Pressure indicators for inflatable cuff-type catheters

Claim 1

An inflatable cuff-type catheter for insertion into a body passage comprising in combination a flexible tube having distal and proximal ends, at least one gas inflatable cuff encircling the flexible tube near the distal end and having opposite ends sealed thereto; a branched tube connected at an inner end to the interior of the cuff; and an inflation means and a pressure indicator means connected in series to the cuff through the outer end of the branch tube for access outside the body passage, the indicator means comprising an expandable chamber encircling the branched tube with opposite ends sealed thereto; the branched tube having radial openings communicating with the interior of the chamber for the passage of the cuff inflating gas into the chamber, the expandable chamber having at one end a cone-shaped shell encircling the chamber, the apex end of the shell encircling and adhered to the branched tube, the chamber having indicia on the surface of the shell end, wherein the chamber upon expansion is adapted to progessively expose the indicia and by a pre-determined progression of the indicia the gass pressure within the inflatable cuff.