(Part 1 by Frey & Gruber; Part 2 by Frey.) Frey and Gruber developed the first heart-lung machine. Their machine "consisted of a double-acting pump in the form on an injection syringe with a capacity of 10 ml, which imitated the heart action and two values. This pumping system produced a pulsatile flow. Because of this pulsatile driving force, 'as a result of the swing mvoement of the blood elements and through the constant change of the vessel diamenter, obstructions occurred les freqeuently and resolved quicker, as sedimentation and adhesions of the cells happened to a lesser extent.'

"An important component of this artificial circulation was the addition of the facility 'which was able to replace the lung.'  Von Frey...developed the first film oxygenator for this purpose. Blood in the form of a thin film was oxygenated inside a slowly rotating cylinder by an oxygen atmosphere. The temperature of the arterial blood was regulated by a 'preheater.' As with current heart-lung machines, the circulation incorporated several pressure and temperature measuring devices as well as sample ports. By insertion of glass cannulae into both the aorta and vena cava, artificial perfusion of a dog's rear part was performed. Following elecrical muscle stimulation during this experiment, measurements of 'the consumption of oxygen caused by its use by the tissue and the absorbed carbon dioxide' were performed, as stated in their reports dated 20 November, 1883" (Boettcher, W., Merkle, F., Weitkemper, H-H.," History of extracorporeal circulation: The conceptional and developmental period,", J. Amer. Soc. Extra-Corporeal Technology," 35 (2003) 172-183, quoting from p. 175).
See also Zimmer,H-G., "The heart-lung machine was invented twice--the first time by Max von Frey," Clin. Cardiol., 26 (2003) 443-45.