Cannula is a specially designed flexible tube that looks like a needle and that can be inserted into the human body much easily than a conventional needle. They are also designed to minimize the possible hit and miss needle insertions into the veins of patients. For medical use there are 11 different types of cannulas. The most commonly used are the intravenous and the nasal cannulas.
Sizes and insertion
Cannulas are widely used at hospitals and clinics worldwide to perform an administration of intravenous fluids such as liquid medicines, as well as to draw blood samples from patients. The come in a variety of sizes from small 24-gauge to 14-gauge size that are used in trauma environments. With a large cannula, doctors can administer up to 1 liter of fluid in under two minutes. The standard widely used units that doctors use at hospitals are the 20-gauge size, which are frequently used for administering fluids such as antibiotics. For patients with small and more fragile veins, doctors usually use a 22-gauge size. For patients that are difficult to insert doctors usually utilize the 14-gauge size units.
The general rule for cannulation is that doctors attempt to insert the cannula lure down the arm and then work their way up towards the antecubital fossa, however, if it’s a patient who has suffered a cardiac arrest or is a trauma victim, doctors attempt to make the insertion in a larger vein higher up the arm where the antecubital fossa area may be suitable. Certain patients have restrictions where doctors can perform the cannulation, this includes patients who have mastectomy or patients who have got renal fistula in both of those circumstances doctors try to avoid the arm affected. Careful insertion of the cannula and early identification, as well as interventions, are found to prevent severe adverse events, such as extensive tissue injury or nerve injury that may require even a surgical intervention.
Additional benefits of using cannulas is that they have soft and flexible wings. They are very easy to use. The integrated injection port enables hygiene and needle free injection and administration of medication.
· Luer cap
· Needle Grip
· Removable flash plug with filter
· Clear flashback chamber
· Safety shield
· Injection port cap
· Curvy and flexible hub and wings
· Radio-opaque catheter
· Tri sectional bevel
How cannulas work
Specially designed bevels create a V shaped incision, that create an adaptable pathway for easy and smooth insertion of the catheters. Usually results are less tearing and faster healing, greater comfort for doctors and nurses as well as for patients. Some units have a special design that improve the first stick success through quick visualization of both the needle flash and the catheter. Upon insertion the first flashback of blood needle flash is visible through a clear flashback chamber, confirming that the cannula needle tip is in the vein. Using a specially designed push-off plate on the hub of the catheter is pushed forward off the needle into thee vein. The second flashback catheter flash occurs between the catheter and the needle, confirming that the catheter has successfully penetrated the vein. Once the catheter is fully advanced the needle is withdrawn in a swift continuous motion.
The safety shied engages as the needle tip passes through the catheter hub that deploys automatically and provides a permanent shield from the needle tip. This safety feature cannot be bypassed, and it’s designed to protect against needle stick injures. The removable vented flash plug provides additional versatility to the IV catheter. On most units the plash plug can be replaced with a syringe or blood collection access device prior to insertion or even loosened to speed blood return during catheter insertion. After needle removal these features allow doctors and nurses to obtain a droplet of blood to procedures such as monitoring glucose or hemoglobin levels.