Double Lumen Catheter for Intravenous and Intracardiac Blood Sampling and Pressure Recording.

Summary1. Simultaneous blood samplings and pressure recordings in 2 continuous segments of the circulatory system may be obtained in man by means of a specially designed double-lumen catheter. 2. The difference in oxygen content of 2 blood samples withdrawn simultaneously from 2 points located 10 cm apart in the right auricle and right ventricle was well within the limits of technical error in 8 out of 9 cases. 3. Examples are given of the recording of simultaneous mechanical events in (a) the right auricle and ventricle, (b) the right ventricle and the pulmonary artery.