Analysis of this will allow correct assessment of: 24-hr urine volume \200 Number and severity of incontinence episodes \200 Maximum and m inimum voided volume \200 Diurnal variation Table 20.1 Bladder diary Date Time Voided volume Symptoms Incontinence episodes and cause 536 CHAPTER 20 Incontinence Urinary incontinence: management \200 Depends on cause so try to make a diagnosis \201 rst. \200 Incontinence is multifactorial in most elderly so combining treatments may be n ecessary eg a man with obstructive prostatic symptoms and detrusor hyperactivity may bene \201 t from an A -blocker and an anti- muscarinic (eg tolterodine) (Table 20.2 ). Table 20.2 Management of urinary incontinence Treatment Indication Notes Overactive bladder syndrome/detrusor over activity Bladder retraining (gradually increasing time between voiding) Dementia Decreases likelihood of incontinence episodes Regular toileting (taking to toilet every 2 \200\2234hr) Overactive bladder syndrome Pelvic \202 oor exercises Stress incontinence Effect wears off when exercises stop May precipitate urinary retention \200\224 monitor carefully Bladder stabilizing drugs Overactive bladder syndrome/detrusor overactivity Tolterodine 2mg bd \200\2234mg od Side effects of dry mouth, constipation, postural hypotension may limit effectiveness. Solifenacin 5 \200\22310mg od Trospium chloride 20mg bd Titrate dose up slowly. Use for 6 weeks before maximal effect. Oxybutynin 2.5mg bd \200\2235mg tds Refer for urodynamics to prior to surgery Surgery For stress incontinence \200\224 tension-free vaginal tape (TVT) is promising new procedur e \200\224 female Colposuspension \200\224 gold standard operation \200\224 male For out \202 ow tract obstruction TURP Slow onset of action Anti-androgens For prostatic hyperplasia Improves \202 ow and obstructive symptoms Decreased libido/impotence Finasteride 5mg od A -blockers Doxazosin 1mg \200\2234mg od Tamsulosin 400micrograms od Titrate dose slowly \200\224 watch for hypotension (especially postural) and syncope/falls Smooth muscle relaxant for BPH \200\224 improves \202 ow and obstructive symptoms Useful for co-treatment of hypertension URINARY INCONTINENCE: MANAGEMENT 537 Table 20.2 (Contd.) Treatment Indication Notes Sometimes helps reduce large residual volumes and decrease UTI Double micturition (ask patient to repeat voiding) Surprisingly well tolerated in \200\230 \202 exible \200\231 elderly Intermittent catheterization Atonic/hypotonic bladder \200\224 removing residual volumes daily can aid continence and r educe renal damage and infection. Also used to dilate stenotic urethras Useful for nocturnal frequency Main troublesome side effect is dilutional hyponatraemia \200\224 unlicensed for > 65s in the UK Synthetic vasopressin either oral or intranasal Caution in patients with comorbid conditions, likely to be exacerbated 538 CHAPTER 20 Incontinence Catheters A catheter is indicated for: \200 Symptomatic urinary retention \200 Obstruct ed out \202 ow associated with deteriorating renal function or hydronephrosis Acute renal failure for accurate urine output monitoring \200 Intensive care settings \200 Sacral pressure sores with incontinence \200 Where other methods of bladder managem ent cause undue distress to a frail older person Occasionally to facilitate discharge home by reducing care needs (especially overnight) whe re non-catheter options have failed 2 A catheter is NOT usually indicated for: \200 Immobility \200\224 even from stroke \200 Heart failure \200\224 just because you are giving furosemide \200 Monitoring \202 uid balance in a continent patient \200 Convenience of nursing \200\224 at home or in hospital \200 Asymptomatic chronic retention \200\224 refer to urology for assessment Catheter selection \200 Long-term catheters should be either silicone, Silastic, or silve r- impregnated (expensive but reportedly fewer blockages and infections) Catheter size should be as small as practical \200 Catheters should be changed at least e very 3 months \200 Consider the use of a catheter valve (like a beer keg tap) rather than a drainage bag If duration is likely to be more than a year, consider suprapubic placement to preserve urethral sphincter function CATHETERS 539 HOW TO Manage urinary incontinence without a catheter In spite of correct diagnosis, investigation and treatment of reversible causes there will still be patients who will be permanently or intermit- tently incontinent of urine. 2 An in dwelling catheter is not always the best solution. They have been shown to increase morbidi ty (infection, stones, urethral erosion) and even mortality. Suggesting that catheters are removed is one of a geriatrician \200\231s most important job s in post-acute care. If in doubt involve a specialist continence nurse/team. Other options for continence management include: Environmental modi \201 cations : urinals/commodes by the bed, easy access clothing, etc. can minimize or prevent accidents Regular or individualized toileting programs : this can be very successful in patients with dementia but is labor intensive Pad and pants : can be very effective but is quite labor intensive for very immobile patients A drainage sheath or condom catheter (Conveen is a manufacturer) for men: like a cathete r but held onto the penis with a plastic sheath like a condom. Particularly useful for isol ated nocturnal incontinence as it can be removed by day. Main problem is displacement and l eakage which can be a problem with small or unusually shaped penises Intermittent catheterization : for those with obstruction or atonic bladders. Consider in a gile, cognitively intact patients. Can be supported by district nursing services 540 CHAPTER 20 Incontinence HOW TO Treat catheter complications Blocked catheters \200 Consider possibility of stones, infection, sediment, encrustation, constipation or bladder tumor Renew catheter and change if necessary \200 Maintain good \202 uid intake \200 Cathet er maintenance solution can be used for short periods \200 Blockage due to sediment can b e prevented with regular saline bladder washouts Catheter encrustation occurs with Proteus infection; acidic irrigations instilled into the bladder may dissolve these (eg Suby G ) \200\230Bypassing \200\231 \200 Catheters can irritate bladder causing contractions \200\224 resulting leak of urine past catheter can render them useless and occasionally cau ses very painful spasms This is particularly common where detrusor overactivity was cause of incontinence Can be induced or aggravated by infection \200 Exclude catheter blockage (presents with i dentical spasms and leaks) \200 If no residual volume, reduce catheter diameter/balloon s ize \200 Antimuscarinic drugs can sometimes help \200 Longer-term catheters can cause u rethral sphincter incompetence, so urine will leak continuously. This may be temporarily he lped by passing a larger gauge catheter but is a dif \201 cult problem to manage \200\224 avoid by using suprapubic catheters earlier Catheter infections \200 All catheters become colonized after a few days, all catheter ur ine will dipstick positive, and most catheter specimens of urine will grow bacteria 2This alone is not an indication for antibiotics \200 Bad smelling, dark colored, and clo udy urine is more commonly due to dehydration and is not an indication for antibiotics per se There are now some trials of cranberry juice/capsules that suggest there is a minor effect on reducing recurrent infections Only treat clinically signi \201 cant infections (fever, malaise, delirium, pain, abnormal in \202 ammatory markers, etc.) or you will just promote resistant organism s If you believe a catheter is a source of signi \201 cant infection: Send a catheter specimen of urine to guide antibiotic choice \200 Remove the catheter whe re possible (even if only for 48hr). If not possible change catheter with a single shot of im gentamicin 80 \200\223120mg Ensure adequate hydration \200 Choose a narrow spectrum antibiotic if sensitivities allow \200 For repeated signi \201 cant infection consider if the catheter is really necessary. Low-dose continuous antibiotic prophylaxis are advocated by some but there is li ttle evidence This page intentionally left blank 542 CHAPTER 20 Incontinence Fecal incontinence: causes De \201 ned as the involuntary passage of feces in inappropriat e circum- stances. The importance of situational factors mean there is potential for anyone to be incontinent in some circumstances. \200 Incontinence of feces is always abnormal, and often curable \200 It is much less common than urinary incontinence, but more distres sing \200 There is gross under-referral for diagnosis and treatment \200 Prevalence \200\224 10 % of care home residents incontinent at least once per week Continence mechanisms \200 The sigmo-rectal \200\230sphincter \200\231 \200\224 the rec tum is usually empty. Passage of feces into the rectum initiates rectal contraction (and anal relaxation), normally temporar ily inhibited. The acute angle in the pelvic loop of the sigmoid may be important in causin g temporary holdup The ano-rectal angle \200\224 the pubo-rectalis sling maintains an acute angle between rec tum and anus, preventing passage of stool into the anal canal The anal sphincters \200\224 the external sphincter (striated, voluntary muscle), the inte rnal sphincter (smooth muscle), and the anal vascular cushions which complete the seal Ano-rectal sensation \200\224 sensation in the anus and rectum is usually suf \201 cientl y accurate to distinguish gas from feces, permitting the passage of \202 atus without inc ontinence. Good sensation may be particularly important when diarrhea is present Causes of fecal incontinence \200 Disorders of the anal sphincter and lower rectum: sphin cter laxity (from many causes), severe hemorrhoids, rectal prolapse, tumors, constipation Any cause of fecal urgency (occasionally associated with reduced mobility): constipation (w ith spurious diarrhea), any cause of diarrhea (in \202 ammatory bowel disease, drugs, etc. ) Disorders of the neurological control of the ano-rectal muscle and sphincter: LMN lesions (neuropathic incontinence), spinal cord lesions, cognitive impairmen t (neurogenic incontinence) The commonest cause ( > 50 % ) is fecal impaction. This is important because 95 % are curab le. The second commonest cause is neurogenic incontinence where the cure rate is still arou nd 75 % . fecal INCONTINENCE: ASSESSMENT 543 Fecal incontinence: assessment Most patients can be helped by asking a few questions and pe rforming a rectal examination. Effective treatment is directed at the underlying cause so adequate assessment is vital. History \200 The duration of symptoms is not helpful: impaction is just as common in thos e who have been incontinent for more than 3 months as in those in whom the incontinence is recent Having the bowels open regularly (eg every day) is usual in elderly patients with impaction Complete constipation (not having the bowels open at all) is unusual in impaction A feeling of rectal fullness with constant seepage of semi-liquid feces is almost diagnosti c of impaction, but rectal carcinoma may also present in this way The combination of urinary and fecal incontinence strongly suggests impaction as the cause of both Soiling without the patient being aware of it suggests neuropathy Examination \200 Inspect the anus \200\224 and ask the patient to strain as if at stool. Look for in \202 ammation, deformities, large hemorrhoids (internal or external), and pro lapse Rectal examination \200\224 assess anal tone by the pressure on the \201 nger after asking the patient \200\230tighten \200\231, feel for feces and tumor, it is easy to miss even large internal hemorrhoids unless proctoscopy is performed Abdominal examination \200\224 feel for the descending colon. Work proximally to assess colonic fecal loading (this may be misleading) \200 Neurological exa mination \200\224 look for signs of a peripheral neuropathy, and other neurological damage . Check perianal sensation (sacral dermatomes). Include a mental status assessment if you t hink neurogenic incontinence is likely Investigation A plain abdominal radiograph may be necessary to detect proximal fecal loadin g of the colon (see b \200\230Fecal incontinence: management \200\231, p.544). Investigati on of the anal sphincter tone and neurological control of rectum and anus is in the provinc e of the proctologist and may occasionally be needed for neuropathic incontinence. 544 CHAPTER 20 Incontinence Fecal incontinence: management The two common treatments in old age are for constipation an d neuro- genic incontinence. In addition specialist proctology clinics can perform ano-rect al physiology assessment prior to the use of biofeedback tech- niques and surgery (even col ostomy). Treatment of constipation Fecal impaction, fecal retention, fecal loading. 2In hospitalized older people, constipation is by far the commonest cause of incontinence; assume that any incontinent patient is constipated until proved otherwise and do not exclude it until after an adequate thera- peutic trial of enemas for high fecal impaction. See b \200\230Constipation \200\231, p.370 for de \201 nition, diagnosis, causes, prevent ion, and treatment of constipation, and b \200\230HOW TO treat \200\234over \202 o w \200\235 fecal incontinence \200\231, p.545. Mechanism Passage of feces from the sigmoid into the rectum (often soon after a meal \200 \224 the gastro-colic re \202 ex) produces a sensation of rectal fullness, and a desire to defecate. If this is ignored, the sensation gradually habituates, and the rectum \201 ll s up with progressively harder feces. At this stage, some leakage past the anal sphincter ( incontinence) is almost inevitable. Impaction of hard fecal material produces partial obstr uction, stasis, irritation of the mucosa with excessive mucus production, and spurious diar rhea. Emptying the colon of feces has two main effects: it prevents spurious diarrhea and t herefore urgency and it permits normal colonic motility and habit to be restored. Treatment of neurogenic fecal incontinence Loss of control of the intrinsic rectal contract ion caused by passage of normal fecal material from the sigmoid into the rectum results in the involuntary passage of a normal, formed stool at infrequent intervals, and usually at a timing characteristic of that patient (typically after breakfast). It is a syndrome analogous with the uninhibited neurogenic bladder, and usually only occurs in the context of severe dementia. However, note that incontinence in demented patients is commonly due to constipation. The diagnosis is therefore usually made in a severely dement ed patient with a characteristic history after excluding the other common causes. Since the diagnosis is usually one of exclusion, it is reasonable to treat most patients as though they have impaction, particularly if you cannot exclude high impaction by radiology . Once impaction has been excluded, there are three strategies: \200 In patients with a r egular habit, toileting at the appropriate time (perhaps with the aid of a suppository) may be successful. This requires an attendant who k nows the patient well Arrange for a planned evacuation to suit the carers, by administering a constipating agent (eg loperamide 2mg od) combined with a phosphate enema two or three times weekly If the patient has no regular habit and refuses enemas, the situation may have to be accepted and suitable protective clothing provided fecal INCONTINENCE: MANAGEMENT 545 HOW TO Treat \200\230over \202 ow \200\231 fecal incontinence \200 General \200 \224 rehydration (possibly iv), regular meals, and help with toileting are important Enemas \200\224 eg phosphate enema given once or (occasionally) twice daily. Continue unti l there is no result, the rectum is found to be empty on DRE and the colon is impalpable ab dominally. This may take a week or more Complete colonic washout \200\224 eg using bowel prep such as Picolax . This is rather an extreme method but is sometimes required. Ensure the patient is well hydrated before you start Manual evacuation of feces \200\224 can cause further damage to the anal sphincters and is almost never necessary Laxatives \200\224 generally less effective than enemas but can be used in addition, for milder cases and in the very frail. If the stool is hard use a stool softenin g laxative such as lactulose (20mL/day) \200\224 stimulant laxatives (eg senna) may produc e severe pain. Stimulant laxatives or suppositories may be appropriate for those with soft fecal overloading. A combination of stool softener and stimulant are sometimes used. While extra \201 bre is useful in prophylaxis, stool bulking agents such as methylcellulose are of limited value in treating constipation as they increase the volume of stool being passe d and may increase your problems 2After treatment, think prevention (see b \200\230Constipation \200\231, p.370). If, despite these measures, a patient has impaction for a second time (without an obvious a nd removable cause) then regular (say once or twice weekly) enemas should be prescribed. Pr ogress can only be satisfactorily monitored by examining the patient abdominally and rectal ly. This page intentionally left blank 547 Chapter 21 Ears Deafness and the ageing ear 548 HOW TO Communicate with a deaf person 549 HOW TO Assess hearing 550 Audiology 551 Hearing aids 552 HOW TO Use a hearing aid 554 Tinnitus 556 Vertigo 558 Vertigo: assessment 560 HOW TO Examine the vestibular system 561 Vertigo: management 562 HOW TO Perform Epley \200\231s maneuver 562 548 CHAPTER 21 Ears Deafness and the ageing ear Deafness is a common, debilitating complaint that increases wit h age. 6 % of adults, 33 % of retired people and 80 % of octogenarians in the UK have impai red hearing. Deafness is often ignored ( \200\230part of getting older \200\231) yet it pre vents communication, causes social isolation, anxiety, depression, and can contribute to fu nctional decline. Around half of sufferers could be helped by a hearing aid, yet less than a fourth have one. Generally patients with unilateral, mild bilateral, or profound bilateral deafness do not bene \201 t from conventional hearing aids. 2Be alert to hearing loss. A quick assessment directs appropriate referral to audiology or ENT when necessary. Normal ageing Presbyacusis \200 Describes the decline in hearing that commonly occurs wit h age \200\224 \200\230degenerative deafness \200\231 Males > females \200 Usually detectable from age 60 \200\22365 \200 Both the sensory pe ripheral (cochlea) and central (neural) components of the auditory system are affected with peripheral degeneration being accountable for at least 2/3 of the clinical features of pre sbyacusis \200 A variety of possible mechanisms exist \200\224 cellular degeneration giv es rise to a reduction in the numbers of hair cells particularly at the basal end of the co chlea (the part responsible for high frequency sound appreciation). Circulatory changes suc h as atherosclerosis, microangiopathy, and atrophy of the stria vascularis contribute The relative contributions of \200\230normal ageing \200\231 and cumulative exposure to no xious stimuli (noise, toxins, oxidative stresses, otological disease, poor diet, vascular d isease) are unclear, but not all older people have hearing problems The high frequencies are lost \201 rst \200\224 usually noticed when high-pitched female voices become hard to hear. As consonants are high frequency, the patient can often hear n oise, but not understand, feeling that everyone is \200\230mumbling \200\231 (loss of disc rimination) \200\230Recruitment \200\231 is a common problem, where the thresholds for hearing and discomfort are very close ( \200\230Speak up don \200\231t shout \200\231) Busy, noisy environments make hearing harder, so patients may avoid social situations There is no treatment to halt progression, but hearing aids may help Other ear changes with age These include: \200 Thinner walls to the external auditory canal, with fewer glands, making it dry and itchy Drier wax due to decreased sweat gland activity, making accumulation (a cause of reversible hearing impairment) more common \200 Degenerative changes of the i nner ear and vestibular system contributing to increase in deafness, vertigo, and tinnitus DEAFNESS AND THE AGEING EAR 549 Classifying deafness Conductive A disturbance in the mechanical attenuation of sound waves in outer/ middle ear, preventing sound from reaching the inner ear. \200 It can be caused by outer ear obstruction (eg wax, foreign body, otitis externa), some types of tympanic me mbrane perforation, tympanosclerosis, or middle ear problems (effusion, otosclerosis, ossic ular erosion secondary to infection or cholesteatoma) It may be surgically correctable, and can be helped by a hearing aid Sensorineural A proble m with the cochlea or auditory nerve so impulses are not trans- mitted to the auditory cort ex. \200 Caused by genetic or perinatal factors in children \200 In adults may be traum atic, infective (viral, chronic otitis media, meningitis, syphilis), noise induced, degener ative (presbyacusis), ototoxic (eg aminoglycosides, cytotoxics), neoplastic (acoustic neuro ma) or others such as M ni re \200\231s disease Usually irreversible \200 The appropriate hearing aid can be helpful \200 Cochlear impl ants can be considered in severe sensorineural deafness, but seem less effective than in younger patients, perhaps due to limitations in cerebral pr ocessing Mixed A combination of both conductive and sensorineural \200\224 probably the most common cause in older people. HOW TO Communicate with a deaf person \200 Ensure hearing aids are inserted correct ly, turned on and have working batteries Speak clearly and at a normal rate \200 Use sentences, not one word answers \200\224 thi s gives contextual cues to lip readers Increase volume, but do not shout \200 Lower the pitch of the voice \200 Minimize backg round noise \200 Maximize face-to-face visual contact \200\224 look straight at the pers on, and ensure there are not bright lights behind you that will dazzle Use visual cues when talking (eg hand gestures) \200 Be patient \200\224 repeat things i f asked, changing the sentence slightly if possible If confusion arises, write things down \200\224 do not give up 550 CHAPTER 21 Ears HOW TO Assess hearing General Conversation will give an informal idea of hearing abil ity. Clarify by performing free \201 eld speech tests by asking the patient to repeat words sp oken in a whispered voice, conversation voice and shouted at 60cm from the ear. The non-tes t ear is masked by pressing the tragus backwards and rotating it with the index \201 nger . Sit the patient next to you so that lip reading is not possible. History \200 Rate of onset and progression (witnesses will often be more accurate than patients) Unilateral or bilateral \200 History of trauma, noise exposure or ear surgery \200 Fami ly history of hearing problems or hearing aid use \200 History of ototoxic drugs, eg amin oglycoside antibiotics (gentamicin, streptomycin, etc.) and high-dose furosemide Associated symptoms (pain, discharge, tinnitus, vertigo) Examination \200 External ear an d canal (looking for wax, in \202 ammation, discharge, blood, abnormal growths, etc.) Drum (perforations, myringitis, retraction, bulging of drum, etc.) \200 Tuning fork tests (with a 512kHz fork) may be helpful. Both are based on the principle of improved bone conduction perception with a conductive hearing los s \200 Rinne \200\231s \200\224 compares air and bone conduction. Hold tuning fork in fr ont of ear then place on mastoid, to compare air and bone conduction. Air > bone is normal. Bone > air implies defective middle and outer ear function Weber \200\231s \200\224 assesses bone conduction only. Hold tuning fork at vertex of the head and ask which ear hears the sound most loudly. With conductive deafness, it is heard loudest in the deafer ear; with sensorineural deafness it is heard most loudly in the normal ear Who to refer? Patients with sinister features should be referred to an ENT surgeon: \200 Recent or abrupt hearing loss \200 Unilateral hearing loss or tinnitus \200 Variable he aring loss \200 Ear pain 2Sudden onset sensorineural deafness is an ENT emergency, and re quires urgent referral (causes include infection, vascular event, tumor, leaking canals, et c.) ALL other patients with suspected hearing loss should be referred routinely to an audiologist for further assessment and management. AUDIOLOGY 551 Audiology The majority of patients with hearing impairment are managed by audiolo- gists an d hearing therapists. They do the following. Specialized hearing tests \200 Audiometry \200\224 quanti \201 es the degree and patter n of loss. May be \200\230pure tone \200\231 (using signals at varying frequencies and int ensities) or \200\230speech \200\231 (discriminating spoken words at differing intensities ). The hearing thresholds are charted on an audiogram and interpreted by the audiologist (i ndicates conduction or sensorineural deafness, which frequency and which ear) Impedance tympanometry \200\224 indirectly measures the compliance of the middle ear, iden tifying infection and effusion in the middle ear and eustachian tube dysfunction Evoked response audiometry \200\224 measures action potentials produced by sound. No consc ious response is required by the patient and so tests are less open to bias. (Before MRI, t his was the main diagnostic test for acoustic neuromas) Recommend and \201 t hearing aids Many types. Help patients to have realistic expectation s about their hearing aids (rarely a \200\230miracle cure \200\231) and train them how to use them opti- mally (eg minimizing background noise). Program digital hearing aids. Offer practical advice About assistive listening devices such as: \200 Alternative signal s \200\224 buzzers and \202 ashing lights instead of doorbell or telephone ring; vibrati ng devices that attach to the wrist and alert the wearer to environmental noises. Hearing d ogs can also be used Television \200\224 subtitles, or devices that connect to the hearing aid allowing the television signal to be ampli \201 ed Telephones \200\224 with high/low volume control and \200\230T \200\231 settings that amp lify the telephone noise without the background noise Transmitter and receiver devices (infrared or FM radio wave) for use in theaters, etc. with transmission from the sound source. The listener can adjust the volume in their receiver Advise about better communication Run aural rehabilitation programs \200\224 age-matched g roup sessions that help with adjustment to the sudden reintroduction of noise with a hearin g aid (after what is usually a gradual hearing loss), teach skills (eg blocking out backgro und noise, lip reading) and share practical tips (eg eating in a booth at a restaurant to l imit background noise). Other \200 Train people to lip read \200 Help manage tinnitus \200 Counsel about psyc hosocial implications of hearing impairment 552 CHAPTER 21 Ears Hearing aids The past decade has seen many advances in hearing aid technology and performan ce. Modern hearing aids offer improved \201 delity, greater ampli- \201 cation, and fre quency-speci \201 c ampli \201 cation. Patients who have tried hearing aids in the past a nd not found them bene \201 cial should be encour- aged to try them again. What do hearing aids do? Generally consist of a microphone that gathers sound, an ampli \201 er that increases the volume and a receiver that transmits ampli \201 ed sound. Most hearing aids also include circuitry that \201 lters and processes sound prior to ampli \201 cation. Whom do they help? \200 Help many to some degree, but not all \200 Does not restore nor mal hearing \200\224 the wearer needs to learn to interpret the new auditory input ef \201 ciently Conductive hearing loss is helped more than sensorineural loss What are the different types? Different sizes \200 Smaller units (eg completely-in-the-ca nal devices) are cosmetically more appealing and give good reception for mild \200\224 moderate hearing loss, but are \201 ddly and expensive Medium-sized units (eg in-the-ear devices) are more visible, and have more feedback, but can be used for worse hearing loss Larger units (eg behind-the-ear) provide the most ampli \201 cation and are easier to hand le, but suffer from feedback if the ear mold deforms Monaural versus binaural \200\224 binaural hearing aids yield a subjective improve- ment i n sound clarity, but monaural may be considered for unilateral loss. Analog devices \200 Cheapest, with least processing of sound \200 Set to hearing loss a t the time of \201 tting \200 Audiologist adjusts ampli \201 cation and tonality setti ngs at time of \201 tting, but these are then \201 xed Patient can adjust the volume manually (turn the device volume up when the noise is quiet, and down when it is loud) Digitally programmable devices \200 More expensive, with moderate sound processing \200 Analog circuit that can be adjusted at the time of \201 tting by a computer program to best \201 t the patient \200\231s needs Automatic volume control HEARING AIDS 553 Digital devices \200 Most health authorities have projects underway to \201 t digital h earing aids for all new referrals and exchange old analog aids. All but the most expensive are funded by the NHS where clinically indicated, and it is likely that a suitable device w ill be provided for most Most expensive, most advanced, with the highest amount of sound processing Programmable with \202 exible digital circuits that manipulate each sound according to pi tch and volume to give the clearest sound for that individual Higher clarity of sound, less circuit noise, faster processing, and automatic volume control Disposable devices \200 \200\230One size \201 ts all \200\231 \200\224 actually \201 t around 70 % of patients \200 Widely available, eg in pharmacies \200 Not individ ually tailored, so less good \200 No need for battery changes, low breakdown costs \200 Last about 40 days, so expensive in the long term Cochlear implants \200 Unilateral coch lear implantation is recommended as an option for people with severe to profound deafness who do not receive adequate bene \201 t from acous tic hearing aids Requires MDT assessment prior to insertion \200 Simultanous bilateral implants may be con sidered where there is coexistent blindness, making the patient more reliant on aural input 554 CHAPTER 21 Ears HOW TO Use a hearing aid To check a hearing aid \200 Put a new battery in \200 Turn to the \200\230M \200\231 s etting \200 Turn the volume up as far as it will go \200 A working hearing aid will whi stle Putting it in \200 The audiologist will take an impression of the ear to make an ear mold that \201 ts snugly This should be inserted so that it \201 ts correctly and comfortably Turning it on \200 Most hearing aids have three settings: \200\230O \200\231 = off; \200\230M \200\231 = mi crophone (use this setting for normal conversation); \200\230T \200\231 = telecoil (use th is setting with listening equipment, such as loop devices. These transfer sound direct to t he hearing aid and cut out background noise) \200 In addition, there will often be a volu me wheel, which can be adjusted as needed What to do if there is no sound \200 Check the hearing aid is not switched to \200\230O \200\231 or \200\230T \200\231 \200 Check the batteries are not dead, or put in upside d own \200 Check the mold is not clogged with wax \200 Check the tubing is not wet (dry w ith hairdryer) or twisted What to do if there is a whistling or squealing noise (feedback) \200 Occurs when the ear mold is not snug, allowing sound to escape into the microphone \200 Worse at high volumes \200 Check that the ear mold is a good \201 t (return to audiologist if not), and is inserted correctly Ensure there is not excess earwax impeding \201 t \200 Try turning the volume down Main taining the hearing aid \200 Handle carefully \200 Keep the hearing aid dry, away from strong heat or light \200 Use a clean dry tissue to clean, never a damp cloth \200 Use wax remover on a regular basis If the ear mold is separate (eg behind-the-ear) then periodi cally remove and wash with warm soapy water, ensuring it is totally dry before reconnecting it. This page intentionally left blank 556 CHAPTER 21 Ears Tinnitus The perception of a sound in one or both ears, without an external stim- ulus. Int ermittent or continuous. Varying kinds of noises (ringing, humming, buzzing, occasionally o ther noises) and at varying pitches. Large spectrum of disease. More common in men than wom en and incidence rises with age. Up to a fourth of older people may experience intermittent symp- toms. About a sixth of these will \201 nd it bothersome, and 1:20 will be disa- bl ed by it. A fourth of patients will get worsening symptoms with time. Tinnitus can be due to actual sounds that are generated by local structures: \200 Vascular structures (aneurysmal vessels, vascular tumors, etc. \200\224 generate a pulsatile or humming noise that may worsen with exercise) Muscle spasms (palatal or middle ear muscles \200\224 generate a clicking noise. Usually indicates underlying neurological disease) Eustachian tube may be patulous (can occur after dramatic weight loss) resulting in a roaring sound Joints (eg temporomandibular joint, cervical spine joints) More commonly, the noise is gene rated from somewhere within the auditory pathway (cochlear organ, nerve, brain stem or audi tory cortex) after some sort of damage or injury. The following are associated with tinnitu s: \200 Hearing loss \200\224 a very common cause in older people. Mechanism unclear \200\224 may be akin to phantom limb pain. Note tinnitus may precede deafness. May be assoc iated with conductive (eg wax accumulation) or more commonly sensorineural deafness (includ ing presbyacusis). Treatment of deafness (with hearing aid or occasionally cochlear implant ) often results in improvement of tinnitus Drugs \200\224 many commonly prescribed drugs in older people can either cause or exacerbate tinnitus (see Box 21.1 ) Vascular disease \200\224 microvascular damage to the auditory system, or a stroke affecting the auditory cortex. Modify vascular risk factors to limit progression Infection \200\224 eg chronic otitis media. Treat the cause, but may have residual problems Other \200\224 M ni re \200\231s disease, diabetes, thyroid disease, Paget \200\231s dis ease, brain tumor (intracanalicular and cerebello-pontine), trauma, and autoimmune disease. Treat underlying cause History \200 Obtain a description of tinnitus. This may indicate cause, eg pulsatile nois e is often vascular; clicking noise is often due to palatal muscle spasms; high-pitched con tinuous noise is usually due to sensorineural hearing loss; low-pitched continuous noise is more commonly seen (but not exclusive to M ni re \200\231s disease) Screen for possible causes (drug history, ear disease, noise exposure, injury etc.) Examination Should include full head and neck examination, cranial nerve examination, auscu ltation for bruits and inspection of the auditory canal. TINNITUS 557 Investigation Check FBC, glucose, and thyroid function. Refer to specialist for full audi- ometric assessment and possible imaging especially if unilateral (MRI angiography). Treatment \200 Dif \201 cult and frustrating \200\224 often best done in specialist cli nics with multidisciplinary team support Stop all ototoxic medication and avoid in future \200 Assess whether caffeine, aspartame sweetener, alcohol, nicotine and marijuana worsen tinnitus and avoid if so Treat the cause wherever possible \200 Strong association with insomnia and depression, b oth of which worsen the suffering and should be treated. Some evidence to suggest that antidepressants ( SSRIs) may help even when there is no overt depression Many other treatments have been tried (eg lidocaine, magnetic and ultrasonic stimulation, m elatonin, Ginkgo biloba , niacin, and zinc) but limited evidence they work and adverse effe cts common Hearing aids are useful if hearing loss \200\224 the increased awareness of the background sound tends to make the noise less apparent Masking techniques involve wearing a \200\230white noise \200\231 generator, rather like a hearing aid that aims to distract the patient from the tinnitus by reducing the contrast b etween the tinnitus signal and background noise, improving the plasticity of the central au ditory cortex and thereby facilitating a reduction in perception of the sound Mainstay of treatment is aimed at adjusting patients \200\231 perception of the tinnitus, t rying to habituate them to the noise and limiting the negative emotions it generates. Inclu des tinnitus retraining therapy, biofeedback, stress reduction techniques and cognitive and behavioral therapy Tinnitus support groups can be helpful ( M www.tinnitus.org.uk ) Box 21.1 Drugs causing or exacerbating tinnitus \200 Aspirin (high dose) \200 Other NSA IDs \200 Loop diuretics \200 ACE inhibitors \200 Calcium channel blockers \200 Doxa zosin \200 Aminoglycoside antibiotics \200 Clarithromycin \200 Quinine and chloroquin e \200 Carbamazepine \200 Tricyclic antidepressants \200 Benzodiazepines \200 PPIs \200 Some chemotherapy agents 558 CHAPTER 21 Ears Vertigo De \201 nition Vertigo is the hallucination of movement. A sensation of rotatory m otion either of the patient with respect to the environment ( \200\230its like being on a r oundabout \200\231), or the environment with respect to the patient ( \200\230the room is s pinning \200\231). The key element is a feeling of motion, without which a clinical diagnos is of vertigo should not be made. Understanding vertigo The vestibular system comprises the temporal bone labyrinths (compose d of the semicircular canals, the saccule, and the utricle), the vestibular nerve and the c entral vestibular structures in the brainstem. Normally, there is a constant input from bot h ears updating the central structures on head position. In the brainstem they are integrat ed with inputs from the visual cortex and from proprioceptive receptors (most important are neck and ankles). Any interruption of this signal leads to an excess of information from the good side, and s o an acute feeling of dizziness and nausea (vertigo) along with disruption of the vestibulo -ocular re \202 ex (which will cause nystagmus). This situation continues until either inp ut is restored, or the vestibular system adapts to the altered balance of signals. Adaptation means that: Vertigo is not a chronic condition. Multiple recurrences may occur, but a complaint of longstanding continuous dizziness is not vertigo. Vertigo rarely occurs with slowly progressive conditions (eg acoustic neuroma) as adaptation occurs along the way