Faculty Bibliography

Cochlear implants can restore hearing to deaf individuals by electrically stimulating the auditory nerve. They do so by assigning different frequencies to different stimulating electrodes via a frequency map. We have developed a device that enables us to change the frequency map in real time. Here, in normal-hearing adults listening to an acoustic simulation of a cochlear implant, we investigate what frequency maps are initially preferred, and how the ability to understand speech with that preferred map compares with two other maps. We show that naive listeners prefer a map that balances the need for low-frequency information with the desire for a naturally-sounding stimulus, and that initial performance with this listener-selected map is better than that with a map that distorts the signal to provide low-frequency information

OBJECTIVES: Consultations for tracheotomy are often sought on aged and severely ill patients with respiratory insufficiency. This patient population has high short-term mortality rates and is difficult to stratify on the basis of expected outcome. We examined whether APACHE III (Acute Physiology and Chronic Health Evaluation III) scores or neurologic status assessment (NSA) scores in sedated individuals are predictive of outcome. METHODS: We performed a retrospective study examining aged patients who underwent tracheotomy for respiratory insufficiency and prolonged intubation. The APACHE III scores (n = 30) and NSA (based on a modified Glasgow Coma Scale) scores (n = 37) were calculated before tracheotomy. All patients were mildly sedated. Using APACHE III and NSA scores as predictor variables and using death and ability to be weaned from the ventilator as outcome variables, we performed a Kaplan-Meier survival analysis and a Cox proportional hazard regression. RESULTS: The APACHE III was not significantly predictive of either outcome. Higher NSA scores were associated with increased survival rates (log rank = 19.7, p < .0001) and longer median survival (88 days versus 16 days for lower scorers). Higher NSA scores also predicted a higher rate of ventilator independence. CONCLUSIONS: Neurologic function in sedated patients (and not APACHE III scores) can be used to stratify aged individuals with respiratory insufficiency on the basis of expected outcome