麻醉

Anesthesia, or anaesthesia （see spelling differences;麻醉或麻醉（请参见拼写差异； from Greek αν-, an-, "without";源自希腊文αν-，an-，“无”； and α？σθησι？， aisthēsis, "sensation"）， has traditionally meant the condition of having sensation （including the feeling of pain） blocked or temporarily taken away.传统上，α（σθησι？，“感觉”）是指感觉被阻塞或暂时消失的状态（包括疼痛感）。 This allows patients to undergo surgery and other procedures without the distress and pain they would otherwise experience.这使患者能够进行手术和其他手术，而不会遭受原本会遭受的痛苦和痛苦。 The word was coined by Oliver Wendell Holmes, Sr. in 1846.Another definition is a "reversible lack of awareness", whether this is a total lack of awareness （eg a general anaesthestic） or a lack of awareness of a part of the body such as a spinal anaesthetic or another nerve block would cause.这个词是由奥利弗·温德尔·霍尔姆斯（Oliver Wendell Holmes，Sr.）于XNUMX年创造的。另一个定义是“可逆的缺乏知觉”，无论这是完全缺乏知觉（例如，一般的止痛药）还是对身体部位的缺乏知觉如脊麻或其他神经阻滞会引起。 Anesthesia differs from analgesia in blocking all sensation, not only pain.麻醉与止痛不同，止于止痛。 Anesthesia is pharmacologically induced reversible state of Amnesia,Analgesia,Loss of consciousness, Loss of skeletal muscle reflexes and decreased stress response.麻醉是药理学引起的健忘症，镇痛，意识丧失，骨骼肌反射丧失和应激反应降低的可逆状态。
今天，最广泛形式的全身麻醉一词可以包括：
镇痛：阻止意识的疼痛感;催眠：产生意识丧失;健忘：防止记忆形成;瘫痪：防止不必要的运动或肌肉张力;反射过多，防止过度的自主反射。
Patients undergoing anesthesia usually undergo preoperative evaluation.接受麻醉的患者通常接受术前评估。 It includes gathering history of previous anesthetics, and any other medical problems, physical examination, ordering required blood work and consultations prior to surgery.它包括收集先前麻醉药的历史记录，以及其他任何医疗问题，体格检查，订购所需的血液检查和手术前的咨询。
There are several forms of anesthesia.麻醉有几种形式。 The following forms refer to states achieved by anesthetics working on the brain:以下形式是指通过麻醉药在大脑上达到的状态：
General anesthesia: "Drug-induced loss of consciousness during which patients are not arousable, even by painful stimulation."全身麻醉：“药物引起的意识丧失，即使在疼痛刺激下，患者也无法唤醒。” Patients undergoing general anesthesia can often neither maintain their own airway nor breathe on their own.接受全身麻醉的患者通常无法维持自己的呼吸道，也无法自行呼吸。 While usually administered with inhalational agents, general anesthesia can be achieved with intravenous agents, such as propofol.虽然通常与吸入剂一起使用，但全身麻醉可以通过静脉内剂（如丙泊酚）来实现。
Deep sedation/analgesia: "Drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully following repeated or painful stimulation."深层镇静/镇痛：“药物引起的意识下降，在此期间无法轻易唤醒患者，但在反复或痛苦的刺激下有目的地做出反应。” Patients may sometimes be unable to maintain their airway and breathe on their own.患者有时可能无法维持自己的呼吸道和呼吸。
Moderate sedation/analgesia or conscious sedation: "Drug-induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation."中度镇静/镇痛或有意识的镇静：“药物引起的意识下降，在此过程中，患者有意识地对言语命令做出反应，无论是单独还是伴随轻触觉刺激。” In this state, patients can breathe on their own and need no help maintaining an airway.在这种状态下，患者可以自行呼吸，无需帮助维持呼吸道。
Minimal sedation or anxiolysis: "Drug-induced state during which patients respond normally to verbal commands."最小程度的镇静或抗焦虑作用：“药物诱发的状态，在此状态下患者对口头命令做出正常反应。” Though concentration, memory, and coordination may be impaired, patients need no help breathing or maintaining an airway.尽管注意力，记忆力和协调能力可能受到损害，但患者无需帮助呼吸或保持呼吸道。
The level of anesthesia achieved ranges on a continuum of depth of consciousness from minimal sedation to general anesthesia.从最低程度的镇静到全身麻醉，所达到的麻醉水平取决于意识深度的连续范围。 The depth of consciousness of a patient may change from one minute to the next.患者的意识深度可能会在一分钟到下一分钟之间变化。
以下是麻醉药在脑外起作用所达到的状态：
Regional anesthesia: Loss of pain sensation, with varying degrees of muscle relaxation, in certain regions of the body.区域麻醉：在身体的某些区域，由于不同程度的肌肉松弛而引起的疼痛感丧失。 Administered with local anesthesia to peripheral nerve bundles, such as the brachial plexus in the neck.局部麻醉对周围神经束，如颈部臂丛神经进行麻醉。 Examples include the interscalene block for shoulder surgery, axillary block for wrist surgery, and femoral nerve block for leg surgery.示例包括用于肩部手术的肌间沟阻滞，用于腕部手术的腋窝阻滞和用于腿部手术的股神经阻滞。 While traditionally administered as a single injection, newer techniques involve placement of indwelling catheters for continuous or intermittent administration of local anesthetics.传统上以单次注射方式给药，但较新的技术包括放置留置导管以连续或间歇给药局部麻醉剂。
Spinal anesthesia: also known as subarachnoid block.脊髓麻醉：又称蛛网膜下腔阻滞。 Refers to a Regional block resulting from a small volume of local anesthetics being injected into the spinal canal.指因将少量局部麻醉剂注入椎管而导致的区域性阻滞。 The spinal canal is covered by the dura mater, through which the spinal needle enters.脊柱管被硬脑膜覆盖，脊柱针穿过该硬脊膜进入。 The spinal canal contains cerebrospinal fluid and the spinal cord.椎管内含有脑脊液和脊髓。 The sub arachnoid block is usually injected between the 4th and 5th lumbar vertebrae, because the spinal cord usually stops at the 1st lumbar vertebra, while the canal continues to the sacral vertebrae.蛛网膜下腔阻滞通常是在第4和第XNUMX腰椎之间注射的，因为脊髓通常停在第XNUMX腰椎，而根管则一直延伸到ral椎。 It results in a loss of pain sensation and muscle strength, usually up to the level of the chest （nipple line or XNUMXth thoracic dermatome）。这会导致疼痛感和肌肉力量的丧失，通常达到胸部水平（乳头线或第XNUMX胸皮刀）。
Epidural anesthesia: Regional block resulting from an injection of a large volume of local anesthetic into the epidural space.硬膜外麻醉：将大量局部麻醉剂注入硬膜外腔所致的区域性阻滞。 The epidural space is a potential space that lies underneath the ligamenta flava, and outside the dura mater （outside layer of the spinal canal）。 This is basically an injection around the spinal canal.硬膜外腔是潜在的空间，位于软性韧带下方，在硬脑膜外（椎管外层）之外。这基本上是围绕椎管的注射。
局部麻醉与局部麻醉相似，但会在较小的身体区域发挥作用。