X-Ray Study of Passage of Air Through the Pharynx in Anaesthetised Patients

The Immediate Treatment of Respiratory Failure

“…To investigate this, 3,676 subjects were examined for their ability to breathe through the nose (Ruben, 1961a). A less than 2 per cent incidence of nasal blockage was found, which is in agreement with other findings (Buchanan, 1960).…”

“…In the first case, where the mandible is pulled up against the maxilla though, as mentioned, without forward displacement, an important advan-tage is gained. The backward tilt of the head then produces a passage through the pharynx two or three times wider than when the mouth is left open (Ruben, Bentzen and Saev, 1960;Morikawa, Safar and De Carlo, 1961). Furthermore, when studying the decreasing pharyngeal clearance which occurs when starting from the maximum backward tilt and flexing the head more and more, the clearance produced with the mouth closed is seen to be present through a much wider angle than with the mouth open (Ruben, 1961b).…”

“…Two modifications were suggested, namely pushing forward behind both rami of the mandible, or pulling the jaw forward with a finger inserted in the mouth behind the lower front teeth (Safar, Escarraga and Elam, 1958;Safar, 1958). Simple as these manoeuvres may seem to the anaesthetist, it was soon found that they were only mastered with difficulty, if at all, by laymen (Elam et al, 1960). A simplification of the technique for this purpose was sought and resulted in the use of the head-tilt manoeuvre for opening the airways (Ruben, Elam and Ruben, 1959).…”

“…The backward tilt of the head then produces a passage through the pharynx two or three times wider than when the mouth is left open (Ruben, Bentzen and Saev, 1960;Morikawa, Safar and De Carlo, 1961). Furthermore, when studying the decreasing pharyngeal clearance which occurs when starting from the maximum backward tilt and flexing the head more and more, the clearance produced with the mouth closed is seen to be present through a much wider angle than with the mouth open (Ruben, 1961b). In the second case one needs a backward tilt within less than 15 degrees of the maximum possible to maintain an open air passage, but improper technique or tiredness may easily result in a failure to achieve or maintain this degree of tilt.…”

An Anesthesiologist’s Perspective on the History of Basic Airway Management

“…The valve-like action of the soft palate generated expiratory obstruction with the mouth closed. 75 The radiologic study of Ruben et al 76 The single-rescuer manual technique with both hands used to generate ventilation was replaced by the singlerescuer intermittent positive pressure ventilation expired air technique with both hands used to provide airway patency. The U.S. Army and the American Red Cross adopted mouth-to-mouth ventilation for artificial respiration.…”