Method and apparatus for the reuse of anesthetic gases in inhalation anesthesia with specific size and position of CO.sub.2 absorber

An apparatus for re-using anesthetic gases in inhalation anesthesia comprising:

• means adapted for connection to a patient via a connector for ventilating the patient with an anesthetic gas and respiration gas, the patient thereby producing exhaled gas, in an exhalation line, containing anesthetic gas which was not absorbed by said patient and carbon dioxide, and a remainder of exhaled gas;
• adsorption filter means communicating with said exhalation line for adsorbing said anesthetic gas in said exhaled gas which was not absorbed by the patient during respiration, and thereby simultaneously unavoidably adsorbing a small amount of said carbon dioxide in said exhaled gas, and for permitting said remainder of exhaled gas to pass through said adsorption filter means;
• means for evacuating said remainder of exhaled gas;
• said means for ventilating, in a subsequent inhalation phase, directing fresh respiration gas through said adsorption filter means so that the anesthetic gas and said small amount of carbon dioxide previously adsorbed by said adsorption filter means are desorbed into said fresh respiration gas;
• a carbon dioxide absorber disposed in an inhalation line, separate from said exhalation line, between said adsorption filter and said connector;
• means for directing said fresh respiration gas which has passed through said adsorption filter means through said carbon dioxide absorber for absorbing said small amount of carbon dioxide;
• a bypass line bypassing said adsorption filter means and said carbon dioxide absorber;
• means for directing at least one of fresh respiration and fresh anesthetic gas from said means for ventilating through said bypass line;
• means for combining the gas directed through said bypass line with the fresh gas which has passed through said adsorption filter means and said carbon dioxide absorber in a desired gas concentration for forming a mixture and for supplying said mixture to said connector;
• and
• an inhalation branch and an exhalation branch communicating with said connector and a main conduit connected to an input of said means for ventilating, said adsorption filter means and said carbon dioxide absorber being disposed in parallel in a single container, said container having a first channel between said adsorption filter means and said carbon dioxide absorber, a second channel formed between said adsorption filter and a first inside wall of said container, and a third channel formed between said carbon dioxide absorber and a second inside wall of said container, said first channel being connected to said exhalation branch, said second channel being connected to said main conduit at a side of said adsorption filter means facing away from said connector, and said third channel being connected to said inhalation branch.

An apparatus for re-using anesthetic gases in inhalation anesthesia comprising:

• means adopted for connection to a patient via a connector for ventilating the patient with an anesthetic gas and respiration gas, the patient thereby producing exhaled gas, in an exhalation line, containing anesthetic gas which was not absorbed by the patient and carbon dioxide, and a remainder of exhaled gas;
• an adsorption filter means communicating with said exhalation line for directing the exhaled gas through said adsorption filter means for adsorbing said anesthetic gas in said exhaled gas which was not absorbed during respiration, and thereby simultaneously unavoidably adsorbing a small amount of said carbon dioxide and for permitting said remainder of exhaled gas to pass through said adsorption filter means;
• means for evacuating said remainder of exhaled gas;
• said means for ventilating, in a subsequent inhalation phase, directing fresh respiration gas through said adsorption filter means so that the anesthetic gas and said small amount of carbon dioxide previously adsorbed by said adsorption filter means are desorbed into said fresh respiration gas;
• an inhalation line, separate from said exhalation line;
• carbon dioxide absorber means, disposed in said inhalation line between said adsorption filter means and said connector, for minimizing said exhalation resistance by its placement in said inhalation line and by having a carbon dioxide absorption capacity matched to said small amount of carbon dioxide for adsorbing no more than said small amount of carbon dioxide;
• means for directing said fresh respiration gas which has passed through said adsorption filter means through said carbon dioxide absorber for absorbing said small amount of carbon dioxide;
• a bypass line bypassing said adsorption filter and said carbon dioxide absorber;
• means for directing at least one of fresh respiration and fresh anesthetic gas from said means for ventilating through said bypass line;
• and
• means for combining the gas directed through said bypass line with the fresh gas which has passed through said adsorption filter means and said carbon dioxide absorber in a desired gas concentration for forming a mixture and for supplying said mixture to said connector.