JP4811183B2

JP4811183B2 - Hemodialysis machine

Info

Publication number: JP4811183B2
Application number: JP2006210536A
Authority: JP
Inventors: 敦池田
Original assignee: JMS Co Ltd
Current assignee: JMS Co Ltd
Priority date: 2006-08-02
Filing date: 2006-08-02
Publication date: 2011-11-09
Anticipated expiration: 2026-08-02
Also published as: JP2008035930A

Description

本発明は血液処理装置に関し、特に血液透析の際に生じ易い過剰な除水や逆の除水不足を防止するように除水条件、例えば除水速度をコントロールすることが可能な血液透析装置に関する。 The present invention relates to a blood treatment apparatus, and more particularly to a hemodialysis apparatus capable of controlling a water removal condition, for example, a water removal speed so as to prevent excessive water removal or conversely insufficient water removal that is likely to occur during hemodialysis.

本発明者は、先に血液パラメータを計測する血液計測手段、血液処理を行う実働手段、および実働手段の血液処理を制御する制御手段を有して構成され、かつ血液量（ＢＶ値）または血液量（ＢＶ値）の変化量を指標値（以下、血液指標値ともいう）として透析条件を制御して血液透析処理を行う血液透析装置であって、目標とすべき前記血液指標値の経時的進路を目標制御線として設定し、該経時的進路における各計測時点（制御時点）における血液指標値を計測し、かつ、該計測した血液指標値と該計測時点（制御時点）の次の計測時点（制御時点）における目標とする血液指標値を利用して次の計測時点（制御時点）の目標血液指標値に到達するように透析条件を算出して、該透析条件によって血液透析処理を行うことを特徴とする血液透析装置を提供している（特許文献１）。この血液透析装置は血液透析の際に生じ易い過剰な除水や逆の除水不足を防止するように、除水条件、例えば除水速度を容易にコントロールすることが可能な血液透析装置である。
特開２００１−５４０号公報 The present inventor is configured to have blood measuring means for measuring blood parameters, working means for performing blood processing, and control means for controlling blood processing of the working means, and blood volume (BV value) or blood. A hemodialysis apparatus that performs hemodialysis treatment by controlling dialysis conditions using an amount of change in the amount (BV value) as an index value (hereinafter also referred to as a blood index value), and the blood index value to be targeted over time The course is set as a target control line, the blood index value at each measurement time point (control time point) in the time course is measured, and the measured blood index value and the next measurement time point after the measurement time point (control time point) Using the target blood index value at the (control time), calculating the dialysis condition so as to reach the target blood index value at the next measurement time (control time), and performing hemodialysis treatment according to the dialysis condition Characterized by blood Provides a dialyzer (Patent Document 1). This hemodialysis apparatus is a hemodialysis apparatus that can easily control the water removal conditions, for example, the water removal speed, so as to prevent excessive water removal and conversely insufficient water removal that are likely to occur during hemodialysis.
Japanese Patent Laid-Open No. 2001-540

前記本発明者が提案した血液透析装置は、血液透析の際に生じ易い過剰な除水や逆の除水不足を防止するように除水条件を容易にコントロールすることが可能な血液透析装置であるが、透析条件を制御する制御手段における制御プログラムは初期血液量（ＢＶ₀）を予測して設定する必要がある。しかしながら、各患者の初期血液量（ＢＶ₀）を正確に予測することは困難で、そのためには複雑な操作を必要とする。これに対して簡易な初期血液量（ＢＶ₀）の算出方法を使用すると算出した初期血液量（ＢＶ₀）は患者の実際の初期血液量（ＢＶ₀）とかけ離れたものになり、制御誤差に繋がる恐れがある。したがって、本発明の目的は、前記課題を解決した初期血液量（ＢＶ₀）を使用しなくても、血液量（ＢＶ値）または血液量（ＢＶ値）の変化量を指標値とする制御プログラムにより透析条件を制御して血液透析処理を行う血液透析装置を提供することにある。 The hemodialysis apparatus proposed by the present inventor is a hemodialysis apparatus capable of easily controlling the water removal conditions so as to prevent excessive water removal or reverse water shortage that is likely to occur during hemodialysis. However, the control program in the control means for controlling the dialysis conditions needs to predict and set the initial blood volume (BV ₀ ). However, it is difficult to accurately predict the initial blood volume (BV ₀ ) of each patient, which requires complicated operations. Simple primary blood volume contrast (BV ₀₎ Initial blood volume was calculated using the calculation method (BV ₀₎ becomes that far from the actual initial blood volume of the patient (BV _0), the control error There is a risk of being connected. Therefore, an object of the present invention is to provide a control program that uses the blood volume (BV value) or the amount of change in blood volume (BV value) as an index value without using the initial blood volume (BV ₀ ) that solves the above problems. It is intended to provide a hemodialysis apparatus that performs hemodialysis treatment by controlling dialysis conditions.

本発明は血液パラメータを計測する血液計測手段、血液処理を行う実働手段および実働手段の血液処理を制御する制御手段を有して構成され、かつ前記制御手段が３個以上の制御周期を継時的に設定し、かつ下式（ａ）を利用する制御プログラムに基づいて血液透析条件を制御するものであることを特徴とする血液透析装置を提供することにより、前記技術課題を解決することができた。
〔式中、Ｕ１は制御周期ｎにおける除水速度、Ｕ２は制御周期ｎの次の制御周期ｎ＋１における除水速度、Ｕ３は制御周期ｎ＋１の次の制御周期ｎ＋２における目標の除水速度を意味する。Δ（ΔＢＶｎ％）は制御周期ｎの終点のΔＢＶｎ％と制御周期ｎの開始点ΔＢＶｎ−１％の差、Δ（ΔＢＶｎ＋１％）は制御周期ｎ＋１の終点のΔＢＶｎ＋１％と制御周期ｎ＋１の開始点のΔＢＶｎ％の差、Δ（ΔＢＶｎ＋２’％）は制御周期ｎ＋２で目標とするΔＢＶｎ＋２’％と制御周期ｎ＋２の開始点のΔＢＶｎ＋１％の差を意味する。ｎは１以上の整数を意味する〕 The present invention comprises blood measuring means for measuring blood parameters, working means for performing blood processing, and control means for controlling blood processing of the working means, and the control means continues over three or more control cycles. The above-mentioned technical problem can be solved by providing a hemodialysis apparatus characterized in that hemodialysis conditions are controlled based on a control program that is automatically set and uses the following equation (a) did it.
[In the formula, U1 represents the water removal speed in the control cycle n, U2 represents the water removal speed in the control cycle n + 1 next to the control cycle n, and U3 represents the target water removal speed in the control cycle n + 2 next to the control cycle n + 1. . Δ (ΔBVn%) is the difference between ΔBVn% at the end of control cycle n and the start point ΔBVn-1% of control cycle n, and Δ (ΔBVn + 1%) is the difference between ΔBVn + 1% at the end of control cycle n + 1 and the start point of control cycle n + 1. The difference of ΔBVn%, Δ (ΔBVn + 2 ′%) means the difference between ΔBVn + 2 ′% targeted in the control cycle n + 2 and ΔBVn + 1% of the start point of the control cycle n + 2. n means an integer of 1 or more.

前記式（ａ）の算出法を図１に基づいて説明する。
図１においてΔＴで区画される継時的に連続した３つの等時間の制御周期（ｎ＝１）を設定した。ただし、前記３つの制御周期は等時間のものとして構成したが、必ずしも等時間でなくてもよい。制御周期ｎ、制御周期ｎ＋１および制御周期ｎ＋２の各間隔ΔＴは患者のＰＲＲ（ＰｌａｓｍａＲｅｆｉｌｌｉｎｇＲａｔｅ：血漿が体内から血管に再補充される速度）に実質的な差が無い程度に短くかつ同一時間ΔＴで設定される。 The calculation method of the said Formula (a) is demonstrated based on FIG.
In FIG. 1, three equal time control periods (n = 1) that are continuous in time divided by ΔT are set. However, although the three control cycles are configured to be of equal time, they need not necessarily be of equal time. The intervals ΔT of the control cycle n, the control cycle n + 1, and the control cycle n + 2 are so short that there is no substantial difference in the patient's PRR (Plasma Refilling Rate), and the same time ΔT. Set by.

初期血液量をＢＶ₀とした場合に下記式（１）〜（３）が成立する。
｛ＢＶ₀×Δ（ΔＢＶｎ％）｝／ΔＴ＝Ｕ１−ＵＦＲ１（１）
｛ＢＶ₀×Δ（ΔＢＶｎ＋１％）｝／ΔＴ＝Ｕ２−ＵＦＲ２（２）
（ＢＶ₀×ΔＢＶ３％）／ΔＴ＝Ｕ３−ＵＦＲ３（３）
Δ（ΔＢＶｎ％）／Δ（ΔＢＶｎ＋１％）＝（Ｕ１−ＰＲＲ）／（Ｕ２−ＰＲＲ）（４）
Δ（ΔＢＶｎ＋１％）／Δ（ΔＢＶｎ＋２’％）＝（Ｕ２−ＰＲＲ）／（Ｕ３−ＰＲＲ）（５） When the initial blood volume is BV ₀ , the following formulas (1) to (3) are established.
{BV ₀ × Δ (ΔBVn%)} / ΔT = U1−UFR1 (1)
{BV ₀ × Δ (ΔBVn + 1%)} / ΔT = U2−UFR2 (2)
(BV ₀ × ΔBV3%) / ΔT = U3−UFR3 (3)
Δ (ΔBVn%) / Δ (ΔBVn + 1%) = (U1-PRR) / (U2-PRR) (4)
Δ (ΔBVn + 1%) / Δ (ΔBVn + 2 ′%) = (U2−PRR) / (U3−PRR) (5)

前記（４）式を変形すると、
Δ（ΔＢＶｎ％）（Ｕ２−ＰＲＲ）＝Δ（ΔＢＶｎ＋１％）（Ｕ１−ＰＲＲ）
｛Δ（ΔＢＶｎ％）×Ｕ２−Δ（ΔＢＶｎ＋１％）×Ｕ１｝＝ＰＲＲ｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）｝（４’）
前記（５）式を変形すると、
Δ（ΔＢＶｎ＋１％）（Ｕ３−ＰＲＲ）＝Δ（ΔＢＶｎ＋２’％）（Ｕ２−ＰＲＲ）
｛Δ（ΔＢＶｎ＋１％）×Ｕ３−Δ（ΔＢＶｎ＋２’％）×Ｕ２｝＝ＰＲＲ｛Δ（ΔＢＶｎ＋１％）−Δ（ΔＢＶｎ＋２’％）｝（５’） When the equation (4) is transformed,
Δ (ΔBVn%) (U2-PRR) = Δ (ΔBVn + 1%) (U1-PRR)
{Δ (ΔBVn%) × U2−Δ (ΔBVn + 1%) × U1} = PRR {Δ (ΔBVn%) − Δ (ΔBVn + 1%)} (4 ′)
When the equation (5) is transformed,
Δ (ΔBVn + 1%) (U3-PRR) = Δ (ΔBVn + 2 ′%) (U2-PRR)
{Δ (ΔBVn + 1%) × U3−Δ (ΔBVn + 2 ′%) × U2} = PRR {Δ (ΔBVn + 1%) − Δ (ΔBVn + 2 ′%)} (5 ′)

前記（４’）式および（５’）式を利用して、以下のようにしてその値の算出が困難なＰＲＲ値を消去して、かつ各パラメータを利用し易いように式を下式（６）〜（１１）と変形することにより、前式（ａ）を得ることができた。
〔｛Δ（ΔＢＶｎ％）×Ｕ２−Δ（ΔＢＶｎ＋１％）×Ｕ１｝〕／〔｛Δ（ΔＢＶｎ＋１％）×Ｕ３−Δ（ΔＢＶｎ＋２’％）×Ｕ２｝〕＝〔｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）｝〕／〔｛Δ（ΔＢＶｎ＋１％）−Δ（ΔＢＶｎ＋２’％）｝〕（６）
〔｛Δ（ΔＢＶｎ％）×Ｕ２−Δ（ΔＢＶｎ＋１％）×Ｕ１｝×｛Δ（ΔＢＶｎ＋１％）−Δ（ΔＢＶｎ＋２’％）｝〕／｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）｝＝｛Δ（ΔＢＶｎ＋１％）×Ｕ３−Δ（ΔＢＶｎ＋２’％）×Ｕ２｝（７）
Δ（ΔＢＶｎ＋１％）×Ｕ３＝〔｛Δ（ΔＢＶｎ％）×Ｕ２−Δ（ΔＢＶｎ＋１％）×Ｕ１｝×｛Δ（ΔＢＶｎ＋１％）−Δ（ΔＢＶｎ＋２’％）｝〕／｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）｝＋｛Δ（ΔＢＶｎ＋２’％）×Ｕ２｝（８） Using the above equations (4 ′) and (5 ′), the following equations are used to eliminate PRR values that are difficult to calculate as follows and to easily use each parameter: By transforming from 6) to (11), the previous formula (a) could be obtained.
[{Δ (ΔBVn%) × U2−Δ (ΔBVn + 1%) × U1}] / [{Δ (ΔBVn + 1%) × U3−Δ (ΔBVn + 2 ′%) × U2}] = [{Δ (ΔBVn%) − Δ (ΔBVn + 1%)}] / [{Δ (ΔBVn + 1%) − Δ (ΔBVn + 2 ′%)}] (6)
[{Δ (ΔBVn%) × U2−Δ (ΔBVn + 1%) × U1} × {Δ (ΔBVn + 1%) − Δ (ΔBVn + 2 ′%)}] / {Δ (ΔBVn%) − Δ (ΔBVn + 1%)} = { Δ (ΔBVn + 1%) × U3−Δ (ΔBVn + 2 ′%) × U2} (7)
Δ (ΔBVn + 1%) × U3 = [{Δ (ΔBVn + 1%) × U2−Δ (ΔBVn + 1%) × U1} × {Δ (ΔBVn + 1%) − Δ (ΔBVn + 2 ′%)}] / {Δ (ΔBVn%) − Δ (ΔBVn + 1%)} + {Δ (ΔBVn + 2 ′%) × U2} (8)

Ｕ３＝〔{Δ（ΔＢＶｎ％）×Δ（ΔＢＶｎ＋１％）×Ｕ２}−｛Δ（ΔＢＶｎ＋１％）×Δ（ΔＢＶｎ＋１％）×Ｕ１｝−｛Δ（ΔＢＶｎ％）×Δ（ΔＢＶｎ＋２’％）×Ｕ２｝＋｛Δ（ΔＢＶｎ＋１％）×Δ（ΔＢＶｎ＋２’％）×Ｕ１｝＋｛Δ（ΔＢＶｎ％）×Δ（ΔＢＶｎ＋２’％）×Ｕ２｝２−｛Δ（ΔＢＶｎ＋１％）×Δ（ΔＢＶｎ＋２’％）×Ｕ２｝〕／〔｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）｝×｛Δ（ΔＢＶｎ＋１％）｝〕（９）
Ｕ３＝〔{Δ（ΔＢＶｎ％）×Δ（ΔＢＶｎ＋１％）×Ｕ２}−｛Δ（ΔＢＶｎ＋１％）×Δ（ΔＢＶｎ＋１％）×Ｕ１｝＋｛Δ（ΔＢＶｎ＋１％）×Δ（ΔＢＶｎ＋２’％）×Ｕ２｝−｛Δ（ΔＢＶｎ＋１％）×Δ（ΔＢＶｎ＋２’％）×Ｕ２｝〕／〔{Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）}×｛Δ（ΔＢＶｎ＋１％）｝〕（１０）
Ｕ３＝〔{Δ（ΔＢＶｎ％）×Ｕ２}−｛Δ（ΔＢＶｎ＋１％）×Ｕ１｝＋｛Δ（ΔＢＶｎ＋２’％）×Ｕ１｝−｛Δ（ΔＢＶｎ＋２’％）×Ｕ２｝〕／｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶＮ＋１％）｝（１１）
Ｕ３＝〔Ｕ２×｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋２’％）｝−Ｕ１×｛Δ（ΔＢＶｎ＋１％）−Δ（ΔＢＶｎ＋２’％）｝〕／｛Δ（ΔＢＶｎ％）−Δ（ΔＢＶｎ＋１％）｝・・・・・（ａ） U3 = [{Δ (ΔBVn%) × Δ (ΔBVn + 1%) × U2} − {Δ (ΔBVn + 1%) × Δ (ΔBVn + 1%) × U1} − {Δ (ΔBVn%) × Δ (ΔBVn + 2 ′%) × U2 } + {Δ (ΔBVn + 1%) × Δ (ΔBVn + 2 ′%) × U1} + {Δ (ΔBVn%) × Δ (ΔBVn + 2 ′%) × U2} 2- {Δ (ΔBVn + 1%) × Δ (ΔBVn + 2 ′%) × U2}] / [{Δ (ΔBVn%) − Δ (ΔBVn + 1%)} × {Δ (ΔBVn + 1%)}] (9)
U3 = [{Δ (ΔBVn + 1%) × Δ (ΔBVn + 1%) × U2} − {Δ (ΔBVn + 1%) × Δ (ΔBVn + 1%) × U1} + {Δ (ΔBVn + 1%) × Δ (ΔBVn + 2 ′%) × U2 } − {Δ (ΔBVn + 1%) × Δ (ΔBVn + 2 ′%) × U2}] / [{Δ (ΔBVn%) − Δ (ΔBVn + 1%)} × {Δ (ΔBVn + 1%)}] (10)
U3 = [{Δ (ΔBVn%) × U2} − {Δ (ΔBVn + 1%) × U1} + {Δ (ΔBVn + 2 ′%) × U1} − {Δ (ΔBVn + 2 ′%) × U2}] / {Δ (ΔBVn %) − Δ (ΔBVN + 1%)} (11)
U3 = [U2 × {Δ (ΔBVn%) − Δ (ΔBVn + 2 ′%)} − U1 × {Δ (ΔBVn + 1%) − Δ (ΔBVn + 2 ′%)}] / {Δ (ΔBVn%) − Δ (ΔBVn + 1%) } (A)

本発明の血液透析装置において、初期血液量（ＢＶ₀）を必要としない制御プログラムとして前記式（ａ）の他に、下記式（ｂ）を使用する制御プログラムが挙げられる。
Ｕ３＝｛Δ（ΔＢＶｎ＋２’％）／Δ（ΔＢＶｎ＋１％）｝×Ｕ２×ｋ（ｂ）
前式（ｂ）は以下のようにして導き出される。
前記３個の制御周期において、第２周期のΔ（ΔＢＶｎ＋１％）と第３周期の目標Δ（ΔＢＶｎ＋２’％）の比は除水速度の比であると考え導き出したが、実際にはΔ（ΔＢＶ％）は除水速度とＰＲＲの差であり、単純な除水速度の比例関係にない。そのためＵ１とΔ（ΔＢＶｎ％）を基にＵ３を求めた場合とＵ２とΔ（ΔＢＶｎ＋１％）を基にＵ３を求めた場合ではＵ３の値が異なったものとなる。前記Ｕ１とΔ（ΔＢＶｎ％）を基にＵ３を求めた場合の値をＵ３’、前記Δ（ΔＢＶｎ＋１％）を基にＵ３を求めた場合の値をＵ３’’とした場合、Ｕ３’とＵ３’’の比がＰＲＲの影響と考えられる。したがってＵ１→Ｕ２の変化の関係がＵ２→Ｕ３の関係に引き継がれると仮定して、補正係数（ｋ）をｋ＝Ｕ３’／Ｕ３’’
＝（Δ（ΔＢＶｎ％）×Ｕ２／Δ（ΔＢＶｎ＋１％）×Ｕ１）で計算して前記式（ｂ）を導き出すことができる。特に前記式（ａ）においてΔ（ΔＢＶｎ％）＝Δ（ΔＢＶｎ＋１％）の場合、不定形となりＵ３は算出不能となるが、前式（ｂ）を使用することによって制御可能となる。この場合、補正係数（ｋ）＝１となり、前式（ｂ）は下式（ｃ）で表される。
Ｕ３＝（Δ（ΔＢＶｎ＋２’％）／Δ（ΔＢＶｎ＋１％））×Ｕ２・・・・・・・・・・・・（ｃ）
前式（ｃ）による制御は、Δ（ΔＢＶｎ％）＝Δ（ΔＢＶｎ＋１％）で前式（ａ）による制御が不能の場合に特に有用である。 In the hemodialysis apparatus of the present invention, as a control program that does not require the initial blood volume (BV ₀ ), there is a control program that uses the following formula (b) in addition to the formula (a).
U3 = {Δ (ΔBVn + 2 ′%) / Δ (ΔBVn + 1%)} × U2 × k (b)
The previous equation (b) is derived as follows.
In the three control cycles, the ratio of Δ (ΔBVn + 1%) in the second cycle and the target Δ (ΔBVn + 2 ′%) in the third cycle was derived as a ratio of the water removal speed. ΔBV%) is the difference between the water removal rate and the PRR, and is not proportional to the simple water removal rate. For this reason, the value of U3 differs between U3 obtained based on U1 and Δ (ΔBVn%) and U3 obtained based on U2 and Δ (ΔBVn + 1%). When U3 ′ is a value when U3 is obtained based on U1 and Δ (ΔBVn%), and U3 ″ is a value when U3 is obtained based on Δ (ΔBVn + 1%), U3 ′ and U3 The ratio of '' is considered to be the effect of PRR. Therefore, assuming that the relationship of change of U1 → U2 is inherited by the relationship of U2 → U3, the correction coefficient (k) is set to k = U3 ′ / U3 ″.
= (Δ (ΔBVn%) × U2 / Δ (ΔBVn + 1%) × U1) can be used to derive the equation (b). In particular, when Δ (ΔBVn%) = Δ (ΔBVn + 1%) in the above formula (a), it becomes indefinite and U3 cannot be calculated, but it can be controlled by using the previous formula (b). In this case, the correction coefficient (k) = 1, and the previous equation (b) is expressed by the following equation (c).
U3 = (Δ (ΔBVn + 2 ′%) / Δ (ΔBVn + 1%)) × U2 (c)
The control according to the previous equation (c) is particularly useful when Δ (ΔBVn%) = Δ (ΔBVn + 1%) and the control according to the previous equation (a) is impossible.

以下、本発明の血液透析装置において利用する血液量（ＢｌｏｏｄＶｏｌｕｍｅ、ＢＶ）、ΔＢＶ％、およびΔ（ΔＢＶ％）について説明する。
（１）ＢＶ値
患者の循環する血液量を示すものである。
（２）ΔＢＶ％
血液量の単位時間当たりの変化量であるΔＢＶの割合を意味し下式（ｄ）で表され、所期血液量を使用することなく、Ｈｃｔ値（ヘマトクリット値）を測定することにより計測することができる。
ΔＢＶ％＝｛（透析開始時のＨｃｔ／計測時のＨｃｔ）−１｝×１００・・・・・（ｄ） Hereinafter, the blood volume (Blood Volume, BV), ΔBV%, and Δ (ΔBV%) used in the hemodialysis apparatus of the present invention will be described.
(1) BV value This indicates the amount of blood circulating in the patient.
(2) ΔBV%
The ratio of ΔBV, which is the amount of change in blood volume per unit time, is expressed by the following formula (d) and is measured by measuring the Hct value (hematocrit value) without using the desired blood volume. Can do.
ΔBV% = {(Hct at the start of dialysis / Hct at the time of measurement) −1} × 100 (d)

前記（ｄ）式は以下のようにして導き出すことができる。
Ｈｃｔ（開始時）＝赤血球数（開始時）／ＢＶ（開始時）・・・（ｍ）
Ｈｃｔ（現在時）＝赤血球数（現在時）／ＢＶ（現在時）・・・（ｎ）
血液開始時と血液開始後の現在時に赤血球数に変化が無いと仮定すれば、前記（ｍ）式と（ｎ）式より以下の（ｐ）式が成立する。
Ｈｃｔ（開始時）／Ｈｃｔ（現在時）＝ＢＶ（現在時）／ＢＶ（開始時）・・・（ｐ）
また、ΔＢＶ％は下式（ｑ）で表すことができる。
ΔＢＶ％＝［（ＢＶ（現在時）−ＢＶ（開始時））／ＢＶ（開始時）］×１００・・・（ｑ）
前記（ｑ）式を変形すると下式（ｒ）で表すことができる。
ΔＢＶ％＝［（ＢＶ（現在時）／ＢＶ（開始時））−１］×１００・・・（ｒ）
前記式（ｒ）に前記式（ｐ）を代入すると、前記式（ｄ）を導き出すことができる。
（３）Δ（ΔＢＶ％）
各制御周期の開始点と終了点のΔＢＶ％の差を意味し、例えば制御周期ｎのΔ（ΔＢＶ％）はΔ（ΔＢＶｎ％）と表し、制御周期ｎの終点のΔＢＶｎ％と制御周期１の開始点のΔＢＶｎ−１％との差を意味し、また、制御周期ｎ＋１のΔ（ΔＢＶ％）はΔ（ΔＢＶＮ＋１％）と表し、制御周期ｎ＋１の終点のΔＢＶｎ＋１％と制御周期ｎ＋１の開始点のΔＢＶｎ％との差を意味する。さらに制御周期ｎ＋２の目標Δ（ΔＢＶ％）は制御周期ｎ＋２で目標とするΔＢＶｎ＋２’％と制御周期ｎ＋２の開始点のΔＢＶｎ＋１％との差を意味する。 The equation (d) can be derived as follows.
Hct (at start) = Red blood cell count (at start) / BV (at start) (m)
Hct (current time) = Red blood cell count (current time) / BV (current time) (n)
Assuming that there is no change in the number of red blood cells at the start of blood and at the present time after the start of blood, the following expression (p) is established from the expressions (m) and (n).
Hct (at start) / Hct (current time) = BV (current time) / BV (at start time) (p)
ΔBV% can be expressed by the following equation (q).
ΔBV% = [(BV (current time) −BV (start time)) / BV (start time)] × 100 (q)
When the equation (q) is modified, it can be expressed by the following equation (r).
ΔBV% = [(BV (current time) / BV (starting time)) − 1] × 100 (r)
When the formula (p) is substituted into the formula (r), the formula (d) can be derived.
(3) Δ (ΔBV%)
It means the difference between ΔBV% of the start point and end point of each control cycle. For example, Δ (ΔBV%) of the control cycle n is expressed as Δ (ΔBVn%), and ΔBVn% of the end point of the control cycle n and the control cycle 1 It means a difference from ΔBVn−1% of the start point, and Δ (ΔBV%) of the control cycle n + 1 is expressed as Δ (ΔBVN + 1%), and ΔBVn + 1% of the end point of the control cycle n + 1 and the start point of the control cycle n + 1 It means the difference from ΔBVn%. Further, the target Δ (ΔBV%) of the control cycle n + 2 means a difference between ΔBVn + 2 ′% targeted in the control cycle n + 2 and ΔBVn + 1% of the starting point of the control cycle n + 2.

以下、本発明の血液透析装置の制御態様を図１に基づいて説明する。
図１に血液透析開始後の最初の制御周期である第１番目の制御周期１、該制御周期１の次の制御周期である第２番目の制御周期２、および該制御周期２の次の制御周期である第３番目の制御周期３を示す（ΔＢＶｎ％、ΔＢＶｎ＋１％およびΔＢＶｎ＋２％のｎが１の場合）。各制御周期は継時的にΔＴ間隔で設定されるが、前記ΔＴ間隔は等時間でなくてもよい。図１の横軸は時間であり、縦軸はΔＢＶ％である。血液透析開始後、最初の３個の制御周期においてはＵ３を求めるためのパラメータであるΔ（ΔＢＶ１％）とΔ（ΔＢＶ２％）の値は既知の値でないので、制御周期１でＵ１および制御周期２でＵ２の既知の除水速度で除水を行いΔ（ΔＢＶ１％）とΔ（ΔＢＶ２％）の値を取得し、また第３番目の制御周期３に設定した目標ΔＢＶ３％に基づいて該目標ΔＢＶ３％に到達するために必要な目標Δ（ΔＢＶ３’％）を算出した後、前記式（ａ）によりＵ３を求めた。 Hereinafter, the control mode of the hemodialysis apparatus of the present invention will be described with reference to FIG.
FIG. 1 shows a first control cycle 1 that is the first control cycle after the start of hemodialysis, a second control cycle 2 that is the control cycle next to the control cycle 1, and a control that follows the control cycle 2. A third control cycle 3 is shown (when n of ΔBVn%, ΔBVn + 1%, and ΔBVn + 2% is 1). Each control cycle is set at intervals of ΔT over time, but the intervals of ΔT need not be equal. The horizontal axis in FIG. 1 is time, and the vertical axis is ΔBV%. Since the values of Δ (ΔBV1%) and Δ (ΔBV2%), which are parameters for obtaining U3, are not known values in the first three control cycles after the start of hemodialysis, U1 and the control cycle in control cycle 1 2 to remove water at a known water removal speed of U2 to obtain values of Δ (ΔBV1%) and Δ (ΔBV2%), and based on the target ΔBV3% set in the third control cycle 3 After calculating the target Δ (ΔBV3 ′%) necessary to reach ΔBV3%, U3 was determined by the above equation (a).

次に第２図に示すように制御周期２、３および４の制御周期を３個の制御周期として（ΔＢＶｎ％、ΔＢＶｎ＋１％およびΔＢＶｎ＋２％のｎが２の場合）、前記制御周期１、２および３を制御周期とする場合と同様にして第３制御周期に相当する制御周期４の目標Δ（ΔＢＶ４’％）を算出した後、前記式（ａ）によりＵ４を求めた。この場合、制御周期４の目標ΔＢＶ％に基づいて該目標ΔＢＶ％に到達するために必要な目標ΔＢＶ₄’％を算出した後、前記式（ａ）によりＵ４を求めた。この場合第２周期に相当する制御周期３のΔ（ΔＢＶ３％）としては、前記Ｕ３で除水した場合に計測したΔ（ΔＢＶ％）値を採用した。 Next, as shown in FIG. 2, the control cycles 2, 3 and 4 are set to three control cycles (when ΔBVn%, ΔBVn + 1% and ΔBVn + 2% n is 2), the control cycles 1, 2 and Similarly to the case where 3 is set as the control cycle, the target Δ (ΔBV4 ′%) of the control cycle 4 corresponding to the third control cycle is calculated, and then U4 is obtained by the above equation (a). In this case, after calculating the target ΔBV ₄ ′% necessary to reach the target ΔBV% based on the target ΔBV% of the control cycle 4, U4 was obtained from the above equation (a). In this case, as Δ (ΔBV3%) in the control cycle 3 corresponding to the second cycle, a Δ (ΔBV%) value measured when water was removed at the U3 was adopted.

次に第３図に示すように制御周期３、４および５の制御周期を３個の制御周期として（ΔＢＶｎ％、ΔＢＶｎ＋１％およびΔＢＶｎ＋２％のｎが３の場合）、前記制御周期１、２および３あるいは前記制御周期２、３および４の制御周期とする場合と同様にして第３制御周期に相当する制御周期５の目標Δ（ΔＢＶ５’％）を算出した後、前記式（ａ）によりＵ５を求めた。この場合第２制御周期に相当する制御周期４のΔ（ΔＢＶ４％）としては、前記Ｕ４で除水した場合に計測したΔ（ΔＢＶ％）値を採用した。
前記第３制御周期に設定する目標Δ（ΔＢＶ％）は患者に負担を強いることなく、かつ所定の血液透析時間内に透析が終了するという観点から透析前に医師等によってあらかじめ設定されるが、この目標Δ（ΔＢＶ％）は各目標Δ（ΔＢＶ％）を結んだ制御線（目標制御線）として設定しても良い。
前記のように継時的に３個の制御周期を設定し、かつ前式（ａ）を利用した制御プログラムの制御を行うことにより血液透析条件を自動的に制御することが可能となった。 Next, as shown in FIG. 3, the control cycles 3, 4 and 5 are set to three control cycles (when ΔBVn%, ΔBVn + 1% and ΔBVn + 2% n is 3), the control cycles 1, 2 and 3 or the target control period 5 corresponding to the third control period (ΔBV5 ′%) is calculated in the same manner as in the case of the control periods 2, 3, and 4, and then U5 is calculated by the above equation (a). Asked. In this case, as the Δ (ΔBV4%) of the control cycle 4 corresponding to the second control cycle, the Δ (ΔBV%) value measured when water was removed at the U4 was adopted.
The target Δ (ΔBV%) set in the third control cycle is set in advance by a doctor or the like before dialysis from the viewpoint that dialysis is completed within a predetermined hemodialysis time without imposing a burden on the patient. This target Δ (ΔBV%) may be set as a control line (target control line) connecting the respective targets Δ (ΔBV%).
As described above, it is possible to automatically control hemodialysis conditions by setting three control cycles over time and controlling the control program using the previous equation (a).

本発明によって、血液透析条件の制御プログラムに初期血液量を必要としないため、制御機構がシンプルであり、誤操作や暴走の危険性が少ない血液透析装置を提供することができた。 According to the present invention, since the initial blood volume is not required for the control program for hemodialysis conditions, it is possible to provide a hemodialysis apparatus with a simple control mechanism and less risk of erroneous operation and runaway.

本発明の血液処理装置の透析開始後第１〜３番目の制御周期を利用した制御態様を説明した図である。It is the figure explaining the control aspect using the 1st-3rd control period after the dialysis start of the blood processing apparatus of this invention. 本発明の血液処理装置の透析開始後第２〜４番目の制御周期を利用した制御態様を説明した図である。It is a figure explaining the control aspect using the 2nd-4th control period after the dialysis start of the blood processing apparatus of this invention. 本発明の血液処理装置の透析開始後第３〜５番目の制御周期を利用した制御態様を説明した図である。It is a figure explaining the control aspect using the 3rd-5th control period after the dialysis start of the blood processing apparatus of this invention.

Explanation of symbols

Ｆ実測値線
Ｇ目標制御線 F Measured value line
G Target control line

Claims

Blood measuring means for measuring blood parameters, working means for performing blood processing, and control means for controlling blood processing of the working means are configured, and the control means sets three or more control cycles continuously. And a hemodialysis apparatus characterized by controlling hemodialysis conditions based on a control program using the following formula (a).
U3 = [U2 × {Δ (ΔBVn%) − Δ (ΔBVn + 2 ′%)} − U1 × {Δ (ΔBVn + 1%) − Δ (ΔBVn + 2 ′%)}] / {Δ (ΔBVn%) − Δ (ΔBVn + 1%) } ... (a)
[In the formula, U1 is the water removal rate in the control cycle n (first control cycle), U2 is the water removal rate in the control cycle n + 1 (second control cycle) next to the control cycle n, and U3 is the next cycle after the control cycle n + 1. It means the target water removal speed in the control cycle n + 2 (third control cycle). Δ (ΔBVn%) is the difference between ΔBVn% at the end of the control cycle n and ΔBVn−1% at the start of the control cycle n, and Δ (ΔBVn + 1%) is ΔBVn + 1% at the end of the control cycle n + 1 and the start point of the control cycle n + 1. The difference between ΔBVn% and Δ (VBn + 2 ′%) means the difference between ΔBVn + 2 ′% targeted in the control cycle n + 2 and ΔBVn + 1% of the start point of the control cycle n + 2. n means an integer of 1 or more.

In the first control cycle after the start of hemodialysis, the Δ (ΔBVn%) value is measured by water removal at the water removal speed U1, and in the second control cycle after the start of hemodialysis, water removal is performed. The Δ (ΔBVn + 1%) value is measured by dehydrating the speed U2, and the third after the start of hemodialysis using these measured Δ (ΔBVn%) value and Δ (ΔBVn + 1%) value and the U1 and U2 values. The hemodialysis apparatus according to claim 1, wherein U3 of the subsequent control cycle is calculated by the equation (a).

The hemodialysis apparatus according to claim 1 or 2 , wherein the control program automatically calculates the water removal rate U3 of the third period based on the following equation (b) instead of the equation (a). .
U3 = Δ (ΔBVn + 2 ′%) / Δ (ΔBVn + 1%) × U2 × k (b)
(Where k is a correction coefficient defined by k = Δ (ΔBVn%) × U2 / Δ (ΔBVn + 1%) × U1. Δ (ΔBVn%), Δ (ΔBVn + 1%) and Δ (ΔBVn + 2 ′%) Is the same as above.)

The hemodialysis apparatus according to any one of claims 1 to 3, wherein each of the control cycles is set to be short so that there is no substantial difference in the patient's PRR.

Hemodialysis apparatus according to any one of claims 1 to 4 .DELTA.BV% is characterized in that it is calculated on the basis of the following formula (d).
ΔBV% = {(Hct at the start of dialysis / Hct at the time of measurement) −1} × 100 (d)
(In the above formula, Hct means hematocrit value)

The hemodialysis apparatus according to any one of claims 1 to 5, wherein the hemodialysis apparatus has a Δ (ΔBVn%) value by water removal at a water removal speed U1 in a first control period after the start of hemodialysis. In the second control period after the start of hemodialysis, Δ (ΔBVn + 1%) value is measured by removing water at the water removal rate U2, and these Δ (ΔBVn%) value and Δ (ΔBVn + 1%) are measured. ) Value and the U1 and U2 values are used to calculate hemodynamic dialysis by calculating U3 of the third and subsequent control cycles after the start of hemodialysis according to the equation (a).