Hemostatic valve

I. Percutaneous introducer kit sheath with hemostatic valve multiple sizes... 

II. Guide catheters multiple shapes and lengths ni. Hemostatic valves with optional flush system... 

Fig. 4.80 A. Lead delivery system with guide catheters. Hemostatic valve, guide wires and EP catheter. Courtesy Guidant/Boston Scientific. B. Family of guide catheters with multiple distal tip curves. Courtesy Medtronic Corporation. C. Hemostatic valve and flush system. Courtesy Guidant/Boston Scientific, (from Belott PH Implantation Techniques for Cardiac resynchronization Therapy Barold SS, Mugica J Fifth Decade of Cardiac Pacing. Armonk NY Futura. 2004 pp 10)...

More recently, a peel-away sheath with a hemostatic valve has been developed that completely avoids the problem of air embolization. 

Low-dose anticoagulant therapy is given concurrently with thrombolysis, mainly when the hemostatic valve sheath is placed in small veins, with a reduced flow. A total of 300 U/h heparin are infused continuously through the hemostatic valve sheath to keep the infusion catheter free from thrombi. Coagulation parameters are checked twice a day. 

Conventional Seldinger technique is generally used for the majority of the procedures, and a femoral sheath with hemostatic valve (4 to 9 French) is placed into the femoral artery to allow the exchange of the catheters, reducing the trauma to the artery. 

Hypercoagulable states, in turn, have been traditionally associated with venous thrombosis. Consequently, attention has been paid to alterations of the hemostatic balance. Although this is a systemic variable, focality is favored due to the contribution of decreased blood flow, as confirmed by the preferential development of venous thrombi at the level of valves, an area of stasis where low-velocity flow is moderately turbulent. 

Cardiopulmonary bypass, with extracorporeal circulation during cardiac artery bypass graft or heart valve replacement surgery, causes transient hemostatic defects in blood cells and perioperative bleeding. The protease inhibitor aprotinin (Trasylol) inhibits kalhkrein (coagulation phase) and plasmin (hbrinolysis) and protects platelets from mechanical injury. The overall effect after infusion is a decrease in bleeding. 

Make a small incision at the bottom apex of the left ventricle. Insert a blunt 13 G hypodermic needle upward through the ventricle past the aortic valve so that it can be visuahzed at approx 5 mm inside the ascending aorta. Clamp the needle in place with a hemostat across the ventricle. 

There is potential for aspiration of large quantities of air cansing air embolization with conscious sedation. This problem has been obviated by adequate patient preparation and utilization of sheaths incorporating h ostalic valves and guiding catheters equipped with hemostatic mechanisms. 

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