for Endoscopic Suturing

Fig. 25.1

Demonstrations of the Overstitch endoscopic suturing device including (a) the Olympus double channel therapeutic gastroscope with needle driver attached, (b) OverStitch system with handle and needle driver (needle anchor not shown), (c) working ends of the device with components labeled, (d) polypropylene and polydioxanone suture, (e) suture cinch device, (f) distal end of tissue helix device, and (g) overtube demonstrating specialized end inflation catheter both designed to retain gas insufflation. (Used with permission from Apollo Endosurgery)

Patient and Procedure Preparation

Frequently, endoscopic suturing procedures are performed under general anesthesia given the complexity of the related procedures, and the large caliber of devices passed per os along the esophagus. Beyond improving patient tolerance, endotracheal intubation secures the airway and allows for supine positioning with fear of pulmonary aspiration if desired for adjunct fluoroscopy. If supine position is utilized, the endoscopist will need to appreciate the possibility of decreased device response due to angulation and restriction of the tension cable. It is recommended to perform a diagnostic endoscopy to assess the area of interest and ensure the pre-procedure plan of action remains appropriate and feasible. If a foregut procedure is being performed, during this assessment, the overtube may be positioned by loading the device over the proximal end of the insertion tube, passage of the distal end into the stomach, and then careful advancement of the overtube along the insertion tube until such point as the bulbous proximal end abuts the bite block. Care should be taken to cease passage if resistance is experienced as this rarely may indicate invagination of the esophageal wall between the overtube and insertion tube, which may then result in esophageal perforation. This device also incorporates a catheter through which air may be inserted to inflate a proximal circumferential balloon designed to assist in maintaining insufflation. Moreover, the catheter may be affixed to the bite block with a hemostat or similar device to prevent outward migration with movement of the endoscope.

Suture Device Equipment Set- Up

While initially preparing and passing the system within the patient, the handle of the needle driver should be in the closed position to keep the sharp needle end of the suturing arm housed within the alignment tube and to minimize the profile of the device. The primary OverStitch system is first mounted on the Olympus dual channel therapeutic gastroscope using the scope attachment bracket at the level of the biopsy channels with a 90° angle and rocked firmly to lock the needle driver handle in rightward position onto the scope (Fig. 25.2a). With the needle driver in the closed position, the actuation cable is guided alongside the flexible insertion tube and the endcap assembly seated onto the distal end of the gastroscope, ensuring optimal alignment so as to avoid obscuring the endoscopic component (Fig. 25.2b). Next, with the suture arm now open, choose the desired suture and load its blunt end within the anchor exchange device provided with the system. The operator or assistant should press these devices together firmly until a “click” is perceived, be it audible and or tactile (Fig. 25.2c). The suture should then be run loosely along the anchor exchange, and the distal end of the anchor passed through the larger 3.7 mm rightward working channel until the distal end is several centimeters beyond the alignment tube so as to provide necessary slack, or play, allowing critical mobility while manipulating the device and suturing. The anchor and suture are then withdrawn so as to have the metal end of the suture just within the alignment tube. The needle driver handle should then be closed to move the suture arm just above the alignment tube (Fig. 25.2d). Next, the suture is loaded onto the curved needle body by again pushing the anchor exchange firmly toward the needle until resistance is met again, or a tactile click is appreciated. This represents proper insertion of the suture with the arm, though at this stage the suture also remains attached to the exchange anchor. Therefore, to release the suture from the exchange, the operator now presses the blue button at the proximal end of the exchange device and in tandem pulls gently on the exchange. Care should always be taken when pressing the release button of the exchange, as this will either release the suture to the needle or “fire” the distal end of the suture from the system to allow cinching. With the suture on the needle body, the first tissue bite may follow (Fig. 25.2e). This first suture may be loaded to the suture arm either ex vivo or in vivo; however, the former is preferred to ensure appropriate functionality of the overall system. Of course, a major advantage of this iteration of the suturing device is its ability to reload sutures without removal of the device and therefore allowing the operator to maintain constant visualization of the target.

../images/442926_1_En_25_Chapter/442926_1_En_25_Fig2_HTML.jpg — Fig. 25.2

(a) Attachment of the system handle to the endoscope. (b) The handle of the needle driver is placed on a 90° angle at the level of the biopsy channels of the scope. (c) The suture is loaded into the anchor exchange catheter. (d) The suture is threaded into the 3.7 mm gastroscope channel and once advanced beyond the needle tower is then pulled back to create a suture loop or “slack”. (e) The needle driver handle is closed so the curved body of the needle is facing the endoscopic channel and the anchor exchange catheter is pushed aligned to the curved body of the needle until resistance or a “click” is heard. Then the blue button of the anchor exchange (inset with arrow) catheter is pushed down and slightly pulled back about 1 cm simultaneously so the suture is transferred from the anchor exchange catheter to the curved body of the needle; the exchange catheter is released and the suture handle opened. (Used with permission from Apollo Endosurgery)

General Endoscopic Suturing Technique

The following steps depict the general endoscopic suturing technique . These steps are the same with minimal variations depending on the type of procedure to be performed.

Step 1: Carefully advance the dual channel therapeutic gastroscope with attached OverStitch device with the arm in closed position per os, with or without overtube, or per rectum into range of the targeted tissues of the foregut, midgut, or hindgut. With the endoscope in range, begin to plan the methods needed to achieve the desired outcome. This includes identifying what is to be apposed, the type of stitch pattern, and the sequence of sutures. For instance, the location of the first bite may in large part be determined by the decision of suture pattern and particulars of positioning. Importantly, given the nuance of over-under-under-over suture technique found with most patterns, the first bite usually involves the distal edge to be approximated, while the second is the proximal, as this will naturally allow this sequence. As the suture is loaded on the needle arm, the driver handle may then be opened to ready for the first bite. Meanwhile, the exchange catheter remains within the 3.7 mm working channel ready to recapture the suture as below (Fig. 25.3).
Step 2: While it is possible to position the needle guard and body appropriately to obtain a full thickness bite, it is recommended to utilize the tissue helix assist device to allow full control of the manipulated tissue. To do so, the device is passed through the secondary 2.8 mm leftward working channel of the therapeutic gastroscope with the distal metal spiral contained within the catheter; this may involve pulling back the blue cross on the proximal end of the device. With the helix catheter visualized endoscopically, the assistant exposes the metal spiral by pushing on the blue cross (Fig. 25.4).
Step 3: The helix is then advanced onto the tissue target, and the assistant begins to turn the blue cross clockwise 3–4 times, while the endoscopist pushes the catheter toward the tissue (Fig. 25.5). Frequently, though not always, the endoscopist will appreciate a subtle tissue bounce, and this will help ensure full thickness suturing.
Step 4: The helix catheter is then slightly withdrawn pulling the grasped tissue toward the tip of the endoscope into path of the loaded needle arum. The endoscopist may or may not slightly push forward the insertion tube or even use suction to improve alignment of the target (Fig. 25.6).
Steps 5 and 6: Next, with the tissue well within the alignment with the arm, the operator closes the needle driver handle to advance the anchor and suture though the tissues held by the helix. Without delay the anchor exchange is advanced forward to come in contact with the suture on the needle arm. As previous, a tactile click will usually, though not always, be appreciated suggesting appropriate engagement of the anchor exchanger with the suture on the needle arm (Fig. 25.7). Of importance, the suture has not yet been exchanged, and the helix remains connected with the tissue.
Step 7: Without pressing the blue button of the exchanger, gently pull the anchor exchange back to disengage the suture from the needle arm (Fig. 25.8). Again the helix remains engaged with tissues until the next step.
Step 8: The assistant next turns the helix counter clockwise a minimum of 4 rotations to release the tissue, again frequently associated with a subtle tissue bounce. The entire helix spiral should be visualized endoscopically and the catheter withdrawn slightly toward the endoscope. The assistant should then pull back on the blue cross to retract the helix, and the catheter may then be withdrawn entirely into the working channel.
Step 9: While both the sharp end of the suture is detached from the needle body and the helix from the tissue, the tissue remains engaged with the needle body until it is placed into the open position using the handle. However, in the open position, the endoscopist attempts to create some distance from the target area using the slack created while initially loading the suture with the exchanger (Fig. 25.9).
Step 10: With the first full thickness bite completed, the endoscopist next passes the suture back to the needle body to allow the process to continue. Each step above is repeated to achieve the desired suture throw.
Steps 1b–10b: The above steps are then repeated taking various bites of tissue appropriate for the chosen suture technique, be it interrupted, running, purse-string, or horizontal mattress (as described below), and the desired outcome achieved (Fig. 25.10).