Goroll_Primary Care Medicine, 8e

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SECTION XIV Ear, Nose, and Throat Problems

Frequency (Hz)

Frequency (Hz)

Hearing Loss (dB)

Hearing Loss (dB)

FIGURE 212-3 Normal pure-tone air audiogram. DISCRIM, discrimina tion; O, right ear, air; × , left ear, air; R, right; L, left.

FIGURE 212-4 Air–bone gap. DISCRIM, discrimination ; O, right ear, air; < , right ear, bone; R, right.

of the pure-tone thresholds. Discrimination testing evaluates speech understanding using standardized word lists. Speech discrimination that is diminished out of proportion to the mea sured hearing loss is suggestive of cochlear nerve pathology. Ordinarily, patients with good pure-tone thresholds should also understand speech well. Tympanometry measures the compli ance of the tympanic membrane and is often conducted with audiometry. A flattened tympanogram suggests middle ear fluid, and other patterns may help to identify ossicular discontinuity and other conductive hearing loss problems. ANNOTATED BIBLIOGRAPHY 1. Paul BC, Roland T Jr. An abnormal audiogram. JAMA 2015;313:85. ( A case-based exercise for generalist clinicians in audiogram interpretation. )

measures both conductive and sensorineural hearing. To appre ciate a conductive component to a hearing loss, bone conduc tion thresholds are obtained. The bone conduction audiogram bypasses the conduction system and measures cochlear/cochlear nerve capacity. In bone conduction testing, the mastoid process of each ear is directly stimulated with an oscillator or vibrator over a similar frequency spectrum, and results are graphically recorded. A discrepancy between air conduction thresholds and those for bone-conducted sounds, the so-called air–bone gap, is indicative of a conductive hearing loss (Fig. 212-4). Additional testing includes SRT and speech discrimination testing . The SRT is defined as the lowest intensity at which the patient can correctly identify 50% of presented words. The SRT should match, within a few decibels, the average

Chapter 213

APPROACH TO EPISTAXIS NEIL BHATTACHARYYA M ost spontaneous nosebleeds are self-limited. Patients present for medical care when the bleeding becomes unusually brisk or will not stop or episodes become frequent. In addition, bleeding that drains posteriorly into the oropharynx rather than anteriorly is especially daunting for patients. Severe or recurrent bleeding necessitates evaluation for nasal pathol ogy and, less commonly, an underlying generalized disorder. The immediate therapeutic objective is control of the bleeding.

Trauma In patients with deviated septum or septal spurs in the ante rior portion of the nose, trauma occurs easily, either from the drying effects of poorly humidified air or secondary to probing in or bumps on the nose. Nose picking, nose rubbing, or forceful nose blowing may also trigger bleeding when the nasal mucosa is inflamed and fragile from a viral, bacterial, or allergic cause.

PATHOPHYSIOLOGY AND CLINICAL PRESENTATION (1–6) Etiologies Ulcerations Ulcerations, which tend to form over septal deviations and spurs, bleed easily. Repeated mucosal exposure to cocaine leads to anoxic tissue necrosis from drug-induced intense vasospasm; perforation may result from cocaine use and cause chronic crusting and bleeding. Collagen diseases such as lupus are occasionally responsible for ulceration. The prolonged use of the widely prescribed topical nasal steroid sprays may lead to Copyright © 2020 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. The primary mechanisms of epistaxis involve disruption of the nasal mucosa, most commonly caused by trauma , ulceration , bleeding disorders , and inflammatory or neoplastic conditions .