HOW DO pH INDICATORS WORK? pH indicators detect the presence of H+ and OH-. They do this by reacting with H+ and OH-: they are themselves. weak acids and bases. If an indicator is a weak acid and is coloured and its conjugate base has a different. colour, deprotonation causes a colour change.
Have varicose veins, which are a common cause of superficial thrombophlebitis. Have a pacemaker or have a thin, flexible tube (catheter) in a central vein, for treatment of a medical condition, which may irritate the blood vessel wall and decrease blood flow. Are pregnant or have just given birth.
Thrombosis / Coronary Thrombosis. 1  The occlusion or blockage of blood flow within a vessel caused by blood that has clotted within the vessel. 2  Thrombosis of coronary arteries occurs when the opening, or lumen, of the artery becomes so small that the blood flow through the narrowed segment slows, allowing the blood to clot in the artery. Thrombosis of a coronary artery can lead to a heart attack if not treated.