昏迷和格拉斯哥昏迷量表

Coma发生在脑does not have enough nutrients.

Coma is a state of decreased consciousness whereby a病人无法与周围环境做出反应环境ment。Outside physical or auditory stimulation does not waken the person. Patients may have different levels of decreased consciousness and responsiveness depending upon how much or how little of the brain is functioning. PatientsinAComa do not voluntarily interact with their environment.

无法唤醒昏迷与睡觉。

这格拉斯哥昏迷量表was developed to provide healthcare professionals with a simple way of measuring the depth of coma based on observations ofeye-opening, speech, and movement. Patients in the deepest level of coma:

• 不要以任何身体运动对pain，，，，
• do not have any speech, and
• do not open their eyes.

那些昏迷的人可能会对口头或痛苦的刺激提供一些回应，以至于它们似乎醒了，但符合昏迷的标准，因为他们没有通过启动来对自己的环境做出反应voluntary动作。

格拉斯哥昏迷量表被用作对患者初步评估的一部分，但无助于对昏迷原因进行诊断。由于它“得分”了昏迷水平，因此，格拉斯哥昏迷量表可以用作任何医疗保健专业人员的标准方法EMT，，，，paramedic,nurse，，，，or神经外科医生，，，，to assess change in the patient's mental status over time.

这best use of the Glasgow Coma Scale is to allow healthcare professionals of differentClinical技能和培训以始终长时间评估患者，以确定患者是否正在改善，恶化或保持不变。按时间顺序，在最初的护理中，可能会有急救人员，紧急医疗技术人员（EMTS），护理人员，护士，急诊医师，神经科医生和神经外科医生，在不同时间在不同时间内评估同一患者。格拉斯哥昏迷量表允许可以共享的标准评估。

• 完全清醒的患者的格拉斯哥昏迷得分为15。
• A person who is dead has a Glasgow Coma Scale of 3 (there is no lower score).

Coma occurs when the brain does not have enough nutrients. For example, if inadequate amounts ofoxygenor血糖（（葡萄糖）将其传递给它，大脑可以“关闭”。Trauma，，，，bleeding, orswelling of the brain能影响血delivery, various poisons can also directlyinjurethe brain, and braininflammationAnd infection can also alter mental status and lead to coma.

To understand unconsciousness, it is important to understand why a person is awake. The brain is a large器官有很多部分。大脑有两个“侧面”，左右Cerebral hemispheres。这y each contain额叶，，，，parietal，，，，temporal，，，，Andoccipital移动的裂片，sensation，言语和思想经过处理。这小脑sits beneath theCerebral半球和对照bAlanceAnd coordination. The脑stem工艺自动，无意识Controls of the body includingheartrate,血pressure，，，，And呼吸。网状激活系统（RAS）位于脑干内，是意识和睡觉。

• To be awake, the reticular activating system (RAS) must be functioning, as well as at least one cerebral hemisphere.
• 如果Aperson loses consciousness, either the RAS has stopped working, or both cerebral hemispheres have shut down.

这reticular activating system stops working in two situations:

1. 脑干中风：Cells in that area of the brain stem have lost their blood supply and the oxygen, and glucose that it delivers. This shuts off the reticular activating system. Thisevent要么是缺血性（血液供应丢失），要么hemorrhagic（（bleeding occurs and damages the reticular activating system).
2. A pre-death event:increased swelling in the brain pushes down on the brain stem and causes it to fail.

为了使两个脑半球一次失败，整个大脑的功能都必须丧失。这可能是由于缺乏血流，例如，当心脏的节奏扰动（例如心室fibrillationCAuses the heart to stop beating. Severely decreased levels of oxygen in the blood due to lung failure can cause脑损伤。Poisoning或大脑的炎症会导致昏迷，而两个脑半球的功能丧失。Trauma是昏迷的另一个潜在原因。

次要的头部受伤能CAuse brief意识丧失，，，，but the brain is able to turn itself back on. Similarly, patients withseizuresbecome unconscious - but waken relatively quickly as the brain recovers from theseizure的“电风暴”。那些有重大创伤或长期创伤的人seizuresmay not wake quickly and may remain in coma for a longer period of time.

这skull是一个保护大脑的刚性盒子。不幸的是，如果大脑受伤并开始肿胀（edema), there is no space to accommodate additional fluid. As a result, increased pressure within the brain compresses the braintissue靠在头骨骨头上，可能导致意识水平降低。如果是颅内压力继续增加而没有治疗，肿胀会将大脑向下推向脑干所在的颅骨底部的开口。这场危机会导致大脑疝，并关闭网状激活系统。这会影响大脑刺激的能力呼吸AndControl血pressure，，，，leading to死亡。

这effect of trauma on the brain is not predictable. Relatively minor force to the skull and brain can be catastrophic. There does not have to be obviousinjury可视化Computerized tomography（（CTscan) imaging of the brain to cause significant damage. In fact, when shear injury occurs, thescanmay be normal, even if the patient is in coma. Shear injury ismicroscopicinjury to individual神经Connections within the brain without obvious swelling or bleeding.

Head trauma can cause different types of脑injury。脑组织本身可能发生损伤，或者可能导致大脑和头骨之间的空间出血，或者在ventricles深的within the brain tissue.计算机断层扫描（（CT) of the head may be able to identify most bleeding from trauma.

大脑内流血（脑内hemorrhage) may be small, but also may cause associated swelling that may cause damage to the brain and result in coma. Blood is in the brain tissue is irritating and leads to inflammation with swelling. Many patients with small amounts of bleeding have the potential to recover very well.

Picture of the brain and potential brain injury areas

大脑的衬里有多层，这些层可以充当可能发生出血的潜在空间。

硬膜外血肿Are located between the skull and the tissue that covers the brain (dura mater）。这se hematomas that are localized collections of loose blood are often associated with skullfracturesAnd tears in arteries located near thefracturesite.

Subdural hematomasAre located beneath thedura当从颅骨到大脑的桥接静脉被撕裂时，会发生。

As the blood continues to accumulate, pressure builds within the skull and the brain is shifted away from the site of bleeding, compressing the brain against the skull. With both hemispheres of the brain compromised,意识丧失And coma may result. The more swelling, the higher the intracranial pressure, the deeper the coma.

Each brain is different and in older patients whose brains have atrophied and become smaller with age, there is more room in the skull to accommodate a small amount of swelling or bleeding. Each bleeding situation is different and each patient is assessed individually. However, being unconscious because of brain bleeding and/or swelling is associated with a poorer outcome than unconsciousness from drugtoxicity，，，，orseizures，，，，etc.

Subarachnoid hemorrhage（在蛛网膜层下方出血）发生在脑衬里的层中脑脊液（（CSF） 位于。CSF是在大脑深处的心室中产生的，是沐浴大脑和的营养液脊髓。出血这里可能会引起一些症状或cAuse significant problems like coma or中风。Bleeding is often associated with a significant头痛And脖子刚性。

出血可能会在头骨或大脑中出现而不会出现创伤。这种出血形式的一些医学原因包括：

• Hypertension（（高血压): when blood pressure is too high, and not controlled, blood vessels in the brain may not be able to tolerate the high pressure and may leak blood into the brain,subarachnoid空间，或两者兼而有之。
• Cerebral动脉瘤，或血液中的区域vesselthat is congenitally weak and ruptures. Some people are born with blood vessels that have a weak wall that can gradually balloon, like a weak spot in an innertube。在他们生命中的某个时间，或者也许从来没有，弱点让位，血液洒到了蛛网膜下腔中。
• 动静脉畸形（AVM）为Abnormal动脉直接连接到静脉的血管并引起潜在的较弱的斑点，可能会渗出血液。通常，动脉分为越来越小的容器，直到形成最小的船只毛细血管。Capillaries form meshes where chemicals, nutrients, oxygen, andCArbon dioxide从血液交换为单个细胞。然后，毛细血管合并以形成较大的血管，即静脉。在AVM中，这种关系动脉to毛细管to the静脉is abnormal and is at risk for bleeding.
• 肿瘤，，，，eitherbenignor恶性，，，，能be veryvascular（（Composed of many arteries, veins, and capillaries) and have significant bleeding potential.

Just as blood takes up space within the skull and can cause coma, so may脑tumors。Brain tumors may be associated with localized swellingedema，，，，inflammation, and bleeding.

• 癫痫发作，，，，中风- 症状，降低心理状态和行为改变可能是最初的symptom。
• Most often, the symptoms have a gradual发作，，，，but coma can progress quickly if bleeding or swelling occurs.

While trauma can make the brain swell, other types of injury or insult can cause脑swelling（（Cerebral edema）。侮辱是缺氧还是异常电解质，它最终可能导致脑组织的水肿。与出血一样，头骨限制了可用于大脑肿胀的空间。结果，脑组织被损坏，其功能降低，其压缩越多，颅骨的骨骼就越被压缩。

感染And inflammation, such as脑炎Andmeningitis大脑和周围组织的昏迷可能与昏迷有关。

• Encephalitis is an infection of the brain tissue itself, whilemeningitisis an infection of the linings surrounding the brain.
• 感染s may also be associated with abscesses or collections ofpuswithin the brain.
• 感染s may alter brain function and cause coma even without any swelling that might be detected on aCTscan。

这脑requires oxygen to function, and without it, the brain shuts down. There is a very short time to return oxygen supply back to brain tissue before there is permanent damage. Most research suggests that the time window is only four to six minutes.

这body provides oxygen to the brain through thelungs。这lungsextract oxygen from the air,hemoglobininred blood cellspick up the oxygen, and the heart pumps blood through normal blood vessels to cells in the brain and the休息of the body. If any part of the system fails, the oxygen supply to the brain can be interrupted.

这most common failure occurs with heart rhythm disturbances. The coordinated electrical beat of the heart is lost and theheart muscledoesn't squeeze blood adequately; no blood is pumped to the brain and it stops functioning almost immediately.

肺也会失败，导致hypoxemia;examples include肺炎，，，，气肿，，，，orAsthma。In each case, inflammation in the lungtubes（（支气管or支气管oles) or lung tissue makes it difficult for oxygen to get into the lungs and transferred into the bloodstream.血红蛋白Also takes carbon dioxide, the waste product ofmetabolism，，，，And returns it to the lungs to be exhaled. Elevated levels of carbon dioxide in the blood also can affect brain function to cause coma.

贫血，，，，orlow red blood cell count，可能导致大脑直接失效，或者更有可能导致其他器官像心脏失败。内心，就像其他任何人muscle，，，，requires oxygen to function. Anemia can occur chronically or it can be due to an急性血loss (examples include trauma or bleeding from the胃）。如果失血缓慢，人体可以更好地适应和耐受低血红蛋白水平；如果出血迅速发生，人体可能无法补偿，其结果是对包括大脑在内的组织的氧气不足。

All cells in the body need glucose and oxygen to perform their functions byAerobic（征用氧气）metabolism。尽管没有这两种营养素（厌氧），身体的其他部位可以持续很短的时间，但大脑却不能。没有葡萄糖，大脑功能几乎立即停止。

Hypoglycemia（（low blood sugar) most often occurs in people with糖尿病who have given themselves too muchinsulinor have not taken in enough食物。

In normalphysiology， 这pancreas产生胰岛素并平衡其产生的量与血液中的葡萄糖量。有人糖尿病need to inject insulin into their bodies or takemedicationto stimulate the pancreas to make insulin. If too much insulin is injected, glucose levels in the bloodstream decrease, and not enough glucose is delivered for the brain cells to function. While tight control of血葡萄糖水平对于防止长期并发症很重要糖尿病，，，，including心脏病，，，，周边血管疾病，，，，blindness，，，，Andkidney failure;还需要密切监视以防止hypoglycemic昏迷。

People who do not have糖尿病还可能有低血糖由于不需要胰腺异常分泌过多的胰岛素，因此不需要胰岛素。

有两个来源的毒药,会影响the brain, those that we take into the body (through ingestion or inhaling), and those that the body generates and cannot dispose of in some way.

如果是body can be considered a factory, it needs to have the ability to get rid of the waste products that are made when the body generates energy. These waste products can cause different organs in the body to fail, including the brain.

这liverperforms many functions including glucose andproteinmanufacturing. It also breaks down and metabolizes chemicals in the body. When theliver失败，不同的化学物质Ammonia可以积累并可能对大脑有毒Cell功能。Hepaticencephalopathy或肝昏迷时发生肝脏因急性或Chronicinjury. The most common cause isCirrhosis由于慢性滥用酒精。

这kidneys filter blood to rid the body of waste products. When the kidneys fail, a variety of waste products can accumulate in the bloodstream and cause direct or indirect damage to the brain. Direct causes includeuremia，，，，where blood尿素levels rise and are directly toxic to brain cells. Common causes ofkidney failure包括控制不善糖尿病or poorly controlled高血压。

这thyroidACts as the恒温器为了the body, producingthyroid hormoneto regulate thespeed身体发挥作用。如果thyroid激素水平在一段时间内逐渐下降太低粘液水肿昏迷可能会因为深刻而发生hypothyroidism。

Ingestions can cause the brain to slow down, speed up, or alter its perception of the world. Some ingestions may cause coma in an indirect way.Acetaminophen过量的效果延迟。它直接对肝脏有毒，但需要几天liver failure发生，导致肝昏迷和死亡潜力。

Alcoholis probably the most common cause of ingestedpoisonortoxin，，，，leading to altered mental status and coma. In acute alcohol intoxication, the brain is directly poisoned. Blood alcohol levels fall when the alcohol is metabolized by the liver, but the depth of intoxication can be so great it shuts off many of the非自愿控制呼吸并保持肌肉功能的大脑活动。阿片类似painpills orheroinAnd other sedatives like sleeping pills can cause similar slowing of brain function to the point that the person stops breathing.

CocaineAnd amphetamines are the common "uppers" or brain stimulants. These brain stimulants cause anAdrenaline- 类似身体反应，导致血压升高和心率，增加的风险心脏病发作，心律障碍或大脑出血。

When a patient presents in a coma, diagnosis, and treatment begin simultaneously. Initial treatment is aimed at addressing immediate life-threatening issues:

• ABC完好无损吗？是病人的Airway open? Are theybreathing? Do they have goodC不足（心跳和血压）？
• 是病人hypoglycemic？血液糖能be checked quickly by a quick fingerstick bedside test and if it is low, glucose can be administered in themouth或静脉注射。患者糖尿病Also may have a胰高血糖素injection kit at home that can be administered to rescue them from糖尿病昏迷。
• Did the patient ingest a麻醉？Naloxone（（纳尔坎) may be given intravenously to reverse an overdose situation.

History remains an important key to the diagnosis. Since the patient cannot be the source of information, questions are asked offamily，，，，friends, bystanders, and rescue personnel. For example, imagine a person sitting at a bar who falls down, hits他的head, and is in a coma. While it might be easy to jump to the conclusion that he was intoxicated, fell, and bled in his brain, other scenarios need to be considered. Did he have a心脏病发作，他遭受了中风，或者这可能是导致的糖尿病药物反应low blood sugar？

Once the patient has been stabilized with acceptablevitalsigns, a more complete physical examination will likely include a complete neurologic assessment. Examination of the eyes including the pupils and the interior of the eye where blood vessels and nerves enter the globe (fundi), facial movements to assess颅神经including gag反射，，，，extremity对刺激的运动和反应，肌腱反射es, and another testing of spinal绳索功能。这re is special注意力付给对称性的神经病学exam, since lack of movement or response on one side of the body may be caused by bleeding inside the skull or by中风。

Pupilsize and response to light are commonly assessed. If a pupil is widely dilated, it is either because of direct trauma to the eye or more ominously, it is a pre-death event where the brain is herniating because of increased intracranial pressure. Unequal pupil size (Anisocoria）通常是10％的人口中的正常变异。完全清醒的患者中的扩张的学生通常不是sign大脑内压力的升高。

一般考试调查skin为了Cuts，，，，scrapes，伤口等。如果怀疑创伤，脖子可能会被固定，因为头部受伤通常有相关的颈部骨折。

这格拉斯哥昏迷量表score will be documented; the deeper the coma, the lower the score. Please appreciate that a person with a "normal" Glasgow Coma Scale of 15 may still have altered mental status. Repeated neurologic assessment is key to monitoring the status of the patient and determining if the coma is improving, worsening, or remaining stable.

这tests required to evaluate a coma will depend upon the suspected cause. Many times, the cause involves many factors and the sequence of events will require serious detective work. Blood tests,心电图AndCTscanof the head are most often obtained. Further test options depend upon the patient's situation.

Depending upon the diagnosis, the evaluation may be no more than assessing blood糖，，，，treatinghypoglycemia，，，，And having complete解决of the situation. On the other hand, the cause of coma may be a catastrophic脑出血without hope for significant recovery. The outlook very much depends on the cause of the coma and the ability to treat the particular situation.