“…Warren, Fomon & Leite (1968) studied three patients and found mean pressures of 14, 9 and 12 mm Hg The duct pressure was usually equal to or slightly higher than the central venous pressure. The end pressure in the human thoracic duct has been reported to be between 20 and 30 mm Hg (Shafiroff & Kan, 1959;Ross, 1961) and some workers (Edwards, Gough, Kinmonth & Pierce, 1965;Tilney & Murray, 1968) have observed fluctuations of pressure, in addition to the respiratory and pulse waves, occurring every 10-20 sec which they attributed to spontaneous contractions of the duct.…”