DEVICE AND PROCESS FOR CONTROLLING THE DEPTH OF SEDATION OF A MECHANICALLY RESPIRATED PATIENT

• US 20090177181A1
• Filed: 11/05/2008
• Published: 07/09/2009
• Est. Priority Date: 01/04/2008
• Status: Active Grant

• Current Assignee: Dragerwerk AG & Company KGaA (FPS Vermögensverwaltung GmbH)
• Original Assignee: Drager Medical AG & Co KG (Dragerwerk AG)
• Inventors: SCHMIDT, Hartmut
• Granted Patent: US 8,206,341 B2
• Time in Patent Office: Days
• US Class Current: 604/503
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/01 specially adapted for anaesthetising A61M16/104, A61M16/18 take precedence
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 2016/0033 electrical
• CPC Class Codes: A61M 2230/42 Rate
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

A device is provided for controlling the depth of sedation of a respirated patient. The device includes a respirator (2) and a sensor array (1) for detecting the tidal volume and/or the respiration rate of the patient being respirated. A computing unit (5) is provided for calculating the measured values determined with the sensor array (1). A drug regulating unit (3), a drug dispensing unit (4), and a central control device (6) are provided. The central control device (6) has stored desired values for the drug concentration to be dispensed as a function of a preselected depth of sedation corresponding to the corresponding variability over time of the tidal volume and/or respiration rate. The drug regulating unit (3) sets the drug dispensing unit (4) as a function of the tidal volume detected and/or the respiration rate for a preselected depth of sedation of the patient.

Claims

1. A device for controlling the depth of sedation of a mechanically respirated patient, the device comprising:

a respirator;

a sensor array for detecting a tidal volume and/or a respiration rate of the patient being respirated with said respirator;

a computing unit for calculating measured values detected with the sensor array;

a drug regulating unit;

a drug dispensing unit for dispensing a drug to the patient being respirated; and

a central control device with stored desired values for a drug concentration to be dispensed as a function of a preselected depth of sedation corresponding to a corresponding variability over time of the tidal volume and/or the respiration rate, wherein the drug regulating unit sets the drug dispensing unit as a function of the detected tidal volume and/or the respiration rate for a preselected depth of sedation of the patient.

2. A device in accordance with claim 1, wherein the measured values determined in the computing unit are calculated into parameters for the variability over time of the respiration rate and/or the tidal volume.

3. A device in accordance with claim 1, wherein classification or assessment rules for depths of sedation as a function of the measured variability over time of the respiration rate and/or tidal volume are stored in the central control device.

4. A device in accordance with claim 3, wherein the classification or assessment rules are based on scoring methods.

5. A device in accordance with claim 4, wherein the classification or assessment rules based on scoring methods comprise one of Ramsay Sedation Scale (RSS), Sedation Agitation Scale (SAS), Motor Activity Assessment Scale (MAAS), Vancouver Interaction and Calmness Scale (VICS), Richmond Agitation Sedation Score (RASS), and Cook-Palma Scale.

6. A device in accordance with claim 1, wherein therapy data corresponding to individual therapy protocols are additionally stored in the central control device with defined, prioritized depths of sedation for preset points in time.

7. A device in accordance with claim 1, wherein said sensor array is arranged in the respiration system of the respirator.

8. A device in accordance with claim 1, wherein said computing unit and said drug regulating unit comprise a single assembly unit.

9. A device in accordance with claim 1, wherein said drug dispensing unit is a microfluid pump or a piezoelectric dispensing unit.

10. A process of controlling the depth of sedation of a mechanically respirated patient, the process comprising the steps of:

inducing sedation using a preset drug dispensing, so that a desired depth of sedation corresponds to an actual depth of sedation;

closing a control circuit by switching on a drug regulating unit, so that a time-dependent tidal volume flow and/or respiration rate of the patient is measured;

calculating parameters for the variability over time of the tidal volume and/or the respiration rate from the measured values and determining corresponding depths of sedation by means of classification or assessment rules; and

setting drug dispensing for a preset desired depth of sedation based on stored rules for the relationship between the depth of sedation and the drug concentration to be dispensed.

11. A process of controlling the depth of sedation of a mechanically respirated patient, the process comprising the steps of:

providing a respirator and respirating a patient with said respirator;

providing a sensor array for detecting the tidal volume and/or a respiration rate of the patient being respirated with said respirator;

providing a computing unit;

calculating measured values detected with said sensor array using said computing unit;

providing a drug regulating unit;

providing a drug dispensing unit;

providing a central control device with stored desired values for a drug concentration to be dispensed as a function of a preselected depth of sedation corresponding to a corresponding variability over time of the tidal volume and/or the respiration rate;

dispensing a drug with the drug dispensing unit to the patient being respirated for inducing sedation using a preset drug dispensing rate having a desired depth of sedation corresponding to the actual depth of sedation;

switching on the drug regulating unit, so that a time-dependent tidal volume flow and/or the respiration rate of the patient is measured;

calculating parameters for the variability over time of the tidal volume and/or the respiration rate from the measured values and determining corresponding depths of sedation by means of classification or assessment rules using the central control device; and

setting drug dispensing for a preset desired depth of sedation based on stored rules for the relationship between the depth of sedation and the drug concentration to be dispensed wherein the drug regulating unit sets the drug dispensing unit as a function of the detected tidal volume and/or the respiration rate for the preselected depth of sedation of the patient.

12. A process in accordance with claim 11, wherein the measured values determined in the computing unit are calculated into parameters for the variability over time of the respiration rate and/or the tidal volume.

13. A process in accordance with claim 11, wherein classification or assessment rules for depths of sedation as a function of the measured variability over time of the respiration rate and/or tidal volume are stored in the central control device.

14. A process in accordance with claim 13, wherein the classification or assessment rules are based on scoring methods.

15. A process in accordance with claim 14, wherein the classification or assessment rules based on scoring methods comprise one of Ramsay Sedation Scale (RSS), Sedation Agitation Scale (SAS), Motor Activity Assessment Scale (MAAS), Vancouver Interaction and Calmness Scale (VICS), Richmond Agitation Sedation Score (RASS), and Cook-Palma Scale.

16. A process in accordance with claim 11, wherein therapy data corresponding to individual therapy protocols are additionally stored in the central control device with defined, prioritized depths of sedation for preset points in time.

17. A process in accordance with claim 11, wherein said sensor array is arranged in the respirator.

18. A process in accordance with claim 11, wherein said computing unit and said drug regulating unit comprise a single assembly unit.

19. A process in accordance with claim 11, wherein said drug dispensing unit is a microfluid pump or a piezoelectric dispensing unit.