氯胺酮
Ketamine
Ketamine Hydrochloride
別名: Ketaset · Ketaflo · Ketalar · Ketaject · VetaKet · Anaestamine · Anesketin · Ketavet · Narketan-10 · Vetalar-V · CI-581 · CL-369 · CN-52372-2 · ketamini hydrochloridum · Ketamine hydrochloride
由 VetSheet 獸醫團隊審訂更新於 2026年4月5日本內容以實證獸醫文獻為本
經審核的 v13 劑量證據
結構化劑量計算證據Ketamine/benzodiazepine combinations — Postoperative analgesia
須由已驗證獸醫確認
NA
必須同時考慮的臨床上下文 (4)
- 1. Ketamine is used in many different combinations with other agents. The following are representative, but not necessarily inclusive; it is suggested to refer to a recent veterinary anesthesia reference for more information. 31,32
- 2. Do not confuse IV CRI dosages listed as mg/kg/HOUR with those listed as µg/kg/MINUTE.
- a) Ketamine/benzodiazepine combinations:
- Ketamine injection should be stored between 15°C to 30°C (59°F-86°F) and protected from light. The discard dates after first vial puncture vary by manufacturer; refer to the specific product label for further information.
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
概覽
氯胺酮 (Ketamine) 是一種在獸醫學中廣泛使用的速效、解離性全身麻醉劑和鎮痛劑。
- 藥物類別：屬於苯環利定 (PCP) 衍生物。
- 臨床效果：誘導僵直狀態，特徵為深度的軀體鎮痛、失憶，以及大腦丘腦皮質系統與邊緣系統的解離。與傳統麻醉劑不同，它不會誘導第三期麻醉。
- 反射保留：病患通常會保留腦神經反射，包括咽、喉、角膜和踏步反射。眼睛通常保持睜開。
- 心血管系統：通常會刺激心血管系統（增加心率、血壓和心輸出量），這是由於交感神經張力增加所致，使其適用於血流動力學不穩定的病患（但禁忌用於肥厚型心肌病）。
臨床要點：由於單獨使用氯胺酮會導致肌肉僵直且缺乏內臟鎮痛效果，因此幾乎總是與肌肉鬆弛劑（例如咪達唑侖或地西泮等苯二氮平類藥物）或 α-2 激動劑（例如右美托咪定、甲苯噻嗪）合併使用，以確保平穩誘導、充分的肌肉鬆弛和更平穩的甦醒。
作用機制
Ketamine exerts its effects through multiple central nervous system pathways:
- NMDA Receptor Antagonism: Acts as a non-competitive antagonist at the N-methyl-D-aspartate (NMDA) receptor → binds to the PCP site inside the calcium channel pore → prevents glutamate-mediated calcium influx → blocks central sensitization and prevents the "wind-up" phenomenon associated with chronic or severe pain.
- Neurotransmitter Modulation: Inhibits GABA and blocks the reuptake of serotonin, norepinephrine, and dopamine in the CNS.
- CNS Dissociation: Depresses the thalamoneocortical system (responsible for sensory perception) while simultaneously activating the limbic system (involved in memory and emotion).
- Sympathetic Stimulation: Increases sympathetic tone by promoting norepinephrine release → leads to increased heart rate, cardiac output, and blood pressure. Note: Ketamine has direct negative inotropic effects on the myocardium, which are usually masked by this sympathetic surge unless the patient is catecholamine-depleted.
安全性與警告
禁忌症
- Prior hypersensitivity reactions to ketamine
- Animals intended for human consumption
- Use as a sole agent for major surgery (due to poor muscle relaxation and visceral analgesia)
- Increased cerebrospinal fluid (CSF) pressure or head trauma
- Significant hypertension, heart failure, or arterial aneurysms
- Hypertrophic cardiomyopathy (HCM) in cats
- Increased intra-ocular pressure or open globe injuries (relative)
- Procedures involving the pharynx, larynx, or trachea (relative)
- Preexisting seizure disorders (use with extreme caution)
- Animals whose eyes are at risk of perforation
- Raised intraocular pressure (IOP)
- Raised intracranial pressure (ICP)
不良反應
- Hypertension
- Hypersalivation
- Respiratory depression (at high doses or rapid IV administration)
- Hyperthermia (especially in cats)
- Emesis
- Vocalization
- Erratic and prolonged recovery (emergence delirium)
- Dyspnea
- Spastic jerking movements and muscular tremors
- Seizures (up to 20% of cats at therapeutic doses)
- Hypertonicity and opisthotonos
- Cardiac arrest
- Pain after IM injection
- Eyes remain open (risk of corneal drying/ulceration)
- Cardiovascular depression and arrhythmias (in animals with high sympathetic tone, shock, or severe CV disease)
- Tachycardia (following high IV doses)
- Marked respiratory depression (in some animals)
- Skeletal muscle hypertonicity and spontaneous movement (if used alone)
- Spacey, abnormal behaviour or dysphoria during recovery (1-2 hours)
- Drug accumulation and prolonged recovery (with prolonged infusion)
注意事項
Cardiovascular Caution: Ketamine increases heart rate, blood pressure, and myocardial oxygen consumption. Avoid in patients where this is detrimental (e.g., unstable shock, congestive heart failure, hypertrophic cardiomyopathy).
Ocular Care: Cats' eyes remain open after receiving ketamine. Protect from injury and apply an ophthalmic lubricant (e.g., Lacri-Lube) to prevent excessive corneal drying.
- Hepatic/Renal Insufficiency: Use with caution. In cats, ketamine is excreted almost exclusively via the kidneys; reduce doses or use cautiously in feline renal disease.
- Sympathetic Tone: Use with caution in animals with preexisting increased sympathetic tone (e.g., pheochromocytoma, hyperthyroidism).
- Recovery: Minimize exposure to handling or loud noises during the recovery period to reduce the incidence of emergence reactions (delirium, thrashing), but continue to monitor vital signs closely.
- Hemorrhage: Because ketamine can increase blood pressure, careful control of post-surgical hemorrhage (e.g., declawing) is required.
藥物相互作用
May prolong the anesthetic actions of ketamine
May prolong the recovery time after ketamine anesthesia
Recovery rates may be prolonged and the cardiac stimulatory effects of ketamine may be inhibited; close monitoring of cardiac status is recommended
Recommended not to use ivermectin in reptiles within 10 days of ketamine
May cause enhanced or prolonged respiratory depression
May induce severe hypertension and tachycardia; beta-blockers may be of benefit in treating these effects
Synergistic anaesthesia and prevention of muscle hypertonicity. Reversal of the alpha-2 agonist must be delayed until 45 minutes after ketamine administration to prevent unopposed ketamine excitation.
Synergistic anaesthesia and prevention of ketamine-induced skeletal muscle hypertonicity.
監測
- Level of anesthesia and analgesia
- Respiratory function
- Cardiovascular status (heart rate, rhythm, blood pressure)
- Eyes (monitor to prevent drying or injury)
- Body temperature (monitor for hyperthermia or hypothermia)
- Heart rate and rhythm
- Respiratory rate and depth
- Depth of anaesthesia
- Corneal lubrication status
- Quality of recovery (monitor for dysphoria)
藥物動力學
半衰期
吸收
After IM injection in the cat, peak levels occur in approximately 10 minutes. Sublingual spray in cats is absorbed enough to have pharmacologic action.
分佈
Distributed into all body tissues rapidly, with highest levels found in the brain, liver, lung, and fat. Plasma protein binding is approximately 50% in the horse, 53% in dogs, and 37-53% in cats.
代謝
In most species, metabolized in the liver principally by demethylation and hydroxylation. One active metabolite, nor-ketamine, has 10-30% of the activity of the parent compound. In cats, ketamine is almost exclusively excreted unchanged.
排除
Eliminated primarily in the urine. Redistribution out of the CNS is more of a factor in determining duration of anesthesia than is the elimination half-life.
過量
Ketamine has a wide therapeutic index (approximately 5 times greater than pentobarbital).
- Signs of Toxicity: When given too rapidly or in excessive doses, significant respiratory depression may occur.
- Treatment: Treatment using mechanically assisted respiratory support is recommended over the use of analeptic agents. In cats, yohimbine combined with 4-aminopyridine has been suggested for use as a partial antagonist.
可用產品
劑型
- Injection: 10 mg/mL
- Injection: 50 mg/mL
- Injection: 100 mg/mL
- Injectable: 100 mg/ml solution
獸醫用
- Ketamine HCl for Injection: 100 mg/mL in 10 mL vials (Ketaject, Ketaset, Keta-sthetic, Vetalar, VetaKet)
- Anaestamine 100 mg/ml injection
- Anesketin 100 mg/ml injection
- Ketaset 100 mg/ml injection
- Ketavet 100 mg/ml injection
- Narketan-10 100 mg/ml injection
- Vetalar-V 100 mg/ml injection
人用標示
- Ketamine HCl Injection: 10 mg/mL in 20 mL vials
- Ketamine HCl Injection: 50 mg/mL in 10 mL vials
- Ketamine HCl Injection: 100 mg/mL in 5 mL vials (Ketalar)
各地核准狀態
POM-V CD SCHEDULE 2
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Store between 15-30°C (59-86°F) and protect from light. Solution may darken upon prolonged exposure to light, which does not affect potency. Do not use if precipitates appear. Do not mix with barbiturates or diazepam in the same syringe or IV bag as precipitation may occur.
飼主須知
重要提示：氯胺酮是一種管制藥物，僅由獸醫專業人員在臨床環境中給藥。
- 眼睛護理：您的寵物在藥物作用期間眼睛可能會保持睜開。獸醫團隊會塗抹保護性眼藥膏以防止眼睛乾燥和受傷。
- 甦醒期：在寵物甦醒期間，請將其安置在安靜、昏暗的環境中。盡量減少噪音、突然的動作和過度撫摸，以防止藥效消退時出現驚嚇反應、不規則動作或幻覺。
- 注意事項：觀察是否有任何異常的抽搐、長時間的昏沉或異常行為，並及時向您的獸醫報告。
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用，不能取代專業判斷或廠方最新藥品說明書。