The Huber needle is a specialized medical device designed for repeated and safe access to long-term vascular access devices implanted beneath a patient’s skin. It allows healthcare providers to administer medications, fluids, or draw blood from a central vein over an extended period. This design maintains the integrity of the implanted device, unlike standard needles used for single injections, facilitating ongoing treatments like chemotherapy or long-term antibiotic therapy.
The Non-Coring Design
The distinctive feature of the Huber needle is its “non-coring” tip, engineered to part material rather than cut out a plug of it. Unlike a standard hypodermic needle, which creates a circular cut, the Huber needle has a deflected, or offset, bevel point. This geometry allows the needle to push the silicone septum material aside as it penetrates.
The opening for fluid delivery is located on the side of the needle shaft, slightly back from the tip, which enhances the non-coring action. This design prevents the needle from removing small pieces of rubber or silicone from the port’s internal seal, a process known as coring. Preventing coring preserves the device’s lifespan and prevents complications. Many Huber needles are also constructed with a 90-degree bend, allowing the attached tubing to lie flat against the skin for stability during continuous infusion.
Essential Role in Implanted Ports
The primary application for the Huber needle is accessing an implanted vascular access port, often called a Port-A-Cath or IVAD. This port is a small reservoir placed entirely under the skin, connected to a catheter leading into a large central vein. The port’s self-sealing membrane, or septum, is the point of access and is typically made of silicone or rubber.
The septum is designed to withstand a large number of punctures, often between 1,000 and 2,000, to accommodate long-term therapy. If a standard cutting needle were used, it would damage the septum, leading to fluid leakage, device failure, or potentially introducing foreign fragments into the bloodstream. The non-coring design ensures the septum can reseal itself completely after the needle is removed, maintaining a sterile barrier and preventing infection.
Insertion Procedure and Patient Care
Accessing the implanted port with a Huber needle is a procedure performed under strict aseptic technique to prevent infection. A healthcare professional first locates the port and its septum by gentle palpation through the skin. The area is then thoroughly disinfected, often with an alcohol-based chlorhexidine solution, before the needle is inserted.
The needle is inserted perpendicular to the port until the tip reaches the back wall of the reservoir. A topical anesthetic may be applied 30 to 60 minutes prior to minimize discomfort. Once proper placement is confirmed, typically by drawing blood, the port is flushed using a pulsatile, “push-pause” technique to ensure patency and prevent occlusion. The needle is then secured with a sterile dressing and can remain inserted for several days for continuous or intermittent infusions.