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.
Article Sections. Postpartum hemorrhage is a significant cause of maternal morbidity and mortality. Most postpartum hemorrhages are caused by uterine atony and occur in the immediate postpartum period. Expectant or physiologic management of the third stage of labor has been compared with active management in several studies.