Ringer’s solution, one of the first laboratory solutions of salts in water shown to prolong greatly the survival time of excised tissue; it was introduced by the physiologist Sidney Ringer in 1882 for the frog heart. The solution contains sodium chloride, potassium chloride, calcium chloride, and sodium bicarbonate in the concentrations in which they occur in body fluids. If sodium lactate is used instead of sodium bicarbonate, the mixture is called lactated Ringer’s solution. This solution, given intravenously, is used to rapidly restore circulating blood volume in victims of burns and trauma. It is also used during surgery and in people with a wide variety of medical conditions. Mammalian Ringer’s solution (Locke’s, or Ringer-Locke’s, solution) differs in that it contains glucose and more sodium chloride than the original solution.