If all infants were screened for hearing loss using the 2-stage OAE/A-ABR newborn hearing screening protocol currently used in many hospitals, then approximately 23% of those with PHL at approximately 9 months of age would have passed the A-ABR. This happens in part because much of the A-ABR screening equipment in current use was designed to identify infants with moderate or greater hearing loss. Thus, program administrators should be certain that the screening program, equipment, and protocols are designed to identify the type of hearing loss targeted by their program. The results also show the need for continued surveillance of hearing status during childhood.

Auditory neuropathy (AN) is a condition in which transmission of sound to the brain is abnormal. This is reflected as an electrophysiologic profile of normal otoacoustic emissions (OAE), with abnormal auditory brainstem evoked responses (ABR). Functionally speech perception is impaired and management strategies remain controversial. AN can be missed if high-risk newborns are screened for hearing loss with only OAE testing. The rate of sensorineural hearing loss (SNHL) in high-risk nursery infants is 10 times greater compared with normal term newborns. Therefore, we hypothesize that infants from the neonatal intensive care unit (NICU) are at significantly higher risk for AN than normal term infants.Objective: The objective of this study is to establish a prevalence rate and characterize risk factors for NICU graduates who demonstrate the AN electrophysiologic profile.Study Design: This retrospective study examined infants admitted to the NICU at Kapi'olani Medical Center for Women and Children in Honolulu, HI from 1999 through 2003. Infants were screened with automated ABR. Diagnostic testing and OAE were performed before discharge if the ABR was abnormal. Hospital courses of 24 AN, 71 SNHL and 95 gestational age (GA)-matched control infants with normal hearing were reviewed.Result: With a SNHL prevalence of 16.7/1000, the rate for AN was 5.6/1000 NICU infants. Compared to infants with SNHL, infants with AN were significantly younger (GA 28.3±4.8 AN vs 32.9±5.2 weeks SNHL, P<0.0001) and smaller (BW 1318±894 AN vs 1968±1006 g SNHL).Nearly two-thirds of the AN infants were ELBW and had significantly longer hospital stays compared to SNHL infants of the same birth weight group. Exposure to furosemide, aminoglycosides, vancomycin or dexamethasone was associated with increased AN but not SNHL. Peak bilirubin level correlated with SNHL but not AN.Conclusion: Low birth weight NICU infants are at significant risk for AN. ELBW infants are at significantly higher risk for both AN and SNHL.Infants admitted to the NICU should be routinely screened by automated ABR and if abnormal, further evaluation should be started before hospital discharge. Early identification of AN will result in better understanding of this disorder and lead to the development of appropriate intervention strategies.

The study found that the 2-stage OAE/A-ABR protocol did miss a significant number of babies who exhibited a permanent hearing loss by 1 year of age. Three subsequent articles will describe the research design and results in detail, discuss the behavioral assessment of infants, and summarize the implications of the study for policy, practice, and research.

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Objective. Universal Newborn Hearing Screening began in 2 Honolulu hospitals in 1992, and by 1999, all 14 civilian birthing facilities in Hawaii were providing screening. Examination of 1998 Hawaii data indicated that approximately 13% of infants who did not pass initial hearing screening in the hospital did not return for the indicated follow-up. The purpose of this study was to determine the epidemiologic profile of infants who were born in 1999 and did not return for follow-up. Methods. A population-based, cohort study of the hearing screening completion rates among the 13 civilian birthing facilities in Hawaii that provided data to the Department of Health was conducted. Analysis included a bivariate analysis of the demographic characteristics of infants who completed the screening/follow-up process compared with those who did not and logistic regression modeling to ascertain the demographic profile of infants at high risk for being lost to follow-up. Results. Of 12 456 infants, hearing screening data could be linked to the birth certificate file, and a final disposition regarding completion of the screening/follow-up process was determined for 10 328 (83%). Less than 2% (n = 176) of the linked infants failed to complete the screening/follow-up procedures. Low birth weight and white infants and infants born to women who had not completed high school were approximately twice as likely not to complete the screening as were their normal birth weight or nonwhite counterparts. Conclusions. Failure to complete the hearing screening follow-up may be related to cultural differences that have been previously reported in other maternal and child health studies of the diverse populations in Hawaii. The results of this study will allow the Hawaii Newborn Hearing Screening Program to target its efforts and limited resources toward infants who are at higher risk of not completing the screening and who may need special attention to encourage their mothers to complete the screening process, and to move quickly with rescreening infants whose initial tests are positive so that infants are not lost to follow-up.