Arrangement and process for supplying a patient-side coupling unit with a gas mixture

1 . An arrangement for supplying a patient-side coupling unit with a gas mixture, the gas mixture comprising a first gas component and a second gas component, wherein the patient-side coupling unit is configured to be connected to a patient, the supply arrangement comprising:

a first duct with a supply connection element, the supply connection element is configured to establish a fluid connection with a first source for the first gas component;

a second duct;

a mixing point connected to the first duct and connected to the second duct, wherein the first duct is configured to guide the first gas component from the supply connection element to the mixing point;

an inspiration duct configured to direct a gas mixture formed in the mixing point to the patient-side coupling unit;

a buffer reservoir with a supply chamber, the supply arrangement is configured to establish a fluid connection from a second source for the second gas component to the supply chamber, wherein a supply fluid connection between the supply chamber and the second duct is established or establishable, wherein the second duct is configured to direct the second gas component from the supply chamber to the mixing point; and

a pneumatic control line establishing a control fluid connection between the first duct and the buffer reservoir,

wherein the supply arrangement is configured such that the buffer reservoir, the supply fluid connection, and the control fluid connection together effect a pressure balancing between a pressure in the supply chamber, a pressure in the first duct and a pressure in the second duct,

wherein the buffer reservoir comprises a housing and a flexible fluid-tight separating element inside the housing,

wherein the separating element fluid-tightly divides the interior of the housing into the supply chamber and a control chamber, and the separating element comprises a flexible bag,

wherein the control fluid connection pneumatically connects the control chamber to the first duct and causes a pressure balancing between the control chamber and the first duct,

wherein an interior space is formed between the housing and the bag, the interior space surrounding the bag,

wherein the supply chamber is formed inside the bag and the control chamber is formed in the interior space between the housing and the bag or the control chamber is formed inside the bag and the supply chamber is formed in the interior space between the housing and the bag.

2 . A supply arrangement according to claim 1 wherein

the supply chamber is formed inside the bag; and

both the fluid connection between the supply chamber and the second source and the supply fluid connection are passed through the housing.

3 . A supply arrangement according to claim 1 further comprising a sensor arrangement, wherein:

the sensor arrangement is adapted to measure an indicator for a difference between the pressure in the supply chamber and the pressure in the control chamber; and

the supply arrangement is configured to generate a message when the measured pressure difference is outside a predetermined range.

4 . A supply arrangement according to claim 1 , further comprising:

a third duct; and

a pressure reducer including an upstream pressure inlet and a downstream pressure outlet, wherein:

a fluid connection is established or establishable between the upstream pressure inlet of the pressure reducer and a further source for the second gas component;

the downstream pressure outlet of the pressure reducer is connected to the third duct;

the third duct is configured to direct the second gas component from the downstream pressure outlet to the mixing point or to a further mixing point;

the further mixing point is in fluid communication with the mixing point and/or with the patient-side coupling unit; and

the pressure reducer is configured to provide the second gas component such that a time course of the pressure at the downstream pressure outlet follows a time course of the pressure in the first duct and/or a time course of the pressure in the second duct.

5 . A supply arrangement according to claim 4 , further comprising a further pneumatic control line, wherein:

the pressure reducer comprises a control pressure input; and

the further pneumatic control line establishes a control fluid connection between the first duct and the control pressure input.

6 . A system for supplying a patient-side coupling unit with a gas mixture, the gas mixture comprising a first gas component and a second gas component, the supply system comprising:

a first source configured to provide the first gas component;

a second source configured to provide the second gas component; and

a supply arrangement comprising:

a first duct with a supply connection element, the supply connection element is configured to establish a fluid connection with the first source for the first gas component;

a second duct;

a mixing point connected to the first duct and connected to the second duct, wherein the first duct is configured to guide the first gas component from the supply connection element to the mixing point;

an inspiration duct configured to direct a gas mixture formed in the mixing point to the patient-side coupling unit;

a buffer reservoir with a supply chamber, wherein the supply chamber is configured to establish a fluid connection with the second source for the second gas component and with a supply fluid connection with the second duct, wherein the second duct is configured to direct the second gas component from the supply chamber to the mixing point; and

a pneumatic control line establishing a control fluid connection between the first duct and the buffer reservoir, wherein the supply arrangement is configured such that the buffer reservoir, the supply fluid connection, and the control fluid connection effect a pressure balancing between a pressure in the supply chamber, a pressure in the first duct and a pressure in the second duct,

wherein the buffer reservoir comprises a housing and a flexible fluid-tight separating element inside the housing,

wherein the separating element fluid-tightly divides the interior of the housing into the supply chamber and a control chamber, and the separating element comprises a flexible bag,

wherein the control fluid connection pneumatically connects the control chamber to the first duct and causes a pressure balancing between the control chamber and the first duct

wherein an interior space is formed between the housing and the bag, the interior space surrounding the bag,

wherein the supply chamber is formed inside the bag and the control chamber is formed in the interior space between the housing and the bag or the control chamber is formed inside the bag and the supply chamber is formed in the interior space between the housing and the bag.

7 . A system according to claim 6 , further comprising a further source of the second gas component, wherein:

the supply arrangement further comprises a third duct and a pressure reducer, the pressure reducer including an upstream pressure inlet and a downstream pressure outlet,

a fluid connection is established or establishable between the upstream pressure inlet of the pressure reducer and the further source of the second gas component;

the downstream pressure outlet of the pressure reducer is connected to the third duct;

the third duct is configured to direct the second gas component from the downstream pressure outlet to the mixing point or to a further mixing point;

the further mixing point is in fluid communication with the mixing point and/or with the patient-side coupling unit; and

the pressure reducer is configured to provide the second gas component such that a time course of the pressure at the downstream pressure outlet follows a time course of the pressure in the first duct and/or a time course of the pressure in the second duct.

8 . A system according to claim 7 , wherein

the supply arrangement further comprises a further pneumatic control line;

the pressure reducer comprises a control pressure input; and

the further pneumatic control line establishes a control fluid connection between the first duct and the control pressure input.

9 . A system according to claim 7 , wherein the further source provides the second gas component at a higher pressure than the second source.

10 . A system according to claim 6 , further comprising:

a fluid delivery unit connected to the supply connection element and being part of the first gas source; and

the patient-side coupling unit, wherein the system is configured for artificial ventilation of a patient, wherein

the patient-side coupling unit is configured to be connected to the patient; and

the fluid delivery unit is configured to deliver the gas mixture supplied by the supply arrangement to the patient-side coupling unit.

11 . A system according to claim 6 wherein

the supply chamber is formed inside the bag; and

both the fluid connection between the supply chamber and the second source and the supply fluid connection are passed through the housing.

12 . A system according to claim 6 , further comprising a sensor arrangement, wherein:

the sensor arrangement is adapted to measure an indicator for a difference between the pressure in the supply chamber and the pressure in the control chamber; and

the supply arrangement is arranged to generate a message when the measured pressure difference is outside a predetermined range.

13 . A process for supplying a patient-side coupling unit with a gas mixture comprising a first gas component and a second gas component, wherein the patient-side coupling unit is connected to a patient, the process being carried out with a supply arrangement comprising a first duct with a supply connection element, a second duct, a mixing point, an inspiration duct, a buffer reservoir with a supply chamber and a pneumatic control line, the pneumatic control line establishing a control fluid connection between the first duct and the buffer reservoir and acting on the buffer reservoir, the process comprising the steps of:

providing the first gas component at the supply connection element;

providing the second gas component;

directing the second gas component to the supply chamber such that the second gas component flows into the supply chamber and is guided from the supply chamber into the second duct;

directing the first gas component, in the first duct, from the supply connection element to the mixing point;

directing the second gas component, in the second duct, from the supply chamber to the mixing point;

directing the gas mixture comprising the first gas component and the second gas component from the mixing point through the inspiration duct to the patient-side coupling unit;

with the pneumatic control line acting on the buffer reservoir, effecting a pressure balancing between a pressure in the supply chamber, a pressure in the first duct and a pressure in the second duct; and

providing the buffer reservoir such that the buffer reservoir comprises a housing and a flexible fluid tight separating element inside the housing, the separating element fluid tightly dividing the interior of the housing into the supply chamber as a buffer volume and a control chamber as a control volume acting on the buffer volume,

wherein the control fluid connection pneumatically connects the control chamber to the first duct and causes a pressure balancing between the control chamber and the first duct,

wherein the separating element comprises a flexible bag,

wherein an interior space is formed between the housing and the bag, the interior space surrounding the bag;

wherein the supply chamber is formed inside the bag and the control chamber is formed in the interior space between the housing and the bag or the control chamber is formed inside the bag and the supply chamber is formed in the interior space between the housing and the bag.

14 . A process according to claim 13 ,

wherein the supply arrangement further comprises a third duct and a pressure reducer including an upstream pressure inlet and a downstream pressure outlet,

wherein a fluid connection is established or establishable between the upstream pressure inlet of the pressure reducer and a further source for the second gas component;

wherein the downstream pressure outlet of the pressure reducer is connected to the third duct;

wherein the third duct is configured to direct the second gas component from the downstream pressure outlet to the mixing point or to a further mixing point in fluid communication with the mixing point and/or with the patient-side coupling unit; and

wherein the pressure reducer is configured to provide the second gas component such that a time course of the pressure at the downstream pressure outlet follows a time course of the pressure in the first duct and/or a time course of the pressure in the second duct.

15 . A process according to claim 13 , further comprising:

providing a fluid delivery unit connected to the supply connection element;

connecting the patient-side coupling unit to the patient; and

ventilating the patient,

wherein the fluid delivery unit is configured to deliver the gas mixture generated by the supply arrangement to the patient-side coupling unit.