Multi-lumen epidural catheter

• US 4,737,146 A
• Filed: 04/20/1987
• Issued: 04/12/1988
• Est. Priority Date: 12/25/1979
• Status: Expired due to Fees

• Current Assignee: Osamu Nagano, Yoshikiyo Amaki
• Original Assignee: Osamu Nagano, Yoshikiyo Amaki
• Inventors: Nagano, Osamu, Amaki, Yoshikiyo
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US07/042,615
• Time in Patent Office: 358 Days
• Field of Search: 604/43-45, 604/51-53, 604/158-170, 604/272-275, 604/280-284
• US Class Current: 604/512
• CPC Class Codes: A61B 17/3401 Puncturing needles for the peridural or subarachnoid space or the plexus, e.g. for anaesthesia local anaesthesia A61M19/00
• CPC Class Codes: A61M 25/06 Body-piercing guide needles or the like

Abstract

A multi-lumen epidural catheter includes a flexible inner tube 10 having a tip opening 12 and a surrounding flexible outer tube 11 having a pair of side openings 13 spaced upstream from the tip. An anesthetic solution may be injected through the separate flow and discharge paths defined by this structure to deaden a more elongate zone of a patient in a precisely controlled manner.

Claims

1. A method for continuous epidural anesthesia, comprising the steps of:

(a) inserting a rigid, hollow epidural needle (1) successively through a patient'"'"'s skin (2), subcutaneous tissue (3), interspinous ligament (5) and ligamentum flavum (6) until the tip of the needle reaches an epidural space (7),

(b) introducing a double-lumen epidural catheter (9) through the needle, out through a lateral opening in the tip of the needle, and into the epidural space to a length of about 5 cm,

(c) said epidural catheter comprising;

(1) at least one flexible inner tube having a tip and a rear portion forming a first path for an anesthetic solution, and a flexible outer tube having a tip and a rear portion forming a second path for an anesthetic solution between said inner and outer tubes,

(2) said inner tube having an opening at the tip thereof,

(3) said outer tube having at least one pair of side openings at portions spaced from the tip of the outer tube a distance not exceeding the length of an epidural space, and

(4) said inner tube being separated from said outer tube at the rear portions thereof so that openings for the inflow of an anesthetic solution into each of said tubes are provided at the rear portions of said inner and outer tubes, respectively, said inner tube having an inner diameter of about 0.2 to about 0.6 mm and an outer diameter of about 0.4 to about 0.8 mm, and said outer tube having an inner diameter of about 0.6 to about 1.0 mm and an outer diameter of about 0.8 to about 1.2 mm, and

(d) introducing an anesthetic solution through the rear portions of the inner and outer tubes, through the first and second paths defined thereby, and into the epidural space through the tip opening (12) of the inner tube and the side openings (13) of the outer tube such that contiguous droplets of anesthetic solution form around said tip opening and side openings, the total volume of anesthetic solution necessary to anesthetize a given length of epidural space being less than that required using a catheter having a single fluid outlet.