I. The role of intravenous access in critical care emergency
(A) the concept of critical illness
Acute patients refer to the state that the patient’s life is threatened by sudden illness and trauma, such as traumatic hemorrhagic shock, thoracic and abdominal hemorrhage, heart or large blood vessel rupture and bleeding, cardiac arrest caused by various reasons, poisoning, etc.
Severely ill patients refer to patients with extreme depletion and disturbance of the internal environment caused by various etiologies, such as diabetic hyperosmolar coma ketoacidosis, advanced cancer cachexia with sudden cardiac arrest, etc. This state requires the emergency medical staff to establish good venous access for the patient in a very short time to start the treatment.
(B) the role of intravenous access in the clinical work
1. Liquid therapy, replenish the patient’s missing and daily need of water, restore and maintain the circulating blood volume, replenish various electrolytes, adjust acid-base balance.
2. Administering a large number and variety of antibiotics through intravenous access.
3. Replenish nutrients, including various preparations of sugar, fat and amino acids.
4. Various stimulating drugs and fluids such as anti-tumor drugs.
5. Vasoactive drugs that can work quickly, etc.
Second, the type of intravenous access: 8 parts 16 points
Venous access can be divided into two categories: peripheral venous access and central venous access. The summary of the sites available for establishing venous access is 8 sites and 16 points. Including the trunk and branches of cephalic vein, noble vein and saphenous vein, internal jugular vein, external jugular vein, superior and inferior access of subclavian vein and femoral vein.
1.Comparison of veins at each site
To evaluate which venous access is more reasonable for patients, we can consider the speed of fluid administration, the type of drug used, the tolerance of blood vessels to drug irritation, the circulation time required from the site of drug intake to the site of effect, whether blood specimens can be taken, and whether cardiopulmonary function can be monitored.
2.The advantages of central venous access.
Simple, fast, practical and reliable access.
Can monitor central venous pressure to guide fluid therapy.
Can monitor the central venous blood gas and oxygen metabolic rate.
Central venous drug delivery has a positive impact on the effect of cardiopulmonary resuscitation.
Represent the level of critical care resuscitation and treatment.
Third, the general principles of establishing venous access
In the resuscitation and treatment of critically ill patients, it is necessary to establish 3~5 venous accesses and 1 arterial access. The following ideas are recommended for reference, one or more of which may be used, selected, or combined.
The first one: rapid rehydration and/or monitoring of central venous pressure.
Number 2: Rapid replenishment of various colloid fluids.
Number 3: Replenish fluids with high viscosity.
Number four: administration of vasoactive drugs.
One arterial access: perform invasive blood pressure monitoring and draw blood gas or other blood specimens.
In hospitals where puncture placement is available, phlebectomy should not be the first choice.
Fourth, the characteristics of various venous access, the use of
(A) Peripheral venous access
Location: main trunk of cephalic vein, noble vein, saphenous vein and its branches.
Advantages: rapid, safe, easy to operate, not high technical requirements, multiple vessels can complete multiple treatments at the same time, the use of cannula needle can achieve more rapid rehydration.
Disadvantage: central venous pressure monitoring cannot be done.
(B) Central venous access
Internal jugular vein access
①Site: the needle is inserted at the apex of the arterial triangle enclosed by the clavicle as the base, the medial head of the sternocleidomastoid muscle as the medial side, and the lateral head of the sternocleidomastoid muscle as the lateral side.
②Method: Pillow under the shoulder, try to puncture with the skin at an angle of 30~50 degrees toward the ipsilateral anterior superior iliac spine or the nipple, and generally enter the needle about 4cm. ③Role: infusion, pressure measurement, cardiac catheter.
(iii) External jugular vein access
(①Site: descending vertically behind the angle of the mandible, with clear body surface and clear positioning.
(ii) Method: Head is turned to the opposite side and punctured along the vessel at an angle of about 45 degrees to the skin.
(iii) Role: Infusion and pressure measurement. (iii), subclavian vein superior approach ⒈ site: the vessel is located in the posterior inferior clavicle, is a continuation of the axillary vein, superficial and coarse.
Methods.
①Intraclavicular 1/3 point puncture method: the upper edge of the clavicle, at the junction of the internal and middle 1/3 of the clavicle, 3 cm after the clavicle, at 45 degrees to the sagittal plane, and 3~5 cm into the needle in the frontal plane, can be punctured into the subclavian vein.
② Posterior margin of sternocleidomastoid muscle puncture method: at the upper edge of the clavicle, 1~2cm after the outer edge of the lateral head of the sternocleidomastoid muscle, the direction of the needle is 45 degrees to the midline, and 3~4cm towards the front of the body, towards the center of the sternal angle, the subclavian vein can be penetrated.
Effects.
Infusion, nutrition, stimulating fluid, pressure measurement, widely used.
(D) Subclavian vein inferior approach
1.Methods: inner third of the clavicle intersection access method, outer third of the clavicle intersection access method, clavicle midpoint approach method, He Zhongjie three midpoint method, etc.
1.Contraindications: local deformity, infection, trauma, emphysema, coagulation disorder, etc.
(E) Femoral vein access
1.Site: 3~4cm below the inguinal ligament in the femoral triangle, 1.0cm inside the femoral artery pulsation.
2.Method: 20~45 degrees from the horizontal plane, along the direction of the femoral vein, and 3~5cm into the femoral vein.
3.Deficiency: long time indwelling catheter is prone to infection.
4.Note: The position of penetration into the femoral vein should not be higher than the inguinal ligament to avoid intra-abdominal and retroperitoneal bleeding, which is difficult to control.
Note: In clinical practice, we should master multiple puncture methods of multiple veins, “which vessels are suitable for patients, I will do which ones”; avoid the wrong idea of “which vessels I can do puncture, I will do which ones”.
V. Management after the establishment of venous access
After the establishment of venous access, careful management should be carried out to prevent and reduce the occurrence of complications. Properly fix the catheter to prevent dislodgement and bleeding; do a good job of local protection to prevent needle infection; use the catheter correctly to prevent fungal infection in the catheter; prevent coagulation in the catheter; prevent obstruction, embolism and thrombosis after vascular puncture.