In the past 10 years or so, implantable infusion pumps have been widely used abroad, greatly reducing the labor intensity of nursing staff and reducing complications associated with infusion, chemotherapy, and blood collection. It also greatly reduces patients’ pain, especially for those who need repeated infusions, chemotherapy, obesity, and pediatrics have its clinical value. A central venous system with subcutaneous access is completed by central venous placement, which is then connected to a special pump body and placed under the skin, and it provides both a safe and convenient intravenous route for patient chemotherapy, rehydration, nutrition and blood collection. Our hospital has been applying this technology since June 1999, especially placing implantable IV pumps for pediatric oncology patients, and has achieved good results. 1.Comparison of currently used vascular access device systems Among the current vascular access devices, three are most commonly used: implantable intravenous infusion pump (Port), deep venous puncture placement (Hiekmen) and central venous cannula (PICC) inserted through peripheral veins. Both Hiekmen and PICC are end-opening catheters with a relatively short maintenance time of weeks to months and require a high level of care for the exposed tubing; Hiekmen and PICC avoid painful punctures; PICC is a central venous catheter inserted through a peripheral vein, which is punctured through the median elbow vein, noble vein, and cephalic vein at the elbow It is usually used for patients treated with intravenous fluids for more than 7 days. It is soft, easy to bend, durable, and does not cause thrombosis, making it suitable for prolonged use. It is clinically proven to stay in place for greater than three months (up to one and a half years has been reported abroad), avoiding repeated punctures, while central venous catheters are typically left in place for only two weeks. It uses intuitive placement, just like an ordinary infusion puncture, without local anesthesia, without stitches, simple, safe and fast operation, high success rate, reducing patient pain, and after the patient is placed in PICC, the arm movement is not restricted, and he can even take a shower. Based on the above advantages, PICC has become a safe and economical alternative to central venous catheters and is widely used in clinical practice. At present, our department mainly provides the placement of difficult-to-place PICC for the nursing central venous center, and adopts the interventional method to place some patients with poor venous conditions and failed bedside placement, and the success rate is as high as 98%. However, PICC will have a small section exposed outside the skin, which is more likely to be infected, and it is not easy to take care of, so you have to go back to the hospital every week to maintain the tube to avoid blockage or inflammation, and it is generally best not to place it for more than six months! The IV port is an intravenous infusion device that can be completely implanted in the body, mainly consisting of an injection block for puncture and an intravenous catheter. It provides a reliable intravenous access for patients who need long-term infusion treatment, and is used for infusion of various drugs, rehydration, nutritional support therapy, blood transfusion and blood sample collection. The advantages of the implantation can be retained for a long time (8~10 years), reduce the pain and difficulty of repeated venipuncture, deliver drugs directly to the central vein through the catheter, ensure that chemotherapy for tumor patients is carried out in a planned, timely and accurate manner, prevent damage to peripheral veins from irritating drugs, protect blood vessels, and reduce local tissue necrosis and other adverse reactions. The implantable intravenous infusion pump (Port) buries the drug delivery pump under the skin, bringing convenience to patients in their daily lives. It can be placed for years or decades and has less chance of causing secondary infection. 2, the structure of the implantable intravenous infusion pump One part is the injection seat, which is topped with a puncture septum made of liquid silicone to ensure thousands of punctures without leakage, and the other part is the silicone catheter for radiographic development, and the two parts are connected by a catheter lock. The pump body is available in different materials with different catheter sizes and types. The catheter is also available in different thicknesses and has a size scale on the surface. 3.The choice of catheter placement route Central venous placement is most common in the upper vena cava. Because the vena cava is thick, the fluid flow rate is fast, and the input fluid is quickly diluted by the blood, which does not cause irritation to the vessel wall and is not limited by the concentration and speed. Commonly used routes of intravenous catheter placement into the superior vena cava are: via internal jugular vein, supraclavicular vein, subclavian vein puncture placement and external jugular vein incision placement. (1) There are various methods of cannulation of the internal jugular, subclavian and femoral veins. Successful cannulation, whether through the internal jugular vein route or through the subclavian vein route, depends on a thorough understanding of the neck anatomy. The internal jugular vein is located at the apex of the triangle formed by the head of the sternocleidomastoid muscle and the clavicle. The subclavian vein passes directly below the midpoint of the clavicle. In cases where it is difficult to identify the markers for one type of cannulation, an alternative route should be considered. The patient should be evaluated for factors that may make cannulation more difficult, such as a history of failed cannulation or the need to cannulate a site with previous surgery, skeletal deformity, or scar formation. When intubation is expected to be difficult, patient safety should be paramount and intubation should be performed by or under the supervision of an experienced physician. (2) Internal jugular vein cannulation may be difficult in obese patients, in whom neck markings are often obscured. Subclavian vein cannulation should be avoided in patients with severe hypoxemia, as such patients are likely to have pneumothoracic complications when cannulation is performed at this site and are less able to tolerate pneumothoracic complications. Intravenous cannulation should be avoided in patients with severe contamination in the inguinal region because of the higher risk of catheter-related infection in these patients when the femoral vein is cannulated. If a patient requires central venous cannulation for shock resuscitation, then femoral vein cannulation should be considered for the reason that cannulation at this site is faster to operate. (3) After puncture placement into the superior vena cava, the end of the catheter must be clamped with a mosquito clamp to prevent air from entering and forming an air embolus. Under X-ray fluoroscopy, the catheter is placed into the superior vena cava. The pump body is then buried subcutaneously in the anterior axillary line between the 5th and 6th ribs of the chest wall, and the jugular catheter or subclavian catheter is connected to the pump body via a subcutaneous tunnel. The pump body is secured with sutures to the chest wall fascia to prevent movement. When the pump body is placed under the skin, there should be a 0.5 cm fat layer with uniform thickness between the skin and the pump body, otherwise the pump body will be easily deflected and affect the injection. At the same time, the pump body cavity put in is basically similar to the size of the pump body, so that the subcutaneous tissue can be used to fix the pump body and prevent it from turning over. If the separated cavity is too large, 2 needles can be fixed around the pump body. The subcutaneous cavity should be separated bluntly and without violence to avoid local bleeding causing infection. To prevent catheter obstruction, on the one hand, the catheter should not be placed at an angle during surgery, and on the other hand, the catheter should be closed with light heparin every time the chemotherapy drug is infused, that is, the catheter should be flushed with 5ml~10ml of heparin solution containing 2.5U/ml, and blood should be pumped back and then the chemotherapy drug should be infused, and then closed with light heparin. When pulling out the needle, flush while pulling to counteract the pressure of blood return at the moment of pulling out the needle, and secondly, it must be flushed once a month during the interval of treatment. 4.Common complications Among the most common complications after central venous cannulation, most of the recent complications are caused by improper operation, mainly pneumothorax, pneumothrombosis and mediastinal hematoma. Pneumothorax mostly occurs in subclavian puncture placement with an incidence of 3%. In children, pneumothorax can be caused by improper operation after opening the vein, and the possibility of pneumothorax has been reported to increase when operated under non-general anesthesia. Mediastinal hematoma can occur after internal jugular vein puncture and injury to the arterial and venous walls of the neck. Placing the patient in a low head position during opening or puncture of the neck vessels and ensuring that the catheter is filled with saline at all times during intubation reduces the occurrence of air embolism. The choice of general anesthesia is also a factor in reducing air embolism formation. Long-term complications after catheterization include infection, catheter displacement, catheter rupture, thromboembolism and catheter occlusion. 5.Summary In order to reduce the pain and difficulty of repeated venipuncture, people choose implantable intravenous infusion pump (Port), which consists of two parts: the injection seat for puncture and the intravenous catheter, the end of which is located in the central vein, is an intravenous infusion device that can be implanted under the skin and left in the body for a long time. It is designed for patients who require long-term and repeated infusions of chemotherapeutic agents, parenteral nutrition (TPN) or continuous infusion, and can be used for almost all intravenous treatments such as antibiotics, blood products, general intravenous rehydration and blood collection. Infusion access can be established by using a non-invasive needle puncture infusion pump, reducing the pain and difficulty of repeated punctures. At the same time, the infusion pump can deliver various drugs directly to the central vein through the catheter, relying on the local high flow rate and high flow rate of blood to rapidly dilute and disseminate drugs, preventing damage to the vein from irritating drugs, especially chemotherapy drugs and nutrition support drugs.