Tourniquets: Devices for the compression of a blood vessel by application around an extremity to control the circulation and prevent the flow of blood to or from the distal area. (From Dorland, 28th ed)Hemostasis, Surgical: Control of bleeding during or after surgery.Anesthesia, Conduction: Injection of an anesthetic into the nerves to inhibit nerve transmission in a specific part of the body.Blood Loss, Surgical: Loss of blood during a surgical procedure.Arthroplasty, Replacement, Knee: Replacement of the knee joint.Anesthesia, Intravenous: Process of administering an anesthetic through injection directly into the bloodstream.Ischemia: A hypoperfusion of the BLOOD through an organ or tissue caused by a PATHOLOGIC CONSTRICTION or obstruction of its BLOOD VESSELS, or an absence of BLOOD CIRCULATION.Operating Room Technicians: Specially trained personnel to assist in routine technical procedures in the operating room.Orthopedic Procedures: Procedures used to treat and correct deformities, diseases, and injuries to the MUSCULOSKELETAL SYSTEM, its articulations, and associated structures.Arm: The superior part of the upper extremity between the SHOULDER and the ELBOW.Phlebotomy: The techniques used to draw blood from a vein for diagnostic purposes or for treatment of certain blood disorders such as erythrocytosis, hemochromatosis, polycythemia vera, and porphyria cutanea tarda.Leg: The inferior part of the lower extremity between the KNEE and the ANKLE.Prilocaine: A local anesthetic that is similar pharmacologically to LIDOCAINE. Currently, it is used most often for infiltration anesthesia in dentistry.