A TRUE CIRCLE CONVERSION OF THE "C-M " ABSORBER UNIT BY

T H E advent of halothane has led to some revival of interest in inhalation anaesthesia with spon-taneous respiration, muscular relaxation being obtained by deepening the plane of narcosis rather than by the use of specifically relaxant drugs. In cases so conducted significant alveolar accumulation of carbon dioxide must follow the inevitable respiratory depression. This is especi-ally so when a completely closed circuit technique is used—probably due to the absence of the flushing effect produced in the respiratory tract by the high gas-flow normally employed in semi-closed systems. A series of more than 5,000 patients having closed circuit halothane anaesthesia was closel