Medical consumables trivia - talk about the different types of syringes
The syringe consists of a syringe barrel with a small hole at the front end and a matching piston core rod. Syringes are used to inject small amounts of liquid or gas into or out of areas that are not accessible by other methods. When the rod is pulled out, the liquid or gas is drawn through the small hole at the front of the syringe, and the liquid or gas is squeezed out when the rod is pushed in. The process of extracting or injecting gas or liquid with a syringe and needle is called injection.
1. Needle syringe
As an application of Pascal's law, Blaise Pascal invented the syringe around 1650. Charles Gabriel Pravaz and Alexander Wood are often cited as the ancestors of syringes for medical use, and in 1853 they developed a medical syringe with a thin needle that could penetrate the skin. However, the Iraqi and Egyptian surgeon Ammar ibn 'Ali al-Mawsili' had developed a similar syringe using a hollow glass tube in the 9th century AD to suck out cataracts in the patient's eye, a method that was still in use until at least 1930, and improved in the 20th century.
Syringes are often attached to hypodermic needles to inject liquid or gas into or out of body tissues. They can also be used in medical devices, containers, or scientific instruments such as some chromatography methods to inject through rubber diaphragms. Injecting gas into blood vessels will cause air embolism. The way to remove air from the syringe to avoid embolism is to turn the syringe upside down and squeeze out a little liquid before injecting into the bloodstream.
Syringes can be made of plastic or glass, and usually have a scale indication indicating the volume of liquid in the syringe. Glass syringes can be sterilized with autoclaves, but because plastic syringes are less expensive to handle, most modern medical syringes are made of plastic, which further reduces the risk of bloodborne diseases. Among drug users who inject intravenous drugs, the spread of the disease, especially HIV and hepatitis, is associated with the reuse of needles and syringes. At present, most of the syringes used for vaccination and blood drawing are made of plastic, which are only used for one-time use and discarded when they are used up to avoid cross-infection of infectious diseases caused by reusing syringes. In some cases where accuracy is not a priority for germs, such as quantitative chemical analysis, glass syringes are still used due to their small error and smooth actuator movement. The needle of the syringe is very small and fine.
2. Rectal and vaginal syringes
There is a spherical syringe for enemas, and rinses with a bulb attached to a nozzle in which the liquid is filled, and the nozzle extends into the rectum or vagina to squeeze the bulb to spray liquid. There is also a syringe with a reservoir where the liquid is stored in a bag or can flow through a tube to the nozzle. Enemas used to be used this way.
3. Jet syringe
A jet syringe is a type of syringe that uses high pressure to spray a fine beam of liquid to achieve the effect of injection. These syringes are actuated by an external air supply line, an external or built-in cylinder and a spring. Jet syringes are well suited for mass vaccination and repeated insulin injections for diabetics. Similar devices can be used industrially to inject grease or other liquids
4. Non-medical use
Due to their easy availability and affordability, research laboratories often use medical-grade syringes, such as cleaning hard-to-reach parts of the instrument and non-quantitative transfer solvents and reagents. Medical-grade syringes are generally made of polyethylene body, which is highly resistant to chemicals. However, the plasticizer contained in the syringe may seep out under the action of solvents. For this sensitive application, a glass syringe can be used instead. In anhydrous and anaerobic operation, the syringe can be used alone or in combination with tubing to facilitate the transfer of air-sensitive reagents such as Grignard reagent and n-butyl lithium that spontaneously ignite in air. In gas chromatography or mass spectrometry, samples are usually also loaded with a glass syringe. The former usually requires about 1 microliter, while the latter is 10 microliters.