Traitement en cours

Veuillez attendre...

Paramétrages

Paramétrages

Aller à Demande

1. WO1997044072 - SYSTEME DE CONTROLE D'HEMODIALYSE POUR MACHINES D'HEMODIALYSE

Note: Texte fondé sur des processus automatiques de reconnaissance optique de caractères. Seule la version PDF a une valeur juridique

[ EN ]

CLAIMS
What is claimed is:

1. A method of obtaining an equilibrated dialysate sample whose metabolite concentration is the same as that of the plasma water of the blood of a patient, comprising the steps of:
stopping a dialysate flow to a dialyzer while allowing a blood pump to run and ultrafiltration to take place from the blood of a patient;
initially measuring the concentration of metabolite in said dialysate after partial equilibration to obtain a first sample from which concentration is measured;
measuring the metabolite concentration in the dialysate after a specified time has passed to obtain a second sample for which concentration is measured;
comparing the metabolite concentration in the second sample with the concentration in the first sample; and
continuing to sample until the difference between two successive samples is less than a specified amount.

2. The method as in clam 1 wherein said metabolite is urea.

3. A method for automatically obtaining the intercompartmental transfer coefficient for a patient undergoing hemodialysis treatment with a dialysis machine, comprising the steps of:
obtaining an equilibration sample by: a) stopping a dialysate flow to a dialyzer while allowing a blood pump to run and ulltrafiltration to take place with the blood of a patient; b) initially measuring the concentration of metabolite in said dialysate after partial equilibration to obtain a first sample from which concentration is measured; c) measuring the metabolite concentration in the dialysate after a specified time has passed to obtain a second sample for which concentration is measured; d) comparing the metabolite concentration in the second sample with the concentration in the first sample; and e) continuing to sample until the difference between two successive samples is less than a specified amount;
continuing to run the blood pump and the dialysis machine in bypass, and taking samples which have been equilibrated at regular time intervals;
determining the rate of change of metabolite concentration in the patient's blood, during a period when hemodialysis treatment has ceased, from said measurements; and
determining the ratio of the extra- and intra-cellular volumes (Rv) from said determined rate of change of metabolite concentration in the patient's blood.

4. The method as in claim 3 wherein said metabolite is urea.

5. The method as in claim 3 further comprising:
measuring blood concentration (Cbew) of metabolite at intervals during dialysis; and
determining Kl from the obtained equilibration samples and the blood concentration (Cbew) measurements using non-linear fitting techniques.

6. The method as in claim 3 further comprising:
measuring blood concentration (Cbew) of metabolite at intervals during dialysis; and
determining the intra- and extra-cellular volumes of a patient from the obtained equilibration samples and the blood concentration

(Cbew) measurements using non-linear fitting techniques.

7. The method as in claim 3 further comprising obtaining a pre-run equilibration sample to separate K and V once the ratio of K/V is known.

8. The method as in claim 3 further comprising obtaining a mid-run equilibration sample to obtain an estimate of K.

9. An apparatus for conducting equilibration of dialysate with a patient's blood for a patient undergoing hemodialysis, comprising:
first means of connecting to a dialysis machine for receiving a flow of dialysate therefrom;
first means for connecting said apparatus to a dialyzer cartridge and for directing said flow of dialysate from said dialysis machine to said dialyzer cartridge;
first means for connecting to said dialyzer cartridge and for receiving dialysate from said dialyzer cartridge;
second means for connecting to said dialysis machine for directing a flow of dialysate into said dialysis machine; and
bypass means selectively actuatable between two positions, a first position in which flow of dialysate is directed from said dialysis machine, through said dialyzer cartridge and returned to said dialysis machine, and a second position in which flow of dialysate is shunted away from said dialyzer cartridge to be returned to said dialyzer machine.

10. The apparatus as in claim 9 further comprising flow measuring means for measuring the flow of dialysate from said dialysis machine when said bypass means is in said second position.

11. The apparatus is in claim 9 further comprising mounting means for mounting the apparatus on a dialysis machine.

12. The apparatus as in claim 9 wherein said bypass means comprises a solenoid valve.