Hearing and ENT








After reading this chapter you should be able to assess, diagnose and manage




  • hearing impairment



  • conditions affecting the ears, nose and throat including epistaxis




Hearing Impairment


Paediatric hearing impairment impacts negatively on the speech, language, social, emotional and educational development of a child and should be considered as a cause in any child with speech, learning or behavioural difficulties. Prevention, timely diagnosis and early intervention of hearing loss can prevent further disability in development of linguistic, academic and social skills.



Practice Point—description of hearing impairment (dBHL)





  • mild 26 to 40



  • moderate 41 to 70



  • severe 71 to 90



  • profound more than 90



dBHL—decibel hearing loss



Hearing Testing


A number of hearing assessments are available for children and the choice of these are dictated by the developmental age of the child.



Practice Point—hearing assessment by age





  • newborn hearing screening




    • automated otoacoustic emission (aAOE)



    • automated auditory brainstem response (aABR)




  • 6–18 months




    • visual reinforcement audiometry (VRA)




  • 2–5 years old




    • play audiometry




  • 5 years–adults




    • pure tone audiometry (PTA)





Newborn Hearing Screening Tests


Newborn hearing screening is a universal programme that aims to identify permanent moderate, severe and profound deafness and hearing impairment in newborn babies. The test can be done on babies up to the age of 3 months.


Early detection and early intervention of hearing problems will lessen the impact of deafness on the child, the child’s family and society. All well babies undergo an automated otoacoustic emission test (aOAE). If this is not “passed” after two attempts, then the baby has an automated auditory brainstem response test (aABR). Babies in the neonatal intensive care or at high risk and have both an aOAE and an aABR test.


Acoustic emissions are sounds that are produced by the outer hair cells of the inner ear in response to a noise stimulus and can be measured by placing a small probe in the ear canal. Since the sounds are only produced by normal outer hair cells, their detection correlates highly with normal hearing. The vast majority of hearing impairment is due to damage of these cells and the test therefore provides a sensitive and accurate means of screening for cochlear hearing impairment.


Auditory brainstem response is an electrophysiological response that measures the function of the auditory pathway from the external ear to the brainstem when sounds are presented to the ear. It can determine hearing thresholds allowing targeted treatment depending on the severity of the hearing thresholds.


Visual Reinforcement Audiometry


The test provides a “visual reward” when a child responds correctly by turning their head to sound played from headphones or field speakers on either side of the child and hearing thresholds are determined at different frequencies and amplitudes.


Play Audiometry


This test requires the child to respond to a sound by performing a simple task such as putting a ball in a bucket. This is repeated across different frequencies and at different volumes to determine the hearing thresholds.


Pure Tone Audiometry


The child usually wears headphones and is asked to respond when they hear the sound by pressing a button. The volume and frequency of the sound is adjusted to determine the hearing thresholds.


Tympanometry


The test assesses the status of the middle ear by measuring mobility of the eardrum. It is not a hearing test but an assessment of the compliance of the eardrum.


Types of Hearing Loss


The aetiology of paediatric hearing loss can be classified as congenital or acquired. Congenital hearing loss is present at birth and is due to genetic, prenatal or perinatal factors.


The type of hearing loss depends on where in the auditory pathway the impairment occurs. There are three basic types of hearing loss ( Figure 18.1 ).




Fig. 18.1


Pure tone audiograms of normal, conductive, sensorineural and mixed loss.


Conductive Impairment


Conductive hearing loss occurs when there is impairment of the sound transmission through either the outer or middle ear or both. Formal testing demonstrates that the bone conduction thresholds are better than air conduction thresholds. Conductive hearing loss produces losses of up to 50–60 dBHL.


The causes include:




  • ear canal obstruction—atresia, wax, foreign body



  • perforation of tympanic membrane



  • otitis media with effusion



  • Down syndrome



  • cranio-facial anomalies—Pierre Robin syndrome, cleft palate



Sensorineural Impairment (SNHL)


Sensorineural hearing loss is due to impairment within the inner ear or sensory organ (cochlea and associated structures) or the vestibulocochlear nerve (cranial nerve VIII). Formal testing demonstrates that both bone conduction and air conduction thresholds are poor. It can be more severe than conductive impairment and can also be progressive.


The causes include:




  • congenital SNHL




    • genetic—syndromic or nonsyndromic



    • infection—congenital infections



    • prematurity



    • hypoxic ischaemic encephalopathy




  • acquired SNHL




    • ototoxic drugs—aminoglycosides, furosemide



    • meningoencephalitis



    • head injury



    • neurodegenerative disorders



    • hyperbilirubinemia




The hearing loss in sensorineural impairment is usually profound and usually greater than 90 dBHL. The children need prompt referral to ENT services for a more detailed assessment and consideration of the need for a hearing device. Aminoglycosides classically induce a high-tone hearing loss with a ‘ski slope’ appearance on the audiogram.


Mixed impairment


Mixed hearing loss occurs when a conductive loss is superimposed on a sensorineural loss. Hearing assessment shows air conduction thresholds to be poorer than bone conduction thresholds, but when the conductive element resolves, the air conduction thresholds revert to bone conduction levels.


Treatment and management


The underlying cause for the loss of hearing will guide the management plan. Most children with conductive loss should be referred to ENT services where they will be managed conservatively or with hearing aids. Full resolution of the problem is likely although some may need surgery. It is important that parents understand the potential effect of the hearing loss on the child’s ability to communicate and so accept the importance of wearing hearing aids.


Any child with identified SNHL should be referred promptly to an ENT service to assess for hearing restoration or rehabilitation. Congenital SNHL needs investigations aimed at identifying the aetiology.


Any child diagnosed with a streptococcal meningitis should have an urgent referral to ENT services as this infection leads to time-critical ossification of the cochlea and any delay will reduce the benefit of cochlear implantation.


Involvement of the multidisciplinary team for children with hearing difficulties will utilise the different skills of the audiologist, parent, ENT specialist and speech and language therapist with later involvement of the teacher once options for preschool and schooling are discussed.


Conditions Affecting Ears, Nose or Throat


Otitis Media


Otitis Media with Effusion


This diagnosis describes an accumulation of fluid behind an intact tympanic membrane in the absence of symptoms and signs of an acute infection. Commonly referred to as ‘glue ear’, it is the most common cause of hearing difficulties in childhood and is more common between the ages of 2–7 years. On examination, the eardrum looks dull with loss of its light reflex and a fluid level or bubbles may be observed.


Treatment and management


Intervention in a child with otitis media and an effusion is indicated if there is hearing loss of 25–30 dBHL in the better hearing ear on two occasions, 3 months apart. Most problems resolve over this time although they do require follow up to ensure the hearing returns to normal. If there is no improvement in the hearing then hearing aids or the insertion of grommets will be considered and, in some, adenoidectomy may be of benefit.


Acute Otitis Media


Acute otitis media (OM) is a common infection in childhood and presents with ear pain, fever and irritability but in younger children the infection may lead to pulling of the ear or banging of the head. Purulent otorrhoea may occur following perforation and otoscopy may be difficult if the external canal is full of pus. The diagnosis is made by direct observation when a red bulging tympanic membrane is seen along with loss of normal light reflex and an effusion behind the membrane.


Bacteria cause the majority of infections in acute OM and the common organisms are:




  • Streptococcus pneumoniae



  • Haemophilus influenzae



  • Moraxella catarrhalis



  • Group A streptococcus



  • Staphylococcus aureus



Viruses causing acute otitis media are RSV and rhinovirus and therefore symptoms may be seasonal.


Treatment and management


Pain relief with regular paracetamol and ibuprofen is important. Antibiotic management remains controversial as spontaneous recovery occurs in 80% of children and they do not alter outcomes with regards to risk of complication (perforation or mastoiditis). Amoxicillin may be considered in those under 1 year if the child has a high temperature or fails to improve in 2–3 days. Antihistaminic and decongestants are not effective. Risk of serious complications such as mastoiditis and meningitis are recognised but rare consequences for acute OM.


Epistaxis


Epistaxis is common in children and usually the result of local trauma. Little’s area describes a venous plexus on the nasal septum and is the most common origin of the bleed. If there are recurrent nose bleeds with bruising or family history of bleeding disorders, then alternative diagnoses should be considered and would include:




  • coagulation disorders



  • leukaemia



  • foreign body



  • hypertension



Pressure on the nose below the nasal bone will usually stop the bleeding, but if this fails and the bleeding is profuse then nasal packing or cauterisation may be necessary.


Tonsillar Hypertrophy


This is a common finding in children and usually causes minimal problems. Tonsillar tissue increases in size during the first 6–7 years of life before gradually involuting and, by late teenage years, is usually vestigial. If, however, they undergo massive and sustained enlargement, they may lead to clinical problems such as sleep apnoea.


Children with significant tonsillar hypertrophy will usually present with noisy breathing at night with loud snoring that, on occasions, can be heard in other parts of the house. The child may have observed apnoeic episodes that lead to disturbed and interrupted sleep and consequent daytime tiredness. This, in turn, may lead to a deterioration in behaviour and educational attainment. With more extreme and delayed presentation, the child may have developed chronic hyperoxia, pulmonary hypertension and right ventricular hypertrophy. Further details on investigation and management of sleep disorder breathing can be found in Chapter 17 Respiratory.


Pharyngotonsillitis


Pharyngotonsillitis is usually caused by a viral or bacterial infection and therefore peaks in winter months. The most common viral organisms responsible are rhinovirus, adenovirus, influenza, parainfluenza and Epstein-Barr and the most common bacterial agents are streptococcus group A and C. Viral infections usually last 3–5 days with gradual improvement. However, if the symptoms do not improve after 2–3 days, review is needed, and consideration should be given for a bacterial aetiology.


Clinical presentation


Children often present with fever, sore throat, cough and painful swallowing. Examination shows hyperaemic or inflammation in the posterior pharyngeal wall, uvula and tonsils and the latter may have white exudates covering them. It is not possible to distinguish bacterial from viral infection on clinical examination alone.


Investigations


Throat swabs cannot distinguish current streptococcal disease from carriage and are not routinely undertaken in children with tonsillitis. When a child has obvious high fever and exudative tonsils lasting more than 48 hours then a throat swab may help future management.


Treatment and management


The usual practice would be for symptomatic support with antipyretic medication only. Antibiotics are rarely needed and confer minimal advantage in settings with a low incidence of recognised complications. A 10-day course of penicillin would be advisable if symptoms worsen or the child has a past history of rheumatic fever or a chronic illness that impacts on immune function. Recurrent episodes of tonsillitis which impact on school attendance and learning may need an ENT opinion regarding the need for tonsillectomy.


A peritonsillar abscess is an uncommon complication of pharyngotonsillitis where pus collects in between the tonsil and pharyngeal wall muscles. The child will present with increased pharyngeal pain, local swelling, ‘hot-potato’ voice, odynophagia, otalgia and trismus. The condition can rapidly progress to airway obstruction and requires treatment with surgical drainage and antibiotics.


Jul 31, 2022 | Posted by in PEDIATRICS | Comments Off on Hearing and ENT
Premium Wordpress Themes by UFO Themes