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Basic Laparoscopic Skills Program Laparoscopic Suturing: A Primer on Technique Robert W. O’Rourke, MD Assistant Professor Department of Surgery Oregon Health and Science University 1. Needle positioning: Needle positioning is a Unfortunately, many find it tedious to practice. The ability to quickly position a needle for suturing, as well as make subtle adjustments in its angle are critical skills for the advanced laparoscopic surgeon. a. The easy way: i. Grab the suture with your left hand 5 mm from the hub of the needle- let the needle hang down in front of you. ii. Rotate your left hand instrument until the needle is positioned such that your right hand instrument can grab it so that the needle is positioned in the driver for suturing. iii. Grasp the needle with your right hand instrument in such a way that it’s positioned to suture. iv. Suture! b. The hard way: This method is important to learn, as it is much more versatile than the method above and allows for subtle changes in needle orientation. It is really simply an extension of the method above. i. Grab the suture with your left hand 5 mm from the hub of the needle- let the needle hang down in front of you. ii. Grab the needle with your right hand with a loose grip iii. Rotate your left and right hands simultaneously to position the needle for a forehand throw; now rotate again to position the needle for a backhand throw. Now rotate in each position to make subtle adjustments of the angle of your needle. iv. Repeat 100 times. v. Practice left-handed. vi. Repeat 100 times. c. Using tissue to position the needle: one-handed needle positioning. i. Grab the needle with a loose grip in your right hand. ii. Gently touch the needle tip to tissue (do not use the spleen or liver, do not push too hard and drive the needle into bowel). iii. Maintaining a loose grip on the needle, rotate your instrument so that the needle rotates in the instrument, pivoting around the needle tip, which is held in place on its contact point to the tissue. 2. Suturing: (the push-push-pull-pull technique (PPPP), better termed the rotate-rotate-rotate-rotate technique) The basic principle of the PPPP technique is to avoid tension on tissue as the needle passes through it. Rotating, rather than pushing the needle through the tissue, following the curve of the needle, accomplishes this. A twirling motion of the needle driver, rather than a pushing motion, allows for this. When tissue is tough (e.g. the stomach), you can get away with pushing. When suturing delicate tissue, however (e.g. a hemorrhaging vein), pushing will tear the tissue and worsen the situation. Be aware that this technique is very useful in open suturing as well. a. Stabilize the tissue you are suturing gently with your left hand with a closed instrument, approximately where you expect your needle to exit the tissue. b. Insert the needle in the tissue with the needle tip PERPENDICULAR to the tissue. Rotate (DO NOT PUSH) the needle through the tissue by rotating the needle driver with a twirling motion of your wrist, passing the needle through the tissue along the CURVE OF THE NEEDLE. (Push #1) c. Release the needle with your right hand, letting the tissue hold the needle (TRUST THE TISSUE). d. Gently re-grab the needle with your right hand closer to the hub of the needle, maintaining gentle stabilization of the tissue with your left hand. e. Rotate the needle through more of the tissue until the tip exits the tissue (Push #2). f. Release the needle with your right hand, letting the tissue hold the needle (TRUST THE TISSUE). Then re-grab it just below the tip that has exited the tissue. Rotate the needle through the tissue more, without pulling it all the way out of the tissue (Pull #1). g. Release the needle with your right hand, letting the tissue hold the needle (TRUST THE TISSUE). h. Re-grab the needle in its middle in such a way that you are ready to take another bite of tissue on your next suture; rotate the needle through the tissue until it exits the tissue (PULL#2). If you grabbed the needle correctly, you should be ready for another suture without having to reposition the needle. i. Take another bite! j. Repeat 100 times. k. Practice left-handed. Practice right-hand backhanded. Practice left-hand backhanded. l. Repeat each 100 times. 3. Tying: a. The first throw of a square knot: i. Place a 6-7” stitch with your right hand, such that the needle exits the tissue screen left. ii. Grab the suture with your right hand instrument: 1. 5 mm from the hub the needle 2. with the concavity of the needle driver facing away from the hub of the needle- the reason for this is to avoid having the pointy tip of the concave portion of the driver push against delicate tissues as you move the needle, and the drive against the tissue as you pass the needle through the tissue. A subtle point that makes sense only when you work with delicate tissues. 3. such that the suture exits the needle driver at right angle to the driver iii. Lengthen your long tail, shorten your short tail. One way to do this is to tug with a closed instrument on the long tail towards the LLQ of the screen, pulling the suture through the tissue. iv. Setup a C-loop: you may have already done this by tugging on the long tail. The C-loop should be in the LLQ of the screen, with the open part of the C facing the RUQ of the screen. The short tail should be in the RUQ of the screen. v. Place your left hand (accepting) instrument on top of the long tail which makes the C- loop. vi. Touch the tips of both instruments to where you expect your knot to go down-for all following movements, keep your instrument tips within 5-10 mm of where you expect your knot to go down. vii. Pass the suture over your accepting instrument, moving your right-handed (passing) instrument away from you. viii. Loop the suture around and under your accepting instrument with your right-hand passing instrument, moving the suture towards you; the suture should wrap itself around the shaft of the left-hand accepting instrument. ix. Grab the short tail with your left hand instrument. x. Pull your right hand passing instrument to the RUQ of the screen, while pulling your left hand accepting instrument to the LLQ of the screen. The suture will slide off the shaft of your left-hand instrument; as you tighten the suture, you will have just created the first throw of a square knot. xi. Now, a caveat: to really make a true first square throw, once the suture has slid off the shaft of your left hand instrument as you pull your right hand to RUQ and left hand to LLQ, rotate your hands so that you now cinch the knot down while pulling your left hand to the RUQ and your right hand to LLQ. You must cross your instruments to do this, it feels a bit awkward, but if you watch carefully, you will see that the throw goes down “square”. b. The second throw of a square knot: Both methods of creating the second throw of a knot are useful: the first method is simpler to learn. The second method avoids the extra move of dropping and then picking up the suture with the opposite hand, and may be faster, especially when you are less experienced and dropping and picking up suture takes more time, but is a bit harder to teach and learn. Learn them both. Have more than one technique up your sleeve. i. Method #1: 1. Grab the long tail 5mm from the hub of the needle with your left hand instrument (which now becomes your passing instrument, while your right hand now becomes the passing instrument. 2. Setup your C-loop in a mirror image to above, such that the C-loop is in the RLQ of the screen, with the open part of the C facing the LUQ, and the short tail is in the LUQ of the screen. 3. Repeat steps above, simply substituting your left hand instrument for your right, and your right-hand instrument for your left. Your movements are a mirror image of the first throw. ii. Method #2: 1. Maintain your grip on the long tail with your right hand instrument. 2. Place your left hand instrument under the long tail. 3. Touch the tips of both instruments to where you expect your knot to go down. For all subsequent movements, keep your instrument tips within 5-10 mm of where your knot will go down. 4. Pass the suture under your accepting instrument, moving your right hand instrument away from you. 5. Loop the suture around and over your accepting instrument with your right- hand passing instrument, moving the suture towards you; the suture should wrap itself around the shaft of the left-hand accepting instrument. 6. Grab the short tail with your left hand instrument. 7. Pull your right hand passing instrument to the LLQ of the screen, while pulling your left hand accepting instrument to the RUQ of the screen. The suture will slide off the shaft of your left-hand instrument, and as you continue pulling and tightening the suture, you will have just created the first throw of a square knot. 8. Now, the same caveat as above, but the opposite: to make a true second square throw, once the suture has slid off the shaft of your left hand instrument as you pull your right hand to LLQ and left hand to RUQ, rotate your hands so that you now cinch the knot down while pulling your left hand to the LLQ and your right hand to RUQ. You must cross your instruments to do this; it feels a bit awkward, but if you watch carefully, you will see that the knot goes down “square”. iii. Solving a common problem: the drawloop: 1. if you grasp your short tail too far away from its end, as you pull it through your knot, you will sometimes create what is called a draw-loop, when both limbs of the short tail are caught in the knot. You can prevent this by simply grasping your short tail close to the end. If you do create a draw-loop, however, there is a simply, fast way to fix it: without dropping the suture in your right hand instrument, simply move the closed tip of your right hand instrument into the draw-loop and pull-you will pop the draw-loop out of the knot, and you can then continue tying. 4. Slip Knot: When tissue is under tension, a slip-knot is necessary to bring the tissue together. Many skilled laparoscopists use a slip-knot for every knot they tie. Whatever approach you use, remember, there is more than one way to skin a cat. Have more than one technique up your sleeve. a. Make the first throw of a square knot. Do not cinch the knot down to the tissue. Do not make a granny knot. Leave the knot loose in the air. b. Make the second throw of a square knot. Cinch it down very loosely close to the first throw. c. Grab the suture attached to the needle with your right hand instrument about 1-2 cm above the loose knot. d. Grab the suture that exited the tissue last with the left hand instrument below the knot. This limb of suture sits between the tissue and the knot. If you didn’t cinch the first throw down to the tissue, there should be about 1-2 cm of suture between the tissue and the knot. e. Pull your right hand instrument to the RUQ of the screen, and your left hand instrument to the LLQ of the screen, making sure that the two strands of suture you have in each instrument are in a direct line. You will feel a “pop” as your square knot pops into two parallel hitches. f. Release the suture in your left hand instrument while maintaining your grip on the suture in your right hand instrument. With a loose grip with your left hand instrument, grab the suture you are holding with your right hand just below your right hand instrument, above the knot. g. Gently slide your left hand instrument along the suture down to the knot-when you meet the knot, your grip should be loose enough so that it will slide the knot down the suture but not so loosely that your instrument slips past the knot- rather, as you continue pushing, you should slide the knot down to the tissue, slipping it along the suture in your right hand. Conversely, don’t grasp the suture with your sliding left hand instrument so tightly that you fray the suture. This is the hard part of slipping a knot, namely learning this delicate just-tight-enough grasp on the suture. h. Rock the knot to take up and excess slack, fully tightening the knot. Repeat your slip with each rock until the knot is snug against the tissue. i. Grab both limbs of the suture, and pull in opposite directions, locking the knot. j. Continue tying alternating hitches to complete your knot. Endoloop: An endoloop is a pre-tied knot (two parallel hitches) attached to a disposable slip-knot pusher. It provides a simple way to ligate tissue without the need for intracorporeal tying. A common situation in which an endoloop is used is securing a cystic duct that is too large and/or inflamed to be secured with a 10mm clip. Please remember-any cystic duct too large to be encompassed by a 10mm clip may be the CBD!!! Consider this before ligating it. Also remember, the converse is absolutely not true: any duct small enough to be encompassed by a 10 mm clip may still be the CBD!!! It is important to remember that once cinched down, endoloops are difficult to safely remove-be sure you are happy with where your knot will go down before tightening it! In other words, do not pass-point with your endoloop device. a. Insert the endoloop in the abdomen through a trocar using your right hand. b. Break the plastic end of the endoloop outside the abdomen c. Pull on the plastic end of the endoloop, taking up slack on the suture until the loop of suture is approximately 3-5cm in diameter. d. Position the loop near the suture to be ligated (for our purposes, the cystic duct). e. With your left hand and a grasper, pass the grasper through the loop, then grasp the structure to be looped and ligated f. Using your right hand, manipulate the endoloop until the loop sits around the cystic duct at the point you’d like to ligate it. DO NOT PASS POINT with the endoloop! g. Transfer your left hand grasper, still holding the cystic duct within the endoloop, to your assistant. h. Using two hands, and keeping the plastic tip of the endoloop where the knot is exactly at the point you’d like to ligate the duct, barely touching the tissue, slowly draw back on the end of the endoloop outside the abdomen, closing the loop and cinching the knot tight. Rock the knot just a bit to tighten it. i. Withdraw the plastic endoloop device back, exposing the suture, and cut. Extracorporeal tying: All laparoscopic surgeons must be able to tie intracorporeally. Nevertheless, extracorporeal tying is useful when tissues are under extreme tension (closing a wide crural hiatus, for example). This technique utilizes a knot pusher device. Some basic principles: General: 1. Remember: the enemy of laparoscopy is tension; tension on the suture, tension on the needle, tension on the tissues. This critical point may not be obvious in open surgery because you can more easily control tension in an open environment. The lack of haptic feedback prevents you from feeling tension on tissue, needles, and suture as you work with them-it is therefore more difficult to eliminate tension in a laparoscopic environment. Tension on tissue tears delicate tissue; tension on needles as they pass through tissue likewise tears tissue; tension on suture makes tying much more difficult (more on this below). The point of the push- push-pull-pull technique is to avoid putting tension on the tissue through which you are passing the needle. This is accomplished by letting the tissues, rather than you and your instruments, hold the needle. You should be able to pass a needle through the tissue without lifting up on the tissue at all. The same principle holds for tying .You can practice tying without placing tension on the suture in open surgery by tying a two handed knot on a pencil while it lies on a table, without lifting or moving the pencil off the table. Try this- see how much tension you normally put on suture when you tie open? Imagine you are tying a delicate vein during the creation of an AV fistula, or while suture ligating a hemorrhaging intra-abdominal varix- such tear would tear the tissue and foil your efforts! Work to eliminate this by tying without moving the pencil. Finally, practice this same technique in a lap trainer box using laparoscopic tying. 2. Subtle rotations of your instruments will make tissue and needle manipulation, and suturing and tying much easier: remember that it is important that the suture exit your driver at a right angle from the instrument. Simply rotating the instrument 20 degrees will eliminate this angle and make tying harder; conversely, subtle rotations of your instruments will restore this angle and make tying easier. Subtle rotations of accepting instruments will allow them to grasp suture or tissue at right angles rather than parallel, making grasping easier. Experiment with subtle rotations of your instruments as you manipulate needles, suture, and tissue. 3. Practice proper suture management. Keep curls and twists out of your suture as you tie. Tug on the suture to straighten it out; rotate your instruments to eliminate curls. Learn to manage long tails of suture and keep them out of your way. Suturing, Tying: 4. Braided suture is easier to handle in a laparoscopic environment, because it lacks memory. Dyed suture is easier to see than undyed suture. Coated vicryl tends to absorb less fluid, while silk has a tendency to become soggier. On the other hand, silk tends to hold a knot better than vicryl because it is not coated. If you are able to slip your knots, this should not be an issue. In most (but of course not all) situations, 2-0 suture is preferable to 3-0, which may be easier to break because of the lack of haptic feedback I prefer coated dyed 2-0 vicryl for most purposes. A caveat: monofilament suture slides through tissue more easily. When performing a running suture through a length if tissue, it may be easier to pull up on the suture at the end and tighten the suture line if monofilament is used. Using braided suture in this situation requires that your assistant follow your suture as you go, maintaining tension on the suture line the entire time. This is certainly possible, but some prefer monofilament for such purposes. 5. The most common mistake made in early suturing is making large wide movements with your instruments. This puts tension on the suture and the tissue, and causes you to tear tissue and makes it more difficult to loop suture around instruments. This is why we touch the knot will go down before we begin to tie: it reminds us to keep our instruments within 5-10 mm of this point, eliminating tension on the suture as we tie. 6. Suture should generally be cut 6-7” long for most purposes. When tissue is under tension, longer suture may be necessary. Proper suture management (see below) becomes important with longer suture. 7. Imagine a plane extending vertically through your operative field at the knot, dividing the screen into right and left sides. Do not allow your left hand instrument to cross this plane and pass more than 5-10 mm across to the right; do not allow your right hand instrument to pass more than 5-10 mm across to the left. 8. Remember, you can get away with breaking these rules when the tissue is tough and the situation easy. When you are suturing delicate tissue in a difficult situation, however (a bleeding vein, an esophageal perforation, suboptimal trocar position), tension on the needle as it passes through eh suture will tear the suture (more bleeding, a larger perforation). This is when tying without tension on your needle, suture or tissues is critical.
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