JPH0120906B2

JPH0120906B2 -

Info

Publication number: JPH0120906B2
Application number: JP56197874A
Authority: JP
Inventors: Tatsuo Suzuki
Original assignee: Terumo Corp
Current assignee: Terumo Corp
Priority date: 1981-12-09
Filing date: 1981-12-09
Publication date: 1989-04-19
Also published as: JPS5899971A

Description

【発明の詳細な説明】発明の背景技術分野本発明は呼吸回路に関する。先行技術とその問題点呼吸回路として、機械的人工呼吸を行うため
に、レスピレーター（ベンチレーターとも称され
る）に接続して用いる回路や、患者に、例えば麻
酔ガスと酸素ガスなどを投与する麻酔用の回路
や、薬剤や酸素等を投与する吸入療法用の回路な
ど、種々のものが用いられている。そして、これら各種呼吸回路は、基本的には、
レスピレーター、麻酔器などと、患者側の気管カ
テーテル、マスク等を連結する吸気導入管と、呼
気排出管とから構成される。従来用いられている呼吸回路の一つとして、例
えば第１図に示されるようなものがある。この回
路は、レスピレーターＲの吸気側に、加温加湿器
Ｈを介し吸気導入管Ｉを接続し、また呼気側に呼
気排出管Ｅを接続し、両者をＹ字型のコネクタＣ
に接続し、患者側の気管カテーテル等を連結して
なり、さらに、吸気導入管Ｉの途中に、気管支拡
張剤、喀痰溶解剤等の薬剤をエアゾールとして気
道に吸入させるためのネブライザー６が挿入さ
れ、また呼気排出管Ｅの途中に呼気弁７が挿入さ
れている。しかし、このような回路では、吸気導入管Ｉと
呼気排出管Ｅが別々になつているので、全体的に
大きくなり、取り扱いに不便である。また、吸気ガスは、加温加湿器Ｈにより加温加
湿されて送気されるものであるが、吸気導入管Ｉ
を通過する間に熱損失により温度が下り、患者に
望まれる温度および水分を与えるのが困難であ
る。この場合、適温の吸気ガスを患者に与えるに
は、加温加湿器Ｈで相当高温にしたガスを送れば
よいが、このとき管内に結露した水が大量に発生
し、頻繁に水抜きを行わなければならず、また、
何らかのトラブルにより、患者が高温ガスを吸入
してしまう危険性が高い。さらに、患者の口元近くには、コネクタＣを介
し、２本の管があり、特に、口元近くで、回路内
圧や吸気ガス温度等をモニターするときには、各
種装置が必要となり、口元近くの構造はきわめて
複雑となり、患者にとつてきわめて煩わしいもの
となり、またその取扱いも面倒となる。これに対し、主に麻酔に用いられる呼吸回路と
して、例えば第２図に示されるような、ベイン回
路ないしＦ回路が知られている。このような回路は、例えば直管状の内管１５と
又、通常蛇腹状の外管１１とから、これらを同軸
配置して二重管１を構成し、内管１５内を呼吸回
路、外管１１内管１５間の空間を呼気回路とす
る。そして、二重管１の患者側の一端を給排気口
３１を有するコネクタ３と連結する。又、外管１
１と内管１５との麻酔器Ａ側の他端は、それぞれ
基体５に取付け、基体５の内管連通孔５３および
外管連通孔５１を介し、麻酔器Ａから送気および
換気を行う。このような回路は、二重管を用いるので、取扱
いが容易であり、このような回路を用いれば、上
記のように吸気管Ｉと呼気管Ｅとを独立の管とし
て設ける場合と比較して、吸気回路としての内管
１５の外側に外管１１が存在すること、そして、
内管１５外周には呼気ガスが接触することから、
吸気ガスの熱損失は小さくなる。しかし、このような回路は、呼気弁およびネブ
ライザーを具えておらず、また、二重管を用いる
ので、その途中にこれらを挿入することもでき
ず、使用できるレスピレーターの機種が限られて
しまうという欠点がある。このような実状に鑑み、本発明者は、先に、こ
れら各種不都合を解消した呼吸回路として、第３
図および第４図に示されるようなものを提案して
いる（特願昭56−49278号、特公昭61−52706号）。この回路は、上記のような外管１１，１１′お
よび内管１５，１５′からなる二重管１，１′を２
つ用い、この中間に連結部２′を挿入し、この連
結部２′に、ネブライザー６および呼気弁７を設
けてなるものである。この場合、連結部２′は、外側管体２１′と内側
管体２２′とから形成される。そして、この連結部２′の途中には、吸気導入
用の内管１５，１５′と接続する内側管体２２′の
みを連通するように、しかも連結部２′の外側管
体２１′を遮断するように、ネブライザー６が配
置される。また、呼気排出用の外管１５，１５′
と接続する外側管体２１′には、呼気弁７が設け
られ、さきのネブライザー６を迂回するように、
外側管体２１′と呼気弁７との間に側路２７′が設
けられている。なお、図中、患者側においては、二重管１にコ
ネクタ３およびコネクタC₅が付され、また、レ
スピレーター側においては、送気用チユーブT₁
およびコネクタC₁を介し換気用チユーブT₂を付
した基体５が接続される。このような先の提案に係る回路によれば、上記
した各種不都合はすべて解消するものである。し
かし、このような回路は、連結部２′のレスピレ
ータ側も二重管構造とするので、呼気および吸気
抵抗が高く、これらを減少するためには、管寸法
を大きくしなければならず、コンパクトさにかけ
るという欠点がある。発明の目的本発明は、このような実状に鑑みなされたもの
であつて、その主たる目的は、構造がシンプルか
つコンパクトで、取り扱いが容易であり、しかも
熱損失が少なく、結露水分量が少なく、さらに呼
気および吸気抵抗が小さく、加えてネブライザー
と呼気弁を具え、レスピレーターに対する汎用性
のすぐれた呼吸回路を提供することにある。本発明者は、このような目的につき、レスピレ
ータ側を二重管構造としないために種々検討を行
い、本発明をなすに至つた。すなわち本発明は、外管と内管とから構成され
る二重管を有し、当該二重管の患者側の一端に、
吸排気口を具えるコネクタを接続し、また前記二
重管の他端を、ネブライザーと呼気弁とを具える
連結部に接続し、当該連結部において、前記ネブ
ライザーを前記外管および内管のうちの一方と、
また前記呼気弁を前記外管および内管のうちの他
方と連通させ、前記連結部のネブライザーに連通
する接続口部に、吸気導入管を連結し、前記連結
部の呼気弁に連通する接続口部に、前記吸気導入
管とは独立に呼気排出管を接続したことを特徴と
する呼吸回路である。なお、本発明の実施態様は、上記した目的をさ
らに有効に実現するための具体的構造に関するも
のであり、以下のとおりである。）呼気排出管および吸気導入管が蛇腹管であ
る本発明の呼吸回路。これにより、安全性と取り扱いやすさとが向
上する。）二重管を構成する外管が呼気管であり、内
管が吸気管である本発明または上記）の呼吸
回路。このとき熱損失がきわめて小さくなる。）連結部が、外側管体と内側管体とからなる
二重部を有し、しかも当該二重部の内側管体に
連通するようにネブライザーが設けられてお
り、当該ネブライザーに連通する接続口部が設
けられ、また前記二重部の外側管体に連通する
ように呼気弁が設けられており、当該呼気弁に
連通する接続口部が設けられ、さらに前記連結
部の二重部の外側管体および内側管体の端部
に、それぞれ、外管および内管が連結されてい
る上記）の呼吸回路。このとき構造はきわめて簡易となる。）二重管を構成する外管が蛇腹管である本発
明または上記）ないし）のいずれかの呼吸
回路。このとき、安全性および取り扱いやすさが向
上する。）呼気排出管が接続されている接続口部が、
呼気弁に脱着自在に接続可能である本発明また
は上記）ないし）のいずれかの呼吸回路。このとき、吸入療法用の回路として、有用性
がます。）コネクタが給排気口とそれぞれ連通する外
管取付口および内管取付口を有し、二重管の外
管および内管が、それぞれ、当該外管取付口お
よび内管取付口に連結されている本発明または
上記）〜）のいずれかの呼吸回路。このとき、回路の伸びに伴う機械的死腔量が
減少する。発明の具体的構成以下、本発明を、第５図〜第８図に示される実
施例に従い、詳細に説明する。本発明の呼吸回路は、外管１１と内管１５とか
ら構成される二重管１を有する。外管１１と内管
１５とから二重管を構成するには、図示のよう
に、ほぼ等長の外管１１と内管１５とを、ほぼ同
軸配置する。この場合、内管１５を吸気管、外管１１を呼気
管として、内管１５を吸気回路、外管１１内管１
５間の空間を呼気回路とすれば、吸気ガスの熱損
失が減少し、好ましい結果を得る。用いる外管１１は、蛇腹管とすることが好まし
い。これにより、キンキング、すなわちねじれや
折れ曲がりによる回路のつぶれが減少するからで
ある。これに対し、内管１５は、径が小さく、キンキ
ングがおこりにくいので、蛇腹管であつても直管
であつてもよい。用いる外管１１と内管１５を構成する材質は、
ともに同一でも異つていてもよく、公知の可撓性
チユーブ材料、例えばポリエチレン、ポリプロピ
レン、ポリアミド、ポリ塩化ビニル、ポリエステ
ル、ポリウレタン、ポリ酢酸ビニル等の中から適
宜選択すればよい。また、内管１５および外管１１の寸法も種々変
更可能である。この場合、内管１５および外管１１の内径は、
それぞれ概ね８〜20mm程度および20〜30mm程度と
すればよく、これらの比は１：1.5〜１：2.5程度
とすればよい。更に、蛇腹管とするときの山部外径と谷部外径
の差は、概ね1.5〜５mm程度とすればよく、又蛇
腹頂部の曲率半径も、概ね0.5〜1.5mm程度とすれ
ばよい。さらに、両者の平均肉厚は、互いに同一でも異
なつていてもよいが、通常は、ともに0.3〜１mm
程度とすればよい。なお、その長さは30cm〜90cm程度とすればよ
い。このように、用いる内管１５および外管１１は
種々のものとすることができるが、回路内圧が上
昇したとき、回路の伸びが小さく、機械的死腔量
が小さく、気道抵抗が変動しても死腔量が変動せ
ず、換気量の調節を行わなくてすむという点で
は、内管を外管より伸び率の少ない材質から構成
することが好ましい。このように構成するには、外管１１と蛇腹管と
して、内管１５を直管とするか、あるいは両者を
蛇腹管として、内管の山部の外径と谷部の外径と
の差を外管のそれより小とするか、内管の蛇腹頂
部の曲率半径を外管のそれより小とする等があ
る。また、外管の平均肉厚を、内管のそれより大と
すれば、熱損失はより一層少なくなり、好ましい
結果を得る。このように構成される二重管１の一端はコネク
タ３と接続されている。コネクタ３としては、第８図ａ〜ｃに示される
ように、給排気口３１を有し、二重管１の患者側
一端がそれと連通するものであればよい。このため、一般には、コネクタ３は、少なくと
も外管１１の一端を嵌着可能な、上記給排気口３
１と連通する外管取付口３３を有するものであ
る。すなわち、二重管１の患者側一端の内管１５
の端部は、コネクタ３内に固定されず配置されて
いてもよい。ただ、コネクタ３には、二重管１の
患者側一端に位置する内管１５をも嵌着固定でき
るようにすると、吸気時の回路内圧の上昇による
回路の伸びが減少し、機械的死腔が減少する点で
好ましい。このような例が、第８図ａ〜ｃに示される。同
図において、コネクタ３は、先端を外管取付口３
３とし、後端を給排気口３１とする筒状体からな
り、この内部に筒状の内管取付口３４を同軸配置
し、内管取付口３４と外管取付口３３とを４枚の
羽根３６により連結してなり、これらを合成樹脂
等から一体的に成形加工して形成されている。なお、図示の例では、コネクタ３には、モニタ
ー孔３８が設けられ、第５図に示される圧力モニ
ター用チユーブ３８１を付し、回路内圧や吸気温
度等をモニターできるように構成されている。これに対し、二重管１の他端は連結部２に接続
されている。連結部２は、ネブライザー６と呼気弁７とを具
える。連結部２において、ネブライザー６は、連結部
２に接続される外管１１と内管１５のうちの一方
のみと連通し、しかも後述の吸気導入管５を接続
するための接続口部２７と連通するように設けら
れる。また、呼気弁７は、連結される外管１１と内管
１５のうちの他方とのみ連通し、しかも後述の呼
気排出管４を接続するための接続口部２６と連通
するように配置される。このように配置するには、種々の構造が可能で
あるが、構造がきわめて簡易となり、小型コンパ
クトとなるようにするためには、第５図〜第７図
に示されるように、連結部２が外側管体２１１と
内側管体２１５からなる二重部２１を有するよう
に構成し、内側管体２１５の患者側端部に二重管
１の内管を嵌着できるようになし、また、その他
端にネブライザー６を連通配置し、さらにネブラ
イザー６に管状の接続口部２７を連通させ、一
方、外側管体２１１には、呼気弁７を設け、それ
と連通させ、呼気弁７に管状の接続口部２６を連
通させて設けることが好ましい。このような場合
には、内側管体２１５−ネブライザー６−接続口
部２７の連通空間が吸気回路を構成し、これと隔
てられる外側管体２１１−呼気弁７−接続口部２
６の連通空間が呼気回路を構成する。用いるネブライザー６として、超音波によりエ
アゾールを発生させる、いわゆる超音波ネブライ
ザーであつてもよいが、一般には、ベンチユリー
効果を利用してエアゾールを発生させる、いわゆ
るベンチユリータイプのネブライザーを用いるこ
とが好ましい。ベンチユリータイプのネブライザーは、通常、
第７図に示されるように、上記したようにして、
吸気回路内に容器６１を挿入連結し、この容器６
１内にノズル６２を設けてなる。このノズル６２には、吸気時において、外部か
らチユーブ６９を介し、ジエツト気流を流入させ
るようにする。一方、容器６１内には、薬剤容液６４を充填
し、更に容器６１底部には吸い上げ管６５を配置
し、噴射ノズル６３を、この吸い上げ管６５と連
通させるとともに、噴射ノズル６３を、ノズル６
２の近傍に、通常ノズル６２と直角に対向して配
置する。このような構成で、ジエツト気流をノズル６２
から容器６１内に流入させると、ジエツト気流に
より、噴射ノズル６３の口元は陰圧となり、薬剤
溶液は吸い上げ管６５を介し吸い上げられ、ノズ
ル６３からエアゾール化される。なお、図示の場合には、容器底部６１２の内側
底面は円錐状をなし、所望の量の薬液を無駄なく
吸い上げることができるようにしている。又、噴射ノズル６３からエアゾール化された薬
剤溶液は、ジエツト気流とともにバツフル６８に
あたり、さらに、飛散することにより、粒子径が
均一化するようにされている。このようなネブライザー６には、一体的に連結
される二重部２１と逆側に、接続口部２７が一体
的に連結されている。他方、呼気弁７としては、取扱いやすさの点で
ダイヤフラム式のものが好ましい。第７図には呼気弁７の好ましい例が示される。この場合、呼気弁７は、連結部２の二重部２１
の外側管体２１１と一体的に連結して形成された
筒状の入口部７２と、入口部７２と一体的に同心
配置され、接続口部２６を連結した出口部７３と
を具え、入口部７２内が入口室７２１、出口部７
３入口部７２間が出口室７３１を形成する。一方、出口部７３には加圧口７５を有する蓋７
４が螺着等により付され、蓋７４内部の隔室７４
１と出口室７３１、入口室７２１とはダイヤフラ
ム７１で仕切られる。このような構成で、加圧口７５からチユーブ７
９を介し、吸気時に隔室７４１の加圧を行えば、
ダイヤフラム７１は入口部７２に押しつけられ、
弁が閉じ、又呼気時に隔室７４１内の圧力を解除
すれば、ダイヤフラム７１は開放し、弁が開くこ
とになる。そして、呼気時に所定の陽圧（例えば
５cmH₂O）となるような圧力解除を行えば、肺
胞のつぶれ等の危険性を少なくするなどのための
ピープ（PEEP）療法の適用が可能となる。このような呼気弁７には、例えばＬ字状に屈曲
して、接続口部２６が一体的に連結される。なお、第５図等に示される例では、連結部２に
はつり下げ用の把手２８が設けられている。このような連結部２の接続口部２６，２７に
は、それぞれ呼気排出管４および吸気導入管５が
接続される。呼気排出管４と吸気導入管５とは、キンキング
によるつぶれ防止の観点から、ともに蛇腹管を用
いることが好ましいが、それ以外には特に制限は
ない。従つて、前記二重管１の内管および外管につい
て触れたような通常の材質、寸法のものとするこ
とができるなお、その長さは、それぞれ、一般に60cm〜
120cm程度とされる。このような呼気排出管４と吸気導入管５とは、
それぞれ、上記連結部２に接続口部２６，２７を
介して接続されるが、呼気排出管４は接続口部２
６に常時接続しておき、この接続口部２６の呼気
弁側が呼気弁７に脱着自在に接続可能とすること
が好ましい。すなわち、第６図に示すように、呼気弁７が接
続口部２６に対する受口２６′を有するものとし、
該受口２６′と前記接続口部２６とをテーパー嵌
合により接続可能とするとよい。このようにして、呼気排出管４が接続されてい
る接続口部２６を、呼気弁７に脱着自在に接続可
能とすることにより、呼気排出管４を呼気弁７か
ら取り外すと、換気量計を必要としない吸入療法
用の回路として用いることができ、また、呼気弁
７に小型の換気量計を接続することができる為、
レスピレーター内に換気量計を有していないレス
ピレーターにも使用することができることにな
り、汎用性に優れ、さらに構造もシンプルとな
る。発明の具体的作用本発明の呼吸回路を用いて、機械的人工呼吸な
いし吸入療法を行うに際しては、呼気排出管４お
よび吸気導入管５に、それぞれ、例えばコネクタ
C₆およびC₇を接続し、あるいは必要に応じ呼気
排出管４を連結部２の呼気弁７からとりはずし、
加温加湿器あるいは呼気流量計等を介し、レスピ
レーターＲ、あるいは麻酔器等と接続する。ま
た、コネクタ３に、例えばＬ字コネクタC₅を接
続し、患者側の気管カテーテルやマスク等と連結
する。このようにして、レスピレーターあるいは麻酔
器等から送られてくる吸気ガスは、吸気導入管５
を通り、ネブライザー６を経て、内管１５から患
者に送られる。また、患者からの呼気ガスは、内管１５と外管
１１の間を通り、呼気弁７を経た後、例えば呼気
排出管４に入り排出される。発明の具体的効果本発明の呼吸回路は、全体的にきわめてシンプ
ル、かつコンパクトな構造をもつ。特に、患者口
元付近は、二重管構造であるので、取り扱いはき
わめて簡易となり、患者の煩しさもない。また、呼気弁７と、ネブライザー６とを有する
ので、使用可能なレスピレーター等の機種、仕様
等が限定されない。加えて、機械的人工呼吸にも
また吸入療法にもさらに麻酔にも使用できるとい
う汎用性をもつ。さらに、連結部と患者との間が二重管構造とな
つているので、熱損失が少ない。このため、吸気
ガスの加温温度を低くでき、回路内の貯留水が少
なくなり、高温ガスを患者が吸入する危険性も少
なくなる。そして、これらのすぐれた効果を発揮した上
で、本発明では、二重管構造を、連結部と患者と
の間のみとするので、吸気および呼気抵抗が小さ
くなるという効果が奏される。この場合、後記実験例からも明らかなように、
患者とレスピレーターとの間を全て二重管構造と
するときと比較すると、熱損失を同等に小さく保
持した上で、吸気および呼気抵抗は格段と減少す
る。また、同等の吸気および呼気抵抗を示す管径
は格段と小さくなり、二重管１がコンパクトにな
るという効果が実現する。そして、上記した実施態様）に従い、呼気排
出管と吸気導入管とを、ともに蛇腹管とすれば、
キンキングによるつぶれが少なくなり、安全性と
取り扱いやすさとが向上する。実施態様）に従い、二重管の外管を呼気管、
内管を吸気管とすれば熱損失の点できわめて有利
である。実施態様）に従い、第７図のように、連結部
に二重部を設ければ、構造がきわめて簡易とな
る。実施態様）に従い、外管を蛇腹管とすれば、
キンキングによるつぶれが少なくなる。実施態様）に従い、呼気排出管が接続されて
いる接続口部が、呼気弁に脱着自在に接続可能と
すれば、呼気排出管を呼気弁から取り外したと
き、換気量計を必要としない吸入療法用の回路と
して用いることができ、また呼気弁に小型の換気
量計を接続することが可能となり、レスピレータ
ー内に換気量計を有していないレスピレーターに
も使用することができることになり、汎用性が増
し、全体的な構造もきわめてシンプルとなる。実施態様）に従い、コネクタを外管および内
管と連結すれば、回路の伸びに伴なう機械的死腔
量が減少し、より好ましい結果を得る。本発明は、本発明のの効果を確認するため種々
実験を行つた。以下にその１例を示す。実験例第１図（下記比較１）、第２図（下記比較２）、
第３図および第４図（下記比較３）の３種の比較
用回路ならびに第５図〜第８図に示される下記本
発明の回路を作製し、その一端をレスピレーター
と加温加湿器を介して接続し、また、その他端を
温度37℃、相対湿度100％に保持した模擬肺と接
続し、それぞれの回路特性を評価した。この場合、第５図〜第８図に示される本発明の
呼吸回路では、用いる二重管１を構成する内管１
５として、谷部内径13.5mm、山部内径15mm、全長
60cmのポリエチレン製の蛇腹管を用い、また、二
重管１を構成する外管１１として、この内管１５
と同長で、谷部内径23.5mm、山部内径28mmのポリ
エチレン製の蛇腹管を用いた。また、それぞれ一重管構造とする呼気排出管４
と、吸気導入管５としては、それぞれ、谷部内径
23.5mm、山部内径28mmで、60cm長のポリエチレン
製の蛇腹管を用いた。これに対し、第１図、第２図ならびに第３図お
よび第４図にそれぞれ示される各比較用呼吸回路
（比較１、２、３）においては、二重管を構成す
るときの外管および内管、そして一重管構造とす
るときのそれぞれの管は、それぞれ対応する、上
記した本発明に属する呼吸回路における管と、ほ
ぼ同寸法の管断面寸法とした。また、これら３種
の各比較用呼吸回路において、その管部分の全長
は120cmとし、上記した本発明に属する呼吸回路
におけるそれと一致させた。以上のような、本発明、あるいは比較用の計４
種の呼吸回路につき、それぞれ、下記表１に示さ
れるような条件にて、吸気ガスを加温加湿器で加
温および加湿しながら、レスピレーターを２時間
作動させた。レスピレーターを２時間作動した後における模
擬肺の口元での温度（℃）を下記表１に示す。また、レスピレーターを２時間作動した後にお
ける単位体積あたりの回路中の貯留水の量（g/
m³）を測定した。結果を下記表１に示す。この場合、貯留水の量は、第２図に示されるよ
うな比較２以外は、加温加湿器連結部間と、連結
部模擬肺間とで別途測定した。これらの結果を下記表１に示す。さらに、上記した計４種の各呼吸回路につき、
流量を30／minとしたときの、呼気抵抗（cm
H₂O／／sec）と、吸気抵抗（cmH₂O／／
sec）とを測定した。結果を下記表１に併記する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to breathing circuits. Prior art and its problems Breathing circuits include circuits connected to respirators (also called ventilators) for mechanical ventilation, and anesthesia circuits that administer anesthetic gas and oxygen gas to patients, for example. A variety of circuits are used, including circuits for inhalation therapy and circuits for inhalation therapy that administer drugs, oxygen, etc. These various breathing circuits are basically
It consists of an inhalation inlet tube that connects a respirator, anesthesia machine, etc., a patient's tracheal catheter, mask, etc., and an exhalation outlet tube. One of the conventionally used breathing circuits is one shown in FIG. 1, for example. This circuit connects an inhalation inlet pipe I to the inhalation side of a respirator R via a heating humidifier H, and connects an exhalation discharge pipe E to the exhalation side, connecting both with a Y-shaped connector C.
A tracheal catheter or the like on the patient's side is connected to the tube, and a nebulizer 6 is inserted in the middle of the suction introduction tube I to inhale drugs such as bronchodilators and sputum dissolvers into the respiratory tract as aerosols. Also, an exhalation valve 7 is inserted in the middle of the exhalation discharge pipe E. However, in such a circuit, the intake pipe I and the expiration discharge pipe E are separate, so the overall size is large and it is inconvenient to handle. In addition, the intake gas is heated and humidified by the heating humidifier H before being sent, but the intake gas is supplied through the intake air introduction pipe I.
During passage through the body, the temperature drops due to heat loss, making it difficult to provide the desired temperature and hydration to the patient. In this case, in order to provide the patient with inspiratory gas at an appropriate temperature, it is possible to send gas heated to a considerably high temperature using the humidifier H, but at this time a large amount of condensed water is generated in the pipes, and the water must be drained frequently. Must also be
There is a high risk that the patient will inhale high-temperature gas due to some kind of trouble. Furthermore, there are two tubes near the patient's mouth via connector C, and in particular, when monitoring the internal circuit pressure, intake gas temperature, etc. near the patient's mouth, various devices are required, and the structure near the mouth is It is extremely complex, extremely bothersome for the patient, and difficult to handle. On the other hand, as a breathing circuit mainly used for anesthesia, a Bain circuit or an F circuit as shown in FIG. 2, for example, is known. Such a circuit consists of, for example, a straight inner tube 15 and a usually bellows-shaped outer tube 11, which are arranged coaxially to form a double tube 1, and the inside of the inner tube 15 is connected to a breathing circuit and an outer tube. The space between the inner tubes 11 and 15 is used as an exhalation circuit. Then, one end of the double tube 1 on the patient side is connected to a connector 3 having an air supply/exhaust port 31. Also, outer tube 1
The other ends of the anesthesia machine A side of the anesthesia machine A and the inner tube 15 are respectively attached to the base body 5, and air is supplied and ventilated from the anesthesia machine A through the inner tube communication hole 53 and the outer tube communication hole 51 of the base body 5. Since such a circuit uses a double pipe, it is easy to handle, and if such a circuit is used, compared to the case where the intake pipe I and the expiration pipe E are provided as independent pipes as described above, , the outer pipe 11 is present outside the inner pipe 15 as an intake circuit, and
Since exhaled gas comes into contact with the outer periphery of the inner tube 15,
The heat loss of the intake gas is reduced. However, such a circuit does not include an exhalation valve or nebulizer, and since it uses a double tube, it is not possible to insert these in the middle, which limits the types of respirators that can be used. There are drawbacks. In view of these circumstances, the inventors of the present invention have developed a third breathing circuit that eliminates these various inconveniences.
They have proposed something as shown in Fig. 4 (Japanese Patent Application No. 56-49278, Japanese Patent Publication No. 61-52706). This circuit consists of two double pipes 1, 1' consisting of outer pipes 11, 11' and inner pipes 15, 15' as described above.
A connecting portion 2' is inserted between the two, and a nebulizer 6 and an exhalation valve 7 are provided in this connecting portion 2'. In this case, the connecting portion 2' is formed from an outer tube 21' and an inner tube 22'. In the middle of this connecting part 2', only the inner pipe body 22' connected to the inner pipes 15, 15' for intake air introduction is communicated, and the outer pipe body 21' of the connecting part 2' is cut off. The nebulizer 6 is arranged so as to. In addition, outer tubes 15, 15' for exhaled air discharge are also provided.
An exhalation valve 7 is provided on the outer pipe body 21' connected to the exhalation valve 7, so as to bypass the nebulizer 6.
A side channel 27' is provided between the outer tube 21' and the exhalation valve 7. In addition, in the figure, on the patient side, connector 3 and connector C ₅ are attached to the double tube 1, and on the respirator side, an air supply tube T ₁ is attached.
A base body 5 with a ventilation tube T ₂ is connected via the connector C ₁ . According to the circuit according to the previous proposal, all of the above-mentioned various disadvantages can be solved. However, in such a circuit, the respirator side of the connection part 2' also has a double pipe structure, so the exhalation and inhalation resistance is high, and in order to reduce these resistances, the pipe size must be increased, making it compact. It has the disadvantage of being too expensive. Purpose of the Invention The present invention was made in view of the above-mentioned circumstances, and its main purpose is to have a simple and compact structure, easy handling, low heat loss, low condensed water content, Furthermore, the object is to provide a highly versatile breathing circuit for respirators, which has low expiratory and inspiratory resistance, and is equipped with a nebulizer and an exhalation valve. For this purpose, the present inventor conducted various studies in order to avoid having a double pipe structure on the respirator side, and came up with the present invention. That is, the present invention has a double tube composed of an outer tube and an inner tube, and at one end of the double tube on the patient side,
A connector provided with an inlet and an exhaust port is connected, and the other end of the double tube is connected to a connection part provided with a nebulizer and an exhalation valve, where the nebulizer is connected to the outer tube and the inner tube. One of us and
Further, the exhalation valve is communicated with the other of the outer tube and the inner tube, an inhalation introduction tube is connected to a connection port portion of the connection portion that communicates with the nebulizer, and a connection port that communicates with the exhalation valve of the connection portion. This breathing circuit is characterized in that an exhalation exhaust pipe is connected to the air intake pipe independently of the intake air introduction pipe. Note that the embodiments of the present invention relate to specific structures for more effectively realizing the above-mentioned objects, and are as follows. ) The breathing circuit of the present invention, wherein the exhalation discharge pipe and the intake intake pipe are bellows pipes. This improves safety and ease of handling. ) The breathing circuit of the present invention or the above), wherein the outer pipe constituting the double pipe is an expiratory pipe and the inner pipe is an inhalation pipe. At this time, heat loss becomes extremely small. ) The connecting part has a double part consisting of an outer pipe body and an inner pipe body, and a nebulizer is provided so as to communicate with the inner pipe part of the double part, and a connection port communicating with the nebulizer is provided. An exhalation valve is provided so as to communicate with the outer tubular body of the double portion, and a connection port portion that communicates with the exhalation valve is provided, and an outer pipe of the double portion of the connection portion is provided with an exhalation valve that communicates with the outer pipe body of the double portion. The above-mentioned breathing circuit in which an outer tube and an inner tube are connected to the ends of the tube body and the inner tube body, respectively. At this time, the structure becomes extremely simple. ) The breathing circuit of the present invention or any one of the above) through), wherein the outer tube constituting the double tube is a bellows tube. At this time, safety and ease of handling are improved. ) The connection port to which the exhalation discharge pipe is connected is
The breathing circuit of the present invention or any one of (a) and (b) above, which is detachably connectable to an exhalation valve. At this time, it becomes useful as a circuit for inhalation therapy. ) The connector has an outer tube attachment port and an inner tube attachment port that communicate with the supply/exhaust port, respectively, and the outer tube and inner tube of the double pipe are connected to the outer tube attachment port and the inner tube attachment port, respectively. The breathing circuit according to the present invention or any of the above). At this time, the amount of mechanical dead space associated with the elongation of the circuit decreases. Specific Structure of the Invention The present invention will be described in detail below in accordance with the embodiments shown in FIGS. 5 to 8. The breathing circuit of the present invention has a double tube 1 composed of an outer tube 11 and an inner tube 15. To construct a double tube from the outer tube 11 and the inner tube 15, the outer tube 11 and the inner tube 15, which have approximately the same length, are arranged approximately coaxially as shown in the figure. In this case, the inner tube 15 is used as an inhalation tube, the outer tube 11 is used as an exhalation tube, and the inner tube 15 is used as an inhalation circuit, and the outer tube 11 and the inner tube 1
If the space between 5 and 5 is used as an exhalation circuit, the heat loss of the inhaled gas will be reduced and favorable results will be obtained. The outer tube 11 used is preferably a bellows tube. This is because kinking, that is, damage to the circuit due to twisting or bending, is reduced. On the other hand, the inner tube 15 has a small diameter and is less prone to kinking, so it may be a bellows tube or a straight tube. The materials used to construct the outer tube 11 and inner tube 15 are as follows:
They may be the same or different, and may be appropriately selected from known flexible tube materials such as polyethylene, polypropylene, polyamide, polyvinyl chloride, polyester, polyurethane, polyvinyl acetate, and the like. Further, the dimensions of the inner tube 15 and the outer tube 11 can also be changed in various ways. In this case, the inner diameters of the inner tube 15 and outer tube 11 are:
They may be approximately 8 to 20 mm and 20 to 30 mm, respectively, and the ratio thereof may be approximately 1:1.5 to 1:2.5. Furthermore, when forming a bellows tube, the difference between the outer diameter of the peak and the outer diameter of the valley may be approximately 1.5 to 5 mm, and the radius of curvature of the top of the bellows may be approximately 0.5 to 1.5 mm. Furthermore, the average thickness of both may be the same or different, but usually both are 0.3 to 1 mm.
It is sufficient to set it to a certain degree. Note that the length may be approximately 30 cm to 90 cm. In this way, various types of inner tube 15 and outer tube 11 can be used, but when the internal pressure of the circuit increases, the elongation of the circuit is small, the amount of mechanical dead space is small, and the airway resistance fluctuates. It is preferable that the inner tube is made of a material with a lower elongation rate than the outer tube, since the amount of dead space does not change and there is no need to adjust the ventilation amount. To configure this, the outer tube 11 and the bellows tube may be used, and the inner tube 15 may be a straight tube, or both may be bellows tubes, and the difference between the outer diameter of the crest and the outer diameter of the trough of the inner tube may be changed. be smaller than that of the outer tube, or the radius of curvature of the bellows top of the inner tube may be smaller than that of the outer tube. Moreover, if the average wall thickness of the outer tube is made larger than that of the inner tube, heat loss will be further reduced and a favorable result will be obtained. One end of the double pipe 1 constructed in this way is connected to a connector 3. The connector 3 may be any connector as long as it has an air supply/exhaust port 31 and one end of the double tube 1 on the patient side communicates with the air supply/exhaust port 31, as shown in FIGS. 8a to 8c. For this reason, the connector 3 generally has the above-mentioned supply/exhaust port 3 into which at least one end of the outer tube 11 can be fitted.
It has an outer tube attachment port 33 that communicates with 1. That is, the inner tube 15 at one end of the double tube 1 on the patient side
The end portion of the connector 3 may be arranged without being fixed within the connector 3. However, if the inner tube 15 located at one end of the double tube 1 on the patient side can also be fitted and fixed into the connector 3, the elongation of the circuit due to the increase in the pressure inside the circuit during inspiration will be reduced, and the mechanical dead space will be reduced. This is preferable in that it reduces. Such examples are shown in Figures 8a-c. In the same figure, the connector 3 has its tip connected to the outer tube attachment port 3.
3, it is made of a cylindrical body with the rear end serving as an air supply/exhaust port 31, and a cylindrical inner pipe attachment port 34 is coaxially arranged inside this body, and the inner tube attachment port 34 and the outer tube attachment port 33 are connected to each other by four pieces. They are connected by blades 36, and are integrally molded from synthetic resin or the like. In the illustrated example, the connector 3 is provided with a monitor hole 38 and is equipped with a pressure monitor tube 381 shown in FIG. 5, so that the internal pressure of the circuit, the intake air temperature, etc. can be monitored. On the other hand, the other end of the double pipe 1 is connected to the connecting part 2. The connecting part 2 includes a nebulizer 6 and an exhalation valve 7. In the connecting part 2, the nebulizer 6 communicates with only one of the outer pipe 11 and the inner pipe 15 connected to the connecting part 2, and moreover, communicates with a connecting port part 27 for connecting the intake introduction pipe 5, which will be described later. It is set up so that Further, the exhalation valve 7 is arranged so as to communicate only with the other of the outer pipe 11 and the inner pipe 15 that are connected, and moreover, to communicate with a connection port 26 for connecting the exhalation discharge pipe 4, which will be described later. . Various structures are possible for this arrangement, but in order to make the structure extremely simple and compact, the connecting portion 2 should be arranged as shown in FIGS. 5 to 7. is configured to have a double portion 21 consisting of an outer tube body 211 and an inner tube body 215, so that the inner tube of the double tube 1 can be fitted to the patient side end of the inner tube body 215, and A nebulizer 6 is disposed in communication with the other end, and a tubular connection port 27 is communicated with the nebulizer 6. On the other hand, an exhalation valve 7 is provided on the outer tubular body 211 and communicated therewith, and a tubular connection port 27 is connected to the exhalation valve 7. It is preferable that the mouth portion 26 be provided in communication with each other. In such a case, the communication space between the inner tubular body 215, the nebulizer 6, and the connection port 27 forms an inhalation circuit, and the communication space between the outer tubular body 211, the exhalation valve 7, and the connection port 2, which is separated from this, constitutes an inhalation circuit.
6 communication spaces constitute an exhalation circuit. The nebulizer 6 used may be a so-called ultrasonic nebulizer that generates an aerosol using ultrasonic waves, but it is generally preferable to use a so-called ventuille type nebulizer that generates an aerosol using the ventuille effect. Ventilation type nebulizers usually
As shown in FIG. 7, as described above,
A container 61 is inserted and connected into the intake circuit, and this container 6
1, a nozzle 62 is provided within the nozzle 1. A jet airflow is allowed to flow into this nozzle 62 from the outside through a tube 69 during intake. On the other hand, the container 61 is filled with a medicine liquid 64, and a suction tube 65 is arranged at the bottom of the container 61, and the injection nozzle 63 is communicated with the suction tube 65.
The nozzle 62 is normally disposed near the nozzle 2 and facing the nozzle 62 at right angles. With this configuration, the jet airflow is directed to the nozzle 62.
When the drug solution is caused to flow into the container 61, the mouth of the injection nozzle 63 becomes a negative pressure due to the jet air flow, and the drug solution is sucked up through the suction tube 65 and aerosolized from the nozzle 63. In the illustrated case, the inner bottom surface of the container bottom 612 has a conical shape, so that a desired amount of the medicinal solution can be sucked up without waste. Further, the drug solution aerosolized from the injection nozzle 63 hits the baffle 68 together with the jet airflow and is further scattered, thereby making the particle size uniform. In such a nebulizer 6, a connection port part 27 is integrally connected to the opposite side of the double part 21 which is integrally connected. On the other hand, the exhalation valve 7 is preferably of a diaphragm type in terms of ease of handling. A preferred example of the exhalation valve 7 is shown in FIG. In this case, the exhalation valve 7 is connected to the double part 21 of the connecting part 2
A cylindrical inlet part 72 formed integrally connected with the outer tube body 211 of Inside 72 is the entrance chamber 721 and the exit section 7
An outlet chamber 731 is formed between the three inlet portions 72 . On the other hand, the lid 7 has a pressurizing port 75 in the outlet portion 73.
4 is attached by screwing etc., and the compartment 74 inside the lid 74
1, an exit chamber 731, and an inlet chamber 721 are partitioned by a diaphragm 71. With such a configuration, the tube 7 is
9, if the compartment 741 is pressurized during intake,
The diaphragm 71 is pressed against the inlet portion 72,
When the valve closes, and upon exhalation, the pressure in compartment 741 is released, diaphragm 71 opens and the valve opens. Then, by releasing the pressure to a predetermined positive pressure (for example, 5 cmH ₂ O) during expiration, it becomes possible to apply PEEP therapy to reduce the risk of alveolar collapse. . A connecting port portion 26 is integrally connected to such an exhalation valve 7, for example, by being bent into an L-shape. In the example shown in FIG. 5 and the like, the connecting portion 2 is provided with a handle 28 for hanging. An exhalation discharge pipe 4 and an inhalation introduction pipe 5 are connected to the connection ports 26 and 27 of such a connection part 2, respectively. It is preferable to use bellows tubes for both the exhalation discharge pipe 4 and the suction introduction pipe 5 from the viewpoint of preventing collapse due to kinking, but other than that, there are no particular restrictions. Therefore, the inner tube and outer tube of the double tube 1 can be made of normal materials and dimensions as mentioned above.The length of each tube is generally 60 cm to 60 cm.
It is said to be around 120cm. Such exhalation discharge pipe 4 and intake intake pipe 5 are as follows:
The exhalation discharge pipe 4 is connected to the connecting portion 2 through the connecting ports 26 and 27, respectively.
It is preferable that the exhalation valve side of this connection port portion 26 be connected to the exhalation valve 7 in a detachable manner. That is, as shown in FIG. 6, the exhalation valve 7 has a socket 26' for the connection port 26,
It is preferable that the socket 26' and the connection port 26 be connectable by tapered fitting. In this way, the connection port 26 to which the exhalation discharge pipe 4 is connected can be detachably connected to the exhalation valve 7, so that when the exhalation discharge pipe 4 is removed from the exhalation valve 7, the ventilation meter can be adjusted. It can be used as a circuit for unnecessary inhalation therapy, and a small ventilation meter can be connected to the exhalation valve 7.
This means that it can be used even with respirators that do not have a ventilation meter inside the respirator, providing excellent versatility and a simple structure. Specific Effects of the Invention When performing mechanical artificial respiration or inhalation therapy using the breathing circuit of the present invention, for example, connectors are connected to the exhalation discharge pipe 4 and the inhalation introduction pipe 5, respectively.
Connect C ₆ and C ₇ , or remove the exhalation discharge pipe 4 from the exhalation valve 7 of the connecting part 2 as necessary,
Connect to respirator R, anesthesia machine, etc. via a heating humidifier or exhalation flow meter. Further, an L-shaped connector _C5 , for example, is connected to the connector 3, and connected to a tracheal catheter, a mask, etc. on the patient side. In this way, the inspiratory gas sent from the respirator or anesthesia machine is transferred to the inspiratory introduction pipe 5.
The liquid passes through the nebulizer 6 and is sent to the patient from the inner tube 15. Further, exhaled gas from the patient passes between the inner tube 15 and the outer tube 11, passes through the exhalation valve 7, and then enters, for example, the exhalation discharge pipe 4 and is discharged. Specific Effects of the Invention The breathing circuit of the present invention has an extremely simple and compact structure as a whole. In particular, since the area near the patient's mouth has a double tube structure, handling is extremely simple and does not cause any inconvenience to the patient. Moreover, since it has the exhalation valve 7 and the nebulizer 6, there are no limitations on the types, specifications, etc. of usable respirators. In addition, it has the versatility of being used for mechanical ventilation, inhalation therapy, and even anesthesia. Furthermore, since there is a double pipe structure between the connecting part and the patient, there is little heat loss. Therefore, the heating temperature of the intake gas can be lowered, the amount of water stored in the circuit is reduced, and the risk of the patient inhaling high-temperature gas is also reduced. In addition to exhibiting these excellent effects, in the present invention, the double tube structure is provided only between the connecting portion and the patient, so that the effect of reducing inhalation and exhalation resistance is achieved. In this case, as is clear from the experimental examples below,
Compared to a double-tube structure between the patient and the respirator, the inspiratory and expiratory resistances are significantly reduced while keeping heat loss equally low. In addition, the tube diameter that exhibits equivalent inspiratory and expiratory resistance becomes significantly smaller, and the effect that the double tube 1 becomes more compact is achieved. According to the embodiment described above, if both the exhalation discharge pipe and the intake intake pipe are bellows pipes,
Collapsing due to kinking is reduced, improving safety and ease of handling. Embodiment), the outer tube of the double tube is an exhalation tube,
If the inner pipe is used as an intake pipe, it is extremely advantageous in terms of heat loss. Embodiment) If a double portion is provided in the connecting portion as shown in FIG. 7, the structure will be extremely simple. According to the embodiment), if the outer tube is a bellows tube,
There will be less crushing due to kinking. According to the embodiment), if the connection port to which the exhalation discharge pipe is connected can be detachably connected to the exhalation valve, when the exhalation discharge pipe is removed from the exhalation valve, inhalation therapy that does not require a ventilation meter can be performed. In addition, it is possible to connect a small ventilation meter to the exhalation valve, and it can be used even with respirators that do not have a ventilation meter inside the respirator, making it highly versatile. increases, and the overall structure becomes extremely simple. If the connector is connected to the outer pipe and the inner pipe according to the embodiment), the amount of mechanical dead space due to the elongation of the circuit is reduced, and a more favorable result is obtained. Various experiments were conducted to confirm the effects of the present invention. An example is shown below. Experimental example Figure 1 (Comparison 1 below), Figure 2 (Comparison 2 below),
Three types of comparison circuits shown in FIGS. 3 and 4 (comparison 3 below) and the following circuits of the present invention shown in FIGS. The other end was connected to a simulated lung maintained at a temperature of 37°C and a relative humidity of 100%, and the characteristics of each circuit were evaluated. In this case, in the breathing circuit of the present invention shown in FIGS. 5 to 8, the inner tube 1 constituting the double tube 1 used is
5, trough inner diameter 13.5mm, peak inner diameter 15mm, total length
A 60 cm polyethylene bellows tube was used, and this inner tube 15 was used as the outer tube 11 constituting the double tube 1.
A polyethylene bellows tube with the same length as that of 23.5 mm and 28 mm in inner diameter at the crest was used. In addition, each exhalation discharge pipe 4 has a single-pipe structure.
and the inner diameter of the valley part of the intake introduction pipe 5, respectively.
A polyethylene bellows tube with a length of 23.5 mm and an inner diameter of 28 mm and a length of 60 cm was used. On the other hand, in each comparative breathing circuit (comparisons 1, 2, and 3) shown in FIGS. 1, 2, 3, and 4, the outer tube and The inner tube and each tube in the case of a single tube structure were made to have approximately the same tube cross-sectional dimensions as the corresponding tubes in the breathing circuit according to the present invention described above. Further, in each of these three types of comparative breathing circuits, the total length of the tube portion was 120 cm, which was made to match that of the above-mentioned breathing circuit belonging to the present invention. As described above, the present invention or a total of 4 for comparison
For each type of breathing circuit, the respirator was operated for 2 hours while the inspiratory gas was heated and humidified with a heating humidifier under the conditions shown in Table 1 below. The temperature (°C) at the mouth of the simulated lung after the respirator was operated for 2 hours is shown in Table 1 below. Also, the amount of water stored in the circuit per unit volume after operating the respirator for 2 hours (g/
m ³ ) was measured. The results are shown in Table 1 below. In this case, except for Comparison 2 as shown in FIG. 2, the amount of stored water was measured separately between the heating humidifier connection section and between the connection section and the simulated lung. These results are shown in Table 1 below. Furthermore, for each of the four types of breathing circuits mentioned above,
Expiratory resistance (cm) when the flow rate is 30/min
H ₂ O//sec) and inspiratory resistance (cmH ₂ O//
sec) was measured. The results are also listed in Table 1 below.

【表】表１に示される結果から、本発明の回路が総合
的にみて、きわめてすぐれていることがわかる。[Table] From the results shown in Table 1, it can be seen that the circuit of the present invention is extremely superior overall.

[Brief explanation of drawings]

第１図および第２図は、それぞれ、従来の呼吸
回路を説明するための模式図である。第３図およ
び第４図は、本発明者が先に提案した呼吸回路を
説明するための図であり、このうち第３図が正面
図、第４図が第３図の部分拡大平面図である。第
５図〜第８図は、本発明の実施例を説明するため
の図であり、このうち、第５図が、組立て前の状
態にて、一部を断面にて示す正面図、第６図が一
部を断面にて示す第５図の平面図、第７図が連結
部の拡大断面図、第８図ａがコネクタの一部を断
面にて示す正面図、第８図ｂが第８図ａの左側面
図、第８図ｃが第８図ａにて、その中心軸図示一
点鎖線を中心に45゜回転したときの、その半分を
断面にて示す図である。１……二重管、１１……外管、１５……内管、
２……連結部、２１……二重部、２１１……外側
管体、２１５……内側管体、２６，２７……接続
口部、３……コネクタ、３１……給排気口、３３
……外管取付口、３４……内管取付口、６……ネ
ブライザー、７……呼気弁。 FIGS. 1 and 2 are schematic diagrams for explaining conventional breathing circuits, respectively. 3 and 4 are diagrams for explaining the breathing circuit previously proposed by the present inventor, of which FIG. 3 is a front view and FIG. 4 is a partially enlarged plan view of FIG. 3. be. 5 to 8 are diagrams for explaining the embodiment of the present invention, of which FIG. 5 is a front view partially cut away in a state before assembly, and FIG. 5 is a plan view showing a part of the connector in cross section, FIG. 7 is an enlarged sectional view of the connecting part, FIG. 8 a is a front view showing a part of the connector in cross section, and FIG. FIG. 8A is a left side view of FIG. 8A, and FIG. 8C is a cross-sectional view showing half of FIG. 1...double pipe, 11...outer pipe, 15...inner pipe,
2...Connection part, 21...Double part, 211...Outer pipe body, 215...Inner pipe body, 26, 27...Connection port part, 3...Connector, 31...Intake/exhaust port, 33
...Outer tube attachment port, 34...Inner tube attachment port, 6...Nebulizer, 7...Exhalation valve.

Claims

[Claims] 1. It has a double pipe consisting of an outer pipe and an inner pipe,
Connecting a connector having an air supply/exhaust port to one end of the double tube on the patient side, and connecting the other end of the double tube to a connecting portion having a nebulizer and an exhalation valve,
In the connection part, the nebulizer is communicated with one of the outer tube and the inner tube, and the exhalation valve is communicated with the other of the outer tube and the inner tube, and the connection port part communicates with the nebulizer of the connection part. 1. A breathing circuit characterized in that an inhalation introduction pipe is connected to the connecting part, and an exhalation discharge pipe is connected to a connection port part of the connecting part communicating with an exhalation valve independently of the inhalation introduction pipe. 2. The breathing circuit according to claim 1, wherein the exhalation discharge pipe and the intake intake pipe are bellows pipes. 3. Claim 1 or 2, wherein the outer pipe constituting the double pipe is an exhalation pipe and the inner pipe is an intake pipe.
Breathing circuit as described in Section. 4. The connecting part has a double part consisting of an outer pipe and an inner pipe, and a nebulizer is provided so as to communicate with the inner pipe of the double part, and a connection port communicating with the nebulizer is provided. An exhalation valve is provided so as to communicate with the outer tubular body of the double portion, and a connection port portion that communicates with the exhalation valve is provided, and an outer pipe of the double portion of the connection portion is provided with an exhalation valve that communicates with the outer pipe body of the double portion. 4. The breathing circuit according to claim 3, wherein an outer tube and an inner tube are connected to the ends of the tube body and the inner tube body, respectively. 5. The breathing circuit according to any one of claims 1 to 4, wherein the outer tube constituting the double tube is a bellows tube. 6. The breathing circuit according to any one of claims 1 to 5, wherein the connection port to which the exhalation discharge pipe is connected is detachably connectable to the exhalation valve. 7. The connector has an outer tube attachment port and an inner tube attachment port that communicate with the supply/exhaust port, respectively, and the outer tube and inner tube of the double pipe are connected to the outer tube attachment port and the inner tube attachment port, respectively. A breathing circuit according to any one of claims 1 to 6.