I. What is central vein? The central vein is the large vein close to the heart, mainly the internal jugular and subclavian veins bilaterally.
Why should we do central venipuncture?
1.Rapidly open the large vein channel to facilitate the smooth implementation of resuscitation treatment such as infusion and blood transfusion. It is often used in emergency and critical patients’ resuscitation treatment, and it is common in emergency department and resuscitation treatment.
2.Monitoring the pressure of central vein and guiding the input of clinical fluid. Used in patients in shock and in patients undergoing surgery.
3.Used in medium and large surgical patients, because of prolonged fasting, when longer fasting is needed in order to perform intravenous nutrition therapy.
4.For the placement of temporary or permanent pacemakers, often used in patients with cardiac arrhythmias.
5.Phlebography or transvenous interventions: such as hemodialysis or blood replacement filtration (hemofiltration), placement of venous stents, etc.
6.Tumor patients are often treated with chemotherapy through central vein, in order to protect peripheral blood vessels and prevent skin necrosis caused by extravasation of chemotherapy drugs.
Third, the risk of central venous puncture and catheter placement.
We all know that there are risks associated with any medical operation, and the specific type of risk is related to the site you are operating in. The anatomical diagrams of the internal jugular and subclavian veins show that both are at the apex of the lung at the top of the chest cavity, the arteries and veins are in close proximity to each other and to the heart, etc. Therefore, the following risks can occur when operating here.
1, pneumothorax, air embolism: when the heart is in diastole and the thoracic cavity with to the heart and thoracic cavity pressure is lower than the external atmospheric pressure and become negative pressure state, the external air is easy to enter the thoracic cavity and heart and produce pneumothorax and air embolism (pulmonary embolism). This is a fatal risk and can be life-threatening once it occurs.
2.Local hematoma, hemothorax, local infection, sepsis: If the patient has poor coagulation function or mistakenly punctures the artery, hemothorax and subcutaneous hematoma will be formed because of high arterial pressure or blood does not easily coagulate into the chest cavity or subcutaneous, and infection will occur over time, leading to sepsis.
3. Unsuccessful puncture: Unsuccessful puncture can be caused by local anatomical variation or inappropriate body position or inappropriate selection of puncture points and needle angles, while multiple punctures at multiple points and angles can increase the chance of the above-mentioned risks. Therefore, it is not recommended to perform multiple punctures at multiple points and multiple angles at the cost of increasing the risk of the above-mentioned risks, and sometimes it is easier to perform the puncture by a different person without increasing the risk.
As we can see from the above, this is the content of the preoperative consent form for central venipuncture. By analogy, the same can be said for the risks associated with other medical procedures. I believe that no physician would intentionally exaggerate the risks of a procedure such as puncture, and no physician would have the leisure to create an alarmist document to scare patients and families.
Which physicians should master central venipuncture?
Central venipuncture is a very important specialty puncture, especially when it comes to emergency patients, this central venous catheter will become a life-saving catheter. Therefore, I believe that emergency physicians, internists, surgeons, obstetricians and gynecologists, and anesthesiologists should all be proficient in central venipuncture techniques. However, because of the high risk involved in this operation, many hospitals, including some very prestigious large hospitals, only anesthesiologists can perform this technique, whereas I believe that: anesthesiologists who perform the operation after anesthesia is completed have a greater risk because the patient is anesthetized and loses sensation, and all will not know if there is a pneumothorax or hemothorax, which eventually results in the loss of function of one lobe of the lung during the entire operation. Therefore, it is very dangerous to perform puncture during anesthesia. In our department, central venous puncture placement is performed one day before surgery for medium and large surgeries. If there is any problem, chest X-ray can be taken immediately to understand the condition of lung and chest cavity for timely treatment. This requires the surgeon to master this technique.
V. The puncture process and what should be noted.
This section should be purely for personal experience, and it is necessary to show it to the doctor. However, as a general public, there is no obstacle to learn more about it. From it, they can learn that there are certain risks associated with any treatment or operation in a hospital, and they can also learn how doctors go about avoiding these risks. I believe that every doctor does this to the best of his or her ability because, if something goes wrong, it is an ominous sign for both the patient and the doctor doing the operation. At this point, both the patient and the doctor are on the same page, never in opposition!
[ft=,+0,][ft=,+0,]1 Preparation of items prior to central venipuncture: a sterilized and approved venotomy kit or suture kit, a bag of heparin saline, a 20 ml syringe, 5 ml of 2% lidocaine, a tee, two heparin caps, a set of single or double lumen mid-surface venous catheters, and skin disinfection items. See the following figure for details.
[ft=,+0,] sterilized venotomy kit or suture kit
[ft=,+0,] One set of single or double-lumen central venous catheters (this is a double-lumen central venous catheter)
[ft=,+0,] Items to be used are neatly arranged in the appropriate location
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[ft=,+0,]2 Flushing of the tube before puncture: Before puncture the assistant should put on a mask, cap, and sterile gloves, open the venotomy bag, and place the items to be used neatly in their proper place. The central venous catheter must be flushed with heparin saline and then clamped closed, especially for double-lumen tubes, otherwise gas can enter the vessel through the tube and form an air embolism. When taking a new puncturer, the first step is to make him very proficient in preparing the items and flushing the tubing. The flushing tube is shown in the figure below.
[ft=,+0,] Flushing the various tubes with heparin saline and clamping the double lumen
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[ft=,+0,]3 Patient position during puncture: Whether it is an intracervical or subclavian puncture, the patient’s position is often the key to successful puncture, but this step is generally not taken seriously. The position of the patient is supine with the pillow on the back of both shoulders and slightly higher on the punctured side. The above is what is written in general textbooks. However, when it comes to my puncture, I am extremely strict about the position, and I have some experience that I can share with you: the small pillow is not a normal pillow, but a patient’s shirt turned into an axis, tucked between the patient’s two scapulae and biased towards the puncture side, the patient goes to the pillow, so that the head is naturally tilted back and the thorax is extended (similar to our normal chest expansion), this position helps the clavicle to spread upward and the blood vessels to retreat backward. Because there is a layer of fascia when the subclavian vein meets with the clavicle, the clavicle moves forward while the vessel moves backward, and under the pull of the fascia, the subclavian vein moves forward with the clavicle, which provides a good position for puncturing the subclavian vein. This provides us with a good position for puncturing the subclavian vein. The certainty of successful puncture is greatly improved. The patient position is shown in the following figure
[ft=,+0,] Patient supine with pillow removed
[ft=,+0,] while using the patient’s top turned into an axis
[ft=,+0,] with the patient’s shirt turned into an axis, tucked between the patient’s scapulae and biased towards the punctured side
[ft=,+0,] The patient is decubitized so that the head is naturally tilted back and the thorax is extended
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[ft=,+0,]4 Subclavian and internal jugular vein puncture point, puncture direction, and angle at puncture: just as we have described the importance of puncture position, it is equally important to choose the puncture point, puncture direction, and angle at puncture. Our aim is to have a high rate of successful puncture and to avoid complications of puncture as much as possible. The selection of the puncture point of the subclavian vein: the textbook says that this point is 1 cm lateral to the midpoint of the clavicle, my experience is that the outer side of the midpoint is as far away from the clavicle as possible, so that the angle of needle entry is flat, because the artery and the pulmonary tip are posteriorly displaced, as far as possible the horizontal direction of puncture, the possibility of accidentally penetrating the artery and the pulmonary tip is small. The direction of the needle is straight to the right sternoclavicular joint, first horizontal needle, the tip of the needle to the clavicle after a slight backward and slightly elevated needle tail again into the needle close to the lower edge of the clavicle into the clavicle and the first rib space after the needle tail downward pressure so that the needle center may remain horizontal and then continue to enter the needle, while the needle into the syringe back, if there is a slightly dark red smooth blood return indicates that the subclavian vein has been entered. The entire puncture procedure and precautions are described below in photographic text.
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[ft=,+0,] Body surface markings, location of puncture point, direction and angle of needle entry during internal jugular and subclavian vein puncture
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[ft=,+0,]Sterilize the operative area, including the subclavian and internal jugular puncture sites, and switch to the internal jugular puncture site after preventing an unsuccessful subclavian puncture. Repeated punctures at one site should never be performed, as this will reduce the occurrence of complications.
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[ft=,+0,] Extract the anesthetic and remember to check the drug, concentration.
[ft=,+0,] Local anesthesia, from the puncture site skin subcutaneously up to the first rib space under the internal lock.
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[ft=,+0,]Incision of the skin subcutaneously at the puncture site.
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[ft=,+0,]The direction and angle of the puncture needle entry, remembering that the bevel of the puncture needle should face downward to facilitate the smooth entry of the guidewire into the superior vena cava. Sometimes, because of the wrong bevel, the guidewire enters the ipsilateral internal jugular vein or the contralateral subclavian vein, which has happened to us and does not affect the infusion, but the measured central venous pressure is inaccurate.
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[ft=,+0,]Pump back the syringe while feeding the needle, if there is a slightly dark red unobstructed return it indicates that it has entered the subclavian vein.
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[ft=,+0,]Place the guidewire from the side hole of the puncture needle, there is a scale on the guidewire, when there are three black dots on the guidewire at the side hole of the puncture needle, it means that the guidewire has entered 30cm, at this time, pull the needle outward.
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[ft=,+0,]Insert the dilatation tube along the guidewire
[ft=,+0,]Insert the central venous catheter with the guidewire to a length of 15 cm. If you are not sure whether it is an artery or a vein, you can release one side of the catheter and observe the flow of water, if the blood gushes outward, it means it is an artery, if the water surface shrinks inward, it means it is a vein, because the artery pressure is high, while the central vein is mostly under the negative pressure of the heart and chest cavity, the pressure is low, and the water surface is shrinking back toward the heart. Just be careful not to let the gas in.
[ft=,+0,]Pump back the double lumen catheter, and when it can return blood smoothly, it is correctly placed.
Install the tee or heparin cap. Be careful not to let any air in during installation.
[ft=,+0,]Evacuate air from the tee and catheter
[ft=,+0,] Suture the catheter in place
[ft=,+0,] Covering the dressing and fixing the catheter The subclavian catheter is more discreet and does not affect the movement and appearance. Therefore, I am used to perform subclavian vein puncture. If it is unsuccessful, I change to internal jugular vein puncture, and if it is unsuccessful again, I have to do femoral vein puncture reluctantly. In conclusion, it is important to open the venous access and only secondly to be able to measure the central venous pressure. The above is only personal experience, and can be learned when approved. Those who do not recognize it, just look at it. Thank you for reading. Please correct me if there is anything wrong.
This is an article written by a surgeon, which is very useful for us anesthesiologists, and also some personal views.
As the author said, the general pad should be under the scapula to stretch the shoulder completely, and the head should not be too far to the left, otherwise the pediatric vein will be easily covered by the artery.
2.My custom is to start with the internal jugular, from top to bottom, then the subclavian, and finally consider the femoral vein. The subclavian vein is fixed and relatively easy to pierce, but it also has a low rate to the superior vena cava, sometimes the central venous pressure is not measured correctly, and the catheter is easily clamped when the sternum is propped open during open-heart surgery. I usually choose subclavian, while most adults choose intraclavicular. Of course, in order to facilitate the care and fixation of surgical punctures, more subclavian is chosen.
3.I generally do not locate the puncture point for intracarotid puncture, I feel the arterial pulsation slightly lateral to the needle, the tip of the needle points to the right nipple. In adults, the distance to the outside is slightly larger, while in children, the needle should be inserted close to the arterial pulsation.
4, central venous puncture must be closely monitored in the vital signs, puncture in the detachment, tracheal catheter fracture, guide wire too deep into the right atrium resulting in frequent ventricular premature. Be careful.
5.Personally, I disagree with the author’s view that he does not advocate puncture in the operating room, because puncture after anesthesia in the operating room is more secure for patient safety. In contrast, puncture in the ward is subject to more disturbing factors, and it is more difficult to resuscitate in case of other dangerous situations.