Systems and methods for measuring mitochondrial capacity

Patent metadata

Field	Value
Publication number	US-9706959-B2
Application number	US-201313793558-A
Country	US
Kind code	B2
Filing date	Mar 11, 2013
Priority date	Mar 9, 2012
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

In one embodiment, measuring mitochondrial capacity includes performing arterial occlusions on a patient, measuring oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin within the patient's body during the occlusions, calculating a blood volume correction factor that accounts for a change in blood volume that occurs during the arterial occlusions, and applying the correction factor to the measured oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measurements to obtain correct oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measurements.

First claim

The invention claimed is:

1. A system for measuring mitochondrial capacity, the system comprising:
a near-infrared spectroscopy device adapted to measure oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin of a patient during arterial occlusions; and
a computing device in communication with the near-infrared spectroscopy device that comprises a processor and memory for determining mitochondrial capacity, the memory comprising instructions stored thereon that when executed by the processor perform the steps of:
receive measurements of the oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measured by the near-infrared spectroscopy device,
calculating a blood volume correction factor that accounts for a change in blood volume that occurs during the arterial occlusions, and
apply the correction factor to the oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measurements to obtain corrected measurements, and calculating oxygen consumption using the corrected measurements.

2. The system of claim 1 , wherein calculating a blood volume correction factor comprises calculating a correction factor that adjusts the oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measurements so that a decrease in the oxygenated hemoglobin/myoglobin measurement is equivalent to an increase in the deoxygenated hemoglobin/myoglobin measurement.

3. The system of claim 1 , wherein calculating a blood volume correction factor comprises calculating the factor using the following equation:

β
i

=



O
2

⁢

Hb
i



(



O
2

⁢

Hb
i



+



HHb
i



)

where β is the blood volume correction factor, O 2 Hb is the oxygenated hemoglobin/myoglobin measurement, and HHb is the deoxygenated hemoglobin/myoglobin measurement.

4. The system of claim 3 , wherein applying the correction factor comprises calculating corrected oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measurements using the following equations:
O 2 Hb c = O 2 Hb −[ tHb *(1−β)]

HHb c = HHb −( tHb *β)

where O 2 Hb c , is the corrected oxygenated measurement, HHb c , is the corrected deoxygenated hemoglobin/myoglobin measurement, and tHb is the arithmetic sum of the O 2 Hb and HHb.

5. The system of claim 1 , wherein calculating a blood volume correction factor comprises calculating a global correction factor that will be applied to all measurements.

6. The system of claim 1 , wherein calculating a blood volume correction factor comprises calculating separate correction factors that will be individually applied to the measurements for each occlusion.

7. The system of claim 1 , wherein calculating a blood volume correction factor comprises iteratively searching for a blood volume correction factor that results in the smallest error for the difference between the oxygenated hemoglobin/myoglobin and deoxygenated hemoglobin/myoglobin measurements.

Assignees

• Univ Georgia

Inventors

• Mccully Kevin K
• Ryan Terence E

Classifications

• A61B5/6828

  Leg · CPC title

• A61B5/4884

  inducing physiological or psychological stress, e.g. applications for stress testing · CPC title

• A61B17/1355

  Automated control means therefor · CPC title

• A61B5/4519

  Muscles (measuring muscular strength A61B5/224; using electromyography [EMG] A61B5/389) · CPC title

• A61B5/4866 Primary

  Evaluating metabolism (using breath test A61B5/083) · CPC title