Anesthetic dispenser with mixing unit and anesthetic tank and process using anesthetic dispenser

An arrangement comprising:

• an anesthetic dispenser comprising:
• a mixing unit configured to generate a gas mixture comprising at least one anesthetic and a carrier gas;
• an anesthetic tank with a refill opening;
• a closure for the refill opening, the closure being configured to move from a closed position via an intermediate position to an open position and being configured to close the refill opening in the closed position and in the intermediate position and release the refill opening in the open position;
• an anesthetic line leading from the anesthetic tank to the mixing unit;
• a controllable pressure increasing unit configured to increase pressure in the anesthetic tank or to effect such a pressure increase;
• a controllable pressure reduction unit configured to reduce pressure in the anesthetic tank or to effect such a pressure reduction;
• a pressure sensor configured to measure pressure in the anesthetic tank;
• a position sensor configured to detect an event that the closure has been moved out of a closed position, wherein the anesthetic dispenser is configured such that a transition time period elapses when the closure is moved from the closed position to the intermediate position;
• and
• a signal processing control unit configured:
• to receive measured values from the pressure sensor and the position sensor;
• to trigger an increase in pressure in the anesthetic tank by controlling the pressure increasing unit;
• to trigger a reduction of the pressure in the anesthetic tank by controlling the pressure reduction unit;
• wherein the anesthetic dispenser is selectively operable in an operating mode or in a refill mode, wherein in the operating mode the closure is in the closed position and the control unit maintains an actual pressure in the anesthetic tank at a specified operating pressure or above the specified operating pressure, and in the refill mode the closure is in the open position and the refill opening enables refilling of anesthetic into the anesthetic tank;
• and
• wherein the control unit is arranged to trigger a reduction of the pressure in the anesthetic tank by controlling the pressure reduction unit such that the actual pressure in the anesthetic tank falls below the operating pressure and remains above an ambient pressure at least in the transition time period,
• wherein the control unit is arranged to trigger the pressure reduction after detection of the event that the closure has been moved out of the closed position;
• and
• a carrier gas supply unit in fluid communication with the anesthetic dispenser for supplying the carrier gas, the carrier gas supply unit comprising a carrier gas mixer.

A system for anesthetizing a patient, the system comprising:

• a ventilator;
• and
• an anesthetic dispenser in fluid communication with the ventilator, wherein the ventilator is configured to anesthetize the patient using a gas mixture generated by the anesthetic dispenser, the anesthetic dispenser comprising:
• a mixing unit configured to generate a gas mixture comprising at least one anesthetic and a carrier gas;
• an anesthetic tank with a refill opening;
• a closure for the refill opening, the closure being configured to move from a closed position via an intermediate position to an open position and being configured to close the refill opening in the closed position and in the intermediate position and release the refill opening in the open position;
• an anesthetic line leading from the anesthetic tank to the mixing unit;
• a controllable pressure increasing unit configured to increase pressure in the anesthetic tank or to effect such a pressure increase;
• a controllable pressure reduction unit configured to reduce pressure in the anesthetic tank or to effect such a pressure reduction;
• a pressure sensor configured to measure pressure in the anesthetic tank;
• a position sensor configured to detect an event that the closure has been moved out of a closed position, wherein the anesthetic dispenser is configured such that a transition time period elapses when the closure is moved from the closed position to the intermediate position;
• and
• a signal processing control unit configured:
• to receive measured values from the pressure sensor and the position sensor;
• to trigger an increase in pressure in the anesthetic tank by controlling the pressure increasing unit;
• to trigger a reduction of the pressure in the anesthetic tank by controlling the pressure reduction unit;
• wherein the anesthetic dispenser is selectively operable in an operating mode or in a refill mode, wherein in the operating mode the closure is in the closed position and the control unit maintains an actual pressure in the anesthetic tank at a specified operating pressure or above the specified operating pressure, and in the refill mode the closure is in the open position and the refill opening enables refilling of anesthetic into the anesthetic tank;
• and
• wherein the control unit is arranged to trigger a reduction of the pressure in the anesthetic tank by controlling the pressure reduction unit such that the actual pressure in the anesthetic tank falls below the operating pressure and remains above an ambient pressure at least in the transition time period,
• wherein the control unit is arranged to trigger the pressure reduction after detection of the event that the closure has been moved out of the closed position.

A process for generating a gas mixture comprising at least an anesthetic and a carrier gas using an anesthetic dispenser comprising a mixing unit, an anesthetic tank with a refill opening, a closure for the refill opening, an anesthetic line guiding from the anesthetic tank to the mixing unit, a controllable pressure increasing unit, a controllable pressure reduction unit, a pressure sensor and a position sensor, the process comprising the step of

• measuring an actual pressure in the anesthetic tank with the pressure sensor;
• operating the anesthetic dispenser in an operating mode comprising the steps of:
• providing the closure in a closed position, in which the closure closes the refill opening;
• bringing the actual pressure in the anesthetic tank to a specified operating pressure and/or maintain the pressure equal to or above a specified operating pressure using the pressure increasing unit;
• conveying at least one anesthetic from the anesthetic tank through the anesthetic line to the mixing unit;
• and
• generating in the mixing unit a gas mixture comprising anesthetic conveyed to the mixing unit and a carrier gas;
• and
• refilling the anesthetic tank comprising:
• moving the closure from the closed position to an open position via an intermediate position, wherein the closure also closes the refill opening in the intermediate position and releases the refill opening in the open position;
• w42herein the closure in the open position allows refilling of anesthetic into the anesthetic tank;
• wherein a transition time period occurs during a movement of the closure from the closed position to the intermediate position;
• detecting with the position sensor the event that the closure has been moved out of the closed position;
• in response to the detection of the event that the closure has been moved out of the closed position lowering by using the pressure reduction unit the actual pressure in the anesthetic tank such that the actual pressure falls below the operating pressure and remains at least in the transition period, above an ambient pressure.