删繁论曰∶夫三焦者，一名三关也，上焦名三管，反射中焦名霍乱。下焦名走哺，合而
为一，有名无形，主五脏六腑往还神道，周身贯体，可闻不可见，和利精气决通水道息气脾
胃之间，不可不知也，凡上焦三管反射者，通三焦名中清之腑也，别号玉海水道出属膀胱合
者虽合而不同，上中下三焦同号为孤之腑也，而营出中焦，卫出上焦。（营者是络脉之气道
卫者是经脉之气道也）上焦如雾，（雾者霏霏起上也）起于胃上管并咽以上，贯膈布胸中，
走
腋，循足太阴之分而行还注手阳明，上至舌，下注足阳明，常以营卫俱行于阳二十五度，行
阴亦二十五度为一周，日夜五十周身，周而复始，大会于手太阴，手少阳也，主心肺之病，
内而不出，人有热则饮食下胃，其气未定，汗则出，或出于面，或出于背，或出于身手，皆
不循卫气之道而出，盖外伤于风内开腠理，毛蒸理泄，卫气走之，故不得循其道，此气剽悍
滑疾，见开而出，故不得其道，名曰∶漏泄。其病则肘掌痛，食先吐而后下，气不续胸膈间
厌闷，所以饮食先吐而后下也，寒则精神不守，泄下便利，语声不出，若实则上绝于心若虚
则引气于肺。（出第四卷中千金同）
千金论曰∶三焦病者腹胀气满，少腹尤坚，不得小便窘急，溢则为水，留则为胀，候在
足太阳之外，大络在太阳少阳之间，亦见于脉，取委阳少腹病肿痛，不得小便，邪在三焦，
约取太阳大络，视其结脉，与厥阴小络结而血者，三焦胀者，气满在皮肤，壳壳然而不坚手
少阳之脉，是动则病耳聋， ，嗌肿喉痹是主气所生病者，汗出，目锐 痛，颊痛，
耳后肩 肘臂外皆痛，小指次指不用为此诸病。寒则留之，热则疾之陷下则灸之，不盛不虚
以经取之盛者人迎一倍于寸口虚者人迎反小于寸口。（出第二十卷中）
《删繁论》说：三焦，又名三关。上焦称为“三管”，其气反射至中焦则表现为霍乱。下焦称为“走哺”。三者合而为一，有名而无形，主宰五脏六腑之间神气的往来，贯通全身，只能感知其功能而不能看见其实体。它调和精气，疏通水道，调节脾胃之气，这些道理是不可不知的。
凡是上焦“三管”反射的情况，统称为三焦，它是中清之腑（指含有清稀津液、不直接传化水谷的脏腑）。另有别号叫“玉海”，水道由此而出，归属于膀胱。虽然上下中三焦名称相同，但都被称为“孤腑”（独一之腑）。其中，营气产生于中焦，卫气产生于上焦。（所谓营气，是行于络脉中的气；所谓卫气，是行于经脉中的气。）
上焦的功能像雾露一样弥漫。（雾者，形容雾气霏霏向上蒸腾的样子。）上焦之气起于胃的上部，沿着咽喉向上，穿过膈肌，散布于胸中，走向腋下，沿足太阴脾经的分野运行，然后回流注入手阳明大肠经，上行至舌根，向下注入足阳明胃经。营气和卫气通常共同在阳分运行二十五周，在阴分也运行二十五周，构成一个循环。昼夜共运行五十周于全身，周而复始，最终大会于手太阴肺经和手少阳三焦经。
上焦主要主管心肺的疾病。如果病邪在内而不外达，人体有热时，饮食进入胃中，其精气尚未完全化定，汗液就会流出。有的从面部出，有的从背部出，有的从手部或脚部出，这些都是没有遵循卫气正常运行的道路而流出的。大概是因为外伤风邪，导致腠理（皮肤纹理及汗孔）张开，体内热气蒸腾，腠理泄开，卫气随之流失。因为卫气性质剽悍滑疾，遇到腠理开张就外出，所以不能循其正道，这种情况被称为“漏泄”。
这种病的症状包括肘部和手掌疼痛，进食后先呕吐然后再下行，气息不畅，胸膈间感到压抑闷胀，这就是饮食先吐而后下的原因。如果属寒证，则精神不能守舍，出现腹泻和大便通畅，声音发不出；如果属实证，则气逆上绝于心；如果属虚证，则引动肺气。（出自《千金方》第四卷，与此处记载相同。）
《千金方》论述说：三焦发生病变，会出现腹部胀满，小腹部尤其坚硬，小便不通畅且急迫。如果水液溢出则为水肿，停留体内则为胀满。诊察部位在足太阳膀胱经之外侧，大络位于太阳经和少阳经之间，脉象上也能观察到。治疗应取委阳穴。如果是小腹部疾病肿痛，小便不通，这是邪气在三焦，应当选取太阳经的大络，观察其结聚的脉象。如果有厥阴经的小络结聚且有瘀血，也应处理。
三焦胀病，表现为气满于皮肤之下，叩之空空然而不坚实。手少阳三焦经的经脉发生变动，会引发耳聋、咽喉肿痛、喉痹等病症。该经主司气机所生的疾病，症状包括出汗、目外角疼痛、脸颊疼痛、耳后、肩部、肘部、手臂外侧均疼痛，无名指和小指活动不利。对于这些疾病，寒证用留针法（久留针以温补），热证用疾刺法（快进快出以泻热），脉象陷下的用灸法，不虚不盛的按本经取穴。实证表现为人迎脉搏动比寸口脉大一倍，虚证则人迎脉搏动反而小于寸口脉。（出自《千金方》第二十卷。）
The *Shanfan Lun* (Treatise on Eliminating Redundancy) states: The Sanjiao (Triple Burner), also known as the Three Passes, has its Upper Jiao referred to as the "Three Tubes." Its qi reflects to the Middle Jiao, manifesting as Huoluan (Cholera-like syndrome with vomiting and diarrhea). The Lower Jiao is called "Zoubu" (Difficulty in feeding/digestion). Together they form one entity, having a name but no distinct form. They govern the往返 (intercourse/communication) of divine qi among the Five Zang and Six Fu organs, penetrating the entire body. Their function can be perceived but not seen. They harmonize essence and qi, unblock water passages, and regulate the qi between the Spleen and Stomach; these principles must not be ignored.
Regarding the reflection of the Upper Jiao's "Three Tubes," this collectively refers to the Sanjiao, which is the "Middle-Clear Organ" (a fu organ containing clear fluids, not directly transmitting food residues). It is also nicknamed "Yu Hai" (Jade Sea). The water passage originates here and connects to the Bladder. Although the Upper, Middle, and Lower Jiao share the same general designation, they are all termed the "Lone Organ" (the solitary Fu organ). Specifically, Ying Qi (Nutritive Qi) arises from the Middle Jiao, and Wei Qi (Defensive Qi) arises from the Upper Jiao. (Ying Qi is the qi circulating in the Luo Collaterals, while Wei Qi is the qi circulating in the main Jing Meridians.)
The function of the Upper Jiao is like mist or dew. (Mist refers to the fine vapor rising upwards.) The qi of the Upper Jiao originates from the upper part of the Stomach, ascends along the pharynx, penetrates the diaphragm, spreads in the chest, moves towards the axilla, follows the distribution of the Foot-Taiyin Splein Meridian, returns to inject into the Hand-Yangming Large Intestine Meridian, ascends to the tongue, and descends to inject into the Foot-Yangming Stomach Meridian. Ying Qi and Wei Qi typically circulate together twenty-five cycles in the Yang aspect and twenty-five cycles in the Yin aspect, completing one revolution. Throughout day and night, they circulate fifty times around the body, repeating endlessly, finally converging at the Hand-Taiyin Lung Meridian and the Hand-Shaoyang Sanjiao Meridian.
The Upper Jiao primarily governs diseases of the Heart and Lungs. If pathogens remain internal without exteriorizing, and the body has heat, when food enters the Stomach, its qi has not yet stabilized, sweat will emerge. It may appear on the face, back, hands, or feet. These instances occur because the sweat does not follow the proper pathway of Wei Qi. This is generally due to external wind pathogen invading, causing the Couli (pores/skin texture) to open, internal heat steaming, and the Couli leaking. Wei Qi, being fierce, rapid, and slippery, exits upon seeing the opening, thus failing to follow its correct path. This condition is named "Lou Xie" (Leakage/Sweating disorder).
Symptoms include pain in the elbows and palms, vomiting followed by defecation after eating, shortness of breath, and oppression/stuffiness in the chest and diaphragm, explaining why food is vomited before passing down. In cold patterns, spirit fails to reside, leading to diarrhea and loose stools, and loss of voice. In excess patterns, qi cuts off upward affecting the Heart; in deficiency patterns, it draws qi into the Lungs. (Source: Volume 4 of *Qianjin Fang*, consistent with the text above.)
The *Qianjin Fang* discusses: When the Sanjiao is diseased, abdominal distension and fullness occur, with the lower abdomen particularly hard. There is difficulty urinating, urgency, overflow leading to edema, and retention leading to distension. The diagnostic sign is located outside the Foot-Taiyang Bladder Meridian; the large collateral lies between the Taiyang and Shaoyang meridians, and this is also visible in the pulse. Treatment should select Weiyang (BL39). For lower abdominal disease with swelling, pain, and inability to urinate, where the pathogen is in the Sanjiao, one should select the large collateral of the Taiyang meridian, observing its knotted vessels. If there are knotted small collaterals of the Jueyin meridian with blood stasis, treat them accordingly.
In Sanjiao Distension, qi fills the skin/subcutaneous tissue, sounding hollow upon percussion but lacking firmness. When the Hand-Shaoyang Sanjiao Meridian undergoes change, it causes deafness, throat swelling, and Hou Bi (obstruction of the throat). As the meridian governing Qi-related diseases, symptoms include sweating, pain at the outer canthus of the eye, cheek pain, and pain behind the ear, shoulder, elbow, and lateral arm, with dysfunction of the ring and little fingers. For these diseases, cold patterns require needle retention (Liuzhen); heat patterns require rapid insertion and withdrawal (Jizhi); sinking pulses require moxibustion; neither excess nor deficiency patterns are treated by selecting points from the affected meridian itself. Excess patterns present with the Renying (ST9) pulse beating twice as strong as the Cunkou (Radial) pulse; deficiency patterns present with the Renying pulse weaker than the Cunkou pulse. (Source: Volume 20 of *Qianjin Fang*.)