Ludwig, Carl F W

Ludwig, Carl F(riedrich) W(ilhelm)

(born Dec. 29, 1816, Witzenhausen, near Kassel, Hesse-Kassel—died April 23, 1895, Leipzig, Ger.) German physician. He invented devices to record arterial blood-pressure changes, measure blood flow, and separate gases from blood (which established their role in blood purification). He was the first to keep animal organs alive outside the body. His paper on urine secretion in 1844 hypothesized a filtering role for the kidney. Nearly 200 of Ludwig's students became prominent scientists, and he is regarded as the founder of the physicochemical school of physiology.