Method and apparatus for determining blood oxygen transport
First Claim
Patent Images
1. A method for determining a patient'"'"'s blood oxygen transport, comprising:
- obtaining a blood sample from the patient;
measuring a rate of oxygen diffusion across a membrane of a red blood cell of the blood sample; and
correlating the measured rate with;
susceptibility to angina observed in a control population, or in the patient, at the measured rate; and
residence time of the blood in the heart during stress.
0 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates to a method and apparatus for determining blood oxygen transport, and to measure lipid levels by correlating these levels with the rate at which oxygen diffuses through the red blood cell membrane.
9 Citations
42 Claims
-
1. A method for determining a patient'"'"'s blood oxygen transport, comprising:
-
obtaining a blood sample from the patient;
measuring a rate of oxygen diffusion across a membrane of a red blood cell of the blood sample; and
correlating the measured rate with;
susceptibility to angina observed in a control population, or in the patient, at the measured rate; and
residence time of the blood in the heart during stress. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
exposing the red blood cell to oxygen;
exposing the red blood cell to an environment depleted of oxygen; and
monitoring either a blood level of oxygen, a level of oxygen bound to hemoglobin, or both.
-
-
3. The method of claim 2, wherein exposing the red blood cell to oxygen comprises circulating a blood sample in a closed loop diffusion chamber, the chamber housing an atmosphere comprising oxygen.
-
4. The method of claim 3, wherein the atmosphere comprising oxygen comprises atmospheric gas pressures.
-
5. The method of claim 4, wherein the gas pressures comprise about 160 mm Hg O2 and about 4 mm Hg CO2.
-
6. The method of claim 3, wherein the atmosphere comprising oxygen comprises capillary gas pressures.
-
7. The method of claim 6, wherein the gas pressures comprise about 23 mm Hg O2 and about 46 mm Hg CO2.
-
8. The method of claim 3, wherein circulating lasts for about 6 min.
-
9. The method of claim 2, wherein exposing the red blood cell to an environment depleted of oxygen comprises circulating a blood sample in a closed loop diffusion chamber, the chamber housing an atmosphere comprising nitrogen and depleted of oxygen.
-
10. The method of claim 9, wherein the atmosphere is supplied from a container of commercial grade nitrogen gas.
-
11. The method of claim 9, wherein circulating lasts for about 15 min.
-
12. The method of claim 2, wherein the step of exposing the red blood cell to oxygen precedes the step of exposing the red blood cell to an environment depleted of oxygen.
-
13. The method of claim 2, wherein the step of exposing the red blood cell to an environment depleted of oxygen precedes the step of exposing the red blood cell to oxygen.
-
14. The method of claim 1, wherein the measuring step is performed on a whole blood sample comprising anticoagulant.
-
15. An apparatus for measuring diffusion of oxygen across a red blood cell membrane comprising an oxygen level detector, a gas exchange system, and a red blood cell transport system;
-
the red blood cell transport system that transports a fluid containing red blood cells through the gas exchange system and the oxygen level detector, the red blood cell transport system comprising;
a) a sample receiving system to take in a sample of a red blood cell;
b) a pump that transports a red blood cell from the sample receiving system to the gas exchange system and the oxygen level detector;
the gas exchange system that couples to a gas source and exchanges a gas with the fluid containing the red blood cells at a rate faster than the rate at which the gas diffuses across a membrane of the red blood cell, the gas exchange system comprising;
a) a housing defining a gas inlet, a gas outlet, and a chamber;
b) a gas permeable tubing at least partially located within the housing for diffusing the gas from the chamber to a red blood cell contained within the gas permeable tubing;
wherein the gas permeable tubing comprises a lumen effective for containing red blood cells;
the housing exposing successive sample of red blood cells to the gases without cross-contamination between the samples;
the oxygen level detector that detects oxygen levels in a red blood cell or in fluid surrounding the red blood cell, the oxygen level detector comprising;
a) a light source producing light having an absorption free wavelength;
b) at least one filter;
c) photopickups to detect the transmission of light at the absorption free wavelength; and
a control system comprising a microprocessor electronically coupled to the oxygen level detector, the gas exchange system, and the red blood cell transport system to operably derive amounts of oxygen levels in a red blood cell, wherein the sample receiving system and the gas exchange system are present in a modular, cartridge-type insert, the cartridge-type insert being configured to be inserted into the apparatus for connection to the pump, the oxygen level detector and the control system, and removed from the apparatus for disposal. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
-
-
40. A method for determining a patient'"'"'s susceptibility to angina, comprising:
-
obtaining a blood sample from the patient;
measuring a rate of oxygen diffusion across a membrane of a red blood cell of the blood sample;
correlating the measured rate with the susceptibility to angina observed in a control population, or in the patient, at the measured rate; and
correlating the measured rate with residence time of the blood in the heart during stress. - View Dependent Claims (41)
exposing the red blood cell to oxygen;
exposing the red blood cell to an environment depleted of oxygen; and
monitoring either a blood level of oxygen, a level of oxygen bound to hemoglobin, or both.
-
-
42. A method for determining a patient'"'"'s blood oxygen transport, comprising:
-
obtaining a blood sample from the patient;
measuring a rate of oxygen diffusion across a membrane of a red blood cell of the blood sample; and
correlating the measured rate with established levels of blood lipid to determine the patient'"'"'s relative or absolute blood lipid level; and
further comprising comparing the patient'"'"'s lipid level to the patient'"'"'s previous lipid level measured at an earlier time to determine the patient'"'"'s blood oxygen transport.
-
Specification