric junction
Laparoscopic procedures for GERD, hiatal hernia repair and achalasia are now “the golden standard” in surgical treatment of this benignant pathology of eso-gastric junction. Given the limited space for dissection and the need to mobilize the great gastric curvature, robotic Nissen fundoplication and other anti-reflux techniques seems adequate for robotic surgery. First robotic assisted Nissen procedure was reported by Cadierre in 1999 (5). Randomized controlled trials have demonstrated that laparoscopic Nissen fundoplication give similar results to the robotic approach, but it is less expensive and less time consuming (16,17)
We consider as Talamini that robotic system is very usefull in dissecting and repairing large hiatal hernias (18). The dissection of a hernial bag fixed in the thorax in this large hernias is easier with small versatile robotic instruments and suturing with robotic instruments is more appropriate compairing to open surgery (19).
Potential complications after laparoscopic esocardio-myotomy are: failure secondary to undivided circular muscle fibers, perforation of the esophageal mucosa and progression of disease. The extra magnification and excellent three-dimensional imaging can help prevent esophageal perforation and identify residual circular muscle fibers. This robotic system allows easier and safer dissection of eso-gastric junction and enables surgeons to better perform operations due to the high quality of visualization and enhanced precision (Fig. 5). Reinterventions, even in cases of failure after previous open approaches can be safe performed with robotic “da Vinci” platform.
Total and partial splenectomy
Robotic assisted total splenectomy was described in previous studies as a safe and valuable alternative to the laparoscopic procedure (20,21).
The major drawback is the fact that the most important haemostatic instruments (Ligasure, Stapplers) are used from the side-assistent trocar. In our opinion the robotic system is useful in performing a splenectomy for splenomegaly. The enhanced vision and Endowrist instruments allowed us to perform a safe dissection of the spleen vessels with minimal blood loss. In our splenomegaly cases we secured the spleen vessels with intracorporeal knots, procedure that is more time-consuming (Fig. 6). We consider that splenectomy for ITP, especially in children is easy to be performed by laparos-copic approach using Ligasure, and with better cosmesis (using only three trocars).
In cases of partial splenectomy, especially in heamatologic diseases such as hereditary shperocytosis,the enhanced vision allows us to better evaluate the splenic remnant volume. As we previously reported, the spleen remnant volume must be around 10-15% of the enlarged spleen (22). The preservation of the lower pole of the spleen was preferred in these cases.
The first reported robotic adrenalectomy was performed by Horgan et al. in 2001 (7).
Previous studies showed that standard laparoscopic adrenalectomy is superior to robot-assisted adrenalectomy in terms of feasibility, duration, and costs. Like in the other type of procedures the robotic approach seems to be beneficial in difficult cases, like large tumors, obese patients (23,24).
From our small experience in robotic approach of liver surgery may conclude that this approach is suitable for standard laparoscopic indications - limited resections of lesions situated in accessible anterior location. There are same major drawback as in robotic surgery of the spleen; the surgeon loses control some points of the surgical procedure, as the side assistant is manipulating the Ligasure and argon beam colagulator for haemostatic control (Glissonian pedicles are approached in intraparenchimatous manner: major hepatic pedicles are usually stapled and minor pedicles are best controlled with LigaSure-Atlas™). With experience, the use of suturing, robotic ultrasonic shears or clips can replace these power devices (Fig. 7) but they are more time consuming (25). We consider that probably the robotic surgery will permit the minimally invasive approach for difficult liver lesions in relation with fine robotic dissection, better view and perfect suturing.
Several authors have reported good results with colorectal robotic surgery (12,26-29), our experience in terms of operative time, conversion rate, mortality, complications rate and length of stay are similar. The complications that appeared after robotic colo-rectal surgery (previously described) are not related to the robotic approach. We consider that in rectal cancer, total mesorectal excision with nerve sparing and lymphadenectomy is better performed by robotic approach especially in obese patients or in large tumour cases. The inferior mesenteric artery was controlled with intracorporeal knots by robotic approach and the splenic flexure mobilization performed either laparoscopically or robotically. There are different opinions of others robotic surgeons which prefer a hybrid procedure, laparoscopic splenic flexure mobilization and inferior mesenteric control, and robotic approach only for proctectomy with total mesorectal excision (10,30). Right hemicolectomy with primary ligation of the vessels for right colonic cancer can be easily performed by robotic approach. We prefer to perform extracorporeal anastomosis. The benefit of right hemicolectomy is untill now only for the learning curve in robotic colorectal surgery.
Suturing the rectum after excision of large benign lessions is easy performed even in deep male pelvis in superior conditions not only to laparoscopic surgery but even to open surgery, with good results.
In 2001, Yoshino described the first robotic thymectomy in the treatment of small thymoma. In 2003, Ashton and Rea published a case report on robotic thymectomy in MG using two different approaches: the first adopted a right-sided approach with completion of the operation through a left-sided approach, the second used a leftsided approach only (31,32).
New opportunities for robots in general surgery are those interventions in which only the robot renders possible or noticeably simplifies a minimally invasive approach, i.e. procedures in which precise dissection of delicate, vulnerable anatomic structures take place in tiny areas with difficult access (33). Thymectomy is such a procedure and robotic surgery is the choice for extended minim invasive thymectomy. Based on a large experience (over 300 cases) with thoracoscopic thymectomy for nonthymomatous and thymomatous myasthenia gravis (34) we consider that the versatile instruments and better vision of robotic surgery permit us to make an extensive thymectomy easier and safer than in usual thoracoscopic approach despite the lack of tactile sense. The tinny 7 degrees instruments are very good for cervical dissection (Fig. 8).
Radical hysterectomy with pelvic lymphadenectomy
Robotic technology has been described for gynecolocic procedures such as laparoscopic hysterectomy, sacral colpopexy, myomectomy and radical hysterectomy.
Althought followed by all the advantages of miniminvasive surgery, laparoscopic radical hysterectomy showed some difficulties regarding pelvic lymph node dissection and vaginal cuff closure (performing sutures in general). Previous studies reported a lower complication rate in robotic approach of gynecologic onclology compaired with laparoscopic and open surgery (35).
The indications for robotic approach are: gynecologic malignancies stage IA-IIA total radical hysterectomy with lymphadenectomy for endometrial cancer (35,36), and for cervical cancer (37,38).
A safe an accurate pelvic lymphadenectomy is in our opinion the main advantage of the procedure;also we could point out easyer intracorporeal sutures and a better exposure of pelvic anatomy.
Esophagectomy using a conventional minimally invasive approach is an advanced surgical procedure with a long learning curve. We have performed this technique for the first time in 2000 by thoracoscopic approach in 2 cases with good results (39). These cases have to be very well investigated and the patients in early stage of the disease. These are rare cases; most of the patients with esophageal cancer come to the surgeons in advance stages. In the case operated robotically the thoracic part has been done robotically and the abdominal part laparoscopically. We feel that dissection with the da Vinci is safer and easier. Thus far, only single case reports were published regarding robotic esophageal procedures (11,40,41). This small series of various esophageal lesions treated by robotic-assisted thoracoscopic surgery (RATS) supports the hypothesis that the esophagus is a major organ of interest for robotic surgeons.
During the procedure is difficult to place additional ports and to change the position of the operating table. Any surgeon with experience in laparoscopy knows how important the maneuverability of the operating table is, especially in rectal and gynecological surgery.
In our experience we found that the learning curve in robotic assisted laparoscopic procedures is shorter than in laparoscopic surgery, some authors suggested a number close to ten procedures (4).The explanation could be the fact that the surgeons and especially the side assistants in robotic surgery are mandatory to have experience in advance laparoscopic procedures because the laparoscopic approach is the first indicated in cases of failure of the robotic approach.
After performing 153 cases of robotic assisted laparoscopic procedures we can conclude that the robotic system will require further development of instruments for haemostatic control, some of the pedicles are approach by the side-assistant trocar using Ligasure, vascular staplers. Instruments adapted to pediatric surgery are also needed (42). Force and sensibility feedback is expected to improve the performances and consecutively the results obtained with of this system (11). In spite the need of these improvements we can conclude that the system is still underused regarding its possibilities.
Further prospective, randomized studies are required in order to prove that in spite of the high acquisition and maintenance cost the robotic system will provide far more improved results comparing to open and laparoscopic surgery.
The limitations of robotic surgery, as they were previously mentioned, will be resolved in time and the future of robotics in general surgery will be limited only by imagination. The system developments and improvement will result in the ability to program the surgical procedures and the surgeons only to supervise the intervention done by robots (43). In time we are also expect the costs, now the most limitative factor in the use of surgical robots on a large scale, to decrease.
Our preliminary experience suggests that robotic surgery is safe, feasible and worth of clinical applications. The use of robotic system allows surgeons to perform complex procedures, otherwise performed only by open procedure. We referred to robotic surgery with excellent results difficult cases for laparoscopic practice like gastrectomies, total radical hysterectomies, pelvectomies, transtoracic esofagectomy, thymomas or cervicomediastinal goitre. Reintervention after laparoscopic or open approach is in our opinion an indication for robotic surgery of benignant pathology of eso-gastric junction. The robotic system serves also in training young residents. Due to the variable distance between the console surgeon and the patient we consider the importance of side assistant surgeon(s) vital for an uneventful surgical procedure. They should be well trained surgeons in general surgery, advanced laparoscopic procedures and robotics. The best indications for robotic surgery are the procedures that require a small ,deep and fixed operating field, a fine a precise dissection (suitable for anterior mediastinum surgery, pelvic and gastric lymphadenectomy, nerve sparing in total mesorectal excision) and safe intracoroporeal sutures.
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