Scavenger system

• US 4,527,558 A
• Filed: 06/24/1983
• Issued: 07/09/1985
• Est. Priority Date: 06/24/1983
• Status: Expired due to Fees

• Current Assignee: Matrix Medical LLC
• Original Assignee: BOC Group Pty Limited (Linde Plc)
• Inventors: Hoenig, Richard
• Primary Examiner(s): Recla, Henry J.
• Application Number:
  US06/507,396
• Time in Patent Office: 746 Days
• Field of Search: 128/910, 128/205.12, 128/201.27, 128/201.28, 128/205.19, 128/203.28, 128/205.17, 128/204.18, 128/205.24, 128/204.26, 137/887, 138/30
• US Class Current: 128/205.24
• CPC Class Codes: A61M 16/009 Removing used or expired gases or anaesthetic vapours filtering, sterilising or disinfecting the exhaust air in drainage systems A61M1/784; bacterial filters in the expiratory path A61M16/1065
• CPC Class Codes: A61M 2202/0014 removed from the body
• CPC Class Codes: A61M 2202/0225 Carbon oxides, e.g. Carbon dioxide
• CPC Class Codes: A61M 2209/084 Supporting bases, stands for equipment
• CPC Class Codes: Y10S 128/91 Anesthesia gas scavenging system

Abstract

A gas scavenger system is disclosed for use particularly with anesthetic administering equipment utilizing a demand valve for providing anesthetic gas to the patient. The gas scavenger system includes a collection manifold that collects the waste gases as they leave the normal exhaust ports of the demand valve. A flexible tubing means then carries those collected gases to a surge chamber prior to eventual discharge into a vacuum system. The surge chamber provides an interface between the vacuum system and the collection manifold and is connected to the vacuum system through a predetermined sized orifice which limits the flow to the vacuum system to a maximum known flow. The surge chamber normally allows continuous flow through the orifice to the vacuum system but is sized to accumulate an excess of flow from the collection manifold under abnormal conditions such as is occasioned when a patient coughs to allow time to remove the gases through the orifice and thus to prevent leakage to atmosphere. The surge chamber itself is directly connected to ambient through a known, fixed resistance of hydrophobic material such that an excess in pressure in the surge chamber above a maximum amount that determined by the known, fixed resistance is bled to atmosphere. Thus, in the event of an occlusion in the vacuum line, the patient is always assured a path for exhalation. Also, in the event the vacuum system draws gas at a faster flow rate than that of waste gases entering the surge chamber from the collection manifold, gas will be drawn from the ambient through the known, fixed resistance.

Claims

1. A gas scavenger system for conveying waste exhalation gas to a vacuum system from an anesthetic apparatus having a demand valve for administering an anesthetic gas to a patient and having exhaust ports for normally passing the waste exhalation gas from the patient to atmosphere, said gas scavenger system comprising collection manifold means receiving the waste exhalation gas from the exhaust ports, surge chamber means connected to said collection manifold means and adapted to receive the waste exhalation gas therefrom, said surge chamber means having an outlet connectable to the vacuum system and having a valve means limiting the flow of gas from said surge chamber means to the vacuum system, said surge chamber means containing a predetermined volume to receive normal excess flows occasioned by exhalation from the patient, fixed resistance means forming a flow path between said surge chamber means and the surrounding atmosphere, said fixed resistance means comprising an elongated tube extending essentially within the interior of said surge chamber means, said tube having one end thereof open within said surge chamber means and having the other end open to surrounding atmosphere external of said surge chamber means, said tube containing a substantially hydrophobic substance having a known flow resistance and which allows the flow of gas through said tube to the atmosphere when the pressure in said surge chamber means exceeds a predetermined maximum value and allows the flow of gas through said tube to said surge chamber means from the atmosphere when the vacuum in said surge chamber means exceeds a predetermined value.

2. A gas scavenger system as in claim 1, wherein said substance is polyurethane foam.

3. A gas scavenger system as in claim 1, wherein said surge chamber means further has a relief valve in its lower portion to relieve build up of liquid in said surge chamber means when said liquid reaches a predetermined head.

4. A gas scavenger system as in claim 1 wherein said valve means is a multi-position valve adapted to vary the maximum flow of gas from said surge chamber means.

6. An interface surge chamber as in claim 1, wherein said substance is polyurethane foam.

7. Gas scavenger system as in claim 1, wherein said interface surge chamber further has a relief valve in its lower portion to relieve build up of liquid in said interface surge chamber when said liquid reaches a predetermined head.

5. An interface surge chamber for receiving gas of a varying flow to direct that gas to a constant vacuum source, said interface surge chamber comprising an inlet for receiving gas from said varying flow source and an outlet connectable to the vacuum system, a valve means limiting the flow of gas from said interface surge chamber to the vacuum system, said interface surge chamber having a predetermined volume to receive and contain excess flows from the varying flow source, fixed resistance means forming a flow path between said interface surge chamber and the surrounding atmosphere, said fixed resistance comprising an elongated tube extending essentially within the interior of said interface surge chamber, said tube having one end thereof open to atmosphere through said interface surge chamber and the other end within said interface surge chamber, said tube containing a substantially hydrophobic substance of predetermined flow resistance to allow the flow of gas through said tube to the atmosphere when the pressure in said interface surge chamber exceeds a predetermined value and allows flow of gas through said tube to said surge chamber from the atmosphere when the vacuum in said surge chamber exceeds a predetermined value.