The Pittsburgh Sleep Diary

SUMMARY  Increasingly, there is a need in both research and clinical practice to document and quantify sleep and waking behaviors in a comprehensive manner. The Pittsburgh Sleep Diary (PghSD) is an instrument with separate components to be completed at bedtime and waketime. Bedtime components relate to the events of the day preceding the sleep, waketime components to the sleep period just completed. Two-week PghSD data is presented from 234 different subjects, comprising 96 healthy young middle-aged controls, 37 older men, 44 older women, 29 young adult controls and 28 sleep disorders patients in order to demonstrate the usefulness, validity and reliability of various measures from the instrument. Comparisons are made with polysomnographic and actigraphic sleep measures, as well as personality and circadian type questionnaires. The instrument was shown to have sensitivity in detecting differences due to weekends, age, gender, personality and circadian type, and validity in agreeing with actigraphic estimates of sleep timing and quality. Over a 12–31 month delay, PghSD measures of both sleep timing and sleep quality showed correlations between 0.56 and 0.81 ( n = 39, P < 0.001).     

Monitoring normal and aberrant electrocardiographic activity from an endotracheal tube: Comparison of the surface,esophageal, and tracheal electrocardiograms

Introduction. We designed an endotracheal (ET) tube with orthogonally spaced ECG cuff electrodes. This ET tube was evaluated in dogs and sheep to determine (1) whether ECGs recorded from our tube were sufficient to make accurate clinical decisions concerning heart rate and rhythm; and (2) whether metallic cuff electrodes in direct contact with the trachea could induce mucosal burn injury during episodes of defibrillation.Methods. Using experimental animals, we obtained ECGs from their tracheae and compared our findings with ECGs obtained from surface and esophageal electrodes. The electrical activity of the heart was modified by increasing the depth of anesthesia, occluding the left coronary artery, and administering beta-adrenergic drugs. Before the dogs were euthanized, they were subjected to episodes of transthoracic and intrathoracic defibrillation at energy levels of 200 to 400 J. A postmortem pathological examination of the trachea was performed to determine the incidence of mucosal burn injury.Results. Tracheal electrocardiography provided valid information on heart-rate monitoring and certain morphology profiles. The R-R, PR, QRS, and QT intervals measured from the trachea had a correlation of 1.0, 0.96, 0.83, and 0.98, respectively, when compared with the same intervals obtained from surface electrodes. Two tracheae subjected to intrathoracic defibrillation at >300 J revealed evidence of minor burn injury. Some localized epithelium loss was displayed in all tracheae; we attributed this to tracheal intubation.Conclusion. Tracheal electrocardiography may be useful in trauma patients who require intubation where injury precludes placement of chest ECG electrodes.     

4-Aminopyridine and spinal cord injury: a review

Demyelination of axons within the spinal cord represents a significant component of the pathology of contusive and compressive spinal cord injury (SCI) and the associated conduction deficits most probably contribute to the paralysis and sensory loss experienced by SCI patients. 4-Aminopyridine (4-AP) is a potassium (K+) channel blocking agent that has been shown capable of restoring conduction across demyelinated internodes in neurons of the spinal cord. Recent clinical trials of 4-AP provide evidence that limited and transient neurological gain may be derived by some SCI patients with longstanding injury. The present review traces the historical development of 4-AP, describes the mechanism of action and rationale for use in SCI, and provides an overview of the clinical trials conducted to date. The early trials give rise to optimism that pharmaceutical management of conduction deficits may have a role to play in restoring neurological function in some patients with SCI.     

Adverse reactions to an absorbable shoulder fixation device

Bioabsorbable implants have been advocated for use in repair of a torn glenoid labrum to correct shoulder instability. These implants have been thought to be safe and to have little toxicity, antigenicity, or adverse side effects. However, similar implants have been shown to cause nonspecific granulomatous reactions when implanted into bone or soft tissues in studies in both animals and human beings. This article reports the adverse effects of these implants in six shoulders of five patients who had repair of a damaged glenoid labrum. All patients reported increasing pain and loss of shoulder motion after insertion of these devices. All required a further arthroscopic lavage and debridement to reduce the inlracapsular synovitis. Granulomatous reactions were identified histologically in all cases. No long-term side effects were encountered, and all patients recovered satisfactorily.     

The role of the principal clinical coordinator in the Health Care Financing Administration's Health Care Quality Improvement Initiative

The Health Care Quality Improvement Initiative (HCQII) is the Health Care Financing Administration's latest approach to quality management by peer review organizations (PROs) of the health care delivered to Medicare beneficiaries. The principal clinical coordinator (PCC) of each PRO, a physician with both clinical and methodological expertise, has the overall responsibility for all HCQII-related activities. The PCC works with a clinical coordinating team to analyze patterns of care and provide feedback about these patterns to the medical community for the purpose of improving the quality of care. Each PRO provides its PCC with the necessary infrastructure and expertise to conduct pattern analyses and implement the dissemination process. However, the effectiveness of the HCQII will depend largely on the PCC's ability to maintain the full support and cooperation of the local medical community. The success of the PCC role under the HCQII may enable it to serve as a useful model of physician leadership in the quality oversight organizations that will accompany national health care reform.     

Safety of <7500 RE (<25000 IU) vitamin A daily in adults with retinitis pigmentosa

BACKGROUND: Vitamin A supplementation is being used successfully to treat some forms of cancer and the degenerative eye disease retinitis pigmentosa. The daily biological need for vitamin A is estimated to be 800 retinol equivalents (RE)/d (2667 IU/d) for adult women and 1000 RE/d (3300 IU/d) for adult men; doses > or = 7500 RE (> or = 25000 IU)/d are considered potentially toxic over the long term. OBJECTIVE: We assessed the safety in adults of long-term vitamin A supplementation with doses above the daily biological need but <7500 RE (<25000 IU)/d. DESIGN: Adults aged 18-54 y with retinitis pigmentosa but in generally good health (n = 146) were supplemented with 4500 RE (15000 IU) vitamin A/d for < or = 12 y (group A) and compared with a similar group (n = 149) that received 23 RE (75 IU)/d (trace group). Mean total consumption of vitamin A in group A was 5583 RE (18609 IU)/d (range: 4911-7296 RE/d, or 16369-24318 IU/d) and that in the trace group was 1053 RE (3511 IU)/d (range: 401-3192 RE/d, or 1338-10638 IU/d). RESULTS: Patients in group A showed an 8% increase in mean serum retinol concentration at 5 y and an 18% increase at 12 y (P < 0.001); no retinol value exceeded the upper normal limit (3.49 micromol/L, or 100 microg/dL). Mean serum retinyl esters were elevated approximately 1.7-fold at 5 y and remained relatively stable thereafter. No clinical symptoms or signs of liver toxicity attributable to vitamin A excess were detected. CONCLUSIONS: Prolonged daily consumption of <7500 RE (<25000 IU) vitamin A/d can be considered safe in this age group.