Modification of sympathetic activation and/or respiratory function
Devices, systems and methods are disclosed for modifying sympathetic activation of a patient through alteration of respiratory function. In one form, a sub-apneic ventilation target for a ventilator is determined such that chronic sympathetic activation of the patient is mitigated.
1. A method for determining a sub-apneic ventilation target for a ventilator comprising the steps of:
setting a ventilation target to an initial value;
monitoring a patient's respiration for a duration;
analyzing data representing the patient's respiration to detect events indicating an apneic threshold;
if no events are detected, increasing the ventilation target and continue to monitor the patient's respiration for a duration;
if events are detected, setting a sub-apneic threshold and reducing the ventilation target to substantially the sub-apneic threshold or lower to determine the sub-apneic ventilation target;
wherein the determined sub-apneic ventilation target is such that chronic sympathetic activation of the patient is mitigated when ventilation is provided at substantially the determined sub-apneic ventilation target.
2. A method of claim 1 , wherein the sub-apneic threshold is initially set at an initial value and is subsequently reset based on the detected events to an updated sub-apneaic threshold.
3. The method of claim 2 , wherein the updated sub-apneic threshold is used to treat the patient.
4. The method of claim 1 , wherein the determined sub-apneic ventilation target is used to treat the patient.
5. The method of claim 1 , wherein the determined sub-apneic ventilation target is less than the sub-apneic threshold by an additional margin and is use to treat the patient.
6. The method of claim 1 , wherein the ventilation is substantially maintained at the determined sub-apneic ventilation target.
7. The method of claim 1 , wherein the determined sub-apneic ventilation target is adjusted as needed over time to be substantially at the sub-apneic threshold or lower.
8. The method of claim 1 , wherein the sub-apneic threshold will vary over time and the chronic sympathetic activation of the patient is substantially continuously mitigated by increasing or decreasing the sub-apneic ventilation target as needed over time.
9. The method of claim 1 , wherein the method is computer implemented.
10. The method of claim 1 , wherein the events are detected using an apnea hypopnea index.
11. The method of claim 1 , wherein the events are detected when a hypopnea index is above a threshold.
12. The method of claim 1 , wherein the events are detected when an apnea index is above a threshold.
13. The method of claim 1 , wherein the events are detected when a patient's breath rate is below a threshold.
14. The method of claim 1 , wherein the events are detected when the ventilator mode switches to a timed mode.
15. The method of claim 1 , wherein the events are detected when an apnea hypopnea index is above a threshold a predetermined number of times.
16. The method of claim 1 , wherein the events are detected when a hypopnea index is above a threshold a predetermined number of times.
17. The method of claim 1 , wherein the events are detected when an apnea index is above a threshold a predetermined number of times.
18. The method of claim 1 , wherein the events are detected when the patient's breath rate is below a threshold a predetermined number of times.
19. A method of treating a patient for chronic sympathetic activation by setting a sub-apneic ventilation target of a ventilator in accordance with claim 1 .
20. The method of claim 19 , wherein the patient is asleep.
21. The method of claim 19 , wherein the patient is awake.
22. The method of claim 1 , wherein the ventilator is a bilevel ventilator.
23. A method of treating a patient for one or more of the conditions selected from the group consisting of hypertension, Type II diabetes, obesity, metabolic syndrome, and congestive heart failure, by setting a sub-apneic ventilation target of a ventilator in accordance with claim 1 .
24. The method of claim 1 , wherein the initial value for the ventilation target or the sub-apneic ventilation threshold is set to one or more values selected from the group consisting of a nominal physiological value, a value calculated using a formula; a value determined from a table; the patient's respiration value, and a stored value from a previous treatment session.
25. A processor-readable medium having instructions therein that, when executed, cause a processor to control a ventilator to treat a patient for chronic sympathetic activation by setting a sub-apneic ventilation target of the ventilator in accordance with the method of claim 1 .
26. The processor-readable medium of claim 25 , wherein the patient is asleep.
27. The processor-readable medium of claim 25 , wherein the patient is awake.
28. The processor-readable medium of claim 25 , wherein the ventilator is a bilevel ventilator.
29. A processor-readable medium having instructions therein that, when executed, cause a processor to control a ventilator to treat a patient for one or more of the conditions selected from the group consisting of hypertension, Type II diabetes, obesity, metabolic syndrome, and congestive heart failure, by setting a sub-apneic ventilation target of the ventilator in accordance with the method of claim 1 .
30. A device for treating a patient for chronic sympathetic activation by setting a sub-apneic ventilation target of a ventilator in accordance with the method of claim.
31. A device for treating a patient for one or more of the conditions selected from the group consisting of hypertension, Type II diabetes, obesity, metabolic syndrome, and congestive heart failure, by setting a sub-apneic ventilation target of a ventilator in accordance with the method of claim 1 .
32. The method of claim 1 , wherein the patient is not being treated for OSA.
33. The method of claim 1 , wherein the patient is also being treated for OSA.
34. The method of claim 1 , wherein the patient does not have OSA.
35. The method of claim 1 , wherein the patient does have OSA.
36. A processor-readable medium having instructions therein that, when executed, cause a processor to perform the steps of:
setting a ventilation target to an initial value;
monitoring a patient's respiration for a duration;
analyzing data representing the patient's respiration to detect events indicating an apneic threshold;
if no events are detected, increasing the ventilation target and continuing to monitor the patient's respiration;
if events are detected, setting a sub-apneic threshold and reducing the ventilation target to substantially the sub-apneic threshold or lower to determine a sub-apneic ventilation target;
wherein the sub-apneic ventilation target is such that chronic sympathetic activation of the patient is mitigated when ventilation is provided at substantially the sub-apneic ventilation target.
37. The processor-readable medium of claim 36 , wherein the events are detected when an apnea hypopnea index is above a threshold.
38. The processor-readable medium d of claim 36 , wherein the events are detected when a hypopnea index is above a threshold.
39. The processor-readable medium of claim 36 , wherein the events are detected when an apnea index is above a threshold.
40. The processor-readable medium of claim 36 , wherein the events are detected when the patient's breath rate is below a threshold.
41. The processor-readable medium of claim 36 , wherein the events are detected when an apnea hypopnea index is above a threshold a predetermined number of times.
42. The processor-readable medium of claim 36 , wherein the events are detected when a hypopnea index is above a threshold a predetermined number of times.
43. The processor-readable medium of claim 36 , wherein the events are detected when an apnea index is above a threshold a predetermined number of times.
44. The processor-readable medium of claim 36 , wherein the events are detected when a patient's breath rate is below a threshold a predetermined number of times.
45. The processor-readable medium of claim 36 , wherein the initial value is set to one or more values selected from the group consisting of a nominal physiological value, a value calculated using a formula; a value determined from a table; the patient's respiration value, and a stored value from a previous treatment session.
46. The processor-readable medium of claim 36 , wherein patient is not being treated for OSA.
47. The processor-readable medium of claim 36 , wherein the patient is also being treated for OSA.
48. The processor-readable medium of claim 36 , wherein the patient does not have OSA.
49. The processor-readable medium of claim 36 , wherein the patient does have OSA.
50. A device for determining a sub-apneic ventilation target for a ventilator comprising:
a blower in air communication with a mask worn by a patient;
a respiratory monitor;
a processor in communication with the respiratory monitor and the blower, wherein the processor controls the operation of the blower; and
a memory connected to the processor, wherein the memory has instructions therein that cause the processor to perform the steps of,
setting a ventilation target to an initial value;
monitoring the patient's respiration for a duration;
analyzing data representing the patient's respiration to detect events indicating an apneic threshold;
if no events are detected, increasing the ventilation target;
if events are detected, setting a sub-apneic threshold and reducing the ventilation target to substantially the sub-apneic threshold or lower to determine the sub-apneic ventilation target;
wherein the sub-apneic ventilation target is such that chronic sympathetic activation of the patient is mitigated when ventilation is provided at the sub-apneic ventilation target.
51. The device of claim 50 , wherein the events are detected when an apnea hypopnea index is above a threshold.
52. The device of claim 50 , wherein the events are detected when a hypopnea index is above a threshold.
53. The device of claim 50 , wherein the events are detected when an apnea index is above a threshold.
54. The device of claim 50 , wherein the events are detected when the patient's breath rate is below a threshold.
55. The device of claim 50 , wherein the events are detected when an apnea hypopnea index is above a threshold a predetermined number of times.
56. The device of claim 50 , wherein the events are detected when a hypopnea index is above a threshold a predetermined number of times.
57. The device of claim 50 , wherein the events are detected when an apnea index is above a threshold a predetermined number of times.
58. The device of claim 50 , wherein the events are detected when a patient's breath rate is below a threshold a predetermined number of times.
59. The device of claim 50 , wherein the patient is asleep.
60. The device of claim 50 , wherein the patient is awake.
61. The device of claim 50 , wherein the ventilator is a bilevel ventilator.
62. The device of claim 50 , wherein the initial value is set to one or more values selected from the group consisting of a nominal physiological value, a value calculated using a formula; a value determined from a table; the patient's respiration value, and a stored value from a previous treatment session.
63. The device of claim 50 , wherein the patient is not being treated for OSA.
64. The device of claim 50 , wherein the patient is also being treated for OSA.
65. The device of claim 50 , wherein the patient does not have OSA.
66. The device of claim 50 , wherein the patient does have OSA.