2.5. Interventions
To ensure the reliability and authenticity of the experiments and reduce the bias caused by external factors, centralized training is conducted for the general nurses in the intensive care unit who participate in the research to achieve the purpose of homogenization.Selection of locking fluid and locking method: The selected subjects are all indwelled double-lumen catheters with single-use CVCs kit TYPE I (Henan Tuoren Medical Instrument Group Co., LTD.); specifications: 2-7FR-20cm, outer diameter of catheter 2.4 mm, length of catheter 20 cm. All catheters are inserted under ultrasound guidance and standard hygiene precautions are taken to minimize contamination.Experimental group: Taking 5 mL from a dose of 200 mL of 4% sodium citrate (Chengdu Qingshan Likang Pharmaceutical Co., LTD., Production batch NO. A2101013) as tube locking liquid.Control group: Taking 0.4 mL from a dose of 12500 u/2mL Heparin sodium injection (Chengdu Haitong Pharmaceutical Co., LTD., Approval no. H51021209) and adding 250 mL 0.9% sodium chloride injection as a mixture. After uniform preparation, a 5 mL mixture is taken as the tube locking liquid. The concentration of heparin in tube locking fluid is 10 U/mL.Flushing CVCs must be performed using turbulence with 10 mL 0.9% sodium chloride injection before and after each infusion, medication, parenteral nutrition, transfusion of blood products, and replacement of pipeline equipment. Sodium citrate tube locking solution is used in the experimental group, heparin tube locking solution is used in the control group and a positive-pressure locking technique is used to lock the tube. CVCs that are not currently in use are flushed and locked once a day [