Method and implantable system for blood-glucose concentration monitoring using parallel methodologies
In an implantable medical device for monitoring glucose concentration in the blood, a blood-glucose concentration analysis is performed using correlations of blood-glucose concentration with measures of metabolic oxygen consumption including oxymetric, and/or temperature. Analysis of electrocardiographic data is used in a parallel method to detect and/or confirm the onset and/or existence and/or extent of hypoglycemia and/or hyperglycemia. Blood-glucose concentration calculation is enhanced by using the combination of the oxygen metabolism analysis and electrocardiographic analysis.
1. A method, for use by an implantable medical device, for monitoring a level of blood-glucose concentration, the method comprising:
(a) generating a first metric of blood-glucose concentration by monitoring one or more property of one or more cardiac electrical signal;
(b) generating a second metric of blood-glucose concentration by monitoring one or more property of oxygen metabolism;
(c) using one of the first metric of blood-glucose concentration or the second metric of blood-glucose concentration to detect one of hypoglycemia, normoglycemia or hyperglycemia; and
(d) using the other one of first metric of blood-glucose concentration or the second metric of blood-glucose concentration to confirm or not confirm the detection at step (c) of the one of hypoglycemia, normoglycemia or hyperglycemia.
2. The method of claim 1 , wherein step (a) comprises generating the first metric of blood-glucose concentration by analyzing at least one of: a T-wave amplitude, a Q-T interval, or an S-T segment deviation.
3. The method of claim 1 , wherein step (b) comprises generating the second metric of blood-glucose concentration using a metabolic oxygen conformation method which utilizes cardiac output, temperature and blood-oxygen data in combination with stored information regarding a relationship of the cardiac output, temperature and blood-oxygen data to blood-glucose concentration.
4. The method of claim 1 , wherein step (b) comprises generating the second metric of blood-glucose concentration by monitoring at least one of: a metric of venous oxygen saturation, a metric of hematocrit, or a metric of arterial oxygen saturation.
5. The method of claim 1 , wherein step (d) comprises using the first metric of blood-glucose concentration to confirm a detection at step (c) that used the second metric of blood-glucose concentration if both the first metric of blood-glucose concentration and the second metric of blood-glucose concentration are indicative of the same one of hypoglycemia, normoglycemia or hyperglycemia.
6. The method of claim 1 , wherein step (d) comprises using the second metric of blood-glucose concentration to confirm a detection at step (c) that used the first metric of blood-glucose concentration if both the first metric of blood-glucose concentration and the second metric of blood-glucose concentration are indicative of the same one of hypoglycemia, normoglycemia or hyperglycemia.
7. The method of claim 1 , wherein step (a) is performed a plurality of times; step (b) is performed in response to generating at step (a) a first metric of blood-glucose concentration that is used at step (c) to detect one of hypoglycemia or hyperglycemia; and step (d) is performed in response to generating at step (b) a second metric of blood-glucose concentration.
8. The method of claim 1 , wherein step (b) is performed a plurality of times; step (a) is performed in response to generating at step (b) a second metric of blood-glucose concentration that is used at step (c) to detect one of hypoglycemia or hyperglycemia; and step (d) is performed in response to generating at step (a) a first metric of blood-glucose concentration.
9. The method of claim 1 , further comprising controlling a therapy in response to the detection at step (c), and confirmation at step (d), of the one of hypoglycemia, normoglycemia or hyperglycemia.
10. The method of claim 1 , further comprising generating a warning signal if one of hypoglycemia or hyperglycemia is detected at step (c) and confirmed at step (d).
11. A method, for use by an implantable medical device, for monitoring a level of blood-glucose concentration, the method comprising:
(a) generating a first measure of blood-glucose concentration by analyzing one or more property of one or more cardiac electrical signal;
(b) generating a second measure of blood-glucose concentration by analyzing at least one of venous oxygen saturation, hematocrit, or arterial oxygen saturation; and
(c) using one of the first measure of blood-glucose concentration or the second measure of blood-glucose concentration to detect one of hypoglycemia, normoglycemia or hyperglycemia; and
(d) using the other one of first measure of blood-glucose concentration or the second measure of blood-glucose concentration to confirm or not confirm the detection at step (c) of the one of hypoglycemia, normoglycemia or hyperglycemia.
12. The method of claim 11 , wherein step (b) comprises generating the second measure of blood-glucose concentration using a metabolic oxygen conformation method which utilizes cardiac output, temperature and blood-oxygen data in combination with stored information regarding a relationship of the cardiac output, temperature and blood-oxygen data to blood-glucose concentration.
13. The method of claim 11 , wherein step (d) comprises using the other one of the first measure of blood-glucose concentration or the second measure of blood-glucose concentration to confirm the detection at step (c) of the one of hypoglycemia, normoglycemia or hyperglycemia if both the first measure of blood-glucose concentration and the second measure of blood-glucose concentration are indicative of the same one of hypoglycemia, normoglycemia or hyperglycemia.
14. The method of claim 11 , wherein step (a) comprises generating the first measure of blood-glucose concentration by analyzing at least one of: a T-wave amplitude, a Q-T interval, or an S-T segment deviation.
15. The method of claim 11 , wherein:
step (a) is performed repeatedly;
step (b) is initiated in response to generating at step (a) a first measure of blood-glucose concentration that is used at step (c) to detect one of hypoglycemia or hyperglycemia; and
step (d) is initiated upon completion of step (c).
16. The method of claim 11 , wherein:
step (b) is performed repeatedly;
step (a) is initiated in response to generating at step (b) a second measure of blood-glucose concentration that is used at step (c) to detect one of hypoglycemia or hyperglycemia; and
step (d) is initiated upon completion of step (c).
17. The method of claim 11 , further comprising controlling a therapy in response to the detection at step (c), and confirmation at step (d), of the one of hypoglycemia, normoglycemia or hyperglycemia.
18. The method of claim 11 , further comprising generating a warning signal if one of hypoglycemia or hyperglycemia is detected at step (c) and confirmed at step (d).
19. A method, for use by an implantable medical device, for monitoring a level of blood-glucose concentration, the method comprising:
(a) generating a first measure of blood-glucose concentration dependent on one or more property of one or more cardiac electrical signal;
(b) generating a second measure of blood-glucose concentration dependent on one or more of venous oxygen saturation, hematocrit, or arterial oxygen saturation measured using an implanted oxymeter; and
(c) using one of the first measure of blood-glucose concentration or the second measure of blood-glucose concentration to detect one of hypoglycemia, normoglycemia or hyperglycemia; and
(d) using the other one of first measure of blood-glucose concentration or the second measure of blood-glucose concentration to confirm or not confirm the detection at step (c) of the one of hypoglycemia, normoglycemia or hyperglycemia.
20. The method of claim 19 , wherein step (a) comprises generating the first measure of blood-glucose concentration dependent on at least one of: a T-wave amplitude, a Q-T interval, or an S-T segment deviation.