According to the data of clinical research, the number of new cancer cases per year is more than 3 million, the incidence of cancer has been on the rise, more than half of the cancer patients suffer from different degrees of chronic pain, and the number of advanced cancer patients reaches 75%-90%. Cancer pain is frightening, it not only brings physical pain, but also causes mental torture, which seriously affects the quality of life. At present, cancer pain can be relieved in most patients by rational and comprehensive three-step drug therapy, but in many patients, 10%-20% of the patients with persistent pain still have poor response to the above drug delivery methods, and need to use interventional therapy. Moreover, the use of large doses of analgesic drugs can produce serious and intolerable side effects, such as nausea and vomiting, nephrotoxicity, neuropsychotoxicity, such as drowsiness, delirium, etc., which hinders the application of drugs by traditional routes. Intrathecal drug infusion system is a therapeutic method that uses a drug infusion pump embedded in the patient’s body to infuse drugs into the patient’s subarachnoid space, which acts on the corresponding sites in the spinal cord to block the transmission of pain signals to the brain through the spinal cord, so that the pain signals can not reach the cerebral cortex, thus achieving the purpose of controlling pain. At present, it is recognized as the fourth-step treatment method for cancer pain treatment, which can bring good news to the above-mentioned 10%-20% of patients with intractable pain. At present, the Department of Pain Medicine of Guizhou Provincial Cancer Hospital and Affiliated Hospital of Guiyang Medical University has taken the lead in completing the implantation of intrathecal drug infusion system in 4 cases of patients with intractable cancer pain in the province, which achieved good analgesic effects and were successfully discharged from the hospital. Lu Wei, Department of Pain Medicine, Affiliated Hospital of Guizhou Medical UniversityWhat is Intrathecal Drug Infusion System? The implantation of intrathecal drug delivery system is a minimally invasive surgery. Doctors observe the patient’s response to the medication and pain relief through a drug test before the surgery. If the tests are favorable, the entire system is implanted. The doctor will place a catheter into the subarachnoid space of the spinal cord through a puncture guided by imaging equipment. The catheter is then connected to the pump through a subcutaneous tunnel, and the incision is closed to complete the implantation of the entire system. After the intrathecal drug infusion system is implanted, the doctor and specialized technicians will use an extracorporeal programmable controller to non-invasively set and adjust the system so that the patient’s pain can be optimally controlled. Patients return to the hospital for regular refills and follow-up visits. The refill process is simple and easy to perform, as the medication is injected through a subcutaneous puncture using the accompanying injection device. Why is the Intrathecal Drug Infusion System effective in managing intractable pain? The spinal cord is the necessary route for any pain to be transmitted to the brain. Intrathecal drug infusion therapy directly injects drugs into the subarachnoid space, which acts on the corresponding sites in the spinal cord and produces a powerful central analgesic effect, thus greatly reducing the dosage of drugs. Taking morphine as an example, if the patient takes 300mg of morphine orally every day, then only 1mg is needed in the intrathecal. As the drug dosage is greatly reduced, the side effects are correspondingly few and mild, and even if they appear, they will disappear soon after a short period of adaptation. At the same time, the whole system is completely implanted in the patient’s body, which does not affect the patient’s daily life and greatly improves the patient’s quality of life. What kind of intractable pain can be effectively controlled by the Intrathecal Drug Infusion System? The indications of intrathecal drug infusion therapy are as follows: 1. Intractable cancer pain: after drug or surgical treatment with poor results; after traditional pain treatment methods can not achieve good results; drug treatment in the process of the emergence of more serious, intolerable side effects, and other mixed pain patients. 2. Intractable pain after back surgery 3. osteoporosis pain 4. complex focal pain syndrome 5. Axial trunk pain 6. Others, such as arachnoiditis, postherpetic neuralgia, etc. What are the contraindications and adverse effects of intrathecal drug infusion system? Contraindications: ① abnormal coagulation function, ② systemic infection or puncture site infection, ③ patients who can not accept the technology, ④ puncture and catheter retention pathway tumor invasion. Adverse reactions: ① bleeding, ② infection ③ cerebrospinal fluid leakage ④ catheter displacement, dislodgement, fracture and malfunction of infusion components ⑤ respiratory depression ⑥ constipation ⑦ nausea and vomiting ⑧ urinary retention ⑨ itching ⑩ allergy.