초록 ▼

A medical ventilator system and method that triggers, cycles, or both based on patient effort, which is determined from cross-correlating patient flow and patient pressure. The medical ventilator is also controlled such that sensitivity to a patient initiated trigger increases as the expiratory phas

A medical ventilator system and method that triggers, cycles, or both based on patient effort, which is determined from cross-correlating patient flow and patient pressure. The medical ventilator is also controlled such that sensitivity to a patient initiated trigger increases as the expiratory phase of the breathing cycle progresses. The present invention also provides adaptive adjustment of cycling criteria to optimize the cycling operation.

대표청구항 ▼

A medical ventilator system and method that triggers, cycles, or both based on patient effort, which is determined from cross-correlating patient flow and patient pressure. The medical ventilator is also controlled such that sensitivity to a patient initiated trigger increases as the expiratory phas

A medical ventilator system and method that triggers, cycles, or both based on patient effort, which is determined from cross-correlating patient flow and patient pressure. The medical ventilator is also controlled such that sensitivity to a patient initiated trigger increases as the expiratory phase of the breathing cycle progresses. The present invention also provides adaptive adjustment of cycling criteria to optimize the cycling operation. to claim 1, wherein the measuring means is adapted to determine the respiratory gas flow (VA,VB,VC) by measuring the maxima in the inhalation phase and formation of their arithmetic mean value. 7. The device according to claim 1 for adjusting the optimal air pressure (Popt) in a respirator in which a maximally required therapy pressure is adjusted. 8. The device according to claim 7, wherein the pressure (P) is increased if the pressure (P) lies below the optimal pressure (Popt), the pressure (P) is maintained if the pressure (P) is the optimal pressure (Popt) and the pressure (P) is not decreased if the pressure (P) lies above the optimal pressure (Popt). 9. The device according to claim 1 for adjusting the optimal air pressure (Popt) in a respirator in which the pressure (P) is adapted to changing requirements of the patient. 10. The device according to claim 9, wherein the applied pressure (P) is increased if the applied pressure (P) lies below the optimal pressure (Popt), the pressure (P) is decreased if the applied pressure (P) lies above the optimal pressure (Popt), and the pressure (P) is maintained if the applied pressure.(P) is the optimal pressure (Popt). 11. The device according to claim 7 wherein a reaction to the result of the device only takes place if a plurality of equal results are obtained. 12. A device for assessing the applied air pressure (P) during automatic respiration through positive airway pressure comprising (a) an adjusting means for varying the applied pressure (P) so that at least three different pressure values (A, B, C) can be adjusted, and for adjusting the optimal air pressure (Popt) in a respirator in which a maximally required therapy pressure is adjusted, (b) a measuring means for measuring the respiratory flow (V) for the three different pressure values (A, B, C), wherein three corresponding respiratory gas flow values (VA,VB,VC) are obtained, and (c) an assessing means for assessing on the basis of the relation:of the measured respiratory gas flow values (VA,VB,VC) to each other whether the applied air pressure (P) lies below or above the optimal air pressure (Popt) or whether it is the optimal air pressure (Popt). 13. The device according to claim 12, wherein the assessing means is adapted (a) to assess that the pressure (P) lies below the optimal pressure (Popt) if it is true that k·VB>VAand k·VA>VC (b) to assess that the pressure (P) lies above the optimal pressure (Popt) if it is true that k·VBAand k·VAC (c) and in case of all other values of the respiratory gas flow curve (V), to assess that the pressure (P) is the optimal pressure. (Popt), wherein kAVB,VC) by means of the regression analysis. 15. The device according to claim 14, wherein the assessing means is adapted (a) to calculate the regression straight-line on the basis of the respiratory gas flow values (VA,VB,VC), (b) to calculate the confidence interval of the gradient of the regression straight-line at the position of one of the adjusted pressure values (A,B, C), (ci) to assess that the pressure (P) lies below the optimal pressure (Popt) if both limits of the confidence interval are >0, (c2) to assess that the pressure (P) lies above the optimal pressure (Popt) if both limits of the confidence interval are opt) if the limits of the confidence interval have different signs. 16. The device according to claim 12 which is adapted to operate in the following steps: (1) measuring the respiratory gas flow (VA) by means of the measuring means during a predetermined number of breaths, thereby maintaining the value A, (2) increasing the air pressure (P) by means of the adjusting means to the value B and measuring the respiratory gas flow (VB) during the same number of breaths as in step (1), and (3) decreasing the air pressure (P) by means of the adjusting means to the value C and measuring the respiratory gas flow (VC) during the same number of breaths as in step (1). 17. The device according to claim 12, wherein the adjusting means is adapted to adjust 4 mbar as pressure value A, 6 mbar as pressure value B and 2 mbar as pressure value C. 18. The device according to claim 12, wherein the measuring means is adapted to determine the respiratory gas flow (VA,VB,VC) by measuring the maxima in the inhalation phase and formation of their arithmetic mean value. 19. The device according to claim 12, wherein the pressure (P) is increased if the pressure (P) lies below the optimal pressure (Popt), the pressure (P) is maintained if the pressure (P) is the optimal pressure (Popt) and the pressure (P) is not decreased if the pressure (P) lies above the optimal pressure (Popt). 20. The device according to claim 12 for adjusting the optimal air pressure (Popt) in a respirator in which the pressure (P) is adapted to changing requirements of the patient. 21. The device according to claim 20, wherein the applied pressure (P) is increased if the applied pressure (P) lies below the optimal pressure (Popt), the pressure (P) is decreased if the applied pressure (P) lies above the optimal pressure (Popt), and the pressure (P) is maintained if the applied pressure (P) is the optimal pressure (Popt). 22. The device according to claim 12 wherein a reaction to the result of the device only takes place if a plurality of equal results are obtained. armaceutical agent to be applied or at least one diagnostic agent. 11. A device as claimed in claims 1 or 2 wherein said base element includes a plurality of recesses therein. 12. A device as claimed in claims 1 or 2 wherein said base element includes a plurality of recesses therein and wherein platelets or cellulose sponges are provided in said recesses as substrates for pharmaceutical and/or diagnostic agents. 13. A device as claimed in claims 1 or 2 wherein said base element includes a plurality of recesses therein and wherein transmucosal and/or nasal therapeutic reservoirs are provided in said recesses as substrates for pharmaceutical and/or diagnostic agents. 14. A device as claimed in claims 1 or 2 wherein a second base element is provided connected to said first base element to form a single unit. 15. A method for improving nasal breathing and/or for applying pharmaceutical or diagnostic agents in the nose comprising inserting a substantially flat or slightly arched plate-shaped base element into the nose which deforms into a u-shaped member applied partly against the nasal septum and the applied partly against the nasal outer wall and impregnating said base element with a pharmaceutical and/or diagnostic agent. 16. The method according to claim 15 wherein said base material includes a plurality of recesses and said pharmaceutical and/or diagnostic agent is contained within said recesses.