Laparoscopic intracorporeal bowel anastomosis by a new suturing device: A study in a laparoscopic simulator with integrated animal organs

The colonoscopic vacuum model-simulating biomechanical restrictions to provide a realistic colonoscopy training environment

INTRODUCTION

Practicing endoscopic procedures is fundamental for the education of clinicians and the benefit of patients. Despite a diverse variety of model types, there is no system simulating anatomical restrictions and variations in a flexible and atraumatic way. Our goal was to develop and validate a new modelling approach for adhesion forces between colon and abdominal wall.

METHODS

An inlay for a standard mechanical trainer was designed and 3D printed. Colon specimens were fixed to the inlay along colon ascendens (CA) and colon descendens (CD) by a vacuum. Our system, which we refer to as Colonoscopy Vacuum Model (CoVaMo), was validated with 11 test persons with varying level of expertise. Each performed one colonoscopy and one polypectomy in the CoVaMo and in the Endoscopic Laparoscopic Interdisciplinary Training Entity (ELITE). Achieved adhesion forces, times required to fulfill different tasks endoscopically and a questionnaire, assessing proximity to reality, were recorded.

RESULTS

Mean adhesion forces of 37 ± 7 N at the CA and 30 ± 15 N at the CD were achieved. Test subjects considered CoVaMo more realistic than ELITE concerning endoscope handling and the overall anatomy. Participants needed statistically significantly more time to maneuver from anus to flexura sinistra in CoVaMo (377 s ± 244 s) than in ELITE (58 s ± 49 s).

CONCLUSION

We developed a training environment enabling anatomically and procedural realistic colonoscopy training requiring participants to handle all endoscope features in parallel. Fixation forces compare to forces needed to tear pig colon off the mesentery. Workflow and inlay can be adapted to any arbitrary ex vivo simulator.

Retroperitoneoscopic and laparoscopic suturing: tips and strategies for improving efficiency

BACKGROUND

The difficulties of minimally invasive reconstructive surgery, laparoscopically or retroperitoneoscopically, are caused by spatial limitation and fixed trocar positions and, therefore, restricted movement and handling of the instruments. In addition to a standardization of the technique, continual training, and improved instrument technologies, optimization of the geometry of reconstructive surgery, such as angles and distances between the working ports or the camera and needle position, are imperative to providing an optimal clinical performance.

MATERIALS AND METHODS

After designing a standardized suturing technique and conducting an experimental analysis of the geometric factors important in reconstructive surgery, we transferred these results to our clinical setting. A series of 116 reconstructive laparoscopic and retroperitoneoscopic procedures (nephropexy, pyeloplasty, bladder neck suspension, and radical prostatectomy) were analyzed according to the technical realization and quality of reconstruction. Trocar and table positions were adjusted according to our preliminary results, as were the position of the instruments and camera.

RESULTS

The trocar and instrument positions are critical for the clinical outcome of reconstructive surgery. Continual training in a standardized suturing technique, together with the clinical application of the important geometric rules, can reduce surgery time by 50%. The time required for suturing single knots could be decreased even more: as much as 75%, thus ensuring efficient and safe reconstructive surgery.

CONCLUSION

Reconstructive procedures such as pyeloplasty or radical prostatectomy can be standardized and performed in an acceptable amount of time with adequate quality when adhering to a standardized technique and the important geometric rules. Improved performance in terms of time and quality will increase the acceptance of these procedures, which can help to solve the problem associated with a low total number of indications for laparoscopy and retroperitoneoscopy.

Geometry of laparoscopic suturing and knotting techniques

BACKGROUND

Spatial limitation, together with a fixed trocar position, restricted handling, and movement of the instruments, is inevitably associated with reconstructive laparoscopy and retroperitoneoscopy. This problem includes not only suturing technique and instruments but also geometric factors of endoscopic reconstruction, such as optimal distances between the working trocars, length of instruments, and angles between the instruments and the object. We present an experimental access to determine the specific impact of these factors on reconstructive laparoscopy.

MATERIALS AND METHODS

In an in vitro model, end-to-end anastomoses of porcine intestine were performed using a standardized intracorporeal suturing technique. Suturing was performed without and after training in reconstructive surgery with variation of the following geometric factors: (1) the distance between the working trocars (between 6 and 12 cm); (2) the position of the object (lateral right, medially, lateral left); (3) the camera position (medially, lateral right, lateral left); (4) the angle between the instruments and a horizontal line (15 degrees , 55 degrees, 90 degrees); (5) the intracorporeal length of instruments (between 10 and 25 cm); and (6) narrowed space available for the instruments (between 4 and 25 cm).

RESULTS

Continual training decreased the time required for suturing between 30% to 50%. Training decreased the time required for nonsuturing activities between 50% and 70% but the time required for suturing activities only between 20% and 45%. If the space between instruments and camera was limited, shifting the camera into a lateral position simplified the procedure of intracorporeal suturing. Angles of <55 degrees between instruments and the horizontal line simplified laparoscopic suturing, as did angles of <45 degrees between the instruments. In cases of maximally narrowed space (diameter of 4 cm), a suture filament length of <10 cm decreased the time required by 30%.

CONCLUSION

We suggest an isosceles triangle between the instruments with an angle between 25 degrees and 45 degrees and an angle of <55 degrees between the instruments and the horizontal line as the optimal geometry for intracorporeal suturing. These data should be considered when planning a reconstructive laparoscopic procedure (i.e., alignment of trocars, table position). However, further studies are required to confirm these preliminary results.