C. William Erwin

A five week, polysomnographic assessment of zaleplon 10 mg for the treatment of primary insomnia

Objective: To examine the hypnotic efficacy of zaleplon 10 mg, a selective benzodiazepine receptor agonist, over a period of 35 nights in primary insomniacs.Methods: A double-blind, parallel-group, placebo-controlled design was employed. Subjects were 113 men and women, ages 18 to 65 years. Polysomnographic and subjective sleep data were collected during baseline, on two nights during each of five treatment weeks, and on the first two nights after discontinuation of active medication.Results: Sleep latency was significantly shortened with zaleplon 10 mg for all 5 weeks of treatment as assessed by polysomnography and by subjective sleep measures. Total sleep time, whether evaluated with polysomnography or with subjective estimates, was inconsistently affected. Sleep architecture was similar with zaleplon and placebo. There was no evidence of tolerance to the sleep promoting effects of zaleplon during the five weeks of administration, and there was no rebound insomnia upon discontinuation. Adverse events occurred with equal frequency in the zaleplon and placebo groups.Conclusions: Zaleplon 10 mg is effective in the treatment of sleep onset insomnia over a period of 35 nights, with minimal evidence of undesired effects.

Ambulatory polysomnography: Technical aspects and normative values

Ambulatory polysomnographic (APSG) assessment of sleep disorders is now possible, but the technique of APSG is sufficiently different from in-laboratory PSG that normative data from in-laboratory PSG may not apply to APSG. This paper reviews the technical aspects of APSG and presents normative APSG data from 20 older healthy males. Subjects underwent medical and psychiatric screening before completing APSG in their homes. Total sleep time and the rapid-eye-movement sleep latency (RL) were both shorter than those reported by others using traditional in-laboratory techniques. The shorter total sleep may be related to behaviors at home that impinge upon sleep. The shorter RL may be related to differences in calculation methods. Periodic limb movements were common in our subjects but did not contribute to sleep disturbance. We conclude that APSG is sufficiently different from traditional PSG as to warrant collection of a large normative data base.

Effects of ethanol and psychomotor tests on state anxiety: interaction with menstrual cycle in women.

10 non-alcoholic women (ages 20 to 25 yr.) were administered drinks containing ethanol 0.0, 0.5, 0.8, and 1.2 g/kg. They then performed four complex psychomotor tasks. Immediately prior to drinking and after completing the tasks they were given the Spielberger State-Anxiety Inventory. Women were tested both during follicular and the luteal phases of their menstrual cycle. A significant positive correlation was found between increments in anxiety scores and blood ethanol levels in the luteal but not in the follicular phase.

Somatosensory evoked potentials in a patient with a cervical glioma and syrinx

Short-latency somatosensory evoked potentials (SSEPs) were obtained in a 61-year-old patient with a cervical spinal cord glioma extending from C3 to C7. SSEPs in response to tibial nerve stimulation were normal; however, all components of the median nerve responses were markedly abnormal bilaterally (except for normal brachial plexus responses). This selective abnormality of median nerve SSEPs has not been reported previously in a patient with cervical cord tumor associated with a syrinx and illustrates the use of the SSEP in the anatomical localization of the lesion.

Ambulatory cassette polysomnography: findings from a large cohort of drug-free insomnia patients.

Technology for conducting ambulatory polysomnography (APSG) has been available for more than a decade, but relatively few studies have used this technology to study the sleep of subjects in their usual home sleeping environments. Herein we suggest the usefulness of this technology for the study of normal sleepers and insomniacs, and we report our APSG findings with a large cohort (n = 117) of drug-free insomnia outpatients. All patients completed a sleep-history questionnaire, a clinical interview with a sleep-disorders clinician, and one night of APSG in their homes. Most sleep parameters derived were consistent with previously reported laboratory PSG findings for insomniacs, except that values of rapid-eye-movement sleep latencies were generally shorter than typically found in laboratory studies. Moreover, results showed that APSG served to differentiate major age groups and diagnostic subtypes within our larger sample, and patient tolerance for APSG was within acceptable limits. We conclude that APSG is a useful technique for evaluating insomnia complaints.

Evaluation of transducers for obtaining intraoperative short-latency auditory evoked potentials.

Operative monitoring of short-latency auditory evoked potentials during posterior fossa surgery requires audio transducers of small physical size so as to not interfere with the operative field. There are many relatively inexpensive transducers in the commercial audio hifi market of appropriate size. Some produce suitable biological responses and tolerate long term use without failure. The authors describe factors to consider and methods used in testing such transducers.

Ambulatory Cassette Polysomnography

Publisher Summary This chapter provides an overview of the ambulatory cassette polysomnography (PSG) technique. A multichannel cassette recorder suitable for PSG became available in 1971, and the first report of successful ambulatory PSG came 2 years later. Since then, the growth and acceptance of ambulatory PSG have progressed as techniques, indications, and limitations have been clarified. Ambulatory PSG implies freedom of movement for the patient. Ambulatory cassette PSG complements other standard laboratory assessments of sleep apnea, primary hypersomnias, and insomnia. In disorders of excessive daytime sleepiness, its primary utility is in diagnosis of suspected severe sleep apnea, follow-up assessment after intervention for sleep apnea, or preliminary overnight PSG before multiple sleep latency test. Ambulatory PSG may be used as the primary tool for evaluating insomnia. Its advantages include patient comfort and convenience, potential cost savings, ease of sleep stage scoring with the auditory transformation of the EEG, and simplicity of data handling and storage. Success in achieving interpretable studies hinges on the diligence of the technician. Liabilities of the ambulatory PSG are the absence of a technician to make technical corrections and behavioral observations and the limited number of channels.