JP3706841B2

JP3706841B2 - Biological data measuring device

Info

Publication number: JP3706841B2
Application number: JP2002113656A
Authority: JP
Inventors: 針次近藤
Original assignee: 株式会社ケーアンドエス
Priority date: 2002-04-16
Filing date: 2002-04-16
Publication date: 2005-10-19
Anticipated expiration: 2022-04-16
Also published as: JP2003305014A

Description

【０００１】
【発明の属する技術分野】
本発明は、生体データ測定装置に関する。
【０００２】
【従来の技術】
従来、血圧値を連続して測定する方法としてはカフと光電センサとを併用するものが知られている。
具体的には、光電センサで計測される光電脈波の相対的な変化量を絶対値化するための手法としてカフが用いられ、測定の初期段階では、光電センサから得られる光電脈波（相対値）とカフから得られる圧脈波（絶対値）とを関連づけるためのキャリブレーションが行われる。
【０００３】
【発明が解決しようとする課題】
上記測定方法の場合、血圧を測定するに先立って、カフにより被験者の動脈の圧迫を行う必要があった。この場合、測定のやり直し等、数度動脈の圧迫を行うと被験者に苦痛を強いることとになり、また、カフによる血圧測定中は安静にしておく必要があるため被験者が幼児又は子供である場合には、測定が容易に出来ないという問題があった。そのため、カフによる予備測定を行うことなく血圧値を測定することが切望されていた。
本発明は上記のような事情に基づいて完成されたものであって、カフによる予備測定を行うことなく血圧値を算出することが出来る生体データ測定装置を提供することを目的とする。
【０００４】
【課題を解決するための手段】
上記の目的を達成するための手段として、請求項１の発明は、被験者の血管へ所定波長の光を照射しこの照射光による透過光あるいは反射光から血流量の変化を光電容積脈波として検出する光電センサを含んだ測定手段と、得られた光電容積脈波を取り込んで演算処理を行うとともに、その一部にメモリ領域が設けられた演算手段と、前記演算手段によって算出された結果を表示する表示手段とからなる生体データ測定装置であって、前記メモリ領域には前記光電容積脈波から前記被験者の血圧値を算出するためのデータ、若しくはこのデータに基づいて算出された演算式が書き込み可能とされており、このデータを計測するための仮想人体モデルは液体を移送可能とする移送管と、この液体を定められた標準心拍時間毎に圧送するための液体給送手段と、前記移送管に発生する液体の圧力を計測する圧力センサと、前記標準心拍時間毎に前記液体の流量を計測するための流量センサと、前記液体の流量の変化を光電容積脈波として検出する前記光電センサとから構成されるとともに、この仮想人体モデルの移送管を径の異なる移送管に変えて計測を行うことで、前記データ、若しくは前記演算式として、前記光電センサにより測定された光電容積脈波の心拍時間あたりの脈波面積と前記流量センサによって計測された流量の絶対値との対応関係が算出された血流量変換データ、若しくはこの血流量変換データに基づく血流量演算式と、前記流量センサによって計測された前記液体の流量の絶対値と前記圧力センサによって計測された圧力の絶対値との対応関係が移送管径毎に算出された参照データ、若しくはこの参照データに基づく血圧演算式とが算出されるとともに、前記演算手段は、前記被験者の血流量の相対的な変化に対応した前記光電容積脈波より心拍時間当たりの脈波面積を算出し、算出された脈波面積を前記人体仮想モデルで計測された血流量変換データ、若しくは血流量演算式に基づいて演算処理することで前記被験者の血流量の絶対値を算出し、その後、この絶対値化された血流量及び前記被験者に対する前記光電容積脈波の周期に基づいて前記被験者の血管径の絶対値を算出し、続いて、前記参照データ若しくは前記血圧演算式のうち、得られた血管径に対応する移送管径の参照データ若しくは血圧演算式を前記メモリ領域から選択し、選択された参照データ若しくは血圧演算式と、絶対値化された前記被験者の血流量に基づいて血圧値を算出するところに特徴を有する。
【０００５】
請求項２の発明は、請求項１に記載のものにおいて、前記測定手段は同一血管の異なる場所に設置された複数の光電センサから構成されるとともに、前記演算手段がこれら光電センサから得られた測定部位毎の測定値を比較することによって、前記被験者の血管のつまりを検出するところに特徴を有する。
請求項３の発明は、請求項１に記載のものにおいて、前記光電センサにより頭蓋骨若しくは橈骨の動脈、又は前腕動脈を含んだ動脈に対し所定波長の光を照射しこの照射光による透過光あるいは反射光によって、前記動脈内の血流量の変化に対応した光電容積脈波を無侵襲で連続して測定するところに特徴を有する。
【０００６】
請求項４の発明は、請求項１に記載のものにおいて、前記測定手段は前記光電センサに加えて、前記被験者の血管の圧力変動を測定可能な圧力センサが設けられるとともに、前記メモリ領域には前記被験者の測定部位に対応した部位の標準血管径が書き込まれることで、前記演算手段は前記標準血管径と前記圧力センサから得られる圧力データとに基づいて前記被験者の血管径を算出するとともに、前記光電センサから得られる前記光電容積脈波に基づいて前記被験者の血液の流速を算出し、更に、これら血管径と流速とに基づいて被験者の血流量を連続して算出するところに特徴を有する。
【０００７】
請求項５の発明は、請求項１又は請求項４に記載のものにおいて、前記測定手段には前記被験者の発汗量、皮膚温を測定可能な発汗・皮膚温測定手段が設けられるとともに、この発汗・皮膚温測定手段及び前記光電センサに基づいてそれぞれ発汗量の測定、皮膚温の測定、及び血流量の算出がなされ、これら発汗量と血流量との関係を示すデータ及び、皮膚温と血流量との関係を示すデータが被験者ごとに前記メモリ領域に記憶されるところに特徴を有する。
【０００８】
請求項６の発明は、請求項５に記載のものにおいて、前記メモリ領域には人の身長、体重、年齢、性別のうち少なくともいずれか一つを含んだ体つきデータと体表面積との関係を表した体表面積変換データが記憶されるとともに、前記演算手段は前記被験者の体つきデータと前記体表面積変換データから前記被験者の体表面積を算出する一方、前記発汗・皮膚温測定手段によって計測された皮膚温の測定値又は前記演算手段によって前記皮膚温と血流量との関係を示すデータに基づいて算出された皮膚温計算値から前記被験者の皮膚温の平均値を算出し、この皮膚温の平均値と前記体表面積とから前記被験者に必要とされる消費熱量を算出するところに特徴を有する。
【０００９】
請求項７の発明は、請求項１ないし請求項６のいずれかに記載のものにおいて、前記光電センサは血管中の酸化ヘモグロビン及び還元ヘモグロビンの双方に対して吸収・反射される波長帯域の光を照射する一方、前記演算手段はその透過光あるいは反射光の光量変化に基づいて両ヘモグロビンの含有量の変化量を算出し、この両ヘモグロビン含有量に基づいて血流量の相対的な変化量を算出するところに特徴を有する。
【００１０】
【発明の作用及び効果】
＜請求項１の発明＞
請求項１の発明によれば、流量センサ、圧力センサを備えた仮想人体モデルでは、液体給送手段により加圧された液体を移送管に流して計測が行われ、その結果、流量（絶対値）と圧力（絶対値）との関係が得られる。このシュミレーションは異なる径（例えば、φ２．０、φ２．５、φ３．０）の移送管毎になされ、その結果が参照データとして演算手段のメモリ領域に書き込まれる。すなわち、移送管径に対応した複数個の参照データが書き込まれる。
また、この計測の際には光電センサによって移送管内の液体の流量を光電容積脈波（相対値）として計測しつつ、一方では流量センサによって流量の絶対量を計測している。これにより光電容積脈波と液体の流量との対応関係、すなわち血流量変換データが得られる。尚、この血流量変換データは移送管毎に測定する必要はない。
【００１１】
一方、被験者に対する測定の際には、光電センサによって被験者の血管に所定波長の光が照射され光電容積脈波（相対値）が検出される。すると、演算手段が被験者から得られた光電容積脈波を、仮想モデルによって得られた血流量変換データに基づいて演算処理を行い、被験者の血流量（絶対値）を算出する。続いて、演算手段は被験者の光電容積脈波の周期から脈拍を算出し、前記した血流量とともに被験者の血管径（絶対値）を算出する。
その後、演算手段は、メモリ領域にある複数の参照データの中から、算出された血管径に対応した参照データを選択するとともに、選択された参照データと血流量（絶対値）とから血圧（絶対値）を算出する。
【００１２】
このように、演算手段のメモリ領域には、予め、流量と圧力との対応関係を表す参照データが移送管の径毎に記憶されている。そのため、光電容積脈波に基づいて算出される血流量及び脈拍から血管径を算出してやれば、被験者の血管径に対応した参照データが得られて、これに基づき血流量から血圧値を算出することが出来る。従って、従来、被験者の個体ばらつきを考慮した場合に必要とされていた測定の初期段階で行われるキャリブレーションを廃止し、光電センサによる測定のみを行えば血圧を測定することが出来る。かくして、被験者に対し苦痛を強いることがなく測定を行うことが出来、また、測定手順の簡素化がなされる。
【００１３】
＜請求項２の発明＞
動脈等の血管が硬化してつまっている際には、その部分では血液の流れが悪くなるため血流量が減少する。
そこで、請求項２の発明によれば、複数の光電センサを同一血管の異なる場所に設置しており、その設置部位毎に光電容積脈波が計測される。続いて、演算手段が測定部位毎に計測された測定値を比較することで血管のつまり、すなわち動脈硬化を検出することが出来る。
【００１４】
＜請求項３の発明＞
従来、頭蓋骨内の血流量を測定する際には、被験者の頭蓋骨に小さな孔を開けてその隙間から音波等を照射して測定を行っていた。請求項３の発明によれば、光電センサによって音波に比べて短い波長の光を照射することが出来るため、無侵襲で頭蓋骨内の動脈の血流量に対応した光電容積脈波を測定すること出来る。
また、光電センサをその他の動脈、例えば、橈骨動脈又は前腕動脈に対し照射すれば、動脈内の血流量の変化に対応した光電容積脈波を測定するとこが出来る。
【００１５】
＜請求項４の発明＞
請求項４の発明によれば、測定手段として光電センサに加えて被験者の血管の圧力変動を測定可能な圧力センサを設けるとともに、メモリ領域に標準血管径、すなわち、測定部位における人の血管径の平均値を書き込んでおく。
ここで、血管の径は経時的に変化するが、血管の拡張・縮小は被験者の血圧値の推移と関連性があることから、圧力センサから得られる圧力データと標準血管径とに基づいて被験者の血管径を算出することが出来る。
また、光電センサから得られる光電容積脈波に基づいて被験者の血液の流速を算出することが出来る。これより、血管径と流速とに基づいて被験者の血流量を算出することが出来る。
【００１６】
＜請求項５の発明＞
請求項５の発明、出願人の知見によれば発汗量と血流量、皮膚温と血流量とはいずれも対応関係があり、発汗量・皮膚温は血流量の変化に追随して推移する。
そのため、発汗量と血流量との関係及び、皮膚温と血流量との関係をメモリ領域に記憶しておけば、例えば、同一の被験者に対し、同じような状況下で測定を行う場合には、演算手段がメモリ領域から被験者の発汗量・皮膚温と血流量との関係を示すデータを選択するとともに、光電センサから得られる光電容積脈波に基づいて血流量を算出する。
これにより、直接発汗量・皮膚温を測定しなくても、血流量と選択されたデータとに基づいて発汗量・皮膚温を算出することが出来る。
【００１７】
＜請求項６の発明＞
請求項６の発明によれば、演算手段のメモリ領域には体つきと体表面積との関係を表した体表面積データが記憶されている。そのため、例えば身長、体重、性別、年齢等が入力されると、演算手段はその場合の体表面積を概算する。また、演算手段は発汗・皮膚温測定手段によって計測された測定値から被験者の皮膚温の平均値を算出し、続いて、体表面積と皮膚温データの平均値とから被験者に必要とされる消費熱量全体を算出することが出来る。
【００１８】
＜請求項７の発明＞
請求項７の発明によれば、光電センサから酸化ヘモグロビン及び還元ヘモグロビンの両ヘモグロビンによって吸収・反射される波長帯域の光を照射し、その透過光あるいは反射光を光電容積脈波として検出してやれば、得られる光電容積脈波の推移から血流量の推移を知ることが出来る。
【００１９】
【発明の実施の形態】
＜第１実施形態＞
本発明の第１実施形態を図１ないし図７によって説明する。
生体データ測定装置は、図１に示すように、被験者５の血流量の変化を光電容積脈波として検出する光電センサ２６を含んだ脈波測定器（本発明の測定手段に相当する）２０と、この脈波測定器２０の出力ラインに接続されて、光電容積脈波を連続して取り込んで演算処理を行うデータ処理手段（本発明の演算手段に相当する）１０と、データ処理手段１０によって算出された結果を表示するモニタ（本発明の表示手段により表示する）３０により構成されている。
【００２０】
データ処理手段１０はＡ／Ｄコンバータ１１、ＣＰＵ１２、メモリ領域１３を備えている。脈波測定器２０で検出された光電容積脈波はＡ／Ｄコンバータ１１を介してディジタル化されＣＰＵ１２に連続的に取り込まれる。すると、ＣＰＵ１２がディジタル化された光電容積脈波をメモリ領域１３に書き込まれた後述する参照データ、血流量変換データに基づいて演算処理することで被験者の最高血圧・最低血圧を心拍毎に算出し、モニタ３０が血圧値及び光電容積脈波の波形を表示する。
【００２１】
図２に示すように、脈波測定器２０はリストバンド２１及び本体部２２とから構成されている。リスバンド２１は、例えば両端部が結合可能となっており被験者５の手首に固定することが出来る。本体部２２は手首に宛われる側が開放した筐体２３に、開口部分を塞ぐ板部材２４を備えている。この板部材２４は筐体２３との間に設けられたばね部材２５によって弾性支持されており、常には被験者５の皮膚側に押圧されている。
【００２２】
この板部材２４には複数の貫通孔が形成されており、これら貫通孔には光電センサ２６が板部材２４の奥側から差し込まれた状態で固定されている。光電センサ２６は投光部２６Ａとして発光ＬＥＤと、受光部２６Ｂとしてのフォトトランジスタとから構成されている。尚、発光ＬＥＤとしては血流量に対応した出力がフォトトランジスタを介して得られるものであればよく、例えば、血液中の酸化ヘモグロビン及び還元ヘモグロビンの双方に対して吸収・反射される波長帯域の光を使用する。この場合には、フォトトランジスタの出力は血液中のヘモグロビンの含有量の変化量に追随して推移するため、得られる出力は血流量の相対的な変化量に対応するものとなる。
また、脈波測定器２０には投光部２６Ａを駆動するための駆動回路（図示せず）、及び受光部２６Ｂの出力信号を処理する受信回路（図示せず）を備えており、得られた光電容積脈波は前記出力ラインを介して前記データ処理手段１０に伝達される。
【００２３】
続いて、光電容積脈波（相対値）から被験者の血流量（絶対値）を算出するための血流量変換データ、及び被験者の血流量（絶対値）から被験者の最高血圧・最低血圧（絶対値）を算出するための参照データについて図３ないし図５を参照して説明する。
参照データ及び血流量変換データは、図３に示す仮想人体モデル４０での計測によって得られる。具体的には、仮想人体モデル４０は液体（模擬血液、すなわち、人の血液と成分が似たものであればよく、例えば、動物の血液等を使用すればよい。）４９が貯められたタンク４１と、液体４９を循環・移送するためのチューブ（本発明の移送管に相当し、人の血管を想定したもの）４２と、このチューブ４２に液体４９を標準心拍時間、例えば０．７５秒（心拍数では８０回／ｍｉｎに相当）毎に圧送するためのポンプ４３（本発明の液体給送手段に相当する）を備えている。更に、チューブ４２の途中には標準心拍時間あたりの液体４９の流量を計測する流量センサ４４、液体４９の流量を光電容積脈波として検出する光電センサ４５及び圧力測定部４６とが設けられている。圧力測定部４６はゴム製の圧力弁４７Ａによって上下２室に仕切られた容器４７と、容器４７の下室側に接続された圧力センサ４８によって構成されるとともに、上室には前記チューブ４２が接続されており前記液体４９が上室内を循環可能とされている。
尚、光電センサ２６と光電センサ４５は同種のものであることが望ましい。
【００２４】
かくして、液体４９が圧送されると圧力弁４７Ａが下方に変位して下室側の圧力が変動し最大となる。この圧力（人体における最高血圧に相当）が圧力センサ４８によって計測される。一方、液体４９が圧送された後には圧力弁４７Ａが上室側へ移動し下室側の圧力が変動し最小となり、この圧力（人体における最低血圧に相当）が圧力センサ４８によって計測される。
また、光電センサ４５、流量センサ４４、圧力センサ４８の出力ラインはそれぞれＡ／Ｄコンバータ１１に接続されている。
【００２５】
以上のようにして構成された仮想人体モデル４０による計測によって、血流量変換データが算出される。具体的には、まず、標準心拍時間当たりの脈波面積（図４の（ａ）参照）Ｓｏが光電センサ４５から得られる光電容積脈波（相対値）に基づいて算出される。更に、標準心拍時間当たりの液体４９流量Ｑｏが流量センサ４４によって算出され、これらの対応関係が血流量変換データ（図４の（ｂ）参照）としてメモリ領域１３に書き込まれる。
尚、この血流量変換データを数式化して血流量演算式として、メモリ領域１３に書き込んでおいてもよい。
【００２６】
また、仮想人体モデル４０では人の血管径のばらつきを考慮するためにチューブ４２径を変えて（例えば、φ２．０、φ２．５、φ３．０等）計測を行い、そこから得られる流量センサ４４の出力と圧力センサ４８の出力、すなわち流量と圧力との対応関係を参照データ（図５参照）としてメモリ領域１３に書き込む。
この参照データについても前記血流量変換データと同様に、数式化して血圧演算式としてメモリ領域１３に書き込んでおいてもよい。
尚、本実施形態では血流量変換データ及び参照データを計測するのに、上記した仮想人体モデル４０を工学的に構成したが、図７に示すように動物実験することにより計測することも出来る。
【００２７】
次に、以上のように構成された生体データ測定装置によって、被験者５の血圧を算出する手順を図６のフローチャートを参照して説明する。
まず、被験者５に対しリストバンド２１を巻き付けて光電センサ２６が被験者５の血管と対応した位置となるように脈波測定器２０をセットする。その後、投光部２６Ａ、受光部２６Ｂによって被験者５の光電容積脈波が連続して測定されるとともに、測定された光電容積脈波はＡ／Ｄコンバータ１１を介してＣＰＵ１２に取り込まれる（ａ工程）。
【００２８】
ＣＰＵ１２では、被験者５の光電脈波容積脈波（相対値）に基づいて、１心拍当たりの脈波面積が算出され、更に、１心拍時間の脈波面積を前記した標準心拍時間当たりに換算する処理が合わせて行われる（ｂ工程）。例えば、１心拍時間をｔ１、標準心拍時間をｔ２とし、１心拍当たりの脈波面積をｓ１とすると、標準心拍時間ｔ２に換算した脈波面積ｓ２は次のようになる。
ｓ２＝ｓ１×ｔ２／ｔ１
以下、この標準心拍時間に換算した脈波面積をＳとする。
この脈波面積Ｓと図４の（ｂ）に示す血流量変換データとから被験者の血流量Ｑ（絶対値）が算出される（ｃ工程）。例えば、被験者５の標準心拍時間当たり脈波面積ＳがＳ１であった場合、被験者の血流量はＱ１となる。また、血流量Ｑの算出とともに被験者５の光電容積脈波の周期に基づいて脈拍も算出される（ｃ工程）。
【００２９】
続いて、算出された血流量Ｑ、脈拍に基づいて被験者５の血管径が血管径算出アルゴリズムから算出される（ｄ工程）。
すると、ＣＰＵ１２はメモリ領域１３に書き込まれている複数の参照データの中から、算出された血管径と対応する参照データを選択する（ｅ工程）。例えば、算出された血管径がφ２．０の場合は図５の（ａ）の参照データが選択される。かくして、参照データが選定されると、ＣＰＵ１２がｃ工程で算出した被験者５の血流量Ｑ（絶対値）と参照データとから被験者５の血圧値Ｐ（絶対値）を算出する（ｆの工程）。例えば、被験者５の血流量Ｑの値がＱ１であった場合には、図５に示すように、被験者５の最大血圧、最小血圧値はそれぞれＰｍａｘ１、Ｐｍｉｎ１となり、その結果がモニタ３０に表示される（ｇの工程）。
尚、上記したフローチャートでは、脈波面積Ｓと血流量変換データとから被験者５の血流量Ｑ（絶対値）を算出し、血流量Ｑ（絶対値）と参照データとから被験者５の血圧値Ｐを算出することとしたが、脈波面積Ｓと血流量演算式とから被験者５の血流量Ｑ（絶対値）を算出し、算出された血流量Ｑ（絶対値）と血圧演算式とから被験者５の血圧値Ｐを算出してもよい。
【００３０】
このように、データ処理手段１０のメモリ領域１３には、予め、流量と圧力との対応関係を表す参照データがチューブ４２径毎に書き込まれている。そのため、光電容積脈波に基づいて血流量Ｑ及び脈拍を算出し、それらから血管径を算出してやれば、被験者５の血管径に対応した参照データが決定される。
その後、被験者５の血流量Ｑと参照データとから被験者５の血圧値Ｐを算出することが出来る。従って、従来、被験者５の個体ばらつきを考慮した場合に必要とされていた測定の初期段階で行われるキャリブレーションを廃止し、光電センサ２６による測定のみを行えば血圧を測定することが出来る。かくして、被験者５に対し苦痛を強いることがなく測定を行うことが出来、また、測定手順の簡素化が図られる。
【００３１】
また、上記した生体データ測定装置は以下のように使用することも出来る。
前記光電センサ２６を複数個（例えば、投光部２６Ａ、受光部２６Ｂとも各４個）設けるとともに、これら光電センサ２６を被験者５の同一血管上の異なる場所に設置しておき、データ処理手段１０によって測定部位毎に血流量を算出する。動脈硬化が起こって血管が詰まっている場合には、その部分で血流量が減少するため、ＣＰＵ１２によって算出された血流量Ｑの比較を行うことで動脈硬化を検出することが出来る。
【００３２】
更に、前記脈波測定器２０のリストバンド２１を人の頭部に巻き付けることが出来るように変更して、光電センサ２６が頭蓋骨に向くようにセットする。この時、光電センサ２６の投光部２６Ａから照射される照射光を所定の波長帯域にあるものを使用すれば照射光が頭蓋骨内に進入し、内部の血管の血流量に対応した光電容積脈波を無侵襲で測定することが出来る。
また、光電センサ２６をその他の動脈、例えば、橈骨動脈又は前腕動脈に対し照射すれば、動脈内の血流量の変化に対応した光電容積脈波を測定するとこが出来る。
【００３３】
更にまた、測定手段として光電センサ２６に加えて、被験者５の血管の圧力変動を測定可能な被験者用圧力センサ（図示せず）を設けることによって、前記した仮想人体モデル４０を使用することなく、被験者５の血流量を算出することが出来る。この場合には、メモリ領域１３に標準血管径、すなわち、測定部位における人の血管径の平均値を予め書き込んでおく。
ここで、血管の径は経時的に変化するが、血管径の拡張・縮小は被験者５の血圧値Ｐの推移と関連性があることから、被験者用圧力センサから得られる圧力データと標準血管径とに基づいて被験者５の血管径値を算出することが出来る。
また、光電センサ２６から得られる光電容積脈波に基づいて被験者５の血液の流速を算出することが出来る。これより、血管径と流速とに基づいて被験者５の血流量を算出することが出来る。
【００３４】
＜第２実施形態＞
次に、本発明の第２実施形態を図８ないし図１０を参照して説明する。
第１実施形態では、測定手段を光電センサ２６を備えた脈波測定器２０により構成するとともに、データ処理手段１０では被験者５の血圧値Ｐを算出したが、第２実施形態では、測定手段として脈波測定器２０に加えて、発汗量測定器５０及び皮膚温検出のための温度センサ６０を備え、被験者５の血圧値Ｐに加えて、発汗量及び皮膚温を計測する。
【００３５】
発汗量測定器５０について説明すると、図９に示すように、本願と同一の出願人による特開平１０−２６２９５８号公報掲載の発汗量測定装置と基本原理を同じくする。すなわち、発汗量測定器５０にはカプセル５１が備えられ、そのカプセル５１に形成した凹所５２の開口５２Ａを、患者の皮膚面で閉塞して取付けられる。そして、カプセル５１の側面には、凹所５２に連通する供給口５３と排出口５４とが設けられ、供給口５３に連なるゴム管５３Ａを介してボンベ（図示せず）から凹所５２内に例えば低湿度窒素ガスが一定流量で供給される。一方、排出口５４に連なるゴム管５４Ａの途中には湿度計（図示せず）が設けられ、排出空気の湿度を測定している。また、このカプセル５１には、温度計と加熱冷却器（例えば、ペルチェ素子）とが内臓されて、凹所５２内の温度を一定に保つように制御されている。そして、発汗量測定器５０の出力ラインもＡ／Ｄコンバータ１１を介してＣＰＵ１２に接続されており、検出された湿度計及び温度計の出力結果が発汗量信号として演算手段に取り込まれて演算され、被験者５の発汗量が得られる。
【００３６】
次に、皮膚温検出のための温度センサ６０は、例えば、熱膨張式、熱電対あるいはサーミスタ式のものを使用すればよく、被験者５の腕などに取り付けて測定を行うことで被験者５の皮膚温を検出可能となっている。皮膚温検出のための温度センサ６０の出力ラインもＡ／Ｄコンバータ１１を介してＣＰＵ１２に接続されており、検出された測定結果は皮膚温検出としてデータ処理手段１０に取り込まれて演算され、被験者５の皮膚温が得られる。
一方、ＣＰＵ１２には、これら発汗量・皮膚温データが取り込まれる間、脈波測定器２０から被験者５の光電容積脈波が取り込まれ、この光電容積脈波と前述した血流量変換データより被験者の血流量Ｑが算出される。
これにより、ＣＰＵ１２は発汗量と血流量Ｑとの対応関係、皮膚温と血流量Ｑとの対応関係をそれぞれ算出し、これを被験者５毎にメモリ領域１３に書き込んでおく（図１０参照）。
この時、測定時の環境（湿度、温度等）等のデータとともに合わせて書き込んでおくことが望ましい。
【００３７】
出願人の知見によれば、発汗量と血流量及び、皮膚温と血流量とはそれぞれ対応関係がある。そのため、既に該当する被験者５の発汗量と血流量及び、皮膚温と血流量との対応関係がメモリ領域１３に書き込まれていれば新たに発汗量測定器５０、及び皮膚温検出のための温度センサ６０によって測定を行わなくても、脈波測定器２０によって光電容積脈波の測定を行えば、メモリ領域１３に書き込まれた発汗量、皮膚温と血流量Ｑとの対応関係に基づいて被験者５の発汗量及び皮膚温を算出することが出来る。
尚、被験者５自身のデータであっても、なるべく、測定日の湿度及び温度等が近いデータを使用することが望ましく、そうすることで誤差となる要因を排斥することが出来正確なデータを得ることが出来る。
【００３８】
また、メモリ領域１３に、次に説明する体表面積変換データを書き込んでくとともに、ＣＰＵ１２によって測定された皮膚温の所定時間当たりの平均値を算出してやれば被験者５に必要とされる体内総消費量を算出すること出来る。体表面積変換データは人の体つきと体表面積との対応関係をまとめたデータであって、例えば、身長、体重、年齢、性別を入力すると、その人の体表面積が算出される。そのため、皮膚温の平均値と体表面積とに基づいて、被験者５の体内総消費量を算出することが出来る。
【００３９】
＜他の実施形態＞
本発明は上記記述及び図面によって説明した実施形態に限定されるものではなく、例えば次のような実施形態も本発明の技術的範囲に含まれ、さらに、下記以外にも要旨を逸脱しない範囲内で種々変更して実施することができる。
【００４０】
（１）第一実施形態では、１心拍当たりの血流量を光電センサ２６によって測定したが、レーザ光及び他の光源あるいは超音波・圧力センサを利用して測定しても良い。
【００４１】
（２）第一実施形態では、動脈硬化を検出する際に、被験者５の血流量を固定式の光電センサ２６によって測定を行ったが、スキャナー式のもので測定してもよい。
【００４２】
（３）第一・二実施形態では、測定対象を人としたが、例えば植物を測定対象とすることが出来る。
【図面の簡単な説明】
【図１】本発明の第一実施形態に係る生体データ測定装置のブロック図
【図２】脈波測定器の断面図
【図３】仮想人体モデルのブロック図
【図４】（ａ）光電脈波の波形図
（ｂ）脈波面積と流量の推移を示すグラフ
【図５】血流量と血圧値の推移を示すグラフ
【図６】最高血圧・最低血圧を算出する手順を示すフローチャート
【図７】動物実験のブロック図
【図８】本発明の第二実施形態に係る生体データ測定装置のブロック図
【図９】発汗量測定器のカプセルの部分破断斜視図
【図１０】（ａ）血流量と発汗量の推移を示すグラフ
（ｂ）皮膚温度と発汗量の推移を示すグラフ
【符号の説明】
１０…データ処理手段（演算手段）
１３…メモリ領域
２０…脈波測定器（測定手段）
２６…光電センサ
３０…モニタ（表示手段）
４０…仮想人体モデル
４２…チューブ（移送管）
４３…ポンプ（液体給送手段）
４４…流量センサ
４５…光電センサ
４８…圧力センサ
４９…液体
５０…発汗量測定器（発汗・皮膚温測定手段）
６０…皮膚温検出のための温度センサ（発汗・皮膚温測定手段）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a biological data measuring apparatus.
[0002]
[Prior art]
Conventionally, as a method for continuously measuring a blood pressure value, a method using a cuff and a photoelectric sensor in combination is known.
Specifically, a cuff is used as a method for making an absolute value of the relative change amount of the photoelectric pulse wave measured by the photoelectric sensor, and at the initial stage of measurement, the photoelectric pulse wave (relative value) obtained from the photoelectric sensor is used. Value) and a pressure pulse wave (absolute value) obtained from the cuff are calibrated.
[0003]
[Problems to be solved by the invention]
In the case of the above measurement method, it was necessary to compress the subject's artery with the cuff prior to measuring the blood pressure. In this case, if the artery is compressed several times, such as redoing the measurement, it will be painful to the subject, and if the subject is an infant or a child because it is necessary to keep quiet during cuff blood pressure measurement However, there was a problem that measurement could not be performed easily. Therefore, it has been anxious to measure a blood pressure value without performing a preliminary measurement with a cuff.
The present invention has been completed based on the above situation, and an object of the present invention is to provide a biological data measuring apparatus capable of calculating a blood pressure value without performing preliminary measurement with a cuff.
[0004]
[Means for Solving the Problems]
As means for achieving the above object, the invention of claim 1 irradiates a blood vessel of a subject with light of a predetermined wavelength, and detects a change in blood flow as a photoelectric volume pulse wave from transmitted light or reflected light by the irradiated light. Measurement means including a photoelectric sensor that performs the calculation processing by taking in the obtained photoelectric volumetric pulse wave, a calculation means provided with a memory area in a part thereof, and a result calculated by the calculation means are displayed. A biometric data measuring device comprising display means for performing data writing for calculating a blood pressure value of the subject from the photoelectric volume pulse wave, or an arithmetic expression calculated based on the data is written in the memory area The virtual human body model for measuring this data includes a transfer tube that can transfer a liquid, and a liquid for pumping this liquid at a predetermined standard heartbeat time. A feeding means; a pressure sensor for measuring the pressure of the liquid generated in the transfer pipe; a flow rate sensor for measuring the flow rate of the liquid at each standard heartbeat time; It is composed of the photoelectric sensor that detects as a wave, and is measured by the photoelectric sensor as the data or the arithmetic expression by performing measurement by changing the transfer pipe of the virtual human body model to a transfer pipe having a different diameter. Photoelectric volumetric pulse wave Pulse wave area per heartbeat time Blood flow conversion data in which the correspondence between the flow rate and the absolute value of the flow measured by the flow sensor is calculated, or a blood flow calculation formula based on the blood flow conversion data, and the flow rate of the liquid measured by the flow sensor The reference data in which the correspondence between the absolute value of the pressure and the absolute value of the pressure measured by the pressure sensor is calculated for each transfer pipe diameter, or the blood pressure calculation formula based on the reference data is calculated, and the calculation means Is based on the photoelectric volumetric pulse wave corresponding to the relative change in blood flow of the subject. Calculate the pulse wave area per heartbeat time and calculate the calculated pulse wave area Is calculated based on blood flow conversion data measured by the human body virtual model or a blood flow calculation formula, and then the absolute value of the blood flow of the subject is calculated. Calculate the absolute value of the blood vessel diameter of the subject based on the period of the photoelectric volume pulse wave for the subject, and subsequently transfer tube diameter corresponding to the obtained blood vessel diameter in the reference data or the blood pressure calculation formula The reference data or blood pressure calculation formula is selected from the memory area, and the blood pressure value is calculated based on the selected reference data or blood pressure calculation formula and the blood flow volume of the subject converted into an absolute value.
[0005]
According to a second aspect of the present invention, in the method according to the first aspect, the measuring means is composed of a plurality of photoelectric sensors installed at different locations in the same blood vessel, and the arithmetic means is obtained from these photoelectric sensors. It is characterized in that the clogging of the blood vessel of the subject is detected by comparing the measurement values for each measurement site.
According to a third aspect of the present invention, the photoelectric sensor according to the first aspect irradiates light having a predetermined wavelength to an artery including a skull or a radial artery or a forearm artery by the photoelectric sensor, and transmits or reflects light by the irradiation light. It is characterized in that a photoelectric volume pulse wave corresponding to a change in blood flow in the artery is continuously measured non-invasively with light.
[0006]
According to a fourth aspect of the present invention, in the apparatus according to the first aspect, in addition to the photoelectric sensor, the measuring means is provided with a pressure sensor capable of measuring pressure fluctuations in the blood vessel of the subject, and the memory area By writing the standard blood vessel diameter of the site corresponding to the measurement site of the subject, the calculation means calculates the blood vessel diameter of the subject based on the standard blood vessel diameter and pressure data obtained from the pressure sensor, The flow rate of the subject's blood is calculated based on the photoelectric volume pulse wave obtained from the photoelectric sensor, and the subject's blood flow is continuously calculated based on the blood vessel diameter and the flow rate. .
[0007]
According to a fifth aspect of the present invention, in the apparatus according to the first or fourth aspect, the measuring means is provided with a sweating / skin temperature measuring means capable of measuring a sweating amount and a skin temperature of the subject.・ Sweating volume measurement, skin temperature measurement, and blood flow volume are calculated based on the skin temperature measuring means and the photoelectric sensor, respectively, and data indicating the relationship between the sweat volume and blood flow volume, and the skin temperature and blood flow volume. It is characterized in that data indicating the relationship between and is stored in the memory area for each subject.
[0008]
The invention according to claim 6 is the memory device according to claim 5, wherein the memory area represents a relationship between body data including at least one of height, weight, age, and gender of a person and a body surface area. Body surface area conversion data is stored, and the calculation means calculates the body surface area of the subject from the body data of the subject and the body surface area conversion data, while the skin temperature measured by the sweating / skin temperature measurement means. The average value of the skin temperature of the subject is calculated from the measured temperature value or the calculated skin temperature value based on the data indicating the relationship between the skin temperature and the blood flow rate by the calculation means, and the average value of the skin temperature and It is characterized in that the heat consumption required for the subject is calculated from the body surface area.
[0009]
A seventh aspect of the present invention provides the method according to any one of the first to sixth aspects, wherein the photoelectric sensor emits light in a wavelength band that is absorbed and reflected by both oxyhemoglobin and reduced hemoglobin in a blood vessel. On the other hand, the calculation means calculates the change amount of both hemoglobin contents based on the change in the amount of transmitted light or reflected light, and calculates the relative change amount of the blood flow based on the both hemoglobin contents. It has a feature.
[0010]
[Action and effect of the invention]
<Invention of Claim 1>
According to the first aspect of the present invention, in the virtual human body model including the flow rate sensor and the pressure sensor, the measurement is performed by flowing the liquid pressurized by the liquid feeding means to the transfer pipe. As a result, the flow rate (absolute value) ) And pressure (absolute value). This simulation is performed for each transfer pipe having a different diameter (for example, φ2.0, φ2.5, φ3.0), and the result is written as reference data in the memory area of the calculation means. That is, a plurality of reference data corresponding to the transfer pipe diameter is written.
In this measurement, the flow rate of the liquid in the transfer pipe is measured as a photoelectric volume pulse wave (relative value) by the photoelectric sensor, while the absolute amount of the flow rate is measured by the flow rate sensor. Thereby, the correspondence between the photoelectric volume pulse wave and the liquid flow rate, that is, blood flow rate conversion data is obtained. This blood flow conversion data need not be measured for each transfer tube.
[0011]
On the other hand, when measuring a subject, light of a predetermined wavelength is irradiated on the blood vessel of the subject by a photoelectric sensor, and a photoelectric volume pulse wave (relative value) is detected. Then, the calculation means performs a calculation process on the photoelectric volume pulse wave obtained from the subject based on the blood flow rate conversion data obtained by the virtual model, and calculates the blood flow rate (absolute value) of the subject. Subsequently, the computing means calculates the pulse from the period of the photoelectric volume pulse wave of the subject, and calculates the blood vessel diameter (absolute value) of the subject together with the blood flow described above.
Thereafter, the calculation means selects reference data corresponding to the calculated blood vessel diameter from the plurality of reference data in the memory area, and calculates blood pressure (absolute value) from the selected reference data and blood flow volume (absolute value). Value).
[0012]
Thus, the reference data indicating the correspondence between the flow rate and the pressure is stored in advance in the memory area of the computing unit for each diameter of the transfer pipe. Therefore, if the blood vessel diameter is calculated from the blood flow volume and pulse calculated based on the photoelectric volumetric pulse wave, reference data corresponding to the blood vessel diameter of the subject can be obtained, and the blood pressure value is calculated from the blood flow volume based on this. I can do it. Therefore, it is possible to measure the blood pressure by eliminating the calibration that is conventionally performed at the initial stage of measurement, which has been required when individual variations of subjects are taken into consideration, and performing only measurement using a photoelectric sensor. Thus, the measurement can be performed without causing pain to the subject, and the measurement procedure is simplified.
[0013]
<Invention of Claim 2>
When a blood vessel such as an artery is hardened and clogged, the blood flow deteriorates at that portion, and the blood flow rate decreases.
Therefore, according to the invention of claim 2, a plurality of photoelectric sensors are installed at different locations in the same blood vessel, and a photoelectric volume pulse wave is measured for each installation site. Subsequently, the blood vessel, that is, arteriosclerosis, can be detected by the measurement means comparing the measurement values measured for each measurement site.
[0014]
<Invention of Claim 3>
Conventionally, when measuring the blood flow in the skull, a small hole is made in the skull of the subject, and the sound wave or the like is irradiated through the gap. According to the invention of claim 3, since the photoelectric sensor can irradiate light having a wavelength shorter than that of the sound wave, the photoelectric volume pulse wave corresponding to the blood flow of the artery in the skull can be measured non-invasively. .
Further, if the photoelectric sensor is irradiated to other arteries, for example, the radial artery or the forearm artery, the photoelectric volume pulse wave corresponding to the change in blood flow in the artery can be measured.
[0015]
<Invention of Claim 4>
According to the invention of claim 4, in addition to the photoelectric sensor as a measuring means, a pressure sensor capable of measuring the blood pressure fluctuation of the subject's blood vessel is provided, and the standard blood vessel diameter in the memory region, that is, the blood vessel diameter of the person at the measurement site Write down the average value.
Here, the diameter of the blood vessel changes over time, but since the expansion / contraction of the blood vessel is related to the change in the blood pressure value of the subject, the subject is based on the pressure data obtained from the pressure sensor and the standard blood vessel diameter. The blood vessel diameter can be calculated.
Further, the blood flow velocity of the subject can be calculated based on the photoelectric volume pulse wave obtained from the photoelectric sensor. Thus, the blood flow volume of the subject can be calculated based on the blood vessel diameter and the flow velocity.
[0016]
<Invention of Claim 5>
According to the invention of claim 5 and the applicant's knowledge, the amount of perspiration and blood flow, the skin temperature and the blood flow have a corresponding relationship, and the amount of perspiration and skin temperature changes following the change in blood flow.
Therefore, if the relationship between the sweating volume and the blood flow volume and the relationship between the skin temperature and the blood flow volume are stored in the memory area, for example, when performing the measurement under the same situation for the same subject The calculation means selects data indicating the relationship between the subject's sweating amount / skin temperature and blood flow volume from the memory area, and calculates the blood flow volume based on the photoelectric volume pulse wave obtained from the photoelectric sensor.
Accordingly, the sweating amount / skin temperature can be calculated based on the blood flow rate and the selected data without directly measuring the sweating amount / skin temperature.
[0017]
<Invention of Claim 6>
According to the sixth aspect of the present invention, body surface area data representing the relationship between body attachment and body surface area is stored in the memory area of the computing means. Therefore, for example, when height, weight, sex, age, etc. are input, the computing means approximates the body surface area in that case. In addition, the calculation means calculates the average value of the subject's skin temperature from the measurement value measured by the sweating / skin temperature measurement means, and then the consumption required for the subject from the body surface area and the average value of the skin temperature data. The total amount of heat can be calculated.
[0018]
<Invention of Claim 7>
According to the invention of claim 7, if the photoelectric sensor emits light in a wavelength band that is absorbed and reflected by both hemoglobins of oxyhemoglobin and reduced hemoglobin, and the transmitted light or reflected light is detected as a photoelectric volume pulse wave, The transition of the blood flow volume can be known from the transition of the photoelectric volume pulse wave obtained.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the biological data measuring apparatus includes a pulse wave measuring device (corresponding to the measuring means of the present invention) 20 including a photoelectric sensor 26 that detects a change in blood flow of the subject 5 as a photoelectric volume pulse wave. The data processing means (corresponding to the computing means of the present invention) 10 connected to the output line of the pulse wave measuring device 20 and continuously taking photoelectric volume pulse waves to perform the arithmetic processing, and the data processing means 10 The monitor 30 (displayed by the display means of the present invention) that displays the calculated result is configured.
[0020]
The data processing means 10 includes an A / D converter 11, a CPU 12, and a memory area 13. The photoelectric volume pulse wave detected by the pulse wave measuring device 20 is digitized via the A / D converter 11 and continuously taken into the CPU 12. Then, the CPU 12 calculates the subject's systolic blood pressure and systolic blood pressure for each heartbeat by performing arithmetic processing on the digitized photoelectric volume pulse wave based on reference data and blood flow conversion data described later written in the memory area 13. The monitor 30 displays the blood pressure value and the waveform of the photoelectric volume pulse wave.
[0021]
As shown in FIG. 2, the pulse wave measuring device 20 includes a wristband 21 and a main body 22. For example, the squirrel band 21 is connectable at both ends, and can be fixed to the wrist of the subject 5. The main body 22 includes a plate member 24 that closes an opening portion in a housing 23 that is open on the side addressed to the wrist. The plate member 24 is elastically supported by a spring member 25 provided between the plate member 24 and the plate member 24 and is always pressed against the skin side of the subject 5.
[0022]
A plurality of through holes are formed in the plate member 24, and the photoelectric sensor 26 is fixed in the through holes inserted from the back side of the plate member 24. The photoelectric sensor 26 includes a light emitting LED as the light projecting unit 26A and a phototransistor as the light receiving unit 26B. The light emitting LED may be any LED that can obtain an output corresponding to the blood flow through a phototransistor. For example, light in a wavelength band that is absorbed and reflected by both oxyhemoglobin and reduced hemoglobin in blood. Is used. In this case, the output of the phototransistor changes following the change in the content of hemoglobin in the blood, and thus the output obtained corresponds to the relative change in the blood flow.
Further, the pulse wave measuring instrument 20 includes a drive circuit (not shown) for driving the light projecting unit 26A and a receiving circuit (not shown) for processing the output signal of the light receiving unit 26B. The photoelectric volume pulse wave is transmitted to the data processing means 10 through the output line.
[0023]
Subsequently, blood flow conversion data for calculating the blood flow (absolute value) of the subject from the photoelectric volume pulse wave (relative value), and the highest blood pressure and the lowest blood pressure (absolute value) of the subject from the blood flow (absolute value) of the subject ) Will be described with reference to FIGS. 3 to 5. FIG.
The reference data and the blood flow rate conversion data are obtained by measurement with the virtual human body model 40 shown in FIG. Specifically, the virtual human body model 40 is a tank in which a liquid (mock blood, that is, a component similar to human blood, for example, animal blood or the like) 49 is stored. 41, a tube 42 for circulating / transferring the liquid 49 (corresponding to the transfer pipe of the present invention, assuming a human blood vessel) 42, and the liquid 49 is supplied to the tube 42 with a standard heartbeat time, for example, 0.75 seconds. A pump 43 (corresponding to the liquid feeding means of the present invention) for pumping at every heart rate (equivalent to 80 times / min in heart rate) is provided. Further, a flow sensor 44 that measures the flow rate of the liquid 49 per standard heartbeat time, a photoelectric sensor 45 that detects the flow rate of the liquid 49 as a photoelectric volume pulse wave, and a pressure measurement unit 46 are provided in the middle of the tube 42. . The pressure measuring unit 46 includes a container 47 partitioned into two upper and lower chambers by a rubber pressure valve 47A and a pressure sensor 48 connected to the lower chamber side of the container 47, and the tube 42 is disposed in the upper chamber. It is connected so that the liquid 49 can circulate in the upper chamber.
Note that the photoelectric sensor 26 and the photoelectric sensor 45 are desirably of the same type.
[0024]
Thus, when the liquid 49 is pumped, the pressure valve 47A is displaced downward, and the pressure on the lower chamber side fluctuates and becomes maximum. This pressure (corresponding to the maximum blood pressure in the human body) is measured by the pressure sensor 48. On the other hand, after the liquid 49 is pumped, the pressure valve 47A moves to the upper chamber side, the pressure on the lower chamber side fluctuates and becomes the minimum, and this pressure (corresponding to the lowest blood pressure in the human body) is measured by the pressure sensor 48.
The output lines of the photoelectric sensor 45, the flow sensor 44, and the pressure sensor 48 are connected to the A / D converter 11, respectively.
[0025]
Blood flow conversion data is calculated by measurement using the virtual human body model 40 configured as described above. Specifically, first, the pulse wave area per standard heartbeat time (see FIG. 4A) So is calculated based on the photoelectric volume pulse wave (relative value) obtained from the photoelectric sensor 45. Further, the fluid 49 flow rate Qo per standard heartbeat time is calculated by the flow rate sensor 44, and the corresponding relationship is written in the memory area 13 as blood flow rate conversion data (see FIG. 4B).
The blood flow conversion data may be converted into a mathematical formula and written in the memory area 13 as a blood flow calculation formula.
[0026]
In the virtual human body model 40, the tube 42 diameter is changed (for example, φ2.0, φ2.5, φ3.0, etc.) in order to take into account variations in the blood vessel diameter of a person, and a flow rate sensor obtained therefrom is used. The correspondence between the output 44 and the output of the pressure sensor 48, that is, the flow rate and the pressure is written in the memory area 13 as reference data (see FIG. 5).
As with the blood flow conversion data, this reference data may be expressed as a formula and written in the memory area 13 as a blood pressure calculation formula.
In the present embodiment, the above-described virtual human body model 40 is engineered to measure blood flow conversion data and reference data. However, it can also be measured by animal experiments as shown in FIG.
[0027]
Next, the procedure for calculating the blood pressure of the subject 5 using the biological data measuring apparatus configured as described above will be described with reference to the flowchart of FIG.
First, the wristband 21 is wound around the subject 5 and the pulse wave measuring device 20 is set so that the photoelectric sensor 26 is in a position corresponding to the blood vessel of the subject 5. Thereafter, the photoelectric volume pulse wave of the subject 5 is continuously measured by the light projecting unit 26A and the light receiving unit 26B, and the measured photoelectric volume pulse wave is taken into the CPU 12 via the A / D converter 11 (step a). ).
[0028]
The CPU 12 calculates the pulse wave area per heart beat based on the photoelectric pulse volume pulse wave (relative value) of the subject 5, and further converts the pulse wave area per heart beat time per the above-mentioned standard heart beat time. Processing is performed together (step b). For example, assuming that one heartbeat time is t1, the standard heartbeat time is t2, and the pulse wave area per heartbeat is s1, the pulse wave area s2 converted to the standard heartbeat time t2 is as follows.
s2 = s1 × t2 / t1
Hereinafter, the pulse wave area converted to the standard heartbeat time is represented by S.
A blood flow Q (absolute value) of the subject is calculated from the pulse wave area S and the blood flow conversion data shown in FIG. 4B (step c). For example, when the pulse wave area S per standard heartbeat time of the subject 5 is S1, the blood flow rate of the subject is Q1. In addition, the pulse is calculated based on the period of the photoelectric volume pulse wave of the subject 5 together with the calculation of the blood flow rate Q (step c).
[0029]
Subsequently, the blood vessel diameter of the subject 5 is calculated from the blood vessel diameter calculation algorithm based on the calculated blood flow volume Q and pulse (step d).
Then, the CPU 12 selects reference data corresponding to the calculated blood vessel diameter from the plurality of reference data written in the memory area 13 (step e). For example, when the calculated blood vessel diameter is φ2.0, the reference data in FIG. 5A is selected. Thus, when the reference data is selected, the CPU 12 calculates the blood pressure value P (absolute value) of the subject 5 from the blood flow rate Q (absolute value) of the subject 5 calculated in step c and the reference data (step f). . For example, when the value of the blood flow Q of the subject 5 is Q1, the maximum blood pressure and minimum blood pressure values of the subject 5 are Pmax1 and Pmin1, respectively, as shown in FIG. (Step g).
In the above flowchart, the blood flow volume Q (absolute value) of the subject 5 is calculated from the pulse wave area S and the blood flow conversion data, and the blood pressure value P of the subject 5 is calculated from the blood flow volume Q (absolute value) and the reference data. The blood flow rate Q (absolute value) of the subject 5 is calculated from the pulse wave area S and the blood flow calculation formula, and the subject is calculated from the calculated blood flow Q (absolute value) and the blood pressure calculation formula. A blood pressure value P of 5 may be calculated.
[0030]
Thus, the reference data indicating the correspondence between the flow rate and the pressure is written in advance in the memory area 13 of the data processing means 10 for each tube 42 diameter. Therefore, if the blood flow volume Q and the pulse are calculated based on the photoelectric volume pulse wave, and the blood vessel diameter is calculated therefrom, the reference data corresponding to the blood vessel diameter of the subject 5 is determined.
Thereafter, the blood pressure value P of the subject 5 can be calculated from the blood flow rate Q of the subject 5 and the reference data. Accordingly, the blood pressure can be measured by eliminating the calibration performed at the initial stage of the measurement, which has been conventionally required when the individual variation of the subject 5 is taken into consideration, and performing only the measurement by the photoelectric sensor 26. Thus, measurement can be performed without causing pain to the subject 5, and the measurement procedure can be simplified.
[0031]
Moreover, the above-described biological data measuring device can also be used as follows.
A plurality of the photoelectric sensors 26 (for example, four for each of the light projecting unit 26A and the light receiving unit 26B) are provided, and these photoelectric sensors 26 are installed in different locations on the same blood vessel of the subject 5 to thereby process the data processing means 10. To calculate the blood flow for each measurement site. When arteriosclerosis occurs and the blood vessel is clogged, the blood flow volume decreases at that portion, so that the arteriosclerosis can be detected by comparing the blood flow volume Q calculated by the CPU 12.
[0032]
Further, the wristband 21 of the pulse wave measuring device 20 is changed so as to be wound around a human head, and the photoelectric sensor 26 is set so as to face the skull. At this time, if the irradiation light irradiated from the light projecting unit 26A of the photoelectric sensor 26 is in a predetermined wavelength band, the irradiation light enters the skull, and the photoelectric volume pulse corresponding to the blood flow of the internal blood vessel. Waves can be measured non-invasively.
Moreover, if the photoelectric sensor 26 is irradiated to other arteries, for example, the radial artery or the forearm artery, a photoelectric volume pulse wave corresponding to a change in blood flow in the artery can be measured.
[0033]
Furthermore, in addition to the photoelectric sensor 26 as a measuring means, by providing a subject pressure sensor (not shown) that can measure the blood pressure fluctuation of the subject 5, without using the virtual human body model 40 described above, The blood flow rate of the subject 5 can be calculated. In this case, the standard blood vessel diameter, that is, the average value of the human blood vessel diameter at the measurement site is written in the memory area 13 in advance.
Here, although the diameter of the blood vessel changes with time, since the expansion / reduction of the blood vessel diameter is related to the transition of the blood pressure value P of the subject 5, the pressure data obtained from the subject pressure sensor and the standard blood vessel diameter Based on the above, the blood vessel diameter value of the subject 5 can be calculated.
Further, the blood flow velocity of the subject 5 can be calculated based on the photoelectric volume pulse wave obtained from the photoelectric sensor 26. Thus, the blood flow volume of the subject 5 can be calculated based on the blood vessel diameter and the flow velocity.
[0034]
Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS.
In the first embodiment, the measurement means is constituted by the pulse wave measuring device 20 including the photoelectric sensor 26, and the blood pressure value P of the subject 5 is calculated by the data processing means 10, but in the second embodiment, as the measurement means, In addition to the pulse wave measuring device 20, a sweating amount measuring device 50 and a temperature sensor 60 for detecting skin temperature are provided, and in addition to the blood pressure value P of the subject 5, the sweating amount and skin temperature are measured.
[0035]
The sweating amount measuring device 50 will be described. As shown in FIG. 9, the basic principle is the same as that of the sweating amount measuring apparatus disclosed in Japanese Patent Laid-Open No. 10-262958 by the same applicant as the present application. That is, the sweating amount measuring device 50 is provided with a capsule 51, and the opening 52A of the recess 52 formed in the capsule 51 is closed and attached to the skin surface of the patient. A supply port 53 and a discharge port 54 communicating with the recess 52 are provided on the side surface of the capsule 51, and a cylinder (not shown) is connected to the recess 52 through a rubber tube 53 </ b> A connected to the supply port 53. For example, low humidity nitrogen gas is supplied at a constant flow rate. On the other hand, a hygrometer (not shown) is provided in the middle of the rubber tube 54A connected to the discharge port 54 to measure the humidity of the discharged air. The capsule 51 includes a thermometer and a heating / cooling device (for example, a Peltier element), and is controlled so as to keep the temperature in the recess 52 constant. The output line of the sweating amount measuring device 50 is also connected to the CPU 12 via the A / D converter 11, and the detected output results of the hygrometer and the thermometer are taken into the calculation means as the sweating amount signal and calculated. The amount of sweat of the subject 5 is obtained.
[0036]
Next, as the temperature sensor 60 for detecting the skin temperature, for example, a thermal expansion type, a thermocouple, or a thermistor type may be used, and the skin of the subject 5 is measured by attaching to the arm of the subject 5 and performing the measurement. The temperature can be detected. The output line of the temperature sensor 60 for detecting the skin temperature is also connected to the CPU 12 via the A / D converter 11, and the detected measurement result is taken into the data processing means 10 as the skin temperature detection and calculated. A skin temperature of 5 is obtained.
On the other hand, the CPU 12 captures the photoelectric volume pulse wave of the subject 5 from the pulse wave measuring device 20 while the sweat volume / skin temperature data is captured. A blood flow rate Q is calculated.
Thereby, the CPU 12 calculates the correspondence between the sweating amount and the blood flow Q and the correspondence between the skin temperature and the blood flow Q, respectively, and writes them in the memory area 13 for each subject 5 (see FIG. 10).
At this time, it is desirable to write together with data such as environment (humidity, temperature, etc.) at the time of measurement.
[0037]
According to the applicant's knowledge, there is a correspondence relationship between the amount of perspiration and blood flow, and the skin temperature and blood flow. Therefore, if the corresponding relationship between the perspiration amount and the blood flow rate of the subject 5 and the skin temperature and the blood flow rate are already written in the memory area 13, the perspiration amount measuring device 50 and the temperature for detecting the skin temperature are newly added. Even if the measurement is not performed by the sensor 60, if the photoelectric volume pulse wave is measured by the pulse wave measuring device 20, the subject is based on the correspondence between the perspiration amount, the skin temperature, and the blood flow rate Q written in the memory area 13. 5 sweat volume and skin temperature can be calculated.
Even if it is the data of the subject 5 itself, it is desirable to use data that is close to the humidity, temperature, etc. of the measurement date as much as possible. By doing so, it is possible to eliminate the factors causing the error and obtain accurate data. I can do it.
[0038]
Further, the body surface area conversion data described below is written in the memory area 13 and the average amount of skin temperature measured by the CPU 12 per predetermined time is calculated, the total body consumption required for the subject 5 Can be calculated. The body surface area conversion data is data that summarizes the correspondence between a person's body and the body surface area. For example, when the height, weight, age, and sex are input, the body surface area of the person is calculated. Therefore, the total consumption of the subject 5 in the body can be calculated based on the average value of the skin temperature and the body surface area.
[0039]
<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.
[0040]
(1) In the first embodiment, the blood flow rate per one heartbeat is measured by the photoelectric sensor 26, but may be measured by using laser light and other light sources or ultrasonic / pressure sensors.
[0041]
(2) In the first embodiment, when the arteriosclerosis is detected, the blood flow rate of the subject 5 is measured by the fixed photoelectric sensor 26, but may be measured by a scanner type.
[0042]
(3) In the first and second embodiments, the measurement target is a person, but, for example, a plant can be the measurement target.
[Brief description of the drawings]
FIG. 1 is a block diagram of a biological data measuring apparatus according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of a pulse wave measuring device
FIG. 3 is a block diagram of a virtual human body model
[Fig. 4] (a) Waveform diagram of photoelectric pulse wave.
(B) Graph showing changes in pulse wave area and flow rate
FIG. 5 is a graph showing changes in blood flow and blood pressure values.
FIG. 6 is a flowchart showing a procedure for calculating a systolic blood pressure and a systolic blood pressure.
Fig. 7 Block diagram of animal experiments
FIG. 8 is a block diagram of a biological data measuring apparatus according to the second embodiment of the present invention.
FIG. 9 is a partially broken perspective view of a capsule of a sweating amount measuring device.
FIG. 10A is a graph showing changes in blood flow and sweating.
(B) Graph showing changes in skin temperature and sweating amount
[Explanation of symbols]
10: Data processing means (calculation means)
13 ... Memory area
20 ... Pulse wave measuring device (measuring means)
26 ... Photoelectric sensor
30 ... Monitor (display means)
40 ... Virtual human body model
42 ... Tube (transfer pipe)
43 ... Pump (liquid feeding means)
44 ... Flow sensor
45 ... Photoelectric sensor
48 ... Pressure sensor
49 ... Liquid
50 ... Sweating meter (Sweating / skin temperature measuring means)
60 ... Temperature sensor for detecting skin temperature (perspiration and skin temperature measuring means)

Claims

A measuring means including a photoelectric sensor that irradiates a blood vessel of a subject with a predetermined wavelength and detects a change in blood flow as a photoelectric volume pulse wave from transmitted light or reflected light by the irradiated light;
Computation processing that takes in the obtained photoelectric volume pulse wave and performs a calculation process, a memory area provided in a part thereof,
A biological data measuring device comprising display means for displaying the result calculated by the computing means,
In the memory area, data for calculating the blood pressure value of the subject from the photoelectric volume pulse wave, or an arithmetic expression calculated based on the data can be written, and a virtual for measuring this data can be written. The human body model has a transfer pipe that can transfer liquid,
Liquid feeding means for pumping this liquid at a predetermined standard heartbeat time;
A pressure sensor for measuring the pressure of the liquid generated in the transfer pipe;
A flow sensor for measuring the flow rate of the liquid at each standard heartbeat time;
It is composed of the photoelectric sensor that detects a change in the flow rate of the liquid as a photoelectric volume pulse wave, and by changing the transfer pipe of this virtual human body model to a transfer pipe having a different diameter,
Blood flow volume in which the correspondence relationship between the pulse wave area per heartbeat time of the photoelectric volume pulse wave measured by the photoelectric sensor and the absolute value of the flow rate measured by the flow sensor is calculated as the data or the arithmetic expression Conversion data or blood flow calculation formula based on this blood flow conversion data,
Reference data in which the correspondence between the absolute value of the flow rate of the liquid measured by the flow sensor and the absolute value of the pressure measured by the pressure sensor is calculated for each transfer pipe diameter, or blood pressure calculation based on this reference data And the formula is calculated,
The calculation means calculates a pulse wave area per heartbeat time from the photoelectric volume pulse wave corresponding to a relative change in the blood flow of the subject, and the calculated pulse wave area is measured by the human body virtual model. Calculate the absolute value of the blood flow of the subject by performing a calculation process based on the blood flow conversion data or the blood flow calculation formula,
Thereafter, the absolute value of the blood vessel diameter of the subject is calculated based on the blood flow volume converted into the absolute value and the period of the photoelectric volume pulse wave for the subject,
Subsequently, out of the reference data or the blood pressure calculation formula, the reference data or blood pressure calculation formula of the transfer tube diameter corresponding to the obtained blood vessel diameter is selected from the memory area, and the selected reference data or blood pressure calculation formula is selected. A biological data measuring device that calculates a blood pressure value based on an absolute value of the blood flow of the subject.

The measuring means is composed of a plurality of photoelectric sensors installed at different locations in the same blood vessel,
2. The biological data measuring apparatus according to claim 1, wherein the calculation means detects clogging of the blood vessel of the subject by comparing the measured values obtained from the photoelectric sensors for each measurement site.

A photoelectric volume corresponding to a change in blood flow in the artery by irradiating light of a predetermined wavelength to an artery including a skull or a radial artery or a forearm artery by the photoelectric sensor and transmitting light or reflected light by the irradiated light 2. The biological data measuring apparatus according to claim 1, wherein the pulse wave is continuously measured in a non-invasive manner.

In addition to the photoelectric sensor, the measuring means is provided with a pressure sensor capable of measuring pressure fluctuations in the blood vessels of the subject, and a standard blood vessel diameter corresponding to the measurement site of the subject is written in the memory area With that
The calculation means calculates the blood vessel diameter of the subject based on the standard blood vessel diameter and pressure data obtained from the pressure sensor,
The blood flow rate of the subject is calculated based on the photoelectric volume pulse wave obtained from the photoelectric sensor, and the blood flow rate of the subject is continuously calculated based on the blood vessel diameter and the flow rate. The biological data measuring device according to claim 1.

The measuring means is provided with sweating / skin temperature measuring means capable of measuring the amount of sweat of the subject and the skin temperature,
Based on this sweating / skin temperature measuring means and the photoelectric sensor, the amount of sweating, the measurement of skin temperature, and the calculation of blood flow are made, respectively, data indicating the relationship between the amount of sweating and blood flow, 5. The biological data measuring device according to claim 1, wherein data indicating a relationship with a blood flow is stored in the memory area for each subject.

The memory area stores body surface area conversion data representing a relationship between body data and body surface area including at least one of a person's height, weight, age, and gender,
While the calculation means calculates the body surface area of the subject from the body data of the subject and the body surface area conversion data,
The skin temperature of the subject is calculated from the measured skin temperature measured by the sweating / skin temperature measuring means or the calculated skin temperature based on the data indicating the relationship between the skin temperature and the blood flow rate by the computing means. 6. The biological data measuring apparatus according to claim 5, wherein an average value is calculated, and a heat consumption amount required for the subject is calculated from the average value of the skin temperature and the body surface area.

While the photoelectric sensor irradiates light in a wavelength band that is absorbed and reflected by both oxyhemoglobin and reduced hemoglobin in the blood vessel,
The computing means calculates a change amount of the contents of both hemoglobins based on a change in the amount of transmitted light or reflected light, and calculates a relative change amount of the blood flow based on the contents of both hemoglobins. The biological data measuring device according to claim 1.