Manifold setup & function
Several setup steps are necessary before performing an angioplasty. Explaining the procedure and its need to the patient before obtaining informed consent, reviewing the latest blood tests, and inserting a venous cannula are done before entering the lab.
After laying the patient on the operating table the arterial access site is chosen and cleaned. The patient is then covered using a sterile drape, and the necessary materials are opened and placed upon a clean trolley.
The central piece of equipment is the Manifold system which requires assembly, purging and filling with contrast. The Manifold type and its particular configuration can vary according to local preference.
2. Manifold assembly
The Manifold acts as a switching stations that allows several fluid lines to connect to a single lumen that exits to the guide. Taps are used to control the direction of fluid flow, and a syringe attaches to allow controlled hand injections of contrast.
The Manifold can be two or three taps in length. The aim of the setup process is to make connections with the pressure transducing and contrast lines, to fill the system with contrast and saline, and to remove all air.
3. The Manifold taps
The Manifold taps control the direction of fluid flow, and they have a four arm design with the longer arm signifying the direction that is closed off. Typically, the most distal manifold tap that is closest to the exit port controls a flush and pressure transducing line. The proximal manifold tap that is closest to the syringe controls contrast flow on the contrast line and the syringe. The third tap in larger manifolds can serve as a drug giving or waste fluid removal line, and a three-way tap can add this function in smaller manifolds.
4. The extension
Interposing an optional extension line between the Manifold and the catheter has some advantages. It increases the distance between the manifold and catheter and allows the operator to stand further away after engaging the catheter into position. This extra distance can significantly reduce operator X-ray dosage, which is particularly important when performing procedures via the radial route. Also, the extra length acts to isolate the catheter from the Manifold movements when contrast is being drawn up or injected and can, therefore, improve catheter stability and avoid disengagement.