GB529404A - Improvements in surgical instruments for performing tracheotomic operations - Google Patents

Abstract

529,404. Surgical operating-appliances. ROSNER, I. May 18, 1939, No. 14881. [Class 81 (ii)] A surgical instrument for performing tracheotomy comprises a lance shaped knife and a tracheal cannula which is detachably secured to the shank at the end remote from the blade. The knife has a blade 1 and shank 2, the end 3 thereof remote from the blade being screwthreaded. The pointed end 6 is sharpened to provide two cutting edges 7. The knife is housed in a hollow tubular casing 8 through which the shank 2 extends, the portion 9 being of reduced diameter to form a grip and the flattened extension 10 normally accommodates the blade. A scale 13 along the edge of a slot 11, through which a fiducial mark 12 on the blade is viewed, serves to indicate the extent the blade projects. A beaded edge 14 acts as a check stop to the blade in operation. The opposite end of the casing 8 is enlarged to form a shoulder 15 meeting the end of a boss 16 formed on a nut 17 which is carried on the threaded end 3 of the shank 2 ; the boss 16 is held by a set screw 19 engaging the groove 18. The blade 1 is projected from or drawn into the casing by rotating the nut 17. The obturator 4 has one end attached to the shank 2 by means of an internally threaded boss 20. The tracheal cannula 5 slides snugly on the obturator 4. The cannula has attached at one end, a radial flange 21 having a pair of radial arms 22 which engage beneath the bridge pieces 23 provided on a shield 24 loosely fitted on the cannula, the shield thus having a limited movement about the cannula. In operation, having made an incision with the blade 1, the cannula 5 obturated by the obturator 4 is inserted in the incision. The obturator is then withdrawn, leaving the cannula held in position by the shield 24.