Splash back reduction drip chamber

• US 4,673,397 A
• Filed: 10/29/1986
• Issued: 06/16/1987
• Est. Priority Date: 08/02/1985
• Status: Expired due to Term

• Current Assignee: Baxter Travenol Laboratories Incorporated (Baxter International Inc.)
• Original Assignee: Baxter Travenol Laboratories Incorporated (Baxter International Inc.)
• Inventors: Rollins, Richard, Lynn, Kenneth M.
• Primary Examiner(s): Pellegrino, Stephen C.
• Application Number:
  US06/926,802
• Time in Patent Office: 230 Days
• Field of Search: 604/251-256
• US Class Current: 604/251
• CPC Class Codes: A61M 5/1411 Drip chambers A61M5/162, A61M5/1689, A61M5/40 take precedence

Abstract

A medical fluid administration set and a drip chamber (10) for use on the administration set are disclosed. The drip chamber (10) may be used with conventionally available drop counters whereby fluid flow can be monitored. The drip chamber (10) is intended for incorporation into a medical fluid administration set. At least a portion of the inside surface of the drip chamber (10) has a matte or satin finish (20) as distinguished from a glossy finish. The matte finish (20) alters the surface characteristics between solution residing in the drip chamber (10) and the drip chamber (10) itself, thereby preventing substantial upward splash back or bounce back of liquid drops impacting the surface of the fluid in the drip chamber (10) which splash back or bounce back can result in erroneous flow rate indications.

Claims

1. A drip chamber defining a flexible plastic chamber having an interior surface, an inlet for communicating with drop former, and an outlet, the improvement comprising:

splash back reduction means for reducing splash back of droplets in said chamber, said means including an irregular finish on at least a portion of said interior surface substantially adjacent an anticipated liquid surface level in said chamber, said irregular finish having peaks and valleys ranging from about 140 to 240 microns width, the heights from peaks to valleys ranging from about 140 to 240 microns.

2. The drip chamber of claim 1 wherein portions of said interior surface have substantially circumferential bands of matter irregular finish above and below said anticipated liquid surface level.

3. The drip chamber of claim 2 wherein said drip chamber is made from a polyvinyl chloride material.

4. The drip chamber of claim 2 wherein said chamber has a length of about 1.75 inches to 3.5 inches, an inside diameter at its inlet of about 0.55 inch to 0.65 inch, and an inside diameter at said outlet of about 0.070 inch to 0.090 inch;

and said chamber being formed of a polyvinyl chloride thermoplastic material;

said polyvinyl chloride thermoplastic material having a thickness of about 0.03 inch to 0.08 inch.

5. An administration tubing set for delivering medical fluids to a patient, said set having conduit means to maintain components in flow communication and arranged along the conduit means in the following order:

spike means for accessing a container, a drip chamber having an interior surface, the administration set terminating in connector means for connecting to patient access devices, the improvement comprising;

splash back reduction means for reducing splash back of droplets in said chamber, said means including an irregular finish on at least a portion of said interior surface adjacent an anticipated liquid surface level in said chamber said irregular finish having peaks and valleys ranging from about 140 to 240 microns width, the heights from peaks to valleys ranging from about 140 to 240 microns.

6. The administration tubing set of claim 5 wherein at least a portion of the bottom half of the interior surface of said drip chamber has a substantially circumferential band of irregular finish thereon.

7. The administration tubing set of claim 5 wherein portions of the interior surface of said drip chamber have substantially circumferential bands of irregular finish above and below said anticipated liquid surface level.

8. The administration tubing set of claim 5 wherein said drip chamber is made from a polyvinyl chloride material.

9. A method for improving the accuracy of a drop counting device, said drop counting device being used to count drops of a liquid as the drops fall into a chamber, said chamber having a liquid in the bottom of the chamber, said method comprising the steps of:

dropping liquid drops into said chamber, and reducing splash back of drops impacting the liquid in the bottom of the chamber, wherein said splash back reduction step includes providing at least a portion of the inside surface of the chamber with an irregular finish, said portion being adjacent an anticipated surface level of the liquid chamber, said portion having peaks and valleys ranging from about 140 to 240 microns, the height from peaks to valleys ranging from about 140 to 240 microns, said irregular finish being adjacent an expected liquid surface level.

10. A drip chamber defining a flexible plastic chamber, an inlet for communicating with a drop former, and an outlet, the improvement comprising:

said drip chamber with at least a portion of its interior surface having a substantially circumferential band of irregular finish thereon, said irregular finish including peaks and valleys on the order of about 170 to 240 microns width, the heights from the peaks to the valleys being on the order of about 170 to 240 microns, said circumferential band being adjacent the anticipated liquid surface level.

11. The drip chamber of claim 10 wherein at least a portion of the bottom half of its interior surface has said circumferential band of irregular finish thereon.

12. The drip chamber of claim 10 wherein portions of its interior surface have substantially circumferential bands of irregular finish above and below said anticipated liquid surface level.

13. The drip chamber of claim 10 wherein said drip chamber is made from a polyvinyl chloride material.

14. The drip chamber of claim 10 wherein said chamber has a length of about 1.75 inches to 3.5 inches, an inside diameter at its inlet of about 0.55 inch to 0.65 inch, and an inside diameter at said outlet of about 0.070 to 0.090 inch;

and said chamber being formed of a polyvinyl chloride thermoplastic material;

said polyvinyl chloride thermoplastic material having a thickness of about 0.03 inch to 0.08 inch.

15. An administration tubing set for delivering medical fluids to a patient, said set having conduit means to maintain components in flow communication and arranged along the conduit means in the following order:

spike means for accessing a container, a drip chamber, the adminstration set terminating in connector means for connecting to patient access devices, the improvement comprising;

said drip chamber with at least a portion of its interior surface having a substantially circumferential band of irregular finish thereon, said irregular finish including peaks and valley on the order of about 140 to 230 microns width, the heights from the peaks to the valleys being on the order of about 140 to 230 microns, said circumferential band being adjacent the anticipated liquid surface level.

16. The administration tubing set of claim 15 having said drip chamber wherein at least a portion of the bottom half of the interior surface of said drip chamber has a circumferential band of irregular finish thereon.