人類有阻塞性睡眠呼吸中止症 (OSAS)，也就是睡著時，呼吸道發生阻塞或塌陷，造成頻繁的缺氧，而這在犬隻身上也會發生。狗狗版的類似疾病叫作 BOAS（唸起來像「波哇斯」）。人類和狗狗的呼吸中止症，兩者有什麼不同？又有哪些相似呢？
In humans, obstructive sleep apnea syndrome (OSAS) refers to a medical condition in which the airways become blocked or collapse while asleep, causing frequent oxygen desaturation. The canine version of the sleep-related breathing disorders is "BOAS". What is the difference between sleep apnea in humans and dogs? And is there a similarity between them?
BOAS是「短顱阻塞性氣道症候群」的英文縮寫，是英國鬥牛犬、法國鬥牛犬、巴哥、查理士王小獵犬、吉娃娃、博美...... 這些短顱犬種好發的阻塞性呼吸疾病。網路上有很多這些狗狗站著打瞌睡、鼾聲如雷的影片，看起來很可愛，但其實狗狗是處在一種痛苦呼吸的狀態。可以說牠們醒著就一直是在費力呼吸。
BOAS is the abbreviation of "Brachycephalic Obstructive Airway Syndrome", which is an obstructive respiratory disease that affects dog breeds such as British bulldogs, French bulldogs, pugs, Cavalier King Charles Spaniels, Chihuahua and Pomeranians. There are shorts and videos trending on the Internet that feature the dogs dozing off while eating, and snoring loudly. They look cute, but in fact, the dogs are striving for breathing; they are having stridor even while they are awake.
會發生BOAS，第一個原因是口鼻距離很短，呼吸道窄小。由於寵物犬源自人為挑選想要的特徵去配種，想像一下把狼犬的器官構造，壓縮成外觀小巧的狗，那麼原來的器官構造勢必會大幅度的壓縮，頭骨被壓縮，原本的鼻吻部也被推入面部構造，鼻道、喉嚨的空間被擠壓，神經也被擠壓，最明顯的例子就是鬥牛犬、巴哥。
The major cause of BOAS is shortened muzzle and the narrowing of the respiratory tract of these dogs. Since pet dogs are artificially selected for breeding with desired characteristics; just imagine what happens when you compress the structure of a wolfdog into a small dog, the organs and space for each structure will inevitably be greatly compressed--the skull will be compressed, resulting in a flattened or “pushed-in” facial conformation. The nerves are also "squeezed" to fit into the structure. The most obvious examples are bulldogs and pugs.
上呼吸道內的軟組織結構，由於無法完全適合縮短的顱骨，因此被擠壓並堆積在較小的骨結構內，並可能阻塞氣道。這成了BOAS的第二個原因。
The soft tissue structures within the upper airways have not adapted structurally with the shortening of the skull, and therefore are squashed and packed within the smaller bony structures, and can block the airways, which leads to BOAS.
有些英國鬥牛犬天生軟顎很長，直接深入聲門，迫使這些狗狗必須站著睡覺，或睡覺時要咬著東西，下巴靠在東西上，或頭掛在東西上，因為這樣的姿勢才能強迫呼吸道打開，牠們才能呼吸。
Some English bulldogs are born with a very long soft palate, which goes deep into the glottis. This condition forces them to remain standing or bite something while trying to get sleep; they also like to lean their chin on something, or hang their head on something, because by doing so they can force opening their airways so they can breathe.
也許你會納悶，有些小型犬看起來是有鼻子的呀？但這些狗狗的頭顱很短，鼻吻和鼻咽部的空間還是十分狹小，這會造成查理士王小獵犬常見的鼻中隔彎曲。而吉娃娃的後鼻孔則是超級小，直徑只有 1 mm，只要有一滴水滴塞住就足以造成窒息。
Maybe you are wondering "But some small dogs do have nose, aren't they?" However, the shortened skulls of these dogs allow limited space in the nostrils and nasopharynx. Nasal septum deviation is common in King Charles Spaniels. Chihuahua's posterior nostrils are extremely small, only 1mm in diameter; a drop of water blocking it is enough to cause suffocation.
犬隻的BOAS和人類的OSAS (睡眠呼吸中止症) 病灶在解剖構造上相似，都是在舌根、軟齶處發生阻塞，其次是鼻道的狹窄或阻塞。而OSAS對人的健康造成的影響，同樣也在狗狗身上看到，包括心血管疾病風險升高、腦神經退化、以及壽命減短等等。
The anatomical structures of BOAS in dogs and OSAS (sleep apnea) in humans are similar. They both cause obstruction at the tongue base and soft palate, followed by narrowing or congestion of the nasal airway. The health impact of OSAS on humans is also seen in BOAS dogs, including increased risk of cardiovascular disease, neurodegeneration in the brain, and shortened life span.
相較於小型動物平均有15、16年壽命，BOAS狗狗平均壽命至少短了三年，有BOAS的英國鬥牛犬平均壽命約6～8年。從腦波記錄到的結果也發現，BOAS影響的犬隻有低β高δ波，類似於人類較低IQ者的腦波。
Compared with the average lifespan of small animals, which is 15 or 16 years, the average lifespan of dogs with BOAS is at least three years shorter. The average lifespan of British bulldogs with BOAS is about 6 to 8 years. The recorded brain waves also revealed that dogs affected by BOAS have low beta and high delta waves, similar to the brain waves of humans with lower IQ.
人與犬最大的不同在於，犬隻是「半腦睡眠」，也就是左右腦輪流睡眠，所以牠們睡著時的肌肉張力不像人類一樣會下降很多。
The biggest difference between humans and dogs is that dogs have "unihemispheric sleep", that is, one cerebral hemisphere sleeps while the other is awake, so their muscle tone does not drop as much when they are asleep as humans do.
人類的睡眠呼吸中止症其中一種類型是和「塌陷」(collapsibility) 有關，也就是睡著時，因為肌肉鬆弛，不足以維持氣道打開的張力（像帳篷塌了一樣），導致呼吸道塌陷和狹窄。這類患者沒有呼吸道組織肥厚、身材也不胖，治療上可能就不太能靠手術來改善了（呼吸道空間本來就足夠、也沒有多餘的組織可以清除）。
One type of sleep apnea in humans is related to "collapsibility", that is, when the muscles are relaxed during sleep but to an extent that they are not enough to keep the airway open, resulting in the collapse of the airway (like a collapsed tent). Such patients may not have hypertrophy of respiratory tissue and are not obese, so it's impractical to try surgical management (the respiratory space is already sufficient and there is no excess tissue to remove).
犬隻的BOAS是結構上的阻塞為主，因此外科治療為首選，這包括鼻甲減積、軟齶打薄等方式來改善呼吸。副作用是手術會影響到喉小囊（位於聲帶前方兩側喉壁），叫聲可能會變粗、變低沉，但不影響吞嚥和生活功能。
Since BOAS is mainly caused by structural obstruction, surgical treatments are the first choice, including turbinate debulking and soft palate thinning, to improve breathing. The side effect is that the laryngeal saccules (air sacs located between the vocal folds and laryngeal wall) might be affected by the surgery, which causes hoarseness or deeper voice, although this does not affect swallowing and daily functions.
藥物治療最常用血清素(serotonin)製劑，其治療原理，目前推測是由於血清素能使肌肉張力升高，因此有助於提升呼吸道打開的肌肉張力，降低呼吸中止的嚴重度。
The most commonly used drug treatment is serotonin preparations. The therapeutic mechanism is currently speculated to be that serotonin can increase muscle tone, thereby helping to keep the airway open and reducing the severity of apnea.
人們也觀察到BOAS狗狗常會有「無聲逆流」(silent regurgitation)引起的作嘔反應，（跟人類睡眠呼吸中止伴隨反射性的嗆咳很像）。無聲逆流是因為上食道、下食道跟幽門括約肌鬆弛，造成胃液和胰液由腸胃道進入食道。由於血清素也有止吐功能，可以讓狗狗不會因為反覆嗆咳而打斷睡眠。不過犬隻BOAS的治療仍是以外科手術為主，藥物治療的機轉和療效尚不明確。
It has also been observed that dogs with BOAS often have "gags" caused by "silent regurgitation" (much like the choking/coughing associated with sleep apnea events in humans). Silent regurgitation occurs due to weakened sphincter muscles in the esophagus (the upper and lower esophageal sphincters) and pyloric sphincter, causing gastric juice and pancreatic juice to enter the esophagus from the gastrointestinal tract. Since serotonin also has anti-emetic properties, it can prevent disrupted sleep caused by repeated gagging. However, the treatment of BOAS is still mainly surgical, and the mechanism and efficacy of drug treatment are still unclear.
𓇢𓏸𓏹𓏏
今年的睡眠年會聽了一場很可愛的講座，（因為有很多可愛狗狗的影片），但是也覺得這樣的狗狗很可憐，光是呼吸就這麼辛苦，人類還覺得這樣很可愛。
其實𝐺𝑜𝑜𝑔𝑙𝑒 關鍵字 𝐁𝐎𝐀𝐒 可以很輕易查到資料，但我覺得沒有在養那種狗的，也許也不知道這種事，或是有在養，但不在意。
——人類只為了自己喜歡可愛寵物，到底對狗做了什麼事啊
｡ﾟ꒰ ﾟஇ‸இﾟ꒱｡ﾟ
希望不要再有人養這種狗了。沒有商機，就不會有人培育。對吧？
ꕀ 其他零碎的筆記：
⚚ ⸝⸝ 舌頭伸出來跟睡眠呼吸沒有太大的關係，跟神經系統問題比較有關。
⚚ ⸝⸝ 貓咪有時也會張口呼吸，大部分是鼻孔的問題，不像𝐁𝐎𝐀𝐒狗狗是鼻道和軟顎阻塞。
＊
I wonder if the domestication of the dog is another choreographed confusion of real farce conducted by human beings.
狗的馴化是否又是人類所做出來的另一場真實鬧劇，內含精心設計的混亂。
𓇢𓏸𓏹𓏏 ⋈ . .
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