Choosing the Right Needle

Tenko Medical hypodermic needles

There are three main types of medical needles that can be used for injections, samples and sutures.

Injection needles

There are two main injection routes: hypodermic and intravenous.

• Hypodermic needles: allow the administration of a drug in injectable form into the patient’s subcutaneous cellular tissue. This type of injection can be performed in hospitals, clinics, care centers or even at home. The needles are used with a prepared syringe. There are special devices, called injection pens, that allow you to easily and accurately adjust the dose injected. In this case the medication comes in the form of pre-filled cartridges, which prevents having to take the dose from a bottle. The needle must be replaced after each use. This type of needle is commonly used for insulin injections or certain anticoagulants.
• Intravenous injection needles : allow the administration of a liquid, often a drug solution, directly into a vein. A tourniquet is placed ten centimetres above the injection site. Intravenous injections allow for a faster therapeutic effect than hypodermic injections. They also avoid the risk of reactions with subcutaneous or muscle tissue (which can cause pain, edema or even necrosis in extreme cases).

Sample needles

These needles are used for two main types of sampling:

A Mopec Europe suture needle

• Blood samples: in the case of blood samples by venipuncture or arterial puncture, the use of a tourniquet may be necessary to make the vein protrude. Some blood sample or infusion needles are equipped with a premounted adapter to connect to a sample body.
• Biopsies: most biopsy needles are extremely thin and strong, as in the case of a lumbar puncture needle for example. For this procedure, the needle penetrates deep into an intervertebral space in the lumbar spine and punctures the dura mater, the rigid fibrous membrane that protects the spinal cord. A sample of cerebrospinal fluid is taken to detect the presence of certain diseases, such as bacterial meningitis. This is performed under local anesthesia.

Surgical suture needles: allow, as their name indicates, the suture of different types of tissue by means of a suture that may or may not be absorbable.

A Sterylab biopsy gun

Depending on the type of needle you are looking for, a series of criteria must be taken into account before making your choice.

• For injection and sample needles:
  • What will it be used for?
  • What size and diameter will you need?
  • What syringe volume?
  • Do you need one needle alone or a complete set?
  • Safety needle or not?

• For biopsy needles:
  • What type of tissue will be sampled (hard or soft)?
  • What is the penetration depth?
  • Sample size?
  • Manual or automatic needle (biopsy gun type)?
  • Marking on the cannula or not?
  • Echogenic needle (in the case of ultrasound-guided biopsies) or not?

• For suture needles:
  • What type of tissue will be sutured?
  • What is the diameter of the needle and thickness of the thread?
  • What is the resorbability of the thread (short term, medium term, non resorbable, etc.)?

A Vogt Medical Vertrieb safety needle

Safety needles are equipped with a safety guard to prevent any risk of accidental pricking during handling. They offer active protection to the user. They can have several characteristics:

• A device to secure the needle after use: this device may or may not be attached to the needle. Depending on the supplier, some needles have the feature of being protected by a cap or retracting once the injection is complete.
• Irreversible needle covering: this type of device offers a total and irreversible covering of the needle with two locking points. The locking of the safety device is indicated by a double click sound: a first click when assembling on the tip syringe; a second click when activating the safety device. The system is then irreversibly locked.

A D.R.M. medical kit for fistula needle disposal

There are several rules to follow after using a syringe, as well as different options for disposing of them. Here are the main steps to follow:

• Do not recap a used syringe
• Do not attempt to manually bend or break a syringe before disposal
• It is possible to use a needle destroyer before disposing of the syringe
• Needles, like any dirty sharp object, should be placed in a special container or appropriate medical waste bin immediately after use. These containers or medical waste bins should be rigid and marked with a contamination sign indicating the nature of the waste contained
• Do not overfill the container or bin and respect the filling limit indicated.