Newborn Hearing Screening
A newborn hearing screening assesses infants for adequate hearing levels.
Three out of 1,000 babies are born with permanent hearing loss, making congenital hearing impairment the most common birth defect. Without screening, children with dysfunctions in hearing are usually not identified until two and a half to three years of age and many are not diagnosed properly until five to six years of age. A postponement in diagnosis results in considerable delays in the attainment of essential speech, language, social, cognitive, and emotional development skills that are central to later success in school and life. Even children with a hearing impairment in one ear suffer significant detrimental effects and are more likely to be held back at least one grade when compared with a group of children without hearing impairments.
Because simple, cost-effective technology now exists to detect hearing loss in newborns, many hospitals have implemented universal screening programs. When diagnosed shortly after birth, infants can start to wear amplification devices as early as one month of age. Children who were identified prior to six months of age and received early intervention and amplification devices were found to be one to two years ahead in language, cognitive, and social skills as compared to children who were not identified early.
In 1993, the National Institutes of Health concluded that all newborns should receive screening for hearing impairment. Screening was determined to be most appropriate prior to discharge from the hospital.
Some hospitals screen only newborns who are at risk of hearing loss—about 10% of the population. Risk factors include a history of childhood hearing impairment in the family, infection (cytomegalovirus, rubella, herpes, toxoplasmosis, or syphilis), congenital malformations of the head or neck, weight at birth less than 3.3 pounds (1,500 grams), severe jaundice (hyperbilirubinemia), antibiotics, bacterial meningitis, and severe asphyxia at birth. Because research has indicated that only about half of children identified as having congenital hearing loss had any risk factors, and because of the availability of new screening techniques, many hospitals have adopted the universal hearing screening of newborns.
The majority of newborn hearing screening programs use one of three types of equipment: automated auditory brainstem response (AABR), distortion product otoacoustic emissions (DPOAE), or transient evoked otoacoustic emissions (TEOAE).
The general technique for the exam is to place an earphone or probe on the baby's ear and to attach an electrode to the scalp. A sound or click is then transmitted to the baby. A microcomputer or miniature microphone interprets the electrical potential created by the brainstem responding to the sound or the echo from the cochlea (located in the inner ear).
The cost of the equipment ranges from $4,000 to $25,000 for each individual unit. Training of personnel takes approximately two to four hours, and time involved to perform each test varies from 15 minutes to 40 minutes for each baby.
If the environment is quiet and the baby is restful, testing results will be the easiest to obtain.
Infants who do not appear to have adequate hearing at the screening should obtain a follow-up hearing evaluation before six months of age.
Results should be the detection of infant hearing loss. It is possible that mild hearing loss will not be detected.
Health care team roles
Any member of the health care team can be trained in administering the test. Generally, most hospitals have nurses involved in the screening process.
Asphyxia—A deficiency of oxygen or state of carbon dioxide over-saturation within the body.
Cochlea—A component of the bony labyrinth of the inner ear that is involved in hearing.
Pilliterri, Adele. Maternal & Child Health Nursing. 3rd ed. Philadelphia: Lippincott, 1999.
American Speech-Language-Hearing Association (ASHA). 10801 Rockville Pike, Rockville, MD 20852. (888) 321-ASHA. <http://professional.asha.org/index7.htm>.
National Center for Hearing Assessment and Management (NCHAM). Utah State University, 2880 Old Main Hill,
Issue Brief: Early Hearing Loss Detection, Diagnosis and Intervention. ASHA, 1999. <http://professional.asha.org/governmental_affairs/issue_walsh.htm>.
Selecting Equipment for a Newborn Hearing Screening Program. NCHAM, 2001. <http://www.infanthearing.org/resources/equipment.html>.
Universal Newborn Hearing Screening: Fact Sheet. NCHAM, 2000. <http://www.infanthearing.org/ehdi/screening.html>.
Nadine M. Jacobson, R.N.