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A TEXTBOOK OF PHYSIOLOGY 



oxide and nitrite, etc.) and in eases of drowning, suffocation and 

 chloroform syncope (Fig. 182). To carry out the method most effec- 

 tively there would be required an anaesthetic mouth-piece and rubber 

 bag rilled with oxygen in and out of which the operator has respired 

 several times. This is then given the patient to breathe while arti- 

 ficial respiration is done. To respirate children artificially it is best 

 to put mouth to mouth (interposing a handkerchief) and rhythmically 

 blow up the lungs. A hand placed on the belly prevents the stomach 



J^'iG. 184. THE VIVATOR APPARATUS FOR ARTIFICIAL RESPIRATION. 

 (Siebe, Gorman and Co.) 



The apparatus consists of a special pump, which, on the downstroke, delivers oxygen 

 from a bag (connected to an oxygen cylinder) into the inspiratory tube of a 

 mask, which is fastened or held tightly over the patient's nose and mouth. 

 Having completed the downstroke and so forced oxygen into the patient's 

 lungs, the pump on its return or upstroke not only sucks in a fresh supply of 

 oxygen to be delivered on the next downstroke, but also opens a valve, which 

 is connected with the expiratory tube of the mask, thus allowing the expiratory 

 recoil of the expanded chest and lungs of the patient free play. The valve 

 remains open during the upstroke and automatically closes when the stroke is 

 completed. The piston of the pump then descends and delivers another supply 

 of oxygen, and so on. 



being blown up, or the gullet can be closed by pressing the larynx 

 backwards. A pump has been contrived for this purpose, fitted with 

 a face mask (Fig. 184). The stroke of the piston is arranged to open 

 a valve at the end of the inflation so as to allow deflation of the lungs 

 by the elastic recoil of the thorax. Such a pump cannot be used to 

 suck air out of the lungs, for suction causes the walls of the small 

 bronchial tubes to come together, and does not empty the alveoli. 



