Method of determining hypoxia

• US 8,945,824 B2
• Filed: 04/11/2008
• Issued: 02/03/2015
• Est. Priority Date: 10/13/2006
• Status: Active Grant

• Current Assignee: Calmark Sweden AB
• Original Assignee: Calmark Sweden AB
• Inventors: Karlsson, Mathias, Hiort af Orns, Sofia
• Primary Examiner(s): Shen, Bin
• Application Number:
  US12/101,470
• Publication Number:
  US 20080213744A1
• Time in Patent Office: 2,489 Days
• Field of Search: 435/4, 435/26
• US Class Current: 435/4
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 10/0048 for taking amniotic fluid samples
• CPC Class Codes: A61B 2503/02 Foetus
• CPC Class Codes: A61B 5/1405 Devices for taking blood samples devices for taking samples of other body liquids A61B10/0045
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/150015 Source of blood
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: A61B 5/412 Detecting or monitoring sepsis
• CPC Class Codes: A61B 5/4362 Assessing foetal parameters
• CPC Class Codes: A61F 7/00 Heating or cooling appliances for medical or therapeutic treatment of the human body heating or cooling means in connection with bedsteads or mattresses A47C21/00 ; massage, therapeutic baths A61H; hyperthermia using electric or magnetic fields or ultrasound A61N; electric heating elements H05B
• CPC Class Codes: C12Q 1/32 involving dehydrogenase
• CPC Class Codes: C12Q 1/52 involving transaminase
• CPC Class Codes: G01N 2333/904 acting on CHOH groups as donors, e.g. glucose oxidase, lactate dehydrogenase (1.1)
• CPC Class Codes: G01N 2333/91188 transferring nitrogenous groups (2.6)
• CPC Class Codes: G01N 2800/2871 Cerebrovascular disorders, e.g. stroke, cerebral infarct, cerebral haemorrhage, transient ischemic event
• CPC Class Codes: G01N 2800/7038 Hypoxia
• CPC Class Codes: G01N 33/492 Determining multiple analytes
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: G01N 33/573 for enzymes or isoenzymes

Abstract

A method of determining hypoxia in fetal scalp blood sampled during labor comprises the determination of total lactate dehydrogenase (LDH) in plasma obtained from the sample. The method can comprise the additional determination of K, Mg, Ca, AST, ALT, lactate in the plasma and/or blood. Increased values of one or more of LDH, Mg, Ca, AST, ALT, lactate are indicative of hypoxia in the fetus. Also disclosed is the use of a plasma separation apparatus in the method.

Claims

1. A method of assessing hypoxia in a gastrointestinal tract of a mammal, comprising:

a. collecting a blood sample from the gastrointestinal tract, said blood sample comprising plasma and blood cells;

b. separating the plasma from the blood cells;

c. determining the amount of lactate dehydrogenase (LDH) in the plasma and comparing the amount of lactate dehydrogenase with lactate dehydrogenase in a control sample;

d. assessing the presence of hypoxia at the gastrointestinal tract from the amount of LDH in the plasma; and

e. identifying a location of anastomosis based on the assessment of hypoxia at the gastrointestinal tract.

2. The method of claim 1, further comprising determining the amount of at least one additional prognostic marker in the plasma selected from the group consisting essentially of K, Mg, Ca, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate.

3. The method of claim 1, wherein the volume of the blood sample comprises from 5 μ

L to 150 μ

L.

4. The method of claim 1, wherein the volume of the blood sample comprises from 5 μ

L to 25 μ

L.

5. The method of claim 1, wherein the volume of the blood sample comprises from about 5 to 15 μ

L.

6. The method of claim 1, wherein the plasma is separated from the blood cells by means of a semi-permeable membrane such that the plasma passes through the membrane and the blood cells are retained on the membrane.

7. The method of claim 1, wherein the blood sample is collected from a mammal'"'"'s colorectal.

8. The method of claim 7, wherein the blood sample is collected prior to a medical procedure and further comprising:

a. collecting a second blood sample after a medical procedure, said blood sample comprising plasma and blood cells;

b. separating the plasma from the blood cells of the second blood sample; and

c. determining the total amount of LDH in the plasma of the second blood sample.

9. The method of claim 8, wherein the medical procedure comprises anastomosis of the gastrointestinal tract.

10. A method of assessing hypoxia at a tissue site of a mammal, comprising:

a. collecting a blood sample from the tissue site, said blood sample comprising plasma and blood cells;

b. separating the plasma from the blood cells;

c. determining the amount of LDH in the plasma and comparing the amount of lactate dehydrogenase with lactate dehydrogenase in a control sample; and

d. assessing the presence of hypoxia at the tissue site from the amount of LDH in the plasma, and wherein the blood sample is collected prior to a medical procedure and further comprising;

e. collecting a second blood sample after a medical procedure, said blood sample comprising plasma and blood cells;

f. separating the plasma from the blood cells of the second blood sample; and

g. determining the total amount of LDH in the plasma of the second blood sample and further comprising determining the amount of at least one additional prognostic marker in the plasma of both blood samples selected from the group consisting essentially of K, Mg, Ca, AST, ALT and lactate; and

performing a medical procedure on the mammal based on the assessment of the presence of hypoxia at the tissue site.

11. The method of claim 10, further comprising comparing the amount of the prognostic markers in the blood samples.

12. The method of claim 10, further comprising determining the amount of at least one additional prognostic marker in the plasma selected from the group consisting essentially of K, Mg, Ca, AST, ALT and lactate.

13. The method of claim 12, further comprising determining the amount of ALT in the plasma.

14. A method of performing an anastomosis procedure on a patient in need thereof;

collecting a first blood sample from tissue in a portion of a gastrointestinal tract in patient, said blood sample comprising plasma and blood cells;

determining a reference value for the amount of lactate dehydrogenase (LDH) in the plasma from said first blood sample for said tissue;

removing a portion of the patient'"'"'s gastrointestinal tract;

collecting a second blood sample from tissue in the gastrointestinal tract of the patient, said second blood sample comprising plasma and blood cells;

analyzing the amount of LDH in plasma of the second blood sample to determine the amount of LDH in the plasma from said second blood sample; and

comparing the reference value to the amount of LDH in plasma of the second blood sample, and selecting a location for anastomosis based on the comparison of the reference value to the amount of LDH in plasma of the second blood sample.

15. The method of claim 14, wherein the step of removing a portion of the patient'"'"'s gastrointestinal tract also includes the step of removing a tumor.

16. The method of claim 14, further comprising deteimining the amount of at least one additional prognostic marker in the plasma selected from the group consisting essentially of K, Mg, Ca, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate.

17. The method of claim 14, wherein the volume of the blood sample for each of the first and second blood samples comprises from about 5 μ

L to 150 μ

L.

18. The method of claim 14, wherein the volume of the blood sample for each of the first and second blood samples comprises from about 5 μ

L to 25 μ

L.

19. The method of claim 14, wherein the volume of the blood sample for each of the first and second blood samples comprises from about 5 to 15 μ

L.

20. The method of claim 14, wherein the plasma is separated from the blood cells by means of a semi-permeable membrane such that the plasma passes through the membrane and the blood cells are retained on the membrane.