Method for detecting filter clogging by using pressure information, apparatus for monitoring filter clogging and bed-side system

• US 20060157408A1
• Filed: 02/11/2004
• Published: 07/20/2006
• Est. Priority Date: 02/19/2003
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Kuroda, Yasuhiro, Akutagawa, Masatake, Kinouchi, Yohsuke, Okahisa, Toshiya, Ohnishi, Yoshiaki
• Granted Patent: US 7,632,411 B2
• Time in Patent Office: Days
• US Class Current: 210/636
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 2205/707 Testing of filters for clogging
• CPC Class Codes: B01D 61/22 Controlling or regulating
• CPC Class Codes: B01D 65/10 Testing of membranes or membrane apparatus; Detecting or repairing leaks
• CPC Class Codes: B01D 65/109 Testing of membrane fouling or clogging, e.g. amount or affinity

Abstract

A method is provided for detecting filter clogging which are able to keep track of the filter clogging with precision and in detail. At least one pressure selected from the group consisting of a pressure Pa in a blood inflow portion (32a), a pressure Pv in a blood outflow portion (32b), a pressure Pf1 in a filtrate inflow portion (32c), and a pressure Pf2 in a filtrate outflow portion (32d) is measured continuously, then a variation (pressure waveform) of the pressure is analyzed, a clogging of a filter (32) is detected using the analyzed result. Thereby a clogging of a filter is detected early. As a result, it is possible to prevent from developing of the filter clogging by controlling a dosage amount of anti-coagulant properly and changing a flow rate of blood. The variation of the pressure wave may be analyzed by subjecting the variable to Fast Fourier Transform.

Claims

1. A method for detecting a filter clogging composed of hollow-fiber membrane, which has a blood inflow portion, a blood outflow portion, a filtrate inflow portion, and a filtrate outflow portion, which filters a blood by passing the blood, said method comprising the steps of:

1) continuous measuring at least one pressure selected from the group consisting of a pressure in said blood inflow portion, a pressure in said blood outflow portion, a pressure in said filtrate inflow portion, and a pressure in said filtrate outflow portion;

2) analyzing a variation of the measured pressure in the measuring step; and

3) detecting a filter clogging using an analyzed result in the analyzing step.

2. The method according to claim 1, wherein a transformed value is calculated by subjecting the variation to Fast Fourier Transform in the analyzing step.

3. The method according to claim 2, wherein a filter clogging is detected using a transformed value corresponding to pulsing frequently in at least one of the blood inflow portion and the filtrate outflow portion in the detecting step.

4. The method according to claim 3, wherein a filter clogging is detected using amplitude and/or power of the transformed value in the detecting step.

5. The method according to claim 4, wherein a filter clogging is detected using a ratio of amplitude and/or power in at least two of the blood inflow portion, the blood outflow portion, the filtrate inflow portion, and the filtrate outflow portion in the detecting step.

6. The method according to claim 3, wherein a filter clogging is detected using a phase of the transformed value in the detecting step.

7. The method according to claim 6, wherein a filter clogging is detected using a difference of phase in at least two of the blood inflow portion, the blood outflow portion, the filtrate inflow portion, and the filtrate outflow portion in the detecting step.

8. An apparatus for monitoring a filter clogging comprising:

detecting means for detecting a filter clogging by a method according to claim 1;

displaying means for displaying the filter clogging on the basis of a detected result of the detecting means; and

monitoring means for monitoring the filter clogging on the basis of the detected result of the detecting means.

9. A bed-side system comprising the apparatus according to claim 8.