Adaptor assembly for airway tube

Claim 2

An adaptor assembly for sampling gas in an airway tube attached to a patient, said adaptor assembly comprising, a tubular section adapted for securing in series with the airway tube, said tubular section having an opening between the opposite ends thereof, sample tube connecting means for securing a sample tube in communication with the interior of said tubular section intermediate the ends thereof, said connecting means being secured to said tubular section at said opening therein and including a filter probe extending a predetermined distance across the interior of said tubular section to provide filtered communication between the interior of said tubular section and said sample tube, said filter probe having a filter at the end thereof inside said tubular section, said filter having a first filter surface area exposed to the interior of said tubular section and a second surface area opposite said first surface area, means defining a void volume contiguous with said second surface area, said first surface area having a ratio of surface area to void volume in excess of 10 to 1 square centimeters to cubic centimeters.

Claim 3

An adaptor assembly according to claim 1 wherein said void volume defining means include means for supporting said filter by engaging said second surface area.

Claim 4

An adaptor assembly according to claim 2 wherein said supporting means include a plurality of substantially parallel ribs.

Claim 5

An adaptor assembly according to claim 1 wherein said filter probe extends a substantial distance across the interior of said tubular section.

Claim 6

An adaptor assembly according to claim 1 wherein said filter is substantially planar and has an outer surface exposed to the interior of said tubular section and an inner surface, and wherein said filter probe includes a plurality of channels immediately adjacent said inner surface of said filter and providing passages from said filter to the sample tube.

Claim 7

An adaptor assembly according to claim 1 wherein said filter probe is a size such as to obstruct less than about 40% of the cross-sectional area of the interior of said tubular section.

Claim 8

An adaptor assembly for sampling gas in an airway tube attached to a patient, said adaptor assembly comprising, a tubular section adapted for securing in series with an airway tube, said tubular section comprising a substantially cylindrical wall having a longitudinal axis and an opening in said wall between the opposite ends thereof, a sample tube mounting subassembly having attachment means for securing a sample tube in communication with said tubular section intermediate the ends thereof, said subassembly being mounted to said tubular section at said opening in said wall thereof and including a filter probe extending transversely of said longitudinal axis of said cylindrical wall a predetermined distance across the interior of said tubular section to provide filtered communication between the interior of said tubular section and said sample tube, said filter probe having a filter at the end thereof inside said tubular section with a first filter surface area exposed to the interior of said tubular section, said filter probe having a recess therein coextensive with said filter, said recess having means therein comprising a plurality of ribs for supporting said filter spaced from the bottom of said recess to leave a void volume therein, said filter probe further having a passage therein communicating between said void volume in said recess and said sample tube, said first and opposite surfaces being substantially equal in area, said void volume in said recess combined with the void volume in said passage being selected to have a ratio of filter first surface area to void volume in excess of about 10 to 1 square centimeters to cubic centimeters.

Claim 9

An adaptor assembly for sampling gas in an airway tube attached to a patient, said adaptor assembly comprising, a tubular section adapted for securing in series with an airway tube, said tubular section comprising a substantially cylindrical wall having a longitudinal axis and an opening in said wall between the opposite ends thereof, a sample tube mounting subassembly having attachment means for securing a sample tube in communication with said tubular section intermediate the ends thereof, said subassembly being mounted to said tubular section at said opening in said wall thereof and including a filter probe extending transversely of said longitudinal axis of said cylindrical wall a predetermined distance across the interior of said tubular section to provide filtered communication between the interior of said tubular section and said sample tube, said filter probe having a filter at the end thereof inside said tubular section with a first filter surface area exposed to the interior of said tubular section, said filter probe having a recess therein coextensive with said filter, said recess having means therein comprising a plurality of ribs for supporting said filter spaced from the bottom of said recess to leave a void volume therein, said filter probe further having a passage therein communicating between said void volume in said recess and said sample tube, said first and opposite surfaces being substantially equal in area, said void volume in said recess combined with the void volume in said passage being selected to have a ratio of filter first surface area to void volume in excess of about 10 to 1 square centimeters to cubic centimeters.

Claim 10

An adaptor assembly for sampling gas in an airway tube attached to a patient, said adaptor assembly comprising, a tubular section adapted for being secured in series with the airway tube, said tubular section having an opening between the opposite ends thereof, sample tube connecting means for securing a sample tube in communication with the interior of said tubular section intermediate the ends thereof, said connecting means being secured to said tubular section at an opening therein and including a filter probe positioned to provide filtered communication between the interior of said tubular section and said sample tube, said filter probe having a filter positioned to communicate with the inside of said tubular section, said filter comprising first and second substantially parallel planar surfaces and a plurality of filter pores connecting said first and second surfaces, said first surface being exposed to the interior of said tubular section, said filter probe further comprising a recess contiguous with said second surface of said filter and a conduit for connecting said recess to said sample tube, said recess having a plurality of ribs therein in contact with said second filter surface for supporting said filter, said ribs being oriented and spaced from each other to define a plurality of passageways in communication between said second surface and said conduit, said passageways and the said filter pores defining a void volume, the ratio of the surface area of said first filter surface to said void volume being greater than 10 to 1 square centimeters to cubic centimeters.

Claim 11

An adaptor assembly for sampling gas in an airway tube attached to a patient, said adaptor assembly comprising, a tubular section adapted for being secured in series with the airway tube, said tubular section having an opening between the opposite ends thereof, sample tube connecting means for securing a sample tube in communication with the interior of said tubular section intermediate the ends thereof, said connecting means being secured to said tubular section at an opening therein and including a filter probe positioned to provide filtered communication between the interior of said tubular section and said sample tube, said filter probe having a filter positioned to communicate with the inside of said tubular section, said filter comprising first and second substantially parallel planar surfaces and a plurality of filter pores connecting said first and second surfaces, said first surface being exposed to the interior of said tubular section, said filter probe further comprising a recess contiguous with said second surface of said filter and a conduit for connecting said recess to said sample tube, said recess having a plurality of ribs therein in contact with said second filter surface for supporting said filter, said ribs being oriented and spaced from each other to define a plurality of passageways in communication between said second surface and said conduit, said passageways and the said filter pores defining a void volume, the ratio of the surface area of said first filter surface to said void volume being greater than 10 to 1 square centimeters to cubic centimeters.