Knowledge sharing on needle topics

Release time：

2022-07-28 11:14

Speaking of needles, what will come to mind?
Probably "sewing needle", "guide needle", "retaining needle", "fish hook" and "injection needle"?
Today, let's talk about the "injection needle" that most people hate.

■ Injection
Injection is a method of drug administration, which refers to the injection of liquid medicine into the body with acupuncture.
Injection can be divided into intramuscular injection, subcutaneous injection, intradermal injection, intravenous injection and joint injection.
The name of the injection varies with the location of the injection, and also varies according to the time when the injection site is absorbed in the body.
In case of intramuscular injection, subcutaneous injection and intradermal injection, the injected liquid will diffuse into various tissues and then move to capillaries, and then move from capillaries to veins. Intravenous injection directly injects the solution into the blood vessel. Therefore, the fastest way to respond to the drug is intravenous injection. Next, they are intramuscular injection, subcutaneous injection and intradermal injection. Joint injection is also a direct injection to the problem site, so it is also an injection method with fast drug effect response.

■ Puncture
Puncture refers to inserting the needle into the muscles, joint cavity, abdominal cavity, chest cavity, bone marrow and other parts.
Puncture is used for treatment, examination or relief of symptoms.
Puncture used in the treatment process means not only to inject liquid medicine, but also to decompress brain pressure, discharge joint fluid and discharge pus. Puncture for examination refers to the extraction of blood, joint fluid, medullary fluid and leakage fluid for examination. Puncture for symptom relief means that when a large amount of ascites, pleural effusion, joint fluid and medullary fluid remain in the body, these fluids are discharged from the body through puncture.

■ Types of injection needle and puncture needle
The injection needle is mainly used for subcutaneous, muscular and intravenous injection.
Blood collection needle is mainly used for blood collection.
There are many cases of using injection needles.
Usually, blood is taken from peripheral veins.
There is also a micro blood sampling method, which refers to the use of special fine needles into the fingertips or earlobes for blood sampling to check blood sugar or blood routine.
The infusion device (drip dispenser) is composed of a ventilation needle, a bottle inserting needle, a drip pot, a flow regulator, a hose, etc.
The blood transfusion device is composed of a needle, a hose, a drip pot, a flow regulator and a filter used in blood transfusion.
The needle with wing is a needle with wing on the needle, which is used for drip and intravenous injection.
The indwelling needle for peripheral blood vessels refers to the needle used for continuous intravenous drip and long time infusion.
The utility model adopts a double-layer structure of an inner tube and an outer tube. The inner tube is a needle and the outer tube is a catheter.
The retaining needle for hemodialysis refers to the vascular retaining needle used in hemodialysis.

■ Size of injection needle
The thickness of the injection needle is expressed in "Gauge (G)".
For example, 18G indicates that the outer diameter is 1.250mm, 22G indicates that the outer diameter is 0.714mm, and 26G indicates that the outer diameter is 0.455mm. That is, the larger the G value, the thinner the injection needle.
The thickness of the injection needle mainly used by medical institutions ranges from 16G (outer diameter 1.6mm) to 27G (outer diameter 0.4mm). The needle for blood collection and inspection is about 21G~22GD, the injection needle for blood transfusion is about 18~20G, and the injection needle for muscle injection is about 21G~23G. Use about 26G fine needles for subcutaneous injection such as influenza vaccination.
The thickness of anesthesia needles used by dentists is mainly about 27G~33G. Recently, 31G~33G insulin injection needles have been used. In order to avoid using the wrong injection needle, medical institutions use color to distinguish the resin part of the needle (hub) or the outer package according to international standards. 18G is pink, 20G is yellow, 22G is black, and the color is roughly distributed in this way.

■ Needle tip of injection needle
There are two kinds of needle angles.
RB is the abbreviation of Regular Bevel. The needle angle is about 12 degrees. Subcutaneous injection and intramuscular injection use RB needle with less pain and easy puncture.
SB is short for Short Bevel. The needle angle is about 18 degrees. Arterial puncture and puncture use SB needle with obtuse angle and less risk of penetrating blood vessels.
In addition to the angle, the shape of the needle tip also has a variety of shapes, which are convenient for puncture and easy to stand upright into the body after puncture.
■ Length of injection needle
In addition to the thickness and needle angle of the injection needle, there is also the length of the needle.
The length of the needle is expressed in inches. One inch is 25.4mm. The 18G injection needle used for mixing medicine into the drip bottle and other occasions is generally 11/2 inches (38mm) long. The 22G injection needle used for blood collection is generally 11/4 inch (32mm) to 11/2 inch (38mm) in length, but its length is different due to different parts or manufacturers.