PULMOTOR, a machine invented by Ber nard Draeger for producing artificial respira tion. It was first used in Europe in connection with mine rescue apparatus. Later it was used by the United States Bureau of Mines in similar work. It was found to be so satisfactory in resuscitating after all kinds of suffocation, such as asphyxiation from gas, electric shock and cases of apparently drowned, that large gas and electrical companies have installed them; also many hospitals and fire and police departments.
Formerly in cases of asphyxiation, morphine poisoning, drowning, or electric shocks, efforts to restore respiration consisted in laying the patient on his back and alternately pulling his arms over his head and forcing them down upon his chest, thereby causing an expansion of the lung cavity, and then compressing it, thus first producing artificial breathing. In such cases it became necessary to force the patient's mouth open and pull out his tongue, thereby affording free passage for the which alternately, was drawn into the lung cavity and immediately expelled. This process is super seded by the application of the pulmotor, which operates as follows: An iron cylinder 3;4 x 21 inches contains the oxygen at a pressure of about 2,250 pounds when completely filled and will operate the pulmotor 40 minutes con tinuously. This life-sustaining Fas also fur nishes the energy which is required to induce breathing, in the following manner: The oxygen from the tank flows through a re ducing valve, which at the outlet side main tains a pressure of about 75 pounds, and from there to the controlling valve, Initially, the passage to the lungs is open through this con trolling valve. The latter connects two flexible
braided copper tubes, leading to a metallic face cap with a rubber rim, which dopey fits the patient's face. The patient's tongde is drawn down over the lower jaw and under the mask, by means of a set of tongue forceps which is provided. The oxygen then has free access to the lungs.
When the pressure in the lungs has reached a certain value, 20 centimeters, a bellows inter connected with the lung cavity through the flexible braided copper actuates the controlling valve. The pressure of oxygen is now directed so as to create a suction over the connections which lead to the lungs, thereby causing ex halation of the gases previously forced into the lungs. When a vacuum of 25 centimeters is reached in the lungs and belloWs, the outer atmosphere acts on the latter, in turn operates the controlling valve and again admits the oxygen to the lungs. The frequency of these reversals depends upon the size of the lung cavity, a larger space requiring greater time, while with smaller lung cavities the opera tion is correspondingly more frequent. This process is continued until the patient shows signs of natural respiration. The pulmotor action is then discontinued and the patient is allowed to breathe the pure oxygen through another small face cap connected by a hose directly to the oxygeh tank.