An angiocath is a short, flexible plastic tube designed to sit inside a vein and deliver fluids, medications, or blood products directly into the bloodstream. It’s one of the most common medical devices in the world, used in everything from routine IV drips to emergency trauma care. The name “Angiocath” is actually a brand name from BD (Becton, Dickinson and Company), but it’s used so widely in hospitals that many healthcare workers use it as a generic term for any peripheral IV catheter.
How an Angiocath Is Built
An angiocath is an “over-the-needle” catheter, meaning it arrives as two pieces fitted together: a hollow steel needle on the inside and a thin, flexible plastic tube (the catheter) wrapped around it on the outside. The needle is only there to puncture the skin and vein wall. Once the catheter is threaded into the vein, the needle is pulled out and discarded, leaving just the soft plastic tube behind.
At the back end of the device is a small transparent chamber called the flash chamber. When the needle enters a vein, blood flows back into this chamber, giving the person placing the IV a visual confirmation that they’ve hit the right spot. BD’s version uses a clear flash chamber specifically designed to make that blood return easy to see. A plastic hub at the base of the catheter connects to IV tubing or a syringe once the needle is removed.
The catheter itself is made from one of two materials: a Teflon-based polymer or polyurethane. Both are flexible enough to sit comfortably inside a vein without puncturing the vessel wall. Polyurethane catheters are associated with a lower rate of vein inflammation, and studies have shown they perform reliably across a wide range of temperatures. The soft material lets the catheter flex with the patient’s movement, which is why it can stay in place for days without causing damage.
Why Gauge Size Matters
Angiocaths come in several sizes, measured in gauge. The gauge number works in reverse: a lower number means a larger catheter. Each size is color-coded at the hub so healthcare workers can identify it at a glance. The size chosen depends on why the patient needs IV access and how fast fluids need to flow.
- 14 gauge (orange): The largest standard size at 2.1 mm wide. Delivers up to 240 mL per minute. Reserved for major trauma or massive fluid replacement.
- 16 gauge (gray): 1.7 mm wide, flowing at about 180 mL per minute. Common in surgery and situations requiring rapid volume replacement.
- 18 gauge (green): 1.3 mm wide with a flow rate around 90 mL per minute. The go-to for blood transfusions and moderate fluid resuscitation.
- 20 gauge (pink): 1.1 mm wide at roughly 60 mL per minute. The workhorse for routine IV fluids and medications.
- 22 gauge (blue): 0.9 mm wide, flowing at about 35 mL per minute. Often used for elderly patients, children, or slower infusions.
- 24 gauge (yellow): The smallest at 0.7 mm wide and 20 mL per minute. Designed for newborns and patients with very fragile veins.
For most adults receiving standard medications or fluids, a 20-gauge catheter is sufficient. Larger sizes are selected when speed is critical, such as replacing large volumes of blood or fluid in an emergency. Smaller sizes are gentler on delicate veins but limit how quickly fluids can be delivered.
What It’s Used For
The most common reason for placing an angiocath is to deliver medications and fluids intravenously. This includes everything from antibiotics and pain medication to saline for dehydration or chemotherapy drugs. Patients who can’t take medications by mouth, who are hemodynamically unstable, or who need electrolyte correction typically get one placed early in their care.
Angiocaths also serve as access points for drawing blood. Healthcare workers often collect blood samples at the time of insertion, before any fluids or medications flow through the line, to avoid contaminating or diluting the sample. Beyond standard IV use, angiocaths can be placed in arteries for continuous blood pressure monitoring. For arterial placement, a clinician inserts the catheter at a 30- to 45-degree angle into the radial artery at the wrist, using a 22-gauge catheter for most adults and a 24-gauge for very small infants.
How Insertion Works
The process starts with selecting a vein, usually on the back of the hand or the inside of the forearm. A tourniquet is tied above the site to make veins more visible and easier to access. After cleaning the skin, the clinician inserts the needle at roughly a 30-degree angle. As soon as blood appears in the flash chamber, confirming the needle is inside the vein, the angle is lowered and the plastic catheter is slid forward off the needle and into the vein.
The needle is then withdrawn entirely. Modern angiocaths include safety-engineered features that retract or shield the needle automatically once it’s removed, reducing the risk of accidental needlestick injuries for healthcare workers. The catheter hub is then secured to the skin with adhesive dressing, and IV tubing or a saline lock is attached. The entire process takes less than a minute in experienced hands, though it can take longer in patients with difficult veins.
Common Complications
Peripheral IV catheters are generally safe, but complications do occur, especially the longer a catheter stays in place.
Infiltration is one of the most frequent problems. It happens when the catheter shifts out of the vein and fluid leaks into the surrounding tissue. Signs include swelling, tightness, and cool skin around the insertion site. The IV may slow down or stop flowing altogether, and fluid may visibly leak from around the catheter. Infiltration with a standard solution like saline is uncomfortable but resolves once the IV is removed. Extravasation is the more serious version, occurring when an irritating medication leaks into tissue. It can cause burning, blistering, and in severe cases, tissue damage.
Phlebitis, or inflammation of the vein lining, causes redness, warmth, pain, and sometimes a firm, cord-like feeling along the vein. It can develop from the mechanical irritation of the catheter, from certain medications, or from infection. Local infection at the insertion site typically appears two to three days after placement, marked by redness and drainage. Minor bleeding from the site is common and usually stops with pressure. Nerve irritation during or after insertion, felt as a tingling or shooting sensation, can indicate the catheter is pressing on a nerve.
Most of these complications are caught quickly by nursing staff during routine checks of the IV site. When any complication is identified, the catheter is removed and a new one is placed at a different location if IV access is still needed.
Angiocaths vs. Other IV Access
An angiocath is a peripheral IV catheter, meaning it sits in a surface-level vein, typically in the arm or hand. It’s the simplest and fastest form of IV access to establish. For patients who need IV therapy for more than a few days, or who require medications that are too harsh for small veins, doctors may place a central line or a PICC line instead. These longer catheters thread through larger veins and terminate near the heart, allowing them to handle higher concentrations of medication and remain in place for weeks or months.
For short-term needs like a course of IV antibiotics, surgery, an ER visit, or fluid replacement for dehydration, a standard angiocath is almost always the first choice. It’s quick to place, easy to maintain, and can be removed in seconds when it’s no longer needed.