"Dizzy" can describe so many different sensations that the clinician's first priority must be to pin down what each patient means by it. The best way to do this is to ask the patient to describe the feeling(s) without using the word "dizzy." Sometimes it becomes apparent that the patient is, in fact, describing fatigue and weakness, visual difficulty, or anxiety, and such situations must be handled as outlined in Chapters 213, 111, and 202. More often, each subjective sensation of dizziness can be identified more precisely as one of four types of dizziness: vertigo, disequilibrium, presyncope, or lightheadedness. The clinical approach to the dizzy patient depends crucially on distinguishing among these various kinds of dizziness, since the differential diagnosis is peculiar to each type. refers to the illusion of environmental motion, classically described as "spinning" or "whirling." The sense of motion is usually rotatory—"like getting off a merry-go-round"—but it may be more linear—"the ground tilts up and down, like being on a boat at sea." Disorientation in space and some sense of illusory motion are the common denominators here. Vertigo always reflects dysfunction at some level of the vestibular system, and these problems are discussed in Chapter 123. represents a disturbance in balance or coordination such that confident ambulation is impaired. Symptomatically, some such patients clearly profess that "the problem is in my legs," but others feel "dizzy in the head, too." Common to all patients with disequilibrium is the perception that ambulation either causes the problem or clearly makes it worse. Observation of the patient's gait and a careful neurologic examination are thus essential in evaluating this type of dizziness. means that the patient senses loss of consciousness. When the patient has, in fact, experienced true syncope (actual loss of consciousness), considerations in Chapter 12 apply. When the patient has not ever actually lost consciousness, the complaint "I feel like I will pass out" should be viewed skeptically, since other types of dizziness may be so described. In such circumstances, the approach to syncope in Chapter 12 may or may not be pertinent. is very difficult to describe without using the word "dizzy," but this verbal imprecision is, in fact, very helpful to the clinician. Lightheadedness refers to a sensation "in the head" that is clearly not vertiginous or presyncopal, and that is invariably related to ambulation. This vague "negative definition" emphasizes that the lightheaded patient's description is always hazily imprecise, and even articulate patients are frustrated by the request to describe the feeling without saying "dizzy." Some describe "floating" or feeling "like my head is not attached to my body," being "high," or "giddy." Many will search for a better description but finally concede, "I just feel dizzy, that's all."
“头晕”可以描述许多不同的感觉，因此临床医生的首要任务必须是明确每位患者所说的“头晕”具体指什么。最好的方法是让患者在不使用“头晕”这个词的情况下描述这种感觉。有时会发现患者实际上描述的是疲劳、虚弱、视觉障碍或焦虑，这种情况必须按照第213章、第111章和第202章所述进行处理。更常见的情况是，每种主观的头晕感觉可以更精确地确定为四种头晕类型之一：眩晕、平衡失调、晕厥前状态或头重脚轻感。对头晕患者的临床处理方法关键取决于区分这些不同类型的头晕，因为每种类型的鉴别诊断都有所不同。眩晕是指环境运动的错觉，经典描述为“旋转”或“打转”。运动感通常是旋转性的——“就像从旋转木马上下来”——但也可能更呈线性——“地面上下倾斜，就像在海上乘船”。空间定向障碍和某种虚幻的运动感是这里的共同特征。眩晕总是反映前庭系统某个层面的功能障碍，这些问题将在第123章中讨论。平衡失调是指平衡或协调受到干扰，导致自信行走受损。从症状上来说，一些这类患者明确表示“问题出在我的腿上”，但另一些人也感觉“头部也头晕”。所有平衡失调患者的共同之处在于，他们感觉行走要么会引发问题，要么会明显使问题加重。因此，观察患者的步态并进行仔细的神经系统检查对于评估这类头晕至关重要。晕厥前状态是指患者感觉即将失去意识。当患者实际上经历了真正的晕厥（实际失去意识）时，适用第12章中的考虑因素。当患者实际上从未失去意识时，对于“我感觉自己要晕倒了”这种主诉应持怀疑态度，因为其他类型的头晕也可能如此描述。在这种情况下，第12章中关于晕厥的处理方法可能相关，也可能不相关。头重脚轻感如果不使用“头晕”这个词很难描述，但这种语言上的不精确实际上对临床医生很有帮助。头重脚轻感是指一种“头部”的感觉，显然不是眩晕或晕厥前状态，并且总是与行走有关。这种模糊的“否定定义”强调，头重脚轻的患者的描述总是模糊不清，即使表达能力强的患者在被要求在不使用“头晕”的情况下描述这种感觉时也会感到沮丧。有些人描述为“飘浮”或感觉“好像我的头和身体不相连”、“飘飘然”或“头晕目眩”。许多人会试图寻找更好的描述，但最终会承认，“我只是感觉头晕，仅此而已”。
