2 The technology

Technology

2.1 Danis stent is a self-expanding and removable stent used to stop acute bleeding from oesophageal varices. The stent is a variable weave, made of nitinol with a silicone membrane. It is 135 mm long and 25 mm in diameter at the centre, increasing to 30 mm in diameter at the flared distal ends. During insertion, a balloon is inflated in the stomach to make sure the stent self-expands in an accurate position at the gastro-oesophageal junction, providing direct compression of oesophageal varices. The aim of Danis stent is to stabilise the bleeding, until the person can have definitive treatment to manage the underlying problem. Features of the stent include radiopaque markers for visibility, a security pressure valve and retrieval loops with gold markers. The company recommends that Danis stent stays in place for no longer than 7 days. A specially designed removal device, the Ella extractor, is needed to remove the stent unless a definitive treatment has been done, in which case the risk of re-bleed may be considered low and the stent may be removed with grasping forceps.

Innovative aspects

2.2 The company states that Danis stent can be used without direct endoscopic imaging, which may allow for more rapid control of variceal bleeds in emergency situations compared with balloon tamponade. The delivery system has a security pressure valve that prevents the gastric balloon from being inflated in the oesophagus, which may help minimise the risk of oesophageal perforation. The stent can stay in place for up to a week (compared with balloon tamponade, which should not be left in place for more than 24 hours to 36 hours). This may allow more time to plan definitive therapy (such as transjugular intrahepatic portosystemic shunt [TIPS] insertion, usually done more than 72 hours after Danis stent insertion) or secondary band ligation. It may also keep the bleeding stable for longer, allowing liver function to improve. Danis stent keeps the oesophagus open, allowing oral nutrition to be maintained, which is an important element in recovery. Its variable weave stent body is designed to conform to oesophageal peristalsis, with the aim of preventing stent migration.

Intended use

2.3 Danis stent is intended for use in acute refractory oesophageal variceal bleeding, after first-line therapy, such as variceal band ligation, has failed, to allow more time for a definitive procedure to be done. It is intended to be used as an alternative to balloon tamponade or early TIPS insertion (that is, done within 72 hours), in people aged 16 and over.

2.4 The technology is intended to be used in secondary or tertiary care by gastroenterologists, hepatologists, emergency care practitioners, paramedics or nurse practitioners. Comprehensive training is needed and is delivered by the company.

Costs

2.5 The cost of Danis stent is £1,495 (excluding VAT) per stent. The cost of the Ella extractor is £695 (excluding VAT).

For more details, see the website for Danis stent.

  • National Institute for Health and Care Excellence (NICE)