Laryngoscope is a medical instrument use to obtain a view of the vocal folds and the glottis, which is the space between the cords. The first laryngoscope was invented in 1854 by Manuel Patricio Rodriguez Garcia. Modern day laryngoscope systems initially began in early 1940s by Foregger, Co. USA.
A Laryngoscope basically has two components - an interchangeable hook on blade and a battery handle. The Blade is hooked on to the hinge pin, and then rotated to a 90° position where the blade heel contacts the handle top - turning the lamp ON.
CONVENTIONAL LIGHT LARYNGOSCOPES: Blades have a lamp near the distal end and have an electrical connection to illuminate the lamp, powered by batteries in handle.
FIBRE OPTIC LIGHT LARYNGOSCOPES: Advancement in newer lighting technologies eliminated electric wires, lamps & contacts from blade thus producing a very dependable, cold and brighter illumination. Our F/O handles are fitted with latest LED / XENON lamps that produce excellent light, which follows a quartz glass fiber optic bundle or plastic bundle along the blade to illuminate a patient's oral cavity.
In an attempt to visualize the Larynx and facilitate insertion of Endotracheal Tube, literally hundreds of blade profiles and sizes have been made or suggested. However all blades fall into modification of Two general shapes:
CURVED BLADES: The most common and popular blade. Suggested by Sir Robert Macintosh, MD in 1941, this curved blade is design such that its tip is advanced to the base of patient's epiglottis, then, by lifting slightly, the vocal cords can be visualized to allowing for endotracheal tube insertion.
STRAIGHT BLADES: The other most common blade was described by William Miller, MD. In this design using a straight blade, the tip is advanced just past the patient's epiglottis. The blade is then raised lifting the epiglottis thus exposing the vocal cords allowing the Endotracheal tube to be inserted along the flange into larynx.