Intubation through elbow vein or femoral vein is far away from the heart, especially when the catheter is reused, it may be difficult to operate because it is soaked in the blood flow in the body for a relatively long time, and the catheter becomes soft and easy to bend, which leads to intubation failure. If the catheter is used for intraoperative monitoring of some patients before major surgery, because of the anatomical position of the catheter here, the operator and the monitor may influence each other during the operation; For example, the probability of contamination of femoral vein catheterization itself and postoperative catheter maintenance are relatively increased. In view of these unfavorable factors, clinicians rarely choose distal vein intubation, but prefer to put tubes in internal jugular vein or subclavian vein. Insertion of catheter through this vein into the blood passage is relatively smooth, and the insertion length is almost half of that of distal vein catheterization, so the pollution opportunity is small, which is convenient for clinical monitoring and nursing. However, the operator is required to be comprehensive in technology and clear in anatomical position in order to avoid some complications as much as possible. Of course, people who are intubated for the first time are most sure of themselves, and the venous blood path chosen is the best, because the intubation may be 1 time.
The average distance from elbow vein or femoral vein to pulmonary artery is 55 ~ 65 cm, and the average distance between internal jugular vein and subclavian vein is 35.45cm. Environmental preparation: the operation should be carried out in a clean and ventilated cardiac catheterization operating room or ward. The ground is disinfected with 2 ~ 5% Lysol, and the operating bed and unit can be irradiated with ultraviolet rays for 30 minutes.
Setting of cardiac catheterization room: The cardiac catheterization room can be set up independently in ICU, which is a single room of 16 ~ 20m2. The room is equipped with an operating bed, and there are X-ray machines, ECG monitors, RJ45 net ports, defibrillators, anesthesia machines and tracheal intubation items beside the bed. Oxygen and negative pressure gas source, sphygmomanometer, stethoscope, etc. It is also an indoor necessity. In addition, the cardiac catheterization room should also store sterile intubation instruments and rescue drugs for use.
2. Preparation of articles: aseptic Swan-Ganz balloon floating catheter 1 root. Venous puncture needle, guide wire, dilator, surgical blade, tee plate, etc. Soak in alcohol for later use.
Twisted pair network cable, bedside monitor.
Iodine, alcohol, gentian violet, cotton swab and 5ml empty needle for standby.
Catheter packaging:
2 surgical gowns; 6 sterile towels;
Rectangular therapeutic plate1; 4 pieces of sterile gauze;
4 mosquito forceps; 1 mosquito clamp;
Toothed pliers handle; 1 handle;
Koko pliers1; Alice forceps1;
Leather sewing needles and threads; Sterile gloves 2 pairs;
2 therapeutic bowls; 4 towel tongs;
4 yarn balls; 5ml and 20ml syringes;
No.7 long needle 1.
Note: the contents of the catheter bag are complete, and the double-layer foreskin is wrapped and sterilized by high pressure for later use.
3. Pharmaceutical preparations: lidocaine, propranolol, nitroglycerin, epinephrine, atropine, diazepam, flumethasone, curare, dopa gum, etc.
2% procaine
Heparin solution configuration: heparin 100mg/ branch is added to 0. 9% saline 1000ml, equivalent to 12.5 IU/ml. Among them, 500ml is a bottle connected to an intravenous infusion tube, which is used after being exhausted.
4. Patient preparation: supine position, head tilted to one side, and intubation site clean.
Recording vital signs: Connect the monitor with twisted-pair network cable, and record blood pressure, heart rate, respiratory rate, consciousness state, etc. On the nursing record sheet.
Height is in centimeters and weight is in kilograms.
Calculated body surface area: defined as the area occupied by each person in space, in m2. The relevant indicators are height and weight.
(l) Calculation formula: body surface area (m2) = 0.006× height (cm)+0.0 128× weight (kg)-0. 1529. Operators wear hats, masks, brush their hands and perform aseptic surgery.
Insertion of internal jugular vein catheter:
Anatomy of internal jugular vein: The internal jugular vein continues in the sigmoid sinus and passes through the skull base. It first descends outside the internal carotid artery, then descends outside the common carotid artery, and is enclosed in carotid sheath with the vagus nerve behind the artery and vein. The lower end of the internal jugular vein is enlarged and deep. Under the cover of sternocleidomastoid muscle, the cervical root meets the subclavian vein (Figure 20).
Operating steps: the patient lies on his back, turns his head to the left, keeps his head at a low position of 30 degrees, draws a triangle of the neck with gentian violet, and locates it at the midpoint of the top of the triangle.
There are two surgeons under the stage, 1 nurse.
Routine local skin disinfection, towel spreading and 2% procaine infiltration anesthesia.
In the synchronous stage, the intravenous puncture needle, dilator, guide wire, blade and tee plate (made up of three tees) soaked in alcohol are handed over. Sterile Swan-Ganz catheter. Place in the sterile area of the opened catheter package. Put proper amount of alcohol and heparin saline into two processing bowls.
The operator should check the cardiac catheter: the catheter should have a normal curvature, and if it is obviously dead, it should be discarded, otherwise it will be difficult to place the catheter. Use lml syringe to suck 0.8 ~ LML of air, and fill the air bag. Check whether the balloon of the catheter leaks or the balloon is biased to one side. If the airbag ruptures or leaks slowly, the catheter should be replaced. Attention should be paid to the fact that the airbag is biased to one side, which may affect the accuracy of the monitoring value.
After checking the available cardiac catheters, pump heparin saline into each lumen with a 20ml syringe, and connect with the tee plate to exhaust the gas in the catheter and tee for later use.
Check whether the puncture needle, dilator and guide wire can be used together, and wash them with heparin saline for later use.
Puncture method: the index finger and middle finger of the operator's left hand touch the surface of carotid artery and push it inward to keep it away from the anterior edge of sternocleidomastoid muscle. At the midpoint of its leading edge, the needle is inserted at an angle of 30 ~ 45 degrees with the frontal plane, and the needle points to the ipsilateral nipple on the tail side. After the puncture needle entered the skin to extract venous blood, it was proved that the puncture was successful. Put in the guide wire and pull out the puncture needle. The puncture hole was slightly expanded with a blade, and the outer cannula was placed in the internal jugular vein with a dilator guided by a steel wire. Pull out the guide wire and dilator, and then insert the cardiac catheter through the outer sleeve, so that the catheter can quickly enter the cardiac cavity in a short distance.
Turn on the X-ray machine and track the insertion position of the heddle catheter until it enters the pulmonary artery. When the balloon inflates, the catheter enters the distal end of the pulmonary artery. After the balloon was deflated, the catheter quickly returned to the original pulmonary artery position, which proved that the position was good. After external fixation.
In practical work, some patients can't move to the catheter room because of their critical condition, or there is no X-ray machine equipment in the ward. It is feasible to blindly insert Swan-Ganz catheter at the bedside, and often the catheter can be successfully placed.
The so-called bedside blind catheterization is to judge the position of catheter indirectly through the pressure waveform in a heart, which requires certain basic knowledge and clinical experience.
When bedside blind intubation, the tee plate at the end of the cardiac catheter should be connected to the sensor, so that the pressure waveform of each cardiac cavity can be directly displayed on the bedside monitor, and synchronous ECG monitoring is needed.
The implanted cardiac catheter first enters the right atrium through the superior vena cava or inferior vena cava, and the pressure waveform in the right atrium appears on the monitor, and then enters the right ventricle through the tricuspid valve through blood flow guidance, and the catheter balloon inflates and floats on it. Through the pulmonary valve to the pulmonary artery and finally into the distal branch of the pulmonary artery for embedding. After the deflated balloon is deflated, the catheter quickly retreats to the pulmonary artery. After confirming that the catheter is in good position, sew a needle outside the skin to fix the catheter, and cover the puncture point with sterile dressing and fix it with adhesive tape.
In short, the floating catheter enters the pulmonary artery by the thrust of blood flow on the catheter balloon. Because of the geometric relationship between the balloon surface and the blood flow force, the floating catheter can obtain the maximum floating force with a small balloon area and is easy to drift into the pulmonary artery. And because the inflated balloon makes the catheter tip not exceed the balloon surface, the original force applied to the catheter tip is dispersed on the inflated balloon surface, thus reducing the stimulation to the endocardium. Therefore, Swan-Ganz catheter has three advantages: less ventricular arrhythmia, rapid implantation in pulmonary artery and no need of X-ray fluoroscopy, and has become a standard bedside method for measuring hemodynamic parameters.
In addition, subclavian vein is often chosen as the blood flow channel for inserting Swan-Ganz tube. The similarities and differences between subclavian vein and internal jugular vein intubation are that the patient takes the supine head and then takes the low position. Because of its different anatomical positions, the puncture needle can directly puncture the vein through the clavicle, and then operate it in turn until the cardiac catheter is sent to the heart. Its disadvantage is that there are many complications, which are directly related to the operator's surgical proficiency. For the first intubation, a balloon floating catheter can also be inserted through elbow phlebotomy, but if the catheter is kept for a long time, it will easily cause superficial phlebitis and is generally not used as a catheter access. 1. Arrhythmia: It is a common complication of intubation. Because the tip of the catheter touches the myocardial wall or heart valve, it can prevent ECG changes such as ventricular premature beats and supraventricular tachycardia. Ventricular premature beats will disappear soon after catheter removal. However, if serious arrhythmia occurs, such as ventricular tachycardia and ventricular fibrillation, the cardiac catheter should be removed immediately, and medical treatment and first aid should be given.
Note: ECG must be continuously monitored during the operation, and the inserted catheter cannot be forced to enter when it encounters resistance. Patients with myocardial insufficiency or heart disease can be given nitroglycerin 5mg per day before operation and given oxygen inhalation treatment. Lidocaine 50mg was injected into patients with original arrhythmia to prevent recurrence. The patient's bedside must have first-aid medicine.
2. Catheter balloon rupture; It is common to use catheter repeatedly, resulting in the loss of balloon elasticity. The index of pulmonary artery buried pressure is lost after airbag rupture, which may lead to air embolism due to airbag reinflation.
Note: The maximum inflation volume of the airbag shall not exceed1.5ml. Air, carbon dioxide gas or physiological saline can be used to inflate the airbag clinically. However, the latter two are inconvenient to operate and difficult to deflate, so they are rarely used. If the balloon is found to be broken, it is not necessary to remove the cardiac catheter for the time being. The end of the catheter should be marked and shifted to prevent others from doing the balloon inflation test again (especially when the catheter position seems to change).
3. Infection and thrombophlebitis: Due to lax aseptic operation during catheter placement, incomplete disinfection of repeatedly used catheters, and pollution during catheter maintenance, blood pollution can be directly caused, and patients may have high fever, chills and even sepsis in clinic. Thrombophlebitis mostly occurs in patients with peripheral venous catheterization. It is closely related to the retention time, and the longer the time, the higher the incidence.
Note: The aseptic requirements of intraoperative and postoperative operations must be emphasized, and the used catheters should be handled very strictly, and sterilized items should be cultivated regularly. The wound of skin intubation should be changed/kloc-0 times a day, and the local area should be kept clean and dry. The best indwelling time of cardiac catheter should not exceed 72 hours to prevent infection and thrombophlebitis.
4. Pulmonary embolism: the balloon inflated at the tip of the catheter is embedded in the pulmonary artery for a long time or the catheter moves in the pulmonary artery many times during intubation.
Note: In addition to mastering some skilled operation skills and paying attention to the time of catheter balloon inflation, continuous balloon inflation is generally not advocated, but the average pulmonary artery pressure is used as a clinical continuous monitoring index to indirectly reflect the changes of pulmonary artery entrapment pressure.
5. Catheter blockage or pulmonary artery thrombosis: It is more common in patients with a history of embolism and hypercoagulability. Preventive anticoagulation therapy should be taken, all chambers of cardiac catheter should be flushed with heparin saline 65438 0 times per hour, and the changes of intracardiac pressure diagram should be paid attention to to to keep the cardiac catheter unobstructed.
6. Pulmonary artery rupture: seen in patients with pulmonary hypertension and vascular wall degeneration, caused by repeated movement of catheter in pulmonary artery and excessive inflation of balloon. Attention should be paid to maintaining proper balloon inflation and closely monitoring the changes of pulmonary artery pressure.
7. The catheter is twisted and knotted in the heart cavity: it occurs when the catheter is soft and easy to bend and the inserted blood vessel is too long. Pay attention to the length of catheter insertion, which should not exceed 15 cm from the right atrium to the pulmonary artery. If distortion is found, it should be withdrawn. If the knot has been knotted, the needle wire can be inserted into the catheter to untie the knot and exit. If it doesn't work, we have to tie the knot and pull it out slowly. The floating catheter inserted into the heart cavity is of great value for evaluating the dynamic state of circulation. However, due to the long catheter, each lumen is very narrow, which is easy to cause embolism in the catheter. In order to ensure the maximum effective use of catheter, it is necessary to set up heparin solution flushing device.
Heparin solution: dilute 6250IU heparin into 500 ml of 0.9% physiological saline, so that each ml of liquid contains 12.5IU heparin.
Indications for catheter irrigation:
1. Abnormal cardiac pressure image: the monitored pressure wave flattens, and the pressure value is obviously different from before.
Another abnormal waveform phenomenon is caused by the change of catheter position. If the catheter exits the pulmonary artery, the right ventricular pressure image will be displayed on the monitor, which is not caused by lumen obstruction, and the irrigation is invalid. Catheter should be reset under aseptic operation or confirmed by X-ray chest film.
2. Before each measurement of a complete set of hemodynamic indexes, in order to ensure the accuracy of the numerical value, each lumen should be flushed 65438 0 times.
3. Routine maintenance catheter heparin solution flushing is 65438 0 times per hour. Methods: The same arterial perfusion method was used.
Note: the external flushing device of floating catheter is the easiest to be polluted, especially the syringe used to flush the lumen for many times. Because the needle plug is frequently exposed to the air, the hands of medical staff operate directly, and the chances of pollution are the most. In order to prevent the occurrence of blood-borne infection, syringes should be replaced every day, strictly speaking, after each use.
The indirect flushing device is unreasonable, and in view of China's economic situation, disposable syringes can not be widely used, so we should try our best to reduce the pollution of syringes and extend their service time.
Method introduction: Pull open the pin. Put sterile plastic bags from the tail to the front and wrap them around the syringe with adhesive tape, which will not affect the pumping out of heparin solution. Replace the syringe every 8 ~ 12h.
In the flushing operation, it is very common that the nipple end of the glass syringe is broken in the tee due to excessive hand force or angle deviation, which brings trouble to the nursing work and damages the tee and the syringe. This makes the choice of its empty meter biased towards plastic products as far as possible, and this syringe completely avoids the above injuries.
The irrigation and pressure measuring devices outside the catheter should be closely connected, otherwise it is easy to cause blood return in the lumen and cause blockage.
Clinically, if the patient has high fever, chills and other manifestations, and highly suspects that the cardiac catheter is polluted, the catheter should be removed immediately, and the residual blood in the catheter should be cultured and treated with antibiotics.
Generally, the indwelling time of floating catheter is 3 ~ 5 days, and it can be kept for 9 days or more. However, the reliability of catheter pressure value after indwelling for more than 5 days is generally doubted. If thrombophlebitis or embolism occurs, the catheter should be removed. The best time for indwelling catheter is 48 ~ 72h. The direct indexes obtained from Swan-Ganz balloon floating catheter are right atrial pressure (RAP), pulmonary artery pressure (PAP), pulmonary artery entrapment pressure (PCWP) and cardiac output (CO). Indirect indexes calculated by the formula include pulmonary circulation resistance (PVR), systemic circulation resistance (SVR), stroke work (SW), left ventricular stroke work (LVSW), right ventricular stroke work (RVSW) and cardiac index (CI). If necessary, a mixed venous blood sample can be collected through a catheter to determine the venous oxygen partial pressure (PvO). ), indirectly understand the ventilation function.
Method:
Pressure measuring device and catheter flushing device:
1. Adjust the zero point: make the sensor at the same level as the patient's heart, and twist the tee to make the sensor communicate with the atmosphere. When the pressure value of the monitor shows zero, it means that the zero adjustment is completed.
2. Flush each lumen to make the sensor communicate with one lumen.
3. Prepare the cardiac output monitor, adjust it to the ready working state, and input the patient's blood temperature and the temperature of the externally controlled ice water. Suck 10ml sterile iced saline repeatedly with 10ml syringe and connect it to the end of the catheter leading to the right atrial cavity.
Push the ice salt water in 4.4 seconds and press the cardiac output monitor at the same time, and the machine will display the cardiac output value.
5. Record PAP, PCWP, BP, HR and RAP synchronously.
PAP: It is measured by communicating the sensor with the lumen leading to pulmonary artery.
PCWP: On this basis, the catheter balloon is inflated and the catheter floats into the pulmonary capillaries.
RAP: It is measured by connecting the sensor with the cavity leading to the right atrium.
Blood pressure and heart rate: measured by conventional methods.
Present, Past and Future of Floating Ducts
The floating catheter was put into use on 1970, which can be completed even if the critically ill patient is at the bedside for a few minutes. Although it is not difficult to place these catheters, some training and experience are necessary in order to obtain reliable hemodynamic data through pulmonary artery intubation and reduce the occurrence of complications. Because balloon floating catheter has many advantages compared with traditional catheter, it is used in patients without indications and overused in intensive care unit, which leads to many complications and increases mortality.
Prospective randomized controlled studies report that in most clinical cases, the routine use of floating catheters has no indication. These results are not surprising, because floating catheter is a diagnostic method rather than a treatment. We used floating catheter to monitor critically ill patients and obtained a lot of hemodynamic data. In addition, through direct detection of hemodynamics, we have gained a wealth of clinical knowledge and experience about hemodynamics.
It should also be recognized that despite the increase and improvement of non-invasive imaging methods, floating catheter is needed to detect hemodynamics in some clinical situations, but only experienced doctors can complete this operation. The correct use of floating catheter monitoring has greatly improved our understanding of hemodynamics. Its abuse, especially by relatively inexperienced operators, will lead to serious complications and even death.
Prospective randomized clinical trials show that routine use of floating catheters will not bring any benefits. However, floating catheters can still be used in many clinical situations.