A text-book of the diseases of the ear for students and practitioners / by Adam Politzer ; tr. at the personal request of the author and ed. by Milton J. Ballin and Clarence L. Heller.

  • Politzer, Adam, 1835-1920.
Date:
1903
Catalogue details

Licence: Public Domain Mark

Credit: A text-book of the diseases of the ear for students and practitioners / by Adam Politzer ; tr. at the personal request of the author and ed. by Milton J. Ballin and Clarence L. Heller. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    fingers are applied around the neck and the bag compressed at its base with the thumb. Hartmann obtained a pressure of 288 mm. Hg by the former method, and only 260 mm. Hg by the latter. If we hear the air entering freely into the middle ear during compression of the bag, the subsequent inflations should be rapidly and powerfully repeated five to six times. The thera- peutic value of the air - douche depends principally on this mode of application. After each compression, the bag should be gently removed from the catheter, to allow it to become refilled with air. Air-bags have been constructed with valves, but they become useless, as a rule, in a short time. Perforated bags for the purpose of aspirating air after compression have proved them- selves impracticable, because the orifice soon becomes greatly dilated and thereby remains open. Treadle air-bags and bellows, which were formerly and again recently recom- mended, have not proved themselves beneficial in practice, as even with large bellows an insufficient pressure is produced. Although the ordinary air- bag suffices in the majority of cases, it is occasionally neces- sary, however, where there is a marked resistance in the Eustachian tube, to resort to a force-pump. The force-pump (Fig. 78) invented by the author consists of a globular metal receptacle, 14 cm. in diameter (e), in which the air is condensed by a piston working in a tube (d). This pump differs from its prede- cessors in that the compression of the air to the necessary degree may be accomplished in a very short time and with only one hand, and that the strength of the escaping current can be precisely .regulated. A strong double acting valve renders it possible, by a rapid upward and downward motion of the piston, to increase the pressure to two-fifths atmosphere in the space of fifteen seconds. The lever-valve (b), attached to the escape-pipe, offers a considerable advantage, as we are able to regulate the strength of the current by changing the position of the lever from the vertical. If we wish to employ a strong but short current, the air can be instantaneously interrupted by a rapid backward and forward movement of the lever. The rubber tube (c), connected with the escape-pipe, is furnished with a conical nozzle (a), which is inserted into the free extremity of the catheter. To determine the pressure of air in the pump, it is supplied with a mercury or spring manometer, which is attached to the escape-pipe behind the valve. In force-numps not provided with a manometer, the pressure may be measured 7 Fig. 78.—Force-pump.