During epidural anesthesia, do resistance test, why does the syringe rebound when there is no resistance?

Epidural anesthesia is epidural nerve block anesthesia.

The operation method is as follows:

(1) Lying on the side, hug the knee joint with both hands, and press the lower jaw against the chest in a flexed shape.

(2) According to the requirements of the operation, select the intervertebral space between the 10th thoracic vertebrae to the 4th lumbar vertebrae, first perform local anesthesia, and puncture with a spoon-shaped puncture needle. There are two puncture methods: ① pierce into the epidural space perpendicular to the spine, which is called straight puncture; ② pierce obliquely from the paravertebral side, called lateral puncture.

(3) When puncturing, the level passed is mainly judged according to the change of resistance. When the ligamentum flavum is encountered, the resistance increases and it feels tenacious. At this time, take out the needle core, connect the syringe with a small amount of air (or normal saline), and continue to insert the needle carefully. "Empty feeling", use the negative pressure of the epidural cavity to suck the air in the syringe into the cavity, and observe the change of the liquid level at the head of the syringe. If it fluctuates with the change of the negative pressure, it means that it has entered the hard ridge. extramembranous space. If there is no negative pressure and other phenomena, continue to insert the needle. If cerebrospinal fluid is found, it means that it has passed through the epidural space and entered the subarachnoid space, and the puncture fails and should be abandoned.

(4) It has been proved that in the epidural space, the anesthetics are injected in stages. Commonly used anesthetics are 2% lidocaine (also known as xylocaine) or 2% dicaine, plus 0.1% epinephrine 0.1 ~ 0.2mL. Generally, the single dose of lidocaine for adults should not exceed 500 mg, and the single dose of dicaine should not exceed 60 mg. Continuous epidural anesthesia can be administered in divided doses according to surgical requirements. The whole process of anesthesia should pay close attention to the patient's response and changes in the level of anesthesia.

(5) If continuous epidural anesthesia is required, first take a ureteral catheter corresponding to the size of the spoon-shaped needle, test whether it is unobstructed in advance, and measure the length and size. Place the bevel of the spoon-shaped needle upward (or downward, depending on the surgical requirements), and insert the ureteral catheter into the epidural space from the needle cavity. Pull out the needle while slowly advancing the catheter to the epidural space. The catheter can be left in the epidural space for 3 to 5 cm, not too long. Do not take the catheter out of the lumen when pulling out the spoon-shaped needle, and try to inject a small amount of anesthetic about 2 mL from the catheter. Finally, the catheter left outside the body was fixed straight on the back with adhesive tape to prevent prolapse and bending into an angle, so as to ensure the patency of the catheter and the intraoperative administration.

If you have any questions, please contact us. Our company can produce various customized needles, medical needles, puncture needles, hypodermic needles, biopsy needles, vaccine needles, injection needles, syringe needles, veterinary needles, pencil point needle, ovum pick up needles, spinal needles, etc. If you need customized needle products, please contact us. We look forward to your inquiry! The quality of the products manufactured in our factory will surely satisfy you!

Please contact us if you need: zhang@sz-manners.com