The trachea is located in the middle of the neck and its upper section is shallow, about 1.5-2 cm from the skin; the lower section becomes deeper and is about 4-4.5 cm from the skin at the upper border of the sternum. the front of the trachea is covered by the skin, subcutaneous tissue, superficial fascia and the broad jugular muscle. Between the superficial fascia and the broad jugular muscle, there are many small veins (anterior jugular plexus) that converge into the anterior jugular vein. The deeper layer of the latissimus dorsi muscle is the superficial deep fascia, which surrounds the anterior cervical muscles on both sides and joins them in a white fascial line at the midline. Behind the superficial layer of deep fascia is the pre-tracheal fascia and trachea of the middle layer of deep fascia. The anterior tracheal fascia is attached to the anterior wall of the trachea. The thyroid gland is located on both sides of the trachea, and the thyroid isthmus is located in front of the 3rd and 4th tracheal rings and is surrounded by the pre-tracheal fascia, which should be pushed upward or cut off during surgery before cutting the trachea. The lowermost artery and vein of the thyroid gland and the thyroid plexus are located on both sides of the trachea, and the main blood vessels of the neck are located outside the trachea. Therefore, when performing a tracheotomy, the incision must be made within the safety triangle of the neck (the two upper corners of the triangle are each located at the junction of the cricoid cartilage and the sternocleidomastoid muscle, and the lower corner is located at the midpoint of the sternotomy).
Indications
1, acute and chronic laryngeal obstruction such as acute laryngitis, diphtheria, laryngeal edema, pharyngeal tumor, scar stenosis, etc.
2.Respiratory difficulty caused by the retention of respiratory secretions cranial trauma, intracranial or peripheral nerve disorders, tetanus, respiratory burns, major thoracic and abdominal surgery caused by cough, hypospadias or laryngeal paralysis.
3, pulmonary insufficiency severe pulmonary heart disease, poliomyelitis, etc. resulting in respiratory muscle paralysis.
4.Laryngeal trauma, maxillofacial pharyngeal obstruction of the upper respiratory tract after major surgery.
5.Foreign body in the respiratory tract, which cannot be removed through the mouth.
Pre-operative preparation
1.Obtain the consent of the family and explain the necessity of surgery and possible accidents.
2.Prepare surgical lighting, suction, direct laryngoscope and tracheal intubation.
3.Select a tracheal tube suitable for the thickness of the patient’s trachea, including an outer tube, an inner tube and a trocar core.
Anesthesia
Generally apply 1% procaine local anesthesia. When tracheal puncture is made after revealing the trachea, anesthesia of the tracheal mucosa can be performed by dropping 1% to 2% dicaine 0,2 to 0,3 ml into it. In case of emergency or when the patient is in a coma, anesthesia can be dispensed with.
Surgical steps
1, position supine, flat and under the neck pillow, and maintain the posterior cervical supine position, the head is in the middle, the condition does not allow the use of semi-sitting position.
2.The incision is made in the midline of the neck, starting from the lower edge of the thyroid cartilage and ending one finger above the upper sternal incision.
3.Cut the subcutaneous tissue and cut the subcutaneous tissue of superficial cervical fascia and broad cervical muscle to the anterior cervical muscle. The incision is pulled symmetrically to both sides with small pulling hooks, and the larger superficial veins in the subcutaneous tissue are ligated and cut one by one. In patients with respiratory distress, these small veins become thickened in anger and must be ligated to avoid intraoperative bleeding that may interfere with the procedure. After exposing the anterior cervical muscle, the white line is cut longitudinally.
4.Pull open the isthmus of the thyroid gland by probing the trachea with the fingers and separating it downward, and then the light red, soft isthmus of the thyroid gland is visible upward. For larger isthmus, two curved hemostatic forceps can be used to cut off the isthmus after clamping, and the tracheal ring can be seen. The pre-tracheal fascia, suprasternal fossa and paratracheal tissue need not be separated too much to avoid mediastinal emphysema or pneumothorax. If there are small blood vessels in front of the trachea that prevent tracheotomy, small gauze balls with hemostatic forceps can be used to gently push the small blood vessels to one side to make them leave the front of the trachea; if there are bleeding points, they should be ligated to stop bleeding.
5, cut the tracheal ring with a sharp knife in the anterior midline of the trachea to cut the 3rd to 4th (or 4th to 5th) cartilage ring of the trachea, the knife blade should face upward when cutting, from the bottom upward to pick open, the knife tip should not pierce too deep, 2 to 3mm is appropriate. When coughing, the anterior wall of the esophagus together with the posterior wall of the trachea can be squeezed into the tracheal lumen, therefore, it should be cut quickly during the inspiration process when the coughing sound has just stopped.
6.Insert the tracheal cannula after cutting the cartilage ring of the anterior tracheal wall, that is, use the curved hemostatic forceps or tracheal cannula dilator to widen the tracheal incision, and then insert the cored tracheal cannula. If the patient has a strong cough, the core should be pulled out immediately and the endotracheal secretions and bloody fluid should be aspirated with a suction device, and then the endotracheal tube should be inserted. After confirming that the cannula has been inserted into the trachea, the pull hooks on both sides can be removed; if there is no gas in or out, the tracheal cannula should be pulled out. Repositioning.
7.Treatment of incision The incision mostly does not need to be sutured. If the incision is too long, 1 to 2 stitches can be closed at each of the upper and lower ends, but not too tightly to avoid subcutaneous or mediastinal emphysema. The area around the incision is covered with oiled gauze tape, a small gauze with a small cut between the incision and the trocar (3 to 4 layers are sufficient), and finally the fixation band is wrapped around the back of the neck and tied in a knot on the side of the neck. The knot should be tied loosely or tightly; if it is too loose, the cannula will easily slip off and cause asphyxia; if it is too tight, if it is locally swollen after surgery, it may affect the venous return of the head. If the cannula with air bag is applied, about 3ml of air is injected from the air injection tube, and then the air injection tube is folded and tied with thread to ensure that there is no air leakage during artificial respiration.
Intraoperative precautions
1, because of the seriousness of the disease, does not allow delay, and there is no tracheotomy apparatus, without sterilization and anesthesia, use the daily physiological knife to cut the pre-tracheal skin, subcutaneous tissue and cervical white line, use the finger to probe to the tracheal ring, and use the finger as a guide to cut the tracheal ring. Then, the knife handle is inserted into the trachea, turned at an angle to support the tracheal incision, and a common rubber catheter is then inserted. Its outer end is cut into two flaps, and the flap end is cut with a hole, and the Ankouan band is separated to both sides in place of the tracheal cannula. After the wound is padded with oil gauze and small gauze around the wound, the fixation band is fixed around the neck.
2. During surgery, the patient’s head position should be maintained in a median posterior position. Keep the incision in the midline of the neck. It should not be dissected to the sides. Explore the position of trachea at any time during the operation to guide the direction and depth of separation.
3, the pulling hook is put into the pulling when the separation is deep, and for each layer of dissection, both sides of the pulling hook are moved to pull a deeper layer at the same time, and the pulling force on both sides should be even, so as to avoid uneven pulling force and pulling the trachea to one side. When separating to the anterior wall of the trachea, the pulling hook should be pulled outward and forward, not backward, so as not to compress the trachea. When the tracheal cartilage ring has been cut and the tracheal cannula has not been inserted, special attention should be paid to not disconnecting the hook to avoid increasing the difficulty of intubation.
4, the pre-tracheal fascia should not be separated, but can be cut at the same time with the anterior tracheal wall. The lateral wall of the trachea should not be separated, otherwise it is easy to injure the pleural roof or mediastinum, which can also cause the tracheal incision to deviate to one side and cause difficulties in extubation.
If it is too high, it is easy to injure the first cartilage ring, which will cause laryngopharyngeal stenosis; if it is too low, it is easy to make the trocar come out or top the rongeur, which will cause mucosal injury and bleeding, or cause mediastinal emphysema, or even injury to the large blood vessels in the chest. The right pleural roof is higher in children, so pay attention to prevent injury.
6. Intraoperative hemostasis should be perfected and the skin should not be sutured too tightly to prevent the occurrence of hematoma or emphysema.
Postoperative treatment
1. Keep the room clean, with fresh air, temperature at about 22°C and relative humidity at about 50%. Change two layers of wet saline gauze daily to cover the trocar opening to prevent dust and foreign body inhalation and dry scab formation.
2.Add antibiotics, alpha chymotrypsin and steam inhalation to the trachea for 15 minutes as needed, 3 to 4 times a day. Position should not be changed excessively. When turning over, keep the head, neck and trunk rotated in the same axis to avoid irritation or breathing difficulties caused by casing activity or dislodgement. If a pediatric or delirious patient is likely to remove the cannula by himself, fix his arm.
3. Pay close attention to the presence of respiratory distress, increased respiration and resistance, bleeding in the cannula, etc., and promptly find the cause and deal with it.
4.Extract the cannula as soon as possible after the breathing and gas exchange volume are resolved. Note before extubation.
(1) First block 1/2 of the orifice with cork or tape, if there is no respiratory distress, further block 2/3 until all blocked for 1 to 2 days without respiratory distress, you can pull out the tube. The cork or tape must be fixed with thread on the fixing band of the tracheal tube to prevent being inhaled into the trachea.
(2) If a tracheal tube with air bag is used, the air bag should be drained first and then the tube should be blocked.
(3) Prepare a set of tracheotomy instruments before extubation in case of reintubation in case of respiratory distress after extubation.
Suck out the endotracheal secretion before extubation, then loosen the fixation band and slowly pull out the tube with the curvature. In case of respiratory distress, another sterile cannula should be inserted immediately through the original incision. After extubation, the wound does not need to be sutured, and can be wrapped with oil gauze, or the wound can be pulled together with butterfly tape.