Syringes are categorized based on their design, use, and functionality. Common types include:
General-Purpose Hypodermic Syringes
- Description: These are standard hypodermic syringes used for general medical purposes, such as administering medications or withdrawing fluids from the body. They consist of a cylindrical barrel, a plunger, and an attached or detachable needle.
- Applications: Routine injections, blood draws, vaccinations, etc.
Insulin Syringes
- Description: Syringes specifically designed for the administration of insulin. They have finer needles and are marked in insulin units rather than milliliters.
- Applications: Self-administration of insulin by diabetic patients.
Tuberculin Syringes
- Description: These are small-volume syringes used for intradermal injections, commonly for tuberculosis (TB) testing. The barrel is marked in millilitres up to 1 mL.
- Applications: Tuberculin testing, allergy testing, or other intradermal injections
Luer Lock Syringes
- Description: Syringes with a Luer lock fitting that allows for a secure connection between the syringe and the needle or other devices.
- Applications: Intravenous injections, procedures where a secure needle connection is necessary.
Irrigation Syringes
- Description: Syringes used for wound irrigation, ear irrigation, or similar non-injection purposes. They typically have a blunt tip or no needle.
- Applications: Wound cleaning, ear, and nasal irrigation.
Catheter Tip Syringes
- Description: Syringes with a long, tapered tip designed to attach to catheters or tubing rather than a needle.
- Applications: Flushing catheters, feeding tubes, wound irrigation.
Safety Syringes
- Description: Syringes incorporate a safety mechanism to prevent needlestick injuries, such as retractable needles or needle shields.
- Applications: Administration of medications where needlestick injury prevention is important.
Auto-Disable Syringes
- Description: Syringes are designed to disable themselves after a single use to prevent reuse, helping to reduce the spread of infectious diseases.
- Applications: Vaccination campaigns, especially in settings where syringe reuse is a concern
The barrel is the main body of the syringe, a cylindrical tube that holds the fluid to be injected or withdrawn. It is usually made from transparent materials such as plastic (e.g., polypropylene) or glass, allowing the user to see the fluid inside. The barrel is marked with graduation lines that indicate the volume of fluid, ensuring accurate dosing.
Plunger:
The plunger is a rod that fits tightly within the barrel and is used to draw fluid into or expel fluid from the syringe. It is often made of plastic and has a rubber or silicone tip to create a seal with the barrel. When the plunger is pulled back, it creates a vacuum that draws fluid into the barrel; when pushed forward, it expels the fluid.
Plunger Seal (Piston):
Located at the end of the plunger, the plunger seal, or piston, is typically made of rubber or another flexible material. This component ensures a tight seal with the barrel, preventing leakage of the fluid during use and ensuring smooth movement of the plunger.
Nozzle (Tip):
The nozzle, or tip, is located at the narrow end of the barrel and is designed to attach to a needle, IV line, or other medical apparatus. Syringes can have different types of nozzles, such as Luer Lock (which screws onto the needle for a secure connection) or Luer Slip (where the needle is pushed on). The choice of nozzle type affects the security of the attachment and the intended use of the syringe.
Needle (if included):
In many cases, the syringe includes a needle attached to the nozzle. The needle is typically made of stainless steel and varies in length and gauge depending on the application. It is designed for penetrating the skin or other tissues to deliver or withdraw fluids. Some syringes are sold without needles, allowing the user to select and attach the appropriate needle for their needs.
Flange:
The flange is the flat, wing-like extension at the open end of the barrel where the plunger is inserted. It provides a surface for the user to press against while operating the syringe, making it easier to push or pull the plunger.
Cap (Optional):
Some syringes come with a cap that covers the nozzle or needle, maintaining sterility until the syringe is used. The cap is typically made of plastic and can be either a separate component or integrated into the syringe design.
