Catheter device for use in detecting gas in body fluids and tissue

• US 3,893,448 A
• Filed: 11/26/1973
• Issued: 07/08/1975
• Est. Priority Date: 11/26/1973
• Status: Expired due to Term

• Current Assignee: John W. Brantigan
• Original Assignee: John W. Brantigan
• Inventors: Brantigan, John W.
• Primary Examiner(s): Howell, Kyle L.
• Application Number:
  US05/419,109
• Time in Patent Office: 589 Days
• Field of Search: 128/2E,2G,2L,2.1E,2.5R,348,214
• US Class Current: 600/364
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61M 25/0069 Tip not integral with tube

Abstract

A blood or tissue gas diffusion catheter device comprising a catheter having a lumen therethrough and provided with a solid distal end portion enclosed within a membrane permeable to gases that might be found in blood or tissue, said distal end portion being shaped to provide a helical path over the outside thereof communicating with the lumen of the catheter, and said end portion being shaped to permit direct insertion of the distal end portion into the body of a patient without the use of a cannulated needle or an otherwise preformed entry.

Claims

1. A catheter device for use with analyzing apparatus to obtain samples of gases from the blood or tissue of a patient, said device including a cannula carrying a distal end portion covered by a tubular membrane permeable to body gases and insertable into a blood vessel or tissue of a patient, wherein the improvement comprises:

said distal end portion being solid throughout its length, and said solid end portion being shaped to provide a path for gases between its external surface and said membrane covering it leading to the lumen of said cannula.

2. The catheter device in claim 1, wherein said solid end portion is grooved externally to provide the path for gases.

3. The catheter device of claim 1, wherein said solid end portion is provided with a helical groove in its external surface to provide the path for gases.

4. The catheter device of claim 1, wherein said solid end portion contains a plurality of helical grooves in its external surface to provide the path for gases.

5. The catheter device of claim 1, wherein said distal end portion comprises a solid bar of material polygonal in cross section and of less size than the inside diameter of said tubular membrane, said bar being twisted to contact said membrane at spaced intervals.

6. The catheter of claim 1, wherein said solid distal end portion terminates in an end of sufficient size to close the end of said tubular membranE, and which end slopes at its distal face to provide a sharp point, whereby said catheter device may itself be positioned in the body of a patient without aid from other entry establishing means.

7. The catheter device of claim 1, wherein said distal end portion has a solid portion extending throughout the length of the distal end portion of an area in the range of 0.54 to 0.833 of the cross sectional area of the inside of said tubular membrane.

8. The catheter device of claim 1, which has an overall outside diameter less than 0.035 inch.

9. The catheter device of claim 5, including an end member attached to said solid twisted bar of a size to close the end of said tubular membrane and having a sloping distal face terminating in a sharp point.

10. The catheter device of claim 6, including a monofilament covering the sloping face of said end but made of sufficiently thin and strong material as not to interfere with the insertion of the device into the body of a patient.