2019-03-18 編輯 蛇咬傷之後. 應觀察多久. 才能排除毒蛇咬傷?
Up-to-date 上面寫, 無症狀的患者, 如果懷疑是神經性毒蛇咬傷. 應觀察 24 小時 (但急診教科書Rosen第八版寫 6-8 小時)
有輕微症狀(疼痛, 腫脹)觀察 12 小時如果沒有惡化可出院
出血性毒蛇咬傷通常在 12 小時內會出現症狀.
如果當地的毒蛇咬傷會造成全身性肌肉溶解, 建議觀察 24 小時(?), 出院前測量 CK.
最好是讓病患觀察過夜, 不要傍晚或晚上放回家.
Asymptomatic (dry bite) — A significant proportion of snakebites do not result in envenomation. Patients without clinical features of local or systemic envenomation should be closely observed before discharge from medical attention. The time required for observation in hospital before discharge of an asymptomatic patient with possible envenomation depends upon the venom properties of the local snake fauna and the level of clinical and laboratory expertise available [26]. Clinicians who are unfamiliar with the management of snakebite should seek expert consultation with a clinical toxinologist, poison control center, or physician experienced in management of snakebites in the region. (See 'Additional resources' below.)
Important considerations include the following [16,17]:
●Patients with unknown snakebites in regions with neurotoxic snake species may warrant prolonged observation (up to 24 hours post-bite).
●Snake venoms that cause isolated coagulopathy will usually do so within 12 hours after envenomation.
●In locations where snakebite can cause systemic myolysis, observation up to 24 hours and pre-discharge measurement of creatine kinase may be warranted.
●In general, it is wise to observe suspected snakebite patients overnight, rather than discharge them in the evening or at night, as local resources allow.
下面這段是急診的教科書的內容 ROSEN page 801(電子書 908).
Disposition 病患動向. 如果臨床上無明顯中毒跡象, 非毒蛇或蝮蛇, 可觀察 6-8 小時, 但某些毒蛇的毒性可能在 8 小時之後才出現, 如果觀察八小時都沒有出現毒性徵象, 可讓病患離院. 建議給予破傷風疫苗. 傷口處理指引, 約 24-48 小時回診追蹤. 需衛教病患哪些是遲發性症狀, 需回急診評估.
If no envenomation is evident after clinical examination and the snake was either nonvenomous or a pit viper, the victim can be observed for 6 to 8 hours. With some snakebites, however, toxicity may be delayed by up to 8 hours. If no sign of envenomation is seen after 8 hours, the patient may be discharged. These patients require tetanus immunization when indicated, wound care instructions, and referral for follow-up within 24 to 48 hours. They require instructions on the types of delayed symptoms that may occur and when to return to the emergency department.
如果僅有局部疼痛輕微水腫, 可在急診室觀察 12 小時, 如果疼痛及水腫減輕, 無其他全身性症狀, 抽血正常, 可比照無毒蛇咬傷處置, 任何中度至嚴重中毒症狀患者均需住 ICU 觀察, 監視抗毒血清療效, 根據咬傷的嚴重度, 可能需輸血, 給昇壓劑, 侵犯性監測.
If only local pain and minimal edema have occurred, the patient is closely watched for 12 hours in the emergency department. If the pain and swelling decrease and no systemic symptoms or laboratory abnormalities develop, the patient may be treated with the same precautions as a patient with no signs of envenomation. Any patient with moderate or severe envenomation should be admitted to an intensive care unit for monitoring during antivenin therapy. Depending on the severity of the bite, blood products, vasopressors, and invasive monitoring may be necessary.
任何被珊瑚蛇, 響尾蛇(Mojave rattlesnake), 外國進口的蛇咬傷的病患都有嚴重神經後遺症的風險. 在被咬數小時內可能沒有明顯症狀. 因此, 這類病患需住院觀察, 最好住 ICU. 且要備妥其他急救設備(呼吸器,侵犯性監視器, 洗腎設備) . 如果出現症狀要早點給抗毒血清. 有些經驗豐富的醫師可能會等到出現症狀再給抗毒血清, 所有施打抗毒血清的病患都應密切監測凝血功能異常的發生, 這個狀況可能發生於治療數天之後.
Any patient bitten by a coral snake, a Mojave rattlesnake, or an exotic snake is at risk for severe neurologic sequelae that may not become evident for many hours. As a result, these patients require hospital admission, preferably to an intensive care unit where they can be monitored closely. Arrangements should be made to have a ventilator, invasive monitoring, and dialysis equipment available if necessary. Appropriate antivenin should be obtained and treatment initiated at the earliest onset of symptoms. Some experienced clinicians may wait until symptoms develop before administering antivenin. All patients receiving antivenin require close monitoring for recurrence of coagulopathy, which may occur several days after initial envenomation.
急診教科書 Tintinalli's Emergency Medicine 第八版. page 1380
可使用 CONSTRICTION BANDS. 不要使用止血帶. 不管使用哪一種形式, 不可以完全阻斷動脈血流.
2017-11-13 from CDC. 不建議打 tourniquet. 不建議冰敷. 不建議浸水.
2017-09-18 EDIT
毛醫師說
（適用台灣的整理與建議）
對於蛇傷初步處理建議, 我簡化並歸納如下, 供大家參考
1. 在毒蛇易出沒地點工作，宜穿戴防護具如手套或膠鞋，避免肢體外露；
2. 住家、工作場所、或經常通行的步道附近盡量保持乾淨，避免堆放過多物品，避免食物隨處棄置，讓蛇或蛇的獵物---鼠類有躲藏的空間；
3. 夜間走道、廚房應有足夠的照明或使用手電筒，因為許多龜殼花或眼鏡蛇咬傷意外是發生在住家 (廚房) 或院子中 (沒有足夠照明、不小心踩到牠們)；
4. 穿越草叢或樹叢時，避免光腳或打赤膊，最好先以長棍打草驚蛇，驅走毒蛇；
5. 避免伸手到看不見內部狀況的枯木或樹枝堆裡 (例如颱風後要清理枯枝、樹葉等)或石頭、水管縫隙中去清理或移動它們，最好使用輔助工具例如耙子、掃帚來處理等；
6. 若在家中發現蛇類，可以掃把、畚箕跟有蓋垃圾筒，把牠們掃進去並移到野外，牠們可以持續的控制鼠害、減少人類傳染病；
7. 驅蛇物質例如石灰、雄黃、鵝糞等，並未證實有效，蛇在逃命或追逐獵物時，可輕易的越過這些界線而毫髮無傷；
假設不幸發生了蛇傷，也建議簡化的處理流程如下：
1. 嘗試辨認蛇種 (例如綠色---青竹絲、土色帶斑點---龜殼花、黑色---眼鏡蛇，這三種蛇約占了臺灣毒蛇咬傷的80%-90%)，但不要追趕或捕捉牠們，因為這些動作可能會激起毒蛇的攻擊；可使用手機照相、錄影來替代捕捉；即便真的沒有辦法獲知毒蛇種類 (例如夜晚)，也不用過度擔心，請盡快請119協助送醫，併提供醫療人員咬傷情境 (例如睡覺時、爬樹時、除草撿枯枝時、或在廚房浴室中被咬等) 以利專業人員綜合判斷；
2. 目前最有效的毒蛇咬傷治療，就是使用抗蛇毒血清，切莫自行綑綁患肢、切開、吸吮、或塗抹未經證實有效的物質 (例如氨水、精油) 或草藥在傷口上，這樣反而更容易細菌感染；
3. 發生蛇傷後避免喝酒驅毒或跑步追蛇，酒精或運動都有可能會促進血液循環，加速蛇毒的擴散 (特別是神經毒)；
4. 若因工作導致被咬傷肢體被汙染 (例如沾到泥巴、垃圾等)，可考慮先使用清水清洗傷口後再送醫；
5. 至於到醫院前，是否一定要把患肢放低，在臺灣倒是可以不作硬性規定；唯再次強調，蛇傷患者應盡速由專業的 119 救護技術員送醫，他們比較有能力處理急性併發症；
至於是否綁彈砂, 肢體加壓固定等, 說明如下:
1. 前因: ACLS 曾把 constriction band or pressure immobilization 列入蛇傷first aid; constriction band (近心端, 鬆鬆的綁) originated from North America, 主要是對響尾蛇亞科成員使用, 的確可延緩擴散速度; pressure immobilization originated from Australia, 主要是對蝙蝠蛇科成員使用, 也可延緩擴散速度;
2. 臺灣毒蛇能與美洲或澳洲相關成員比擬的, 大概就只有百步蛇與雨傘節(或加上鎖鍊蛇), 但是流行病學青竹絲, 龜殼花, 眼鏡蛇應該佔了至少80-90%的蛇傷病患, 而這些蛇的表現主要是局部組織毒性;
3. 在非洲的文章(主要 Naja spp.) 提及組織毒性時, 再使用這些restriction materials, 有可能會讓蛇毒更局限在local tissues, 會使組織破壞更嚴重;
4. 2011 有六大毒物學會聯合發表聲明(position statement): 不建議PI 使用在美洲的響尾蛇亞科成員咬傷, 衍生出的議題就是其他區域要使用(CB or PI)必須審慎考量 (甚至將這些動物實驗成果推估到人體, 仍然有疑問);
5. 考量臺灣送醫速度極快(以前的研究約30 min, 與北美或澳洲顯然不同), 決大多數是局部毒性應不需使用 restriction materials, 且為了達到CB and PI (有固定的加壓壓力需達成), 可能需花大把的時間精神教導 EMTs, 然而效果存疑(真的有效嗎?);
6. 目前最有效的治療仍然是血清;
7. 所以在缺乏任何本土研究的狀態下, 僅依學理不做此項建議, 希望能簡化到院前的處置, 而個人相信, 考量前述諸多因素後, 清水清洗然後119送醫應該是最好的方法(也能達到盡量縮短延誤的時間);
8. 至於冰敷, 只要不是泡在冰塊內, 或是可能影響肢體末稍perfusion
的狀態, 應該是容許的(但冰敷使用在 sport medicine 時, protocol 各異, 更不用談在毒蛇, 它並沒有一個好的研究設計來比較成效, e.g. pain score);
9. 到院前肢體擺放高度, 個人覺得不影響臺灣蛇傷的處理;
10. 至於拍照一事, 之前看到Dr. Khal 的意見, 可以列為建議, 但是否能算 First aid 仍存疑;
以上
關於蛇咬傷使用彈性繃帶另外整理一篇在這裡 http://blog.xuite.net/ymmcc/twblog/367530817
關於冰敷對蛇咬傷的作用另外整理一篇在這裡 http://blog.xuite.net/ymmcc/twblog/534378820
2017-01-27 snake bite uptodate
下列方式須避免
1. 切開傷口或用嘴巴吸毒
2. 使用器械吸毒 *(毒液能被吸出的比例太低)
3. 冰敷 (可止痛但無法減少毒液散佈) (關於冰敷有另外整理一篇 http://blog.xuite.net/ymmcc/twblog/534378820)
4. 在野外現場手術
5. 電擊治療
6. 止血帶
吸毒能移除的毒素實在非常有限, 在一篇模擬毒素研究發現僅能移除 2% 毒素. 吸毒所使用的負壓可能會傷害到周圍組織, 有可能增強毒素吸收進入組織, 增加局部組織傷害.
(筆記 2017-06-05 毒蛇急救器沒有用)
Methods to avoid — The following methods, while used widely in the past and advocated by some, cause more harm than good and should be avoided :
●Incision and oral suction
●Mechanical suction devices
●Cryotherapy
●Surgery
●Electric shock therapy
●Tourniquets
For example, a common misconception is that one should apply a tourniquet, suck out the poison, and spit it out. However, this approach is strongly discouraged, since it can damage nerves, tendons, and blood vessels and lead to infection. Furthermore, venom removal by suction is minimal. This was illustrated in a study of mock venom extraction with a mechanical suction device in human volunteers; suction reduced the total body venom burden by only 2 percent. In addition, patented local suction devices for snakebite exert significant local negative pressure which can disrupt adjacent tissues and may potentially enhance venom absorption with increased local tissue injury.
Tourniquets may cut off arterial blood flow and cause significant ischemic damage, especially when left on for a prolonged period of time.
2016-10-08 青竹絲
高醫師說：出血性蛇咬傷，以腫為表現，輕微瘀青，腫很快
高醫師說：眼鏡蛇咬傷，牙痕明顯且有明顯瘀血。抗毒血清打了 6支，現在ㄧ律靜脈給藥，神經性ㄧ次以三支為單位
2016-06-25 修改
FROM ROSEN 8th Edition page 797
Management
Out-of-Hospital Care 到院前處置, 有四個重要觀念. 1. 估算到達醫院需多久時間. 2. 盡量減慢毒液散布. 3.辨識毒蛇種類 4. 其他醫療輔助(監視器,靜脈輸液.止痛).
將蛇移開. 將會限制肢體腫脹的戒指或衣物移除, 避免止血帶效應,
減少毒液散布, 病患太亢奮, 運動, 咬傷部位活動, 喝酒, 咬傷越深, 毒液散布速度會越快, 所以要安撫傷患, 固定咬傷部位, 不要給傷患吃東西,
All snakebites are considered an emergency, and any victim should be medically evaluated. The initial 6- to 8-hour period after a snakebite is critical. During this time, medical therapy can help prevent the morbidity associated with severe envenomation. Effective out-of-hospital care can be important. Out-of-hospital care is relatively simple if guided by four basic concepts. First, the estimated time until arrival at a medical facility, as well as the skill of the on-scene assistants, must be considered when first aid is instituted. Separate the victim from the snake if possible to prevent further bites. A stick, pole, or other object longer than the snake can be used to move the snake away from the victim or, if necessary, to kill the snake by striking it behind the head. Rapid transportation to a medical facility is the best first aid for a snakebite. Any constricting jewelry or clothing should be removed from an extremity to prevent a tourniquet effect proximal to the swelling. Second, spread of the venom should be slowed if possible; several methods are known. The patient’s excitement and physical activity, movement of the bitten area, alcohol consumption, and greater depth of the bite may increase the spread of venom. Except for the last factor, these issues can be addressed by calming the victim, immobilizing the bitten area with a sling or splint, and not giving anything by mouth. A method of first aid for venomous snakebites that was developed in Australia—the immobilization and compression technique (also called the Commonwealth Serum Laboratory technique)—slows uptake of Elapidae venom and mock venom (mock viper 茶斑蛇) ) in humans. 可以用彈性繃帶或空氣副木固定受傷肢體 The bitten extremity is either wrapped in an elastic bandage or placed in an air splint. 澳洲發展出另一種技術 Monash method In another technique from Australia called the Monash method, a thick pad and bandage are placed over the bite wound and extremity. Both these techniques have similar postulated mechanisms of action: The lymphatic vessels and superficial veins are collapsed, and the proximal spread of venom is slowed. 對眼鏡蛇咬傷有效果，但對於蝰蛇咬傷尚未證實有效 Although this method is successful as first-aid therapy for Elapidae bites, its use for pit vipers （蝰蛇科）has not been demonstrated. 受傷 30 分鐘內可以使用彈性繃帶纏繞 If less than 30 minutes has elapsed since the bite, a constricting band applied tightly enough to impede superficial venous and lymph flow, but not arterial blood flow, may be used. 繃帶纏繞不要太緊, 要讓一根手指頭可以穿過, 纏繞太緊，當組織更腫脹之後會引起止血帶效應，過度壓迫對組織傷害比蛇毒更大 The band is applied loosely enough to admit a finger between the band and the skin after application. It is used with caution to prevent the development of a tourniquet effect under swollen tissue, which may cause more destruction than the snakebite. 不要切開傷口 Incision of bite wounds has no proven efficacy and poses potential danger to underlying structures and therefore is not recommended. 不要冰敷，無法減緩毒液散播 The use of ice is not helpful in slowing the spread of venom, 但被咬傷部位如果疼痛，可以適當的使用冰敷止痛，冰袋用毛巾包住，皮膚不要直接接觸冰塊 but an ice bag wrapped in a towel and applied to the bite area helps relieve pain. 不要泡冰水危險，會傷害組織 Ice water immersion and packing of the extremity in ice are dangerous and only contribute to tissue destruction. 毒蛇咬傷抽吸器沒有證據顯示有效 The use of suction devices has not been shown to be beneficial.19 Third, when feasible, the snake should be identified or brought to the treating facility with the victim, though this should not delay transport of the patient to definitive medical care. Identification of the snake must be done safely—usually only by someone expert in handling snakes. A photo may be useful in identifying the snake if a close-up of the head and tail are included. Dead snakes can be placed in a hard container, such as a bucket or ice chest. 死掉的蛇還是可能注射出毒液，不要摸蛇頭 Care should be taken to not touch the head of the snake because envenomation can occur even after death. Fourth, additional medical interventions, if available, should
be initiated, including cardiac monitoring, intravenous fluids, and analgesics.
FROM Tintinallis Emergency Medicine A Comprehensive Study Guide, 8th
PREHOSPITAL MANAGEMENT 可以使用彈性繃帶. 固定患肢，在沒受傷肢體建立靜脈管路，給氧，送醫。在給予抗蛇毒血清之前不要移除止血帶或彈性繃帶(存疑，止血帶使用不慎，比蛇毒更慘)
In the prehospital phase, immobilize the limb, establish IV access in another limb, administer oxygen, and transport the victim to a medical facility. Do not remove tourniquets or constricting bands until antivenom is available. Institute advanced life support measures as indicated. If the patient is hypotensive, rapidly administer IV isotonic fluids. Continue to immobilize the limb in a neutral position during transport to reduce further venom absorption. Consult with a physician or poison control center familiar with the management of snake envenomation for most cases.
如果已經出現感染症狀可以使用抗生素. 有些專家建議預防性使用抗生素, 但現有資料不支持例行性使用. 類固醇僅限於過敏反應或血清病使用.
Clean the bite wound and determine the need for tetanus immunization. Obtain wound specimens for culture and administer antibiotics if signs of infection are present. Although antibiotic prophylaxis is recommended by some authors, the data available do not support its use. Steroids are not effective and could be harmful. Steroids should be reserved for the treatment of allergic reactions or serum sickness.
ELAPID SNAKE BITE 眼鏡蛇科咬傷.
FIRST AID 澳洲和新幾內亞(以神經性毒蛇咬傷佔大宗). 會使用彈性繃帶包紮. 原則是將毒液限制在局部, 避免毒液從淋巴系統輸送. 纏繞施予的壓力比照扭傷處力. 不要阻斷動脈血流, 使用夾板將被咬傷的肢體固定. 限制受傷肢體的活動. 走動會加速全身性中毒. 不要使用止血帶. 如果是軀幹被咬傷. 彈性繃帶纏繞軀幹的時候不要影響呼吸. 如果是會造成局部組織損傷的蛇毒. 彈性繃帶纏繞可能加重局部組織受損. 將受傷肢體用副木固定.
眼鏡蛇科咬傷或不明蛇類咬傷（出血性蛇毒，或不明種類），使用彈性繃帶會造成組織受傷變的更嚴重，因此不建議使用彈性繃帶，因此略過彈性繃帶加壓，用副木固定被咬傷部位即可
In Australia and New Guinea, pressure bandaging and immobilization of the involved limb is used. The principle is to contain the venom locally and prevent venom transport by lymphatic vessels. Wrap an elastic bandage firmly over the bite site and then extend it to cover the entire limb (bandage pressure similar to that used for sprains: firm, but not tourniquet tight). Splint the limb to prevent movement, an essential part of the method. Examination of lymphatic flow rates with simulated venom has demonstrated that, even if the upper or lower limb is appropriately bandaged and immobilized, walking will hasten systemic envenoming. Use of tourniquets is contraindicated. In the rare circumstance that a bite is inflicted on the trunk, apply firm pressure to the affected area without restricting breathing. Outside of Australia and New Guinea, the choice of first aid is more nuanced. If the bite is from an elapid(elapid=眼鏡蛇科) that may cause local tissue damage or is from an unidentified snake, then pressure bandaging and immobilization may increase local tissue injury. 略過彈性繃帶加壓，直接用副木固定被咬傷部位 Omit the pressure bandage but splint the bitten part.
毒蛇咬傷並不一定會將毒液注射入我們受傷部位
台灣版的毒蛇咬傷處理，黃嘉勳醫師有提到：儘速以彈性繃帶緊緊包紮患肢，包紮範圍越大越好
http://www.greencross.org.tw/toxin/snake/snake_toxin.htm
林杰樑醫師這篇則是說, 不要使用橡皮筋或其他物質, 阻斷動靜脈血流.
http://www.greencross.org.tw/toxin/prev_snake_bite.htm
蛇咬傷到院前處置 ROSEN 5TH EDITION P 789
1. 安撫傷患，避免情緒激動，可減緩毒性擴散
2. 固定被咬傷部位
3. 保持空腹，不要吃東西
4. 被咬傷處纏繞繃帶減緩血液及淋巴流動（不可阻斷動脈流動）
5. 兩種可以減少淋巴及靜脈血流的方式,可減緩毒液流動向心臟
Commonwealth Serum Laboratory technique，用彈性繃帶纏繞受傷部位 或用 air splint 固定受傷部位。
可減緩 Elapidae venom. Elapidae蝙蝠蛇科=雨傘節 & 眼鏡蛇
Monash method: 在受傷部位使用厚棉墊和繃帶纏繞
對於pit viers 響尾蛇 (蝰蛇科)咬傷無效
備註： 蝰蛇科（Viperidae）又名蝮蛇科。響尾蛇屬於 蝰蛇科 Viperidae 亞科： 蝮亞科 Crotalinae 屬： 響尾蛇屬 Crotalus
6. 如果受傷15分鐘內，應吸出毒液。
Sawyer Extractor:動物實驗發現，在蛇咬傷三分鐘內使用，可移除大量毒液
7. 禁止當場切開受傷的部位
8.冰敷無法減慢毒液流動，但用毛巾包冰袋可以減輕受傷的疼痛（並沒有禁止冰敷）。不建議浸泡在冰水或將肢體包在冰裡面，會破壞組織(應該是造成類似凍傷)
9. 最好能辨認出是何種毒蛇咬傷，如果有蛇的樣本可參考最好，但死掉的蛇仍然可出現咬合的反射（斷頭的），絕對不要用手去觸碰蛇的頭部
急診治療原則~
要注意心血管以及呼吸系統的維持
最好能辨識出毒蛇種類
在外國,很多蛇咬傷案例是飼主被寵物咬傷,或毒蛇收集者被咬傷,所以通常可以直接知道是哪種蛇類
病史: 被咬傷的時間, 被咬的時候的環境, 咬傷幾處, 被咬的部位, 其他症狀(疼痛 麻木 噁心 嘴巴有金屬的感覺 肌肉痙孿 呼吸困難 頭暈)
是否曾打過破傷風疫苗
過去疾病,平日是否服用藥物
過敏史(是否對馬血清過敏,毒蛇血清幾乎都是用馬去做的)
是否有~氣喘~發燒~蕁麻疹
理學檢查: edema. petechiae. ecchymosis. bullae
compartment syndrome
心血管和呼吸系統檢查
神經學檢查
被咬傷部位的肢體直徑以及靠近心臟五英吋部位肢體的直徑要記錄下來,用來評估毒性反應和抗毒血清治療反應
如果受傷30分鐘內,在急診應該先做急救,包括彈性繃帶纏繞以及吸允毒液(不要用嘴巴吸)
在沒有受傷的肢體打上大號靜脈導管
ECG + CBC + 生化 + 凝血功能 + UA + fibrinogen level + fibrin split products (FDP) + 血型
蛇咬傷常常造成低血壓
使用Doppler檢查末端血液循環,如果發生腔室症候群,應放置壓力監測器以及會診外科(台灣通常是給整形外科)，腔室壓力超過30 mmHg 可能需要筋膜切開術
美國惠氏藥廠對於響尾蛇的咬傷的嚴重度分為五級
grade 0 不用打抗毒血清
grade 1 也不用打血清
grade 2 打 5 vials ~~ IV 1:10 dilution
grade 3 打 5-10 vials~~ IV 1:10 dilution
grade 4 打 10-20 vials~~ IV 1:10 dilution
copperheads咬傷通常會造成水腫,但通常不一定需要打抗毒血清
grade 0 = 沒有中毒的跡象,但懷疑是蛇咬傷,要有fang wound, 輕微疼痛, 小於 1英吋紅腫 edema and erythema, 受傷 12 小時後沒有出現全身性症狀, 抽血檢驗正常
grade 1= 輕微中毒, 懷疑蛇咬傷, 通常有fang wound, 中度疼痛, throbbing localized at the fang wound. 1-5 英吋紅腫. 咬傷後12小時沒有全身性症狀,抽血正常
grade 2= 中度中毒，疼痛程度和範圍更大，朝向軀幹腫脹，瘀血、紫斑侷限在腫脹部位。可能噁心嘔吐及體溫上升。
grade 3= 嚴重中毒，一開始可能表現類似grade １-２，但隨後出現嚴重症狀，腫脹擴散，甚至擴散到軀幹，全身性瘀血及紅疹。可能心跳快、血壓低、體溫異常
grade 4= 非常嚴重中毒，常見於大隻的rattlesnake咬傷，突發性疼痛，腫脹進展快速，數小時內出現軀幹腫脹，ecchymoses, bleb, 壞死.
全身性症狀~噁心嘔吐 頭暈 嘴唇或臉部麻木刺痛(tingling of the lips of face) 肌肉顫動 muscle fasciculations 肌肉疼痛痙孿 painful muscular cramping 蒼白 冒汗皮膚濕冷 脈搏淺快(前面幾個都是休克症狀) 大小便失禁 癲癇 昏迷 可能死亡
給予馬血清之前必須要注意幾件事情
1. 過敏史
2. 每個病患都要做皮膚測試，但陰性反應仍可產生遲發性過敏，測試用的正常馬血清也可能造成過敏，皮膚測試有過敏反應也不是不能打抗毒血清，嚴重中毒者，即使對馬血清過敏還是必須治療。(但 Tintinalli 不建議做血清過敏測試，因為即使過敏還是需要打血清)
皮膚測試: 將血清稀釋一百倍，取0.02mL注射入皮下，陽性反應是指5-30分鐘內出現 WHEAL +/ - 假足PSEUDOPODIA及周圍紅斑 SURROUNDING ERYTHEMA
3. 因為施打馬血清可能造成ANAPHYLAXIS,所以要將急救藥物準備好，打兩條點滴，如果過敏則將注射血清的那一條點滴關閉，使用另一條點滴作急救。如果沒有禁忌症，可在施打血清之前皮下先打0.3mg腎上腺素
4. 體型相對較小的病患，反而需要比例上較多的血清（是相對於體型，不是絕對劑量）。小孩可能比大人需要多一倍以上的抗毒血清（因為小孩的體型比較小，沒有足夠體液去稀釋毒液）
5. 所有抗毒血清都應該靜脈注射給予
6. 懷孕的婦女照樣可以打抗毒血清
7. 不建議在咬傷部位附近施打抗毒血清(p 791) (IgG分子量約 15萬, Fab 分子量約 5 萬, 通常分子量 兩萬以下, 在皮膚注射後的淋巴吸收才會比較理想, 分子量太大無法很好的浸潤)
8. 根據臨床反應決定是否繼續施打血清，如果症狀沒改善，每隔1-2小時重複給予 1-5 VIALS劑量
9. 嚴重中毒的病患即使對血清過敏，仍可施打血清，將血清稀釋，同時也給予腎上腺素
其他：
1. 咬傷30分鐘後，再纏繞繃帶沒有用
2. 咬傷15分鐘內，建議用器材吸出毒液（雖然有文章說，商業用的毒蛇毒液吸出器效果有限）(第八版的書說. 效果不大. 沒有證據顯示有效)
3. 不建議切開蛇咬傷的傷口
4. 建議使用廣效性抗生素(CEFAZOSPORIN)。組織受到嚴重破壞的建議使用PENICILLIN + AMINOGLYCOSIDE
5. 適度止痛
住院病患
1. 抽血驗尿
2. 每隔四小時檢驗: PLATELETS PT/ UA/ MYOGLOBIN/ HEMOGLOBIN
3. 每天詳細的抽血檢驗一次
4. 保持空腹
5. 測量IO
6. 每天換藥檢查傷口, 使用肥皂和水清潔, 覆蓋上無菌敷料
7. 會診外科清創或植皮。通常三天內不清創，直到溶血反應改善。咬傷部位通常不需要外科切開，而且切開通常有害，響尾蛇咬傷常造成大量組織壞死，需要植皮。
8. 血清病: SERUM SICKNESS.
注射超過 10 VIALS 的病患常於一周後發生血清病，治療給予VENA 50mg + CIMETIDINE 300MG Q6H，嚴重個案可給予類固醇。
蛇咬傷只有在出現血清病才需要使用類固醇（唯一的適應症）
9. 其他沒有抗毒血清的毒蛇咬傷可能造成大量肌肉壞死，每天傷口換藥 + 抗生素 + 鹼化尿液(促進MYOGLOBIN排出)
其他參考資料
澳洲官方急救組織對於PRESSURE IMMOBILISATION TECHNIQUE的建議 ２０１１年８月發表
The Pressure Immobilisation Technique (PIT) is recommended for application to bites and stings by the following creatures:
所有澳洲毒蛇 All Australian venomous snakes, including sea snakes [Class A; LOE III]
漏斗網蜘蛛 Funnel Web spider [Class A; LOE IV]
藍環章魚 Blue-ringed octopus [Class B; LOE Expert Consensus Opinion]
芋螺 Cone shell [Class B; LOE Expert Consensus Opinion]
The Pressure Immobilisation Technique is NOT recommended for the first aid management of:
other spider bites including redback;
水母螫傷 jellyfish stings; http://blog.xuite.net/ymmcc/twblog/340600969 http://blog.xuite.net/ymmcc/twblog/341607220
魚螫傷 包括石頭魚咬傷 fish stings including stonefish bites
蠍子、蜈蚣、其他甲蟲螫傷 stings by scorpions, centipedes or beetles.
蜈蚣咬傷 http://blog.xuite.net/ymmcc/twblog/4222 62936
毒蛇的毒液吸出器可能沒有作用 http://www.wretch.cc/blog/ymmcc/817371 http://www.54qiangke.com/shop/product-200.html
