Extracorporeal whole body hyperthermia using alpha-stat regulation of blood pH and pCO2

• US RE38,203 E1
• Filed: 10/07/1999
• Issued: 07/22/2003
• Est. Priority Date: 08/28/1995
• Status: Expired due to Fees

• Current Assignee: First Circle Medical, Inc.
• Original Assignee: First Circle Medical, Inc.
• Inventors: Kelly, Theodore C.
• Primary Examiner(s): Sykes, Angela D.
• Assistant Examiner(s): Bianco, Patricia
• Application Number:
  US09/415,902
• Time in Patent Office: 1,384 Days
• Field of Search: 604/4.01, 604/6.13, 604/6.14, 604/6.16, 604/504, 604/506-8, 128/898, 607/106, 600/301, 600/529, 600/549, 600/483-84
• US Class Current: 604/4.01
• CPC Class Codes: A61M 1/369 Temperature treatment
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 2230/202 partial carbon oxide pressure, e.g. partial dioxide pressure (P-CO2)
• CPC Class Codes: A61M 2230/205 partial oxygen pressure (P-O2)

Abstract

A device and method for extracorporeal whole body hyperthermia treatment of a patient'"'"'s blood using alpha-stat regulation of blood pH and pCO₂ is described. The respiratory rate of a patient is either increased or decreased in accordance with the changes in pH, pCO₂, and base excess. The regulation of blood during the hyperthermic treatment of the patient'"'"'s blood stabilizes the biochemical reactions fundamental to the metabolic welfare of the organisms within the patient'"'"'s blood while the viruses within the patient'"'"'s blood are eliminated.

Claims

1. A method of extracorporeal treatment of a patient, comprising the steps of:

(a) cannulating a patient for extracorporeal blood circulation wherein a blood flow circuit is defined between a first point of cannulation and a second point of cannulation;

(b) then pumping a patient'"'"'s blood through the blood flow circuit;

(c) monitoring a patient'"'"'s temperature, blood pressure, and a flow rate of blood as the patient'"'"'s blood passes through the blood flow circuit;

(d) as the patient'"'"'s blood is monitored, heating the patient'"'"'s blood in the blood flow circuit to an elevated temperature;

then

(e) measuring blood pH, partial pressure of CO₂ gas in the patient'"'"'s blood (pCO₂), and HCO₃⁻

concentration in the patient'"'"'s blood;

(f) calculating a base excess from the pH, pCO₂, and HCO₃⁻

concentration of the patient'"'"'s blood measured in step (e); and

then

(g) adjusting a respiratory rate of the patient and administration of a concentration of NaHCO₃ in the patient'"'"'s blood as a function of at least one of a change in the blood pH, a change in the pCO₂, and a change in the base excess.

2. The method as in claim 1, wherein the step of adjusting a respiratory rate of the patient comprises decreasing said respiratory rate when at least one of an increase in blood pH, a decrease in pCO₂ and an increase in the base excess is determined from steps (e) and (f).

3. The method as in claim 1, wherein the step of adjusting a respiratory rate of the patient comprises decreasing said respiratory rate when at least one of a decrease in blood pH, a decrease in pCO₂ and a decrease in the base excess is determined from steps (e) and (f).

4. The method as in claim 3, further comprising the step of increasing the HCO₃⁻

ion concentration when the base excess of the patient'"'"'s blood calculated in step (f) is determined to be decreasing with a change in body temperature of the patient.

5. The method as in claim 1, wherein the step of adjusting a respiratory rate of the patient comprises increasing said respiratory rate when at least one of a decrease in blood pH, an increase in pCO₂ and a decrease in the base excess is determined from steps (e) and (f).

6. The method as in claim 5, further comprising the step of increasing the HCO₃⁻

ion concentration when the base excess of the patient'"'"'s blood calculated in step (f) is determined to be decreasing with a change in body temperature of the patient.

7. The method as in claim 1, wherein the step of adjusting the respiratory rate of the patient comprises increasing said respiratory rate when an increase in blood pH, an increase in pCO₂ and an increase in the base excess is determined from steps (e) and (f).

8. The method as in claim 1, wherein the step of adjusting administration of a concentration of NaHCO₃ comprises increasing the concentration of NaHCO₃ when the base excess is determined to be decreasing as the patients body temperature is raised.

9. The method as in claim 1, further comprising the step of increasing a concentration of acidotic crystalloid when the base excess of the patient'"'"'s blood is determined to be increasing with a change in body temperature of the patient.

10. A method of extracorporeal treatment of a patient comprising:

(a) circulating the patient'"'"'s blood from the patient through an extracorporeal blood flow circuit, and back to the patient, wherein the blood returned to the patient has been heated within the blood flow circuit to an elevated temperature range;

(b) measuring blood pH, partial pressure of CO₂ gas in the patient'"'"'s blood (pCO₂), and HCO₃⁻

concentration in the patient'"'"'s blood;

(c) calculating a base excess from the pH, pCO₂, and HCO₃⁻

concentration of the patient'"'"'s blood measured in step (b);

and

(d) adjusting a respiratory rate of the patient and administration of a concentration of NaHCO₃ in the patient'"'"'s blood as a function of at least one of a change in the blood pH, a change in the pCO₂, and a change in the base excess.

11. The method as in claim 10, wherein the pCO₂ of the blood is normalized at 37°

C.

12. The method as in claim 10, wherein the base excess is normalized at 37°

C.

13. The method as in claim 10, wherein the pH is normalized at 37°

C.

14. The method as in claim 10, wherein the respiratory rate of the patient is adjusted as a function of a change in the pCO₂ of the blood.

15. The method as in claim 10, wherein the administration of a concentration of NaHCO₃ in the patient'"'"'s blood is adjusted as a function of a change in the base excess.

16. The method as in claim 10, wherein the respiratory rate of the patient is adjusted as a function of a change in the pCO₂ of the blood and the administration of a concentration of NaHCO₃ in the patient'"'"'s blood is adjusted as a function of a change in the base excess.

17. The method as in claim 10, wherein the respiratory rate of the patient is adjusted through ventilation.

18. The method as in claim 10, wherein the respiratory rate of the patient is adjusted through medications.