Definition"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. Show
Vertigo 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. Disequilibrium 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. (Pre)syncope means that the patient senses impending 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. Lightheadedness 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 not 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." TechniqueHistoryThe patient's initial spontaneous description is usually the best clue to the type of dizziness. Do not ask leading questions until the patient has attempted to elaborate in his or her own words on "dizzy." As the patient describes symptoms, the clinician must try to interpret those descriptions so as to formulate an initial hypothesis: Which of the four types of dizziness does this sound like? When dizziness is episodic or recurrent, ask the patient to recount in detail the setting, circumstances, and events of the most recent or most memorable occurrence(s). Following the patient's untutored tale, analyze the symptoms as you would analyze any symptom: How often does this occur? How long does it last? What seems to you to bring it on? What makes it worse? What makes it better? Is the problem improving or worsening? Are there other symptoms associated with the dizziness? Often, at the conclusion of the patient's history, a tentative hypothesis has been reached about the type of dizziness, and sometimes even about the specific diagnosis (see below). Table 212.1 illustrates the causes of dizziness among 104 patients studied in a dizziness clinic. Of note is the fact that the most common specific causes of the four general types of dizziness will often be recognizable simply by listening to the patient for a few minutes. For example: Among patients with vertigo, benign positional vertigo is most common. This condition usually afflicts middle-aged and older persons who describe brief episodes of vertigo that are always and only positional, that is, vertigo (and sometimes nausea or vomiting) occurs episodically when the patient moves his or her head into a particular position, as when turning over in bed, looking up, or moving from a standing to supine position. Unlike patients with many other types of vertigo, patients with benign positional vertigo are asymptomatic except when changing position. Such a description must be analyzed as outlined in Chapter 123, but the history alone often makes the diagnosis. Similarly, the most common cause of lightheadedness is hyperventilation, a diagnosis that must be confirmed by testing (see below) but that is usually strongly suspected after analyzing the patient's history. Hyperventilators may initially describe "loss of balance" or "unsteadiness" or "feeling like I will faint," but, in fact, closer questioning usually reveals that this dizziness is very vague, unpredictable, often constantly present but intermittently worse, and inconsistently related to position, activity, or ambulation. Frequently hyperventilators describe associated symptoms that emanate from multiple different organ systems—episodic palpitations, abdominal bloating, paresthesias, and weakness are especially common. This concatenation of seemingly disparate symptoms associated with very vaguely described dizziness is typical of hyperventilation. In fact, the patient often punctuates the conversation with an occasional deep-sighing respiration of which he or she may be unaware but which is obvious to the alert interviewer. Multiple sensory deficit syndrome is the most common cause of disequilibrium, and, again, the history alone usually shouts out the diagnosis. These patients are often elderly people afflicted by a variety of ills that summate to impair the patient's ability to ambulate unassisted. Visual impairment, deafness, peripheral neuropathy, painful or disabling orthopedic disorders, and muscle weakness collectively conspire to alter the patient's perception of space, fluidity of motion, and confidence in walking. These people usually complain simply "I am unsteady on my feet" or "I am afraid I will fall" and are dramatically improved by the use of a cane or the supporting arm of a companion. A thorough examination and observation of the patient's gait are essential here, but the history always points the way. Finally, orthostatic hypotension is probably the most common cause of presyncope (these disorders in general are greatly underrepresented in Drachman and Hart's study-group in Table 212.1). Such patients feel as if they will faint (not just fall), and this occurs episodically only in the upright position and is invariably alleviated quickly by lying down. The patient often will not have realized the purely "orthostatic" nature of the dizziness, but listening to the patient's description of typical episodes always reveals that crucial connection. When such "classic" clinical histories are not forthcoming, and especially when the general type of dizziness remains unclear, the clinician can prompt the patient with a variety of analogies of the different types of dizziness. Describing to the patient examples of "dizziness types" often allows the patient to describe vague feelings more clearly. For example, brief vertigo has been experienced by many people after spinning on a revolving stool or chair, in amusement parks, or after overindulging in alcohol. Disequilibrium can be likened to the sensation of walking in complete darkness, especially if drowsy, as may occur when awakening in the night to go to the bathroom. Presyncope is familiar to people who have felt brief orthostatic faintness upon standing up after a prolonged squat, as when gardening or working on the floor. A surprising number of people have, in fact, fainted at some time in the past and can readily identify with the sense of impending faint. Finally, while lightheadedness is difficult to describe, it is almost universally understood in an intuitive, if not experiential, sense. Many lightheaded patients who directly deny the above analogies will immediately brighten when the word is suggested—"Yes, that's it exactly; I feel lightheaded!"—despite the irony that the hallmark of lightheadedness is its inexactitude. Physical ExaminationWhile the history is almost always more revealing than the physical examination of dizzy patients, the examination is important for two reasons. First, when the history clearly suggests one specific type of dizziness, the physical examination is directed at specific pertinent organ systems. The patient with vertigo must undergo careful neurologic and otologic examination, and the clinical assessment of spontaneous and/or positional nystagmus is essential (see Chapter 128). The patient with presyncope requires careful cardiac and hemodynamic evaluation (see Chapter 12). Disequilibrium demands a thorough general and neurologic examination with specific emphasis on ocular, auditory, and proprioceptive function. The lightheaded patient, so often anxious or depressed, will not and should not be satisfied unless thorough physical assessment excludes the occasional "organic" cause—anemia, thyroid disease, or recurrent cardiac arrhythmias. Second, the physical examination of the dizzy patient should always include the performance of several dizziness simulation tests. Drachman and Hart demonstrated the usefulness of these tests when they achieved specific diagnoses in 95 of their 104 patients listed in Table 212.1. Any practicing clinician will admire that rate of success. While Drachman and Hart utilized a sophisticated battery of neuro-otologic tests, a few simple "bedside" maneuvers often suffice, as enumerated in Table 212.2. The patient's blood pressure and pulse should be taken sequentially in the supine, sitting, and standing positions. Orthostatic hypotension is the most common cause of presyncope, and reproduction of the patient's symptoms associated with a fall in blood pressure upon assuming the upright position establishes that diagnosis. Sometimes the fall in blood pressure is delayed, and the patient's blood pressure and pulse should be taken again after a few minutes" standing and/or a brief walk. Intravascular volume depletion and certain drugs are the most common causes of orthostatic hypotension, and usually the pulse rises as the blood pressure falls in such patients. When disease of the autonomic nervous system is the cause, the pulse may not rise when the blood pressure drops. The patient's gait and Romberg testing should be observed. Disequilibrium disorders are often diagnosed on the basis of these observations (see Chapters 67, 68, and below). Vestibular function should be tested by examining the patient's extraocular movements for nystagmus and by performing the Nylen-Bárány maneuvers for positional nystagmus and vertigo (see Chapter 127). Finally, the patient should perform voluntary hyperventilation. Here the patient is placed in the supine position and is asked to breathe deeply and rapidly (about 30 times per minute) through the mouth for as long as 3 minutes continuously. The patient should not be told what to expect. Many normal individuals will develop mild lightheadedness during hyperventilation, and this maneuver is thus useful because it "simulates" lightheadedness—the patient with vertigo, disequilibrium, or presyncope will say, "No, that is not what I feel." Many lightheaded patients, however, are chronic hyperventilators who will very rapidly (within 30 seconds) develop "their symptoms" and experience distress—panic, fluttering eyelids, awkward "thoracic" breathing patterns will emerge, and the patient will spontaneously announce, "That's it! That's my dizziness!" Such a self-realization is an important event among lightheaded patients (see below). These dizziness simulation tests help in several ways:
At the conclusion of the history and examination, the great majority of dizzy patients can be confidently assigned to one of the four categories outlined in Figure 212.1. Further differential diagnosis and treatment then depend on the specific type of dizziness involved. Additional discussion of the approach to vestibular disease and (pre)syncope can be found in Chapters 123 and 127 respectively. A few further points about patients with disequilibrium and lightheadedness are discussed below. Figure 212.1Differentiation among the four types of dizziness. Basic ScienceSee Syncope (Chapter 12), Motor System and Gait (Chapter 68), Autonomic Nervous System (Section V), and Vertigo (Chapters 123 and 127) for discussion of the mechanisms of dizziness. Clinical SignificanceDisequilibriumAs noted previously, a detailed general and neurologic examination are essential to the diagnosis of disequilibrium because the syndrome of multiple sensory deficits is so often the cause. The other keys to diagnosis of disequilibrium are:
Begin the analysis of gait with the Romberg test. The patient stands upright, feet together, with the arms at the sides. The patient able to maintain balance in this position is asked to close his or her eyes. Loss of equilibrium only with the eyes closed usually suggests disordered proprioceptive and/or vestibular function, while an abnormal Romberg response with the eyes open or closed is usually cerebellar in origin. Next, watch the patient walk away from you, turn, and return. The gait of the patient with multiple sensory deficits is usually merely hesitant and apprehensive, and minimal assistance from a cane or companion renders the gait fluid and confident. This type of gait in a patient with two or more major sensory deficits is usually diagnostic. A similar type of gait is seen in some very elderly people who do not have multiple sensory deficits. This "senile gait" is not associated with senility (dementia), but that unfortunate label remains popular. Such patients" gait, when unassisted, is "scared" and slow; when minimally assisted, it may be brisk and assured. If the examiner is not observant, he may miss the patient with early parkinsonism or frontal lobe apraxia. Early in the course of parkinsonism—before the appearance of the classic tremor and "cogwheel" rigidity—disequilibrium and difficulty walking are common findings. At this stage the gait is slow, arm swing is diminished, and turning is disproportionately clumsy. At more advanced stages the parkinsonian gait is "festinating": steps are short and tight, the feet shuffle along, the trunk is bent forward, the arms hang motionless at the sides. Some have likened this appearance to that of the lower body shuffling frantically forward to "catch up" with the rest of the body. Frontal lobe apraxia may be only subtly different in its gait, but thorough neurologic examination usually reveals evidence of dementia and other "frontal lobe" signs in such patients. This gait has been likened to "walking on ice": from a standing position, the patient has difficulty initiating the walk. Steps shuffle to "get going" as if the patient knows how to walk but does not know how to begin. A gentle nudge at the elbow often is the greatest help to these people. Turning is especially instructive as the apraxic patient may appear stuck to the-floor, often pivoting around one stationary foot as if one-legged. Cerebellar ataxia and severe peripheral neuropathy are always easy to recognize. The ataxic patient is not a bit subtle—the patient usually reels unsteadily with short, irregular steps, feet held wide apart as if straddling an invisible barrier, often lurching from side to side or falling, especially when attempting to stop, sit, or turn around. The Romberg test will be abnormal with eyes open or shut. Peripheral neuropathy is only rarely severe enough itself to cause disequilibrium, but it is a common component of the multiple sensory deficit syndrome, especially in alcoholics or diabetics. The hallmark of the neuropathic gait is that the patient "must see to walk," since proprioceptive function has deserted him. The patient often walks bent forward, watching his feet interact with the ground. This sight can be superficially comical: the legs are usually held apart, each foot is flung out and forward, often higher than necessary, and stomped to the ground as if the patient were wearing frogman's flippers. This gait has been likened to that of a circus clown wearing oversized shoes. Thus, patients with specific structural neurologic disorders will suffer from "predictable" disequilibrium, that is, their gait will always be abnormal when tested. The patient with multiple sensory deficits, parkinsonism, apraxia, or ataxia may have good and bad days, but the gait will never be normal. In contrast, some patients describe disequilibrium that is episodic and unpredictable; examination of such patients" gait may be unremarkable when the patient is asymptomatic. Common causes of such episodic disequilibrium are various vestibular disorders, transient cerebrovascular insufficiency, metabolic disorders, hyperventilation, and psychogenic disequilibrium. Some patients with vestibular disease will neither describe nor admit to vertigo. This is especially true of "central" vestibular disease (see Chapter 123)—acoustic nerve neoplasms, multiple sclerosis, drug (alcohol, anticonvulsants, tranquilizers) toxicity, tumors of the brain stem or cerebellum. But the much more common peripheral vestibular disorders may also cause only a nonspecific sense of disequilibrium, especially in the elderly. Careful neurologic examination is always the clue to the central disorder; the history of disequilibrium induced by positional head changes will usually suggest the atypical presentation of a peripheral disorder. Transient attacks of cerebrovascular ischemia may cause dizziness, and the risk of subsequent catastrophic stroke in such patients always makes the clinician worry about this diagnosis in the elderly or hypertensive patient with episodic disequilibrium. Fisher's classic studies of transient ischemic attacks can help allay or heighten our worry if we remember several of his conclusions:
"Metabolic" disorders should be remembered in the patient with disequilibrium. Always ask about all prescription and nonprescription drugs used by the patient. Many people fail to make the connection between the onset of disequilibrium and the use of new (or higher doses of) medication. Hypothyroidism may cause dizziness, ranging from mild episodic disequilibrium to frank ataxia. Episodic hypoglycemia is a fashionable (and usually incorrect) diagnosis among neurotic dizzy patients, but vague dizziness that is always temporally postprandial should raise this legitimate question. Severe anemia may cause vague disequilibrium, as may hyponatremia, adrenal insufficiency, or any cause of hypotension. Hyperventilation is an extremely common cause of intermittent disequilibrium, even though "lightheadedness" is the usual complaint of hyperventilators. This reminder reemphasizes two important caveats about the patient with disequilibrium or, in fact, any dizzy patient:
LightheadednessThere are four general scenarios that pertain to the patient whose dizziness "sounds" lightheaded:
Finally, when you remain confused about the dizzy or lightheaded patient, when nothing "fits," when the examination and dizziness simulation tests are unrevealing, ask a few innocent personal questions: "How's life? Are you happy? Are you under pressure at home or work? Is your family well? Is your marriage good? Do you feel frightened often? Are you depressed? Do you get panicky for no good reason?" Such seemingly ingenuous questions will often "open Pandora's box" in the patient whose dizziness is but one somatic manifestation of either deep personal distress or frank psychiatric illness. If we look at and listen to the whole person, the examiner need not feel faint just because the patient feels dizzy. Most dizzy patients can be helped, and the clinical process leading to that end can be a provocative and satisfying experience. References
Which body function can be inferred from observing the balance and coordination status of a child quizlet?Which body function can be inferred from observing the balance and coordination status of a child? The cerebellum controls balance and coordinated body movements. By assessing the child's balancing and coordination of body movements, the nurse can elicit the function of the cerebellum.
Which actions by the nurse are helpful in conducting an effective interview with a child and the parents quizlet?Which actions by the nurse are helpful in conducting an effective interview with a child and the parents? The nurse: introduces self first and then asks the name of each family member, including the child. informs the family about the limits of how much health information is kept confidential.
Which assessment finding would the nurse expect when assessing a preschooler's chest quizlet?When assessing a preschooler's chest, the nurse would expect: movement of the chest wall to be symmetric bilaterally and coordinated with breathing.
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