难经曰伤寒之脉阴阳俱盛而紧涩○伤寒论云脉阴阳俱紧者名曰伤寒○寸口脉浮而紧浮则
为风紧则为寒○浮涩而紧为伤寒
小儿伤寒与大人无异所以异者兼惊夹食而已其七十二证某证某方皆无越张朱格例特不过
小小
之分剂中病则止按仲景伤寒论云春气温和夏气暑热秋气清凉冬气凛烈此四时正气之序也惟冬
时严寒去寒就温不至于伤偶然触冒名为伤耳若冬月冒寒伏藏于肌肤而未即病至春而发者谓
之温病至夏而发者谓之热病至此则伏寒各随春夏
之气改变为病既久之后不得复言其寒也故曰温病不恶寒者其理可见矣如春应暖而反寒夏应热
而反冷秋应凉而反热冬应寒而反温非其时而有其气此四时乖戾之气也偶即中伤谓之时气又与
伤寒不同若小儿在襁褓中或长成而禀赋怯弱多因乳母解脱衣服不避风寒所致也在大人则知其
六经所受之证或三阳传尽次入三阴或始终只在一经或越经或间经或传至一二经而止或不从阳
经而直中阴经者皆可据脉证而辨治之然小儿患此口不能言其致病之由脉不能诊其必然之理但
只烦啼发热而已故不可不尽心焉初得之时婴幼则以虎口指纹之红色验之长而童稚则以一指按
其三关据左手人迎之紧盛而断之钱氏云男体重面黄女面赤喘急憎寒其心气热呵欠烦闷项急者
是也其恶寒恶风必偎人藏身引衣密隐是为表证恶热内实者必出头露面扬手掷足烦渴燥粪掀衣
气粗是为里证至若头额冷汗手足凉口中冷气面色黑黯淡大便泻青此为阴证或视其小便或赤或
白可以知里热之有无或清或浊可以知里热之轻重举是观之则汗下温之可以类推矣
《难经》说：伤寒的脉象，阴脉和阳脉都盛大且紧涩。○《伤寒论》说：脉象寸关尺三部（阴阳）都紧的，称为伤寒。○寸口脉浮而紧，浮主风邪，紧主寒邪。○脉象浮、涩而紧，是伤寒的表现。
小儿患伤寒与成人没有不同，所不同的只是兼夹惊风和食积罢了。那七十二种证候及其对应的方剂，都不超出张仲景、朱肱等人的法度，只不过剂量稍小而已。药力达到病所就停药。按照张仲景《伤寒论》的说法：春天气候温和，夏天气候暑热，秋天气候清凉，冬天气候凛冽，这是四时正常的气候顺序。只有冬季严寒，人们为了避寒就温，不至于受伤；偶然触冒风寒，才叫做“伤”。如果在冬天感受寒邪，潜伏在肌肤之中而没有立即发病，到了春天发作的，叫做“温病”；到了夏天发作的，叫做“热病”。到了这个时候，潜伏的寒邪已经随着春夏的气候改变而转化为其他病症，时间久了就不能再说是寒邪了。所以说“温病不恶寒”，其中的道理由此可见。如果春天应该温暖却反而寒冷，夏天应该炎热却反而凉爽，秋天应该凉爽却反而炎热，冬天应该寒冷却反而温暖，这种非其时而有其气的现象，叫做四时乖戾之气。偶然中伤这种邪气，叫做“时气”，这又与伤寒不同。
至于小儿在襁褓中，或者长大后禀赋怯弱，多是因为乳母解开衣服，不注意避风寒所致。对于成人，可以知道六经受邪的证候，有的从三阳经传遍后次入三阴经，有的始终只在一经，有的越经传变，有的隔经传变，有的传到一或二经就停止，有的不从阳经传变而直接中于阴经，这些都可以依据脉象和证候来辨别治疗。然而小儿患病，口不能言明致病原因，脉象也不能完全诊察出必然的道理，只是表现为烦躁啼哭、发热而已。所以医者不可不尽心诊治。刚患病时，婴幼儿可以通过观察虎口指纹的颜色来验证，年龄稍长的儿童则可以用一根手指按压其食指三关。根据左手人迎脉（此处指寸口脉前部或特定切脉部位，古法有异，此处依原文直译）的紧盛程度来判断。钱乙（钱氏）说：男孩身体重、面色黄，女孩面色赤、喘急、怕冷，打哈欠、烦躁闷乱、项强，这是心气热的表现。那些怕冷、怕风，一定偎依在人怀里，藏身缩体，裹紧衣服的，是为表证。怕热、里有实邪的，一定伸出头脸，扬手掷足，烦躁口渴，大便干燥，掀开衣服，呼吸粗重，是为里证。至于额头出冷汗，手足凉，口中呼出冷气，面色黑而黯淡，大便泻下青色粪便，这是阴证。或者观察其小便，颜色红或白，可以知道里热有无；清或浊，可以知道里热的轻重。举这些例子来看，汗法、下法、温法等治疗手段就可以类推了。
The *Nan Jing* (Classic of Difficult Issues) states: In cold damage, both the Yin and Yang pulses are vigorous and tight and choppy. ○ The *Shanghan Lun* (Treatise on Cold Damage) states: When the pulse is tight in both Yin and Yang aspects, it is named cold damage. ○ At the Cun Kou (Inch Port) position, if the pulse is floating and tight, floating indicates wind, and tight indicates cold. ○ A pulse that is floating, choppy, and tight indicates cold damage.
Pediatric cold damage is no different from that in adults; the only difference lies in the concurrent presence of fright and food retention. The seventy-two syndromes and their corresponding formulas do not exceed the principles established by Zhang Zhongjing and Zhu Gong, differing only in dosage being slightly smaller. Treatment should cease once the medicine reaches the disease site. According to Zhang Zhongjing's *Shanghan Lun*: Spring climate is mild, summer climate is hot and humid, autumn climate is cool, and winter climate is severe and biting. This is the normal sequence of the four seasons' righteous Qi. Only in winter, when it is severely cold, do people seek warmth to avoid injury; accidental exposure to wind and cold is termed "injury." If cold pathogen is contracted in winter, lying latent in the skin and muscles without immediate onset, and manifesting in spring, it is called warm disease (Wen Bing); if it manifests in summer, it is called heat disease (Re Bing). By this time, the latent cold has transformed into other diseases following the Qi of spring and summer, and after a long duration, it can no longer be referred to as cold. Thus, it is said that "warm disease does not involve aversion to cold," which reveals the underlying principle. If spring should be warm but is instead cold, summer should be hot but is instead cool, autumn should be cool but is instead hot, and winter should be cold but is instead warm, this phenomenon of having the Qi of one season at the wrong time is called the aberrant Qi of the four seasons. Accidental contraction of such pathogens is called seasonal Qi (Shi Qi), which differs from cold damage.
As for infants in swaddling clothes or older children with weak congenital constitution, the cause is often due to wet nurses exposing themselves to wind and cold by loosening clothing. For adults, one can identify the syndromes of the Six Channels (Liu Jing): some transmit through the Three Yang channels before entering the Three Yin channels; some remain in a single channel throughout; some skip channels (Yue Jing); some transmit across channels (Jian Jing); some stop after transmitting to one or two channels; and some bypass the Yang channels to directly strike the Yin channels. These can all be differentiated and treated based on pulse and syndrome. However, pediatric patients cannot verbalize the cause of illness, and the pulse may not fully reveal the inevitable pathology, presenting mainly as irritability, crying, and fever. Therefore, physicians must exert utmost diligence. Upon initial onset, infants are examined via the redness of the fingerprint at the Tiger's Mouth (Hu Kou), while older children are assessed by pressing the three segments (San Guan) of the index finger with one digit. Judgment is made based on the tightness and fullness of the Ren Ying pulse (here referring to a specific palpation site or aspect of the radial pulse) on the left hand. Qian Yi (Qian Shi) stated: Boys presenting with heavy body and sallow complexion, girls with reddish face, panting, rapid breathing, and aversion to cold, along with yawning, irritability, restlessness, and neck stiffness, indicate Heat in Heart Qi. Those who fear cold and wind, clinging to others, hiding their bodies, and tightly wrapping themselves exhibit exterior syndromes. Those who fear heat and have interior excess, protruding their heads and faces, flinging arms and legs, experiencing irritability, thirst, dry stools, pushing away covers, and coarse breathing, exhibit interior syndromes. Conversely, cold sweat on the forehead and temples, cold hands and feet, cold breath, dark and dull facial complexion, and green loose stools indicate Yin syndromes. Observing urine, whether red or white, reveals the presence or absence of interior heat; whether clear or turbid indicates the severity of interior heat. From these observations, methods such as diaphoresis (sweating), purgation, and warming can be inferred.