Method for judging whether catheter tip is located in superior vena cava during operation

Abstract

The invention provides a method for judging whether a catheter tip is located in a superior vena cava by observing whether a gas-liquid plane in a catheter extension tube fluctuates regularly or not in an operation. When the non-valve type central venous catheter is placed in an operation, a stable and observable gas-liquid plane is formed in the catheter extension tube after the catheter is conveyed to an expected length. When the patient is in a resting state and the gas-liquid plane is observed to have regular fluctuation consistent with the heart rhythm, the tip of the catheter is judged to be located in the superior vena cava during the operation; if the gas-liquid plane does not fluctuate, judging that the tip of the catheter is not in the superior vena cava during the operation. The method is simple and easy to operate, does not need to add any instrument and equipment, and is high in sensitivity and specificity.

Description

Technical Field

[0001] The present application relates to a method for determining whether the tip of a catheter is located in the superior vena cava during non-valvular central venous catheter insertion. Background Art

[0002] The location of the catheter tip in the superior vena cava is a sign of successful central venous catheterization. The superior vena cava has a large blood flow and a fast blood flow rate, and the drugs infused through the central venous catheter are quickly diluted to avoid drug damage to the blood vessels. If the catheter tip is located outside the superior vena cava, it is defined as catheter malposition. In this case, it is not recommended to retain or use the catheter. If used, complications such as catheter blockage, phlebitis, and venous thrombosis are likely to occur.

[0003] Currently, chest X-ray examination is the gold standard for confirming that the catheter tip is located in the superior vena cava. Usually, chest X-ray examination is performed after catheterization. If the chest X-ray examination finds that the catheter is malpositioned, the position of the catheter tip needs to be adjusted to the superior vena cava under sterile conditions, or the puncture site needs to be reselected to insert the catheter. After the catheterization, chest X-ray examination is still required to confirm that the catheter tip is located in the superior vena cava. This not only wastes time, but also increases catheter-related costs and patient anxiety. Therefore, it is particularly important and urgent to find a method to determine that the catheter tip is located in the superior vena cava during catheterization.

[0004] At present, intracavitary electrocardiogram (IC-ECG) is the most commonly recommended method for determining whether the catheter tip is located in the superior vena cava during central venous catheterization. IC-ECG can determine whether the catheter tip is located in the superior vena cava during surgery by analyzing and observing specific P waves. This method requires the installation of electrocardiogram electrodes before catheterization, and a special guide wire is inserted during surgery, and the other end needs to be connected to the electrocardiogram. This method is cumbersome to operate, difficult to identify, time-consuming and labor-intensive, and increases the risk of postoperative infection. Because this method requires special equipment, it has not yet been popularized. Summary of the invention

[0005] During a large number of catheterization operations, we observed a physiological phenomenon: in the existing catheterization technology, after the non-valvular central venous catheter is delivered to the expected length, when the patient is in a resting state, the gas-liquid level in most catheter extension tubes fluctuates regularly, and the rhythm of this fluctuation is consistent with the heart rhythm. A 1967 paper [Reference 1] also recorded this physiological phenomenon, which is completely consistent with the physiological phenomenon we observed.

[0006] We observed that for those catheters with regular fluctuations, the catheter tip was confirmed to be in the superior vena cava during postoperative chest X-ray examination, while for catheters without fluctuations, the catheter tip was not confirmed to be in the superior vena cava during postoperative chest X-ray examination. Based on the causal relationship between the presence or absence of regular fluctuations and the location of the catheter tip in the superior vena cava, we applied for a method to determine whether the catheter tip is in the superior vena cava during surgery. This method is simple and easy to operate, does not require the use of any instruments, and has high sensitivity and specificity.

[0007] The method is specifically described as follows: during the non-valve central venous catheter insertion operation, after the catheter is delivered to the expected length, when the patient is in a resting state, if it is observed that the air-liquid level in the catheter extension tube fluctuates regularly in accordance with the heart rhythm, then it is judged during the operation that the catheter tip is located in the superior vena cava; if there is no fluctuation in the air-liquid level in the catheter extension tube, then it is judged during the operation that the catheter tip is not in the superior vena cava.

[0008] In the existing catheterization operation process (Sedinger technique), when the catheter is delivered to the expected length, the syringe is connected to the catheter extension tube, and blood is drawn back to prove that the catheter is in the venous cavity. The syringe is removed and the liquid level in the extension tube is allowed to naturally drop to the middle section of the extension tube and the syringe is connected again. At this time, a stable and observable air-liquid level is formed in the extension tube. When the patient is in a resting state, the air-liquid level in the catheter extension tube is observed for regular fluctuations.

[0009] The air-liquid level in the catheter extension tube fluctuates regularly. The fluctuation rhythm is consistent with the heart rhythm, the fluctuation rhythm is about 1-2 times / second, and the fluctuation amplitude is about 5 mm. When the air-liquid level fluctuation in the catheter extension tube is not observed with the naked eye, it is considered to be no fluctuation.

[0010] If the air-liquid level in the catheter extension tube is observed to fluctuate regularly in accordance with the heart rhythm, it is judged during the operation that the catheter tip is located in the superior vena cava.

[0011] If there is no fluctuation in the air-liquid level in the catheter extension tube, it is judged that the catheter tip is not in the superior vena cava. At this time, it is considered that the catheter tip is dislocated, and the position of the catheter tip needs to be adjusted during the operation and the position of the catheter tip needs to be judged again.

[0012] A chest X-ray is performed after all catheterization procedures.

[0013] The method described in the present application adds an operation procedure of establishing an air-liquid level in the catheter extension tube during the catheterization process, and observing whether the air-liquid level fluctuates when the patient is in a resting state. The method is simple and easy to operate, and does not require the addition of any instruments or equipment. DETAILED DESCRIPTION

[0014] In the existing catheterization operation process (Sedinger technique), when the catheter is delivered to the expected length, blood is drawn back, the syringe is removed, and the liquid in the catheter extension tube is allowed to naturally drop to the middle section of the extension tube, and then the syringe is connected again. At this time, a stable and observable air-liquid plane is formed in the middle section of the catheter extension tube.

[0015] Ask the patient to be in a resting state and observe whether there are regular fluctuations in the air-liquid level in the catheter extension tube. It is easier to observe when the catheter contains light blood-containing liquid.

[0016] The method of observing whether there is any fluctuation in the air-liquid level in the catheter extension tube refers to the fluctuation of the air-liquid level visible to the naked eye of the observer. The presence or absence of fluctuation has nothing to do with the amplitude of the fluctuation. It only takes 5-10 seconds of observation.

[0017] illustrate The main purpose of this application is to determine whether the catheter tip is located in the superior vena cava during non-valvular central venous catheter insertion. If the catheter tip is not located in the superior vena cava during the operation, the position of the catheter tip is adjusted immediately, which is beneficial for technicians in this field to reduce the incidence of catheterization complications and improve the success rate of catheterization. The scope of protection of this application can be publicly promoted and applied.

[0018] References 1: Mogil RA, DeLaurentis DA, Rosemond GP. The infraclavicular venipuncture. Value in various clinical situations including central venouspressure monitoring. Arch Surg. 1967 Aug;95(2):320-4.

Claims

1. During the operation, observe whether the air-liquid level in the catheter extension tube fluctuates regularly to determine whether the catheter tip is located in the superior vena cava, which includes: During non-valvular central venous catheter insertion, when the catheter is delivered to the expected length; Connect the syringe to the catheter extension tube, draw blood back to prove that the catheter is in the venous cavity, remove the syringe and let the liquid level in the extension tube naturally drop to the middle of the extension tube, then connect the syringe again, and a stable and observable gas-liquid level will be formed in the extension tube; When the patient is at rest, regular fluctuations of the air-fluid level consistent with the heart rhythm are observed, and the catheter tip is judged to be in the superior vena cava during the operation; When the patient is at rest, no fluctuation in the air-fluid level is observed, which indicates that the catheter tip is not in the superior vena cava during surgery.

2. A method for determining that the tip of the catheter is located in the superior vena cava by observing regular fluctuations in the air-liquid level during surgery, characterized in that: When the patient is at rest; It was observed that the gas-liquid level fluctuated regularly, with a rhythm consistent with the heart rhythm, about 1-2 times per second, and an amplitude of about 5 mm.

3. A method for judging that the catheter tip is not in the superior vena cava by observing that there is no fluctuation in the air-liquid level during the operation, characterized in that: When the patient is at rest; No fluctuations in the gas-liquid level were observed with the naked eye.

4. The non-valvular central venous catheters involved in this method include: Central venous catheter (CVC catheter); Non-valvular infusion port (PORT); Non-valvular PICC; Central venous catheter for dialysis; Other non-valvular central venous catheters.

5. The method described in this method forms a stable and observable gas-liquid level in the catheter extension tube: During non-valvular central venous catheter insertion, when the catheter is delivered to the expected length; Connect the syringe to the catheter extension tube, draw blood back to prove that the catheter is in the venous cavity, remove the syringe and let the liquid level in the extension tube naturally drop to the middle of the catheter extension tube, then connect the syringe again. At this time, a stable and observable gas-liquid level is formed in the catheter extension tube; Currently, the commonly used infusion port catheter kits are not equipped with catheter extension tubes. You can first use the CVC catheter for puncture, and then replace the infusion port catheter after confirming that the catheter tip is in the superior vena cava during the operation.

6. This method describes a central venous access catheter with the tip located in the superior or inferior vena cava. Common puncture sites include: Upper arm veins (basilic vein, brachiocephalic vein, brachial vein, axillary vein, etc.); Internal jugular vein; Subclavian vein; Femoral vein; Other veins.

7. A method for determining whether the tip of a catheter is located in the superior vena cava during catheterization: an operation procedure of establishing an air-liquid plane and observing whether the air-liquid plane fluctuates is added during the catheterization process. The method is simple and easy to operate, does not require any additional instruments, and has high sensitivity and specificity.