1. Learn three knotting methods in surgery.

2. Master the correct surgical knotting skills.

3. Understand the matters needing attention when knotting.

4. Master the methods of thread cutting and surgical thread removal during operation.

Equipment teaching thread (about 50cm long, dyed with two colors in advance, each half long, so as to observe the passing direction of the thread when knotting and check whether the knot is correct after knotting), needle holder, vascular clamp, silk thread coil, thread scissors and dressing bowl.

The first section surgical knot method

The hemostasis suture in operation can not be separated from ligation, and whether the ligation is firm and reliable is closely related to knotting. Knotting is one of the most commonly used and basic operations in surgery, and the quality and speed of knotting will have an important impact on the length, safety and prognosis of patients. Incorrect knotting may lead to loosening, slippage, bleeding or unhealed suture tissue, which will bring pain to patients and even endanger their lives. Therefore, it is a necessary condition for surgeons to master the correct surgical knotting method skillfully.

(1) Tie the knot and send the thread.

There are generally two methods for knotting and thread feeding in surgery, namely, manual thread feeding method and instrument thread feeding method. Hand thread feeding method is suitable for superficial tissue ligation, which means that the knotter holds the thread reel in one hand and bypasses the vascular clamp that clamps the tissue in the other hand to pass the ligation thread to the other hand; Some people also pass the wound vascular forceps to the other hand to clamp the tissue. Generally speaking, right-handed people hold the coil with their left hand; Left-handed people hold the coil in their right hand. Instrument thread feeding method is suitable for deep tissue ligation, which refers to the method that one end of the silk thread is clamped by a vascular clamp before knotting, and the thread end of the clamp bypasses the vascular clamp that clamps the tissue and is handed to the other hand for knotting; You can also pass the vascular clamp with the line around the vascular clamp that clamps the tissue to the other hand, so that both hands can hold the two ends of the line and tie the knot. After thread feeding, it can be divided into cross-line feeding and non-cross-line feeding according to whether the two ends of the ligature intersect. When giving birth across the line, first tie a single knot with your right finger, and then tighten the ligature directly with your hands without crossing. If the lines do not cross, tie the first single knot with the middle finger of the right hand. After the knot is tied, you need to cross your hands to tighten the ligature.

(2) the classification of knots

Clinically, according to the morphology of nodules, they are usually divided into the following categories:

1. Hemiknot is the basic part of surgical ligation, which is easy to loosen and untie. It is only used for temporary occlusion, such as retrograde cholecystectomy to temporarily block cystic duct, but it cannot be used for permanent ligation alone.

2. Flat knot is the most commonly used knot in surgery, because it is firm after ligation. It is formed by overlapping two single knots in opposite directions, which is suitable for ligation and various sutures of less tissues or smaller blood vessels.

3. Three knots or extra half knots repeat one or more single knots after completing the square knot to make the knot stronger. It is suitable for ligation of blood vessels with important diameters and tissues with high tension after suture. When tying a knot with a thread that is easy to loosen, such as catgut thread or chemical synthetic thread, it is usually necessary to tie multiple knots.

4. Surgical Knot (Surgical Knot) When making the first knot, the ligature is wound twice to increase the contact area and friction between the lines, and it is not easy to loosen or slip when making the second knot. Because it takes time to tie this knot, it is only suitable for ligating large blood vessels.

5. False knots are composed of two simple knots in the same direction, which are easy to slip after ligation and should not be used.

6. Slipknot Although its knot structure is similar to a flat knot, the operator's hands are uneven when tying the cable, one is tight and the other is loose, and even one side line is tightened and tied with the other side line, so the finished knot is not a flat knot but a slip knot that is easy to loosen, so special attention should be paid to avoid it when operating.

(3) Knotting method The knot can be knotted by hand or with the help of instruments. Hand knotting is commonly used in surgery, which can be divided into two-handed knotting and one-handed knotting. According to the different habits of operators, one-handed knots can be divided into left-handed knots and right-handed knots. The instrument knot is tied by means of needle holder or vascular clamp, also known as clamp knot method.

1. One-handed knotting is a simple and quick method, which is easy to learn and understand, and is widely used in surgery. You should master and practice. Right hand knot and left hand knot.

2. Double-hand knot method is convenient, firm and reliable, which can be used for general ligation and suture ligation with great tension in deep or tissue.

3. The method of tying a knot with pliers is to tie a knot around a long line and a short line with vascular forceps or needle forceps, which is called the pliers knotting method. Can be used for superficial and deep ligation. Vascular clamp or needle holder clamp is not only an extension of thread, but also an extension of operator's hand. This method is suitable for ligation when the thread end is too short, it is difficult to tie the knot by hand or the knot space is narrow. Sometimes it is also to save sewing and threading time.

(4) Precautions for knotting 1. No matter how you tie the knot, the directions of two adjacent simple knots must be opposite, otherwise it is easy to fake the knot and become loose.

2. When tying a knot, the three points of both hands and the ligation point should be in a straight line. If the three points are connected at a certain angle, the ligature will easily fall off when forced to tighten. When tying a knot, both hands should apply force evenly. If a hand is tight-a hand is loose, it is easy to slip into a knot and slip off.

3. According to the depth of the knot and the object of ligation, choose the ligation line with appropriate length and thickness. Soaking in salt water before knotting can increase the toughness and friction of the thread, which is easy to tighten and not easy to break. When tying a knot, you must tie it tightly along the direction of the thread, otherwise it is easy to break the ligature.

4. When tying a knot in a deep place, it is difficult for both hands to get close to the ligation place at the same time because of the narrow space. At this time, you can pull one end of the thread with one hand after knotting, and the other end of the thread can be reversed near the knot with the fingers of the other hand, so that the knot can be tightened evenly. In the case of tissue ligation with high tension, the first knot usually loosens when the second knot is tied. At this time, after tightening the first knot, the assistant can hold the knot with toothless tweezers and then take off the tweezers when tightening the second knot.

5. The purpose of ligation is to close the lumen or abnormal opening and prevent the contents from moving further. For example, the ligation of bleeding point is to close the broken end of blood vessel and prevent bleeding; High ligation of hernia sac is to close the hernia door to prevent the hernia contents from coming out; Vasectomy is to stop the movement of semen. Take the ligation of bleeding point as an example: ligation can be started after the bleeding point is clamped. The assistant first erected the vascular clamp so that the operator could bypass the wire, and then put down the vascular clamp so that the tip was slightly inclined. After the first knot is tied, the assistant will continue to tie the knot while loosening the vascular clamp, then tie the second knot to form a flat knot, and then cut the thread.

Intraoperative thread cutting is to cut the remaining suture after suture or ligation, which is usually done by an assistant. The novice cut the thread. After tying the knot, the knotter pulls the tail of the double thread together and leans slightly to the left. The assistant holds a slightly opened thread trimmer in his left hand. "Slide, slide, slant and cut": Slide the proximal tip of the scissors down along the suture to the upper edge of the knot, then tilt the scissors up at an appropriate angle, and then cut the suture. The greater the inclination angle, the longer the thread left; The smaller the angle, the shorter the remaining line. Generally speaking, when the thread is cut at an inclination of about 45, the remaining thread ends are moderate (2~3mm). Attention should be paid to the ligation of deep tissue, large blood vessels and catgut or nylon thread. The thread ends should be slightly longer, such as silk thread 2~3mm, catgut thread 3~5mm, steel wire 5~6mm, the two broken ends of steel wire should be tightened, catgut thread or nylon thread 5~ 10mm, and leather suture 0.5~ 1cm. A knot with a short thread is easy to slip off, and a knot with a long thread will cause the tissue to react to foreign bodies in the thread.

Section 3 surgical suture removal

It is only necessary to remove the skin suture, so surgical suture removal refers to the surgical process of removing the suture after the sutured skin incision heals or when some complications occur in the surgical incision (such as suppurative infection of the incision, subcutaneous hematoma compressing important organs, etc.). ). When removing stitches, be careful not to let the line segment originally exposed outside the skin pass through the subcutaneous tissue to avoid bacterial contamination. The time of suture removal should be determined by considering the incision site, local blood supply, patient's age and nutritional status, incision size and tension. Generally speaking, the head, face and neck incisions are removed 4~5 days after operation; Lower abdomen and perineum for 6~7 days; Chest, upper abdomen, back and buttocks for 7~9 days; Limbs 10~ 12 days (it can be appropriately extended near joints); Tension reduction suture 14 days. Sometimes you can use interval needles first; The suppurative wound should be removed immediately; Teenage patients can shorten the suture removal time appropriately; Elderly, malnourished and diabetic patients can delay the time of taking out stitches. The specific method of thread removal is to disinfect the incision area according to the dressing change method, gently lift the knot with tweezers in the left hand, insert the slightly opened tip of the thread cutter into the gap between the knot and the skin in the right hand, and cut the thread flat on the skin at the eye of the needle, and then gently pull the suture to the cutting side quickly to avoid opening the incision and causing discomfort or subcutaneous pollution to the patient. Finally, the incision was disinfected with alcohol cotton ball, and then covered and fixed with sterile gauze and adhesive tape.