If you have had or are preparing for a catheter-based procedure, your medical team may have mentioned an "introducer sheath." This small but essential device plays a central role in nearly every vascular procedure, from diagnostic angiograms to more involved interventional treatments. Understanding what an introducer sheath does can help you feel more informed about your upcoming procedure.
What Is an Introducer Sheath?
An introducer sheath is a short, hollow tube that is placed into a blood vessel, usually through the wrist, groin, or foot, to create a stable pathway for other devices to enter and exit the vessel. Once in place, it allows a physician to pass catheters, guidewires, and other tools into the vascular system repeatedly during a procedure without needing to puncture the skin and vessel each time.
Introducer sheaths are typically inserted using a technique called the Seldinger technique, in which a needle, guidewire, and dilator are used together to establish access before the sheath itself is advanced into the vessel.
Why Are Introducer Sheaths Used?
Introducer sheaths serve several important functions during a procedure:
- Stable access: They keep the puncture site open and stable, so tools can be exchanged smoothly.
- Reduced blood loss: A hemostatic valve built into the sheath is designed to minimize bleeding around the device as it enters and exits.
- Contrast and medication delivery: Many sheaths include a side port that allows fluids, contrast media, or medications to be introduced without removing the sheath.
- Protection of the vessel: By providing a smooth, controlled channel, sheaths are intended to reduce trauma to the vessel wall compared to repeated direct instrumentation.
What Does "French Size" Mean for a Sheath?
Introducer sheaths are sized using the French (Fr) scale, a measurement of the outer circumference of the device. Larger French sizes accommodate larger catheters and devices, while smaller French sizes are generally used for diagnostic procedures or smaller vessels. Your physician selects the sheath size based on the devices needed for your specific procedure and your vascular anatomy.
What Happens When the Sheath Is Removed?
At the end of a procedure, the introducer sheath is removed, and the access site requires hemostasis, meaning the bleeding must be controlled and stopped. This may be achieved through manual compression, a mechanical compression device, or, in some cases, a vascular closure device. Your care team will monitor the site and provide instructions for aftercare.
INVAMED Introducer Sheath Design
INVAMED manufactures introducer sheath systems, including the INVADUCER sheath set, which is designed as a complete kit with a dilator, guidewire, syringe, and a sheath featuring a hemostasis valve and side port. INVAMED also offers the Jaguar guiding sheath, a reinforced, kink-resistant design intended to combine the functions of an introducer sheath and a guiding catheter for peripheral, renal, and carotid access. These devices are intended for use by trained healthcare professionals.
Frequently Asked Questions
Does having an introducer sheath placed hurt?
Local anesthesia is typically used at the insertion site before the sheath is placed, which is intended to minimize discomfort. Some patients report feeling pressure. Ask your care team what to expect for your specific procedure.
How long does an introducer sheath stay in place?
The sheath usually remains in place only for the duration of the procedure and is removed once your physician has completed the necessary steps. In some cases, a sheath may be left in place briefly afterward; your care team will explain the plan for your situation.
Can an introducer sheath be used for more than one type of procedure?
Introducer sheaths are generally selected based on the specific procedure, vessel, and devices required. Your physician determines the appropriate sheath type and size for your individual case.
Related INVAMED Resources
- Comprehensive Catheter & Guidewire Systems
- Peripheral Arterial Disease (PAD)
- Request Information from INVAMED
Medical Disclaimer: This article is provided for general informational and educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendation. It is not a substitute for consultation with a qualified healthcare professional. Product indications, availability, and regulatory status vary by country. Always refer to the official Instructions for Use (IFU) and consult a licensed physician for guidance specific to your situation. INVAMED devices are intended for use by trained healthcare professionals.