Stent Lock Mechanism for Transcutaneous Catheters

描述(由申请人提供)： 腹膜透析、化疗的血管内通路、心脏电源线的经皮胸腔通路和耻骨上膀胱引流是治疗过程中常规使用经皮导管的临床应用。虽然这些设备在短期内表现良好，但有效的长期使用是有限的。传统的经皮导管并不是水密的，这些开放的生态系统允许皮肤微生物沿着导管迁移到体内。腹膜透析导管的进展试图通过将导管的多孔同种异体组件植入体壁来关闭开放的生态系统。然而，如果感染发生在导管沿线或腹膜内，则需要手术移除并更换导管。对于耻骨上膀胱引流，已经实施了类似但明显不同的研究方法。这种组织粘结式膀胱造瘘术(TBC)是需要一种安全、可逆的锁定机制的一个临床例子，这种锁定机制将在内嵌锚定组件和通过锚定进入膀胱的经皮引流管之间产生坚固、水密、可逆的锁定。同样的原则从尿液引流延伸到腹膜透析、慢性血管通路和慢性胸腔内通路。坚固、可靠、易逆转、水密的锁定机构的概念证明是开发具有广泛医疗应用的经皮进入装置的第一步。 因此，提出了一种使用形状记忆合金丝的支架锁机构的创新设计，该合金丝具有独特的性能，非常适合提供安全的可逆锁。该机构不是机械干涉配合，而是使用高摩擦力将导管牢牢固定在适当的位置。由于它完全封闭在引流导管的管壁内，因此没有任何部位暴露在周围的组织或液体环境中。这种支架锁定机制将在第一阶段开发，用于耻骨上TBC尿路植入物的概念验证。将修改现有的锚件，并开发两种工具来锁定和解锁锚中的导管。摩擦力的大小将通过实验评估，以及将锁定和解锁的导管从锚定中移除所需的拔出力。第一阶段的成功将导致第二阶段的动物研究和其他经皮途径应用的概念的修改。

DESCRIPTION (provided by applicant): Peritoneal dialysis, intravascular access for chemotherapy, transcutaneous intrathoracic access of cardiac power lines, and suprapubic bladder drainage are among the clinical applications where transcutaneous catheters are routinely used in the course of treatment. Although these devices perform well for short durations, effective long-term use is limited. Traditional transcutaneous catheters are not watertight, and these open ecosystems permit skin microbes to migrate along the catheter into the body. Advances in peritoneal dialysis catheters attempt to close the open ecosystem with the implantation of a porous alloplastic component of the catheter into the body wall. However, should infection occur along the catheter or within the peritoneum, surgery is required to remove and replace the catheter. A similar, but significantly different investigational approach has been implemented for suprapubic drainage of the urinary bladder. This tissue-bonded cystostomy (TBC) is one clinical example of the need for a secure, reversible locking mechanism that will create a robust, watertight, reversible lock between an ingrown anchor component and the transcutaneous drainage tube that passes through the anchor into the urinary bladder. The same principle extends beyond urinary drainage to peritoneal dialysis, chronic vascular access, and chronic intrathoracic access. Proof of concept of a robust, reliable, easily reversible, watertight locking mechanism is the first step in development of a transcutaneous access device with broad medical applications. Accordingly, an innovative design is proposed for a Stent Lock mechanism that uses a shape-memory-alloy wire with unique properties ideally suited to provide a secure, reversible lock. Instead of a mechanical interference fit, the mechanism uses high friction force to hold the catheter firmly in place. Since it is totally enclosed within the walls of the drainage catheter, no part is exposed to the surrounding tissue or fluid environment. This Stent Lock mechanism will be developed in Phase I for proof of concept in a suprapubic TBC urinary implant. An existing anchor element will be modified, and two tools developed to lock and unlock the catheter in the anchor. The magnitude of friction forces will be experimentally evaluated along with the pullout force necessary to remove the locked and unlocked catheter from the anchor. Success in Phase I will lead to animal studies in Phase II and modification of the concept for other transcutaneous access applications.