Disability evaluation following traumatic brain injury

Accurate disability evaluation of a patient with TBI is a very difficult and detailed process. It requires an excellent background concerning the evaluation of all the physical, cognitive, behavioral, and functional abnormalities associated with TBI. Texts that highlight all these abnormalities include Medical Rehabilitation of Traumatic Brain Injury by Horn and Zasler and Rehabilitation of the Adult and Child with Traumatic Brain Injury by Rosenthal et al. In addition, appropriate disability rating can only be performed by a physician with expert skills in obtaining accurate historical information and completing a detailed physical examination. Often, the historical information must be obtained from many sources because the patient may supply inaccurate information because of his or her cognitive deficits. Interviews with family members, caregivers, therapists, friends, and employers are sometimes necessary to obtain an accurate historical picture. Premorbid functioning, behavior, and personality are important because previous abnormalities are often exaggerated after the TBI. The physical examination should be tailored to provide detailed objective information concerning all deficits identified through the history. If cognitive and behavioral problems are identified through either the history or examination, a neuropsychologic assessment is necessary. All this information should be available before the disability or impairment rating. Only with detailed information can a clinician provide an accurate rating.

Performance of a reservoir nasal cannula (Oxymizer) during sleep in hypoxemic patients with COPD

STUDY OBJECTIVE

To determine whether a reservoir nasal cannula (RNC) (Oxymizer) provides an arterial hemoglobin oxygen saturation as measured by pulse oximetry (SpO2) equivalent to that provided by the standard nasal cannula (SNC) during sleep in hypoxemic patients with COPD while reducing oxygen flow requirement and cost.

DESIGN

The study took place in a sleep laboratory for three nights, with the first night for acclimatization to the new sleeping environment. In a repeated-measures design, on the second and third nights, subjects used the SNC for one night and the RNC on another night. The order in which they received the two devices was counterbalanced.

SUBJECTS

The subjects were patients with COPD who had a stable PaO2 of 55 mm Hg or less or had a value of 56 to 59 mm Hg with evidence of cor pulmonale or polycythemia (or both) and an FEV1/FVC of less than 70 percent.

INTERVENTIONS

A pulse oximeter was used to measure SpO2. An arterial blood gas measurement was taken on each night while the patients with COPD were receiving oxygen therapy via the assigned device. An EEG machine was used to record measurements of electro-oculography, chin electromyography (EMG), anterior tibialis EMG and EEG.

MEASUREMENTS AND MAIN RESULTS

There was a statistically significant difference between mean SpO2 during sleep (RNC, 91 percent; SNC, 93 percent; F = 7.89; p = 0.01). Nocturnal SpO2 was less than 90 percent for 24.2 percent of the time with the RNC and for 17.5 percent of the time with the SNC (F = 5.41; p = 0.03), but there was no significant difference in the amount of time that SpO2 was less than 85 percent. Compared to the SNC, in 4 of 26 patients with COPD, the RNC performed better; in 12 patients with COPD, the RNC performed the same, and in 10 patients with COPD the RNC performed worse during sleep. Sleep parameters were not significantly different between the two devices.

CONCLUSIONS

The difference of 2 percent in mean SpO2 is within the range of SpO2 measurement error. Therefore, the two devices are equally effective when the sample is considered as a whole. Nighttime oximetry is necessary prior to prescription, since nighttime efficacy of the RNC cannot be predicted on the basis of daytime pulse oximetry.

The whole is greater than the sum of its parts: the anatomy of the Department of Veterans Affairs Medical District 17 Health Services Research and Development Field Program

The Medical District 17 Health Services Research and Development (HSR&D) Field Program was funded by the Veterans Administration (now the Department of Veterans Affairs--VA) in January 1983. This article describes the organization, progress, and accomplishments of this field program, and it provides a review of the breadth of health services research that is being conducted in Medical District 17. Overall, the field program has conducted research that addresses significant problems in the delivery of health care within the VA system. Resource utilization, cost effectiveness, and the care of geriatric patients have been some of the areas in which the Medical District 17 HSR&D Field Program has provided important research findings for VA. The field program plans to continue its response to the needs of VA. Moreover, HSR&D investigators will be collaborating with researchers of other services to conduct research that is both enlightening and highly relevant to the delivery of health care to the nation's veterans. The proposal for an HSR&D field program was developed by the Edward A. Hines Jr. VA Hospital in collaboration with the Center for Health Services and Policy Research (CHSPR) of Northwestern University. The program was funded in January 1983, as the result of a national competition to establish an HSR&D field program in each of the VA regions. The goals of the Medical District 17 Field Program are to improve the health care of veterans by conducting relevant research on the processes and outcomes of patient care; to provide comprehensive technical research assistance; and to educate VA managers, planners, and clinicians, as well as the general medical community, about advances in health care delivery. The field program's commitment to excellence is strengthened by its multidisciplinary approach, which enables physicians, nurses, social workers, psychologists, sociologists, economists, statisticians, administrators, and individuals in various related disciplines to cooperate in efforts to address a wide range of topical issues. These collaborations are a major strength of the field program. Primary research priorities of the field program are cost effectiveness of VA services (e.g., patient care technologies, delivery systems), long-term care, and rehabilitation. Investigators, however, are not limited to these topics and explore many other health services research issues of particular interest to them.

Statistical methods in anesthesia articles: an evaluation of two American journals during two six-month periods

Simple criteria were used to evaluate the statistical analyses in 243 articles from two American anesthesia journals published in the latter six months of 1981 and 1983. Eighty-two percent of the articles reported the use of control measures and 37% reported randomization of treatment, where they were possible. Data were classified as nominal, ordinal, or interval; as independent or related samples; as two-sample or more-than-two-sample cases. The descriptive, inferential, and correlative tests used were evaluated for appropriate application and primary errors were identified. Nine percent of the 722 descriptive statistics had major errors, most of which were a description of ordinal data as though they were interval. The incidence of erroneous applications of 394 inferential statistical tests was 78%. Nearly three-quarters of the 308 primary inferential statistical errors involved either use of a test for independent samples on related data (and vice versa) or multiple applications of an uncorrected test to the same data. Only 4% of the 113 statistics of association were considered erroneous, most because the method was not identified. No differences were detected in the incidence of errors in either experimental design or statistical analysis across time or across the two anesthesia journals. Fifteen percent of the 243 articles in both journals at both times were without major errors in statistical analysis. Recognition of potential sources of error should make it easier for investigators to use experimental designs and statistical analyses appropriate to their needs.