The effects of anesthesia on otoacoustic emissions

We have measured transient-evoked and distortion-product otoacoustic emissions (OAEs) in the chinchilla and compared them in the awake and anesthetized animal (using either ketamine or barbiturate agents). We report a significant increase in OAE amplitudes during anesthesia, particularly using ketamine. These effects are most evident for transient-evoked otoacoustic emissions (TEOAEs) as measured in the non-linear mode. Our data support the hypothesis that tonic activity levels in cochlear efferents may be reduced by anesthetic effects, either directly or indirectly (e.g., by general reductions in descending pathway activity), and that reduced cochlear efferent activity will result in the observed increase of OAE amplitudes.     

Defining and predicting tracheoesophageal puncture success.

There is considerable variability in the reported success rates of tracheoesophageal puncture due, in part, to the lack of a clear definition of success and a paucity of knowledge about factors that determine success. In this article, we define success on a continuum with the use of a 15-point rating scale that incorporates aspects of use and quality of speech and ability to care for the fistula and prosthesis. We suggest a cutoff score for functional and nonfunctional speakers. We define immediate and short- and long-term success. Variables related to the patient, clinician, surgical procedure, and extent of disease were subjected to a multiple regression analysis to determine which predicted success. Overall success was predicted by greater clinician expertise, younger patient age, and better patient health. We discuss the use of the rating scale and an equation to predict success.     

INTRA-AORTIC BALLOON RUPTURE CAUSING FEMORAL ENTRAPMENT

Rupture of an intra-aortic balloon counterpulsator (IABCP) demands immediate removal. We report a case of thrombus formation within a Datascope IABCP secondary to IABCP rupture, necessitating surgical exploration for removal. There is a disturbing pattern of balloon ruptures with this type of IABCP.     

Automated neuropsychological assessment metrics (ANAM) measures of cognitive effects of Alzheimer's disease.

Eight individuals with Alzheimer's disease, and eight age-matched controls, were administered the MMSE, the Yesavage GDS, and a customized subset of the Automated Neuropsychological Assessment Metrics (ANAM) Battery. Accuracy (percent correct) and efficiency (number of correct responses per minute) of performance on six ANAM tasks were assessed. The patients' GDS scores indicated no depression. Although their MMSE scores (mean approximately 25) were significantly lower than those of the controls, they nonetheless indicated that the patients were still functioning at a fairly high level. Analysis of ANAM accuracy scores indicated that the patients were significantly impaired on three tasks measuring working memory. A discriminant function analysis revealed 93.8% correct classification. Analysis of ANAM efficiency scores revealed that except for simple reaction time, the patients were significantly impaired on all tasks. A discriminant function analysis correctly classified 100% of the participants. Given the small size of the groups in the present study, this finding especially underscores the sensitivity of ANAM to the cognitive effects of Alzheimer's disease, as indicated by the large effect sizes. The findings further indicate that ANAM might be capable of detecting more subtle effects of the disease at an earlier stage in its progress.     

Pneumoperitoneum

Pneumoperitoneum results from perforation of the gastrointestinal tract in the majority of instances and the necessity of operative treatment is implied. In patients where peritonitis is not a problem, nonoperative treatment is successful. Surgical treatment is not required for those in whom the condition results from barotrauma. The decision to enjoin or withhold operative intervention in individual cases is judgmental.     

Sausage resection of ischemic intestine

In a critically ill neonate, simple ligation of intestinal segments to be preserved for a second look procedure allows expeditious resection of intervening necrotic segments.