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Compensation neurosis is a severe and distressing condition to the individual. Its ramifications are complex and costly, involving often the family, the employer, other road users, the medical profession, the legal profession, trade union representation and society as a whole.
Rate/duration-specified drug delivery systems have recently begun to appear as pharmaceuticals and as research tools. In both therapeutics and research, their major advantage is prevention of transient peaking of blood or tissue concentrations that are side-effect producing and potentially toxic; these peaks are the rule with conventional drench- or pulse-modes of drug administration via ordinary dosage forms. Each drug's pharmacokinetics provides the basis for specifying the rates at which its controlled delivery dosage forms should function in vivo. That is what pharmacokinetics can do for controlled drug delivery systems. What the availability of controlled drug delivery systems can do for pharmacokinetics is to make it both convenient and economical to study the steady-state pharmacokinetic behavior of a drug during chronic administration--as opposed to the much more complex and costly procedure of studying the transient pharmacokinetic behavior of the drug. Moreover, achieving and maintaining an approximately steady-state simplifies the study of spatial gradients in drug concentration in body fluids and tissues. In this fashion, advances in the technology of dosage forms, and the conversion from their static specification only by quantity to a dynamic specification by rate/duration, are strongly interdependent with both the theory and practice of pharmacokinetics.
A new liquid chromatograph/mass spectrometer has been developed in our laboratory for application to analysis of biological molecules of extremely low volatility. Oxyhydrogen flames rapidly vaporize the total liquid-chromatographic effluent, and molecular and particle beam techniques are used to efficiently transfer the sample to the ionization source of the mass spectrometer. This new instrument is comparable in cost and complexity to a combined gas chromatograph/mass spectrometer, but extends the capabilities of combined chromatography/mass spectrometry to a broad range of compounds not previously accessible. We are currently testing biologically significant samples with this instrument, using reversed-phase liquid-chromatographic separation and both positive and negative ion chemical-ionization mass spectrometry. Results have been obtained from mixtures of nucleic acid components--bases, nucleosides, and nucleotides--and from amino acids, peptides, saccharides, fatty acids, vitamins, and antibiotics. In all cases investigated to date, ions indicative of molecular mass are obtained in at least one of the operating modes available. Detection limits are typically in the 1-10 ng range for full mass scans (about 80-600 amu); sub-nanogram quantities are usually detectable with single-ion monitoring.
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Several tests are currently available to assist in the diagnosis of the hepatitis C virus. These tests can be classified as antibody tests (ELISA, RIBA, and MATRIX-HCV) or tests that actually detect or quantify the hepatitis C virus (PCR techniques). These tests vary in cost, technical complexity, specimen handling requirements, and diagnostic information achieved. Those tests currently available to the clinician are reviewed along with their associated benefits and disadvantages.
Clinical microbiologists and hospital epidemiologists have traditionally been concerned with the isolation and identification of organisms for diagnosis in individual patients, and the detection of transmission of such organisms from patient to patient. The use of molecular biology techniques, such as nucleic acid probing and amplification, provides the potential for revolutionizing how we diagnose infecting pathogens and determining the relation between nosocomial isolates. In clinical microbiology, this means that we will be able to detect smaller amounts of DNA or RNA of pathogens than is currently possible, that the time required to identify and determine the antimicrobial susceptibility of slow-growing pathogens will be dramatically reduced, and that the diagnosis of nonculturable organisms will become possible. In hospital epidemiology, the use of such techniques has already provided tests with exceptional discriminatory power. Molecular techniques allow more efficient typing of all pathogens, and permit discrimination between strains of organisms that were previously phenotypically identical or uncharacterizable. Currently, cost and complexity limit the applicability of these techniques; however, they are likely to be developed for routine laboratory use in the next decade, and their impact will be considerable.
The term New Medicine describes our new age of health-care reform and biotechnological discoveries. While offering hope for a healthier and more productive nation, New Medicine challenges us to come to terms with the cost, the complex social issues resulting from medical breakthroughs, and the limits to autonomy. A simplified ABC overview of some of the many bioethical dilemmas that now confront us are offered in this article.
To monitor disease burden and trends associated with congenital syphilis (CS), effective prevention programs require a surveillance system that identifies CS cases in an accurate and timely manner. Before 1988, comprehensive CS surveillance was difficult for health departments to conduct because documentation of infection in infants required complex and costly long-term follow-up for up to 1 year after delivery; follow-up often was incomplete, and many infected infants were not identified. To estimate the public health burden of CS more accurately and eliminate long-term follow-up of infants by health department personnel, in 1988 CDC implemented a new CS case definition (1). Rather than relying on documentation of infection in the infant, the new case definition presumes that an infant is infected if it cannot be proven that an infected mother was adequately treated for syphilis before or during pregnancy (2). During 1993-1994, the Sexually Transmitted Disease Prevention and Control Program of the New Jersey Department of Health (NJDOH) evaluated its CS surveillance system to assess the accuracy and completeness of reporting using the new case definition and to determine the personnel costs associated with identifying and classifying CS cases. This report summarizes the results of the evaluation.
Health care in the '90s is more complex and costly than ever before, and the healthcare consumer is knowledgeable and discriminating. Critical care nurses, who have always been responsive to technological change, must now be more responsive to consumer needs. This requires a change in mindset and a commitment to satisfying the "healthcare consumer". This article identifies nursing's customers, defines customer service and details a five-step plan for building an intensive customer unit. A successful customer service program in the intensive care unit leads to economic stability for both unit and institution, to humanistic integrity and to professional advancement for nurses.
To adequately assess the viability of any particular causal theory of orthostatic intolerance, physical and physiological parameters thought to be associated with orthostasis must be evaluated simultaneously within the same individual. Time, cost, and complexity of instrumentation generally limit studies of orthostatic intolerance to a single independent effect for any given sample of subjects. We, therefore, measured 6 key physical and physiological variables associated with various theories of orthostatic intolerance in 14 males to test the hypothesis that physical factors rather than physiological reflex mechanisms were dominant in contributing to orthostatic tolerance. Measurements included height, plasma volume (expressed as percent of total weight), variation in R-R interval, leg compliance, and carotid-cardiac (high pressure), and cardiopulmonary (low pressure) baroreflex sensitivity. Subjects' orthostatic intolerance was quantified by time to syncope during progressive supine lower body decompression. Correlations, regression coefficients, and indices of replicability were calculated using 500 to 1,000 bootstrap resamplings of the original 14 observations. Although all six measurements correlated with time to syncope when evaluated individually, only height (negative), percent plasma volume weight (positive), and, to a lesser extent, carotid-cardiac baroreflex sensitivity yielded consistent (reproducible) results when all measures were tested simultaneously. These results suggest that while orthostatic intolerance may be dependent upon a variety of physiological reflexes, physical factors such as height and plasma volume tend to dominate the prediction of time to syncope during lower body negative pressure (LBNP). Physiological reflexes, which act to maintain adequate profusion to the brain during normal terrestrial posture in humans, may be overwhelmed by the additional orthostatic challenge imposed by progressive lower body decompression.
While TRUS is not of value as a screening tool, it is of considerable value in the early detection of cancer of the prostate in men with abnormal DRE and/or PSA. TRUS enables calculation of PSA density to identify men at low risk, thus eliminating many unnecessary biopsies. This results in favorable impact on both cost and morbidity. When biopsy is necessary, TRUS greatly enhances accuracy. Its role in staging is of less importance but can be useful when positive, and it adds little to the cost or complexity of the examination.
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Positron emission tomography (PET) is a new nuclear medicine technique. The number of PET facilities is limited due to the high costs and complexity of this diagnostic modality. The principles of PET are explained. The technique can be used to visualize and analyse tumor metabolism. Present applications include tumor detection, staging, determination of growth rate, malignancy grade and hormone receptor status.
Nutrition support in acute, chronic, or home care settings can be implemented successfully by the well-informed primary care physician, who often is the first to identify poor nutritional health in his or her patients. Using established protocols for the identification or of risk factors and indicators of malnutrition, specific alerts to the need for nutrition support are presented. The logical approach to nutrition support interventions through four stages representing the gradual increase in complexity and cost, paralleling the progressive inability to use regular foods and the gastrointestinal tract are discussed. Specific, practical measures that can be recommended and implemented by the primary care physician managing the older person are presented. The ethical, legal, and home health aspects of nutrition support in the care of the older American by the primary care physician are also reviewed.
The goals of radiologic imaging in the study of tumors can be summarized as follows: 1) Definition of the exact volume and site of the lesion; 2) Tumor differentiation from surrounding structures; 3) Possible definition of tumor nature; 4) Follow-up. The radiologic imaging modalities to be considered are: a) conventional radiography; b) angiography; c) US; d) CT; e) MR. Of the above techniques, MR imaging can be considered as adequate to differentiate benign from malignant masses. Moreover, MR provides detailed information on both lesion and surrounding structure and allows histopathologic diagnosis. Finally, it is superior to CT with i.v. contrast medium in recognizing small lesions. Thus, dynamic MR imaging with paramagnetic contrast medium is currently considered the method of choice in evaluating recurrences and differentiating the latter from recent fibroses. MR limitations include the small number of units, their complexity and cost and exam duration.
Single-needle (SN) dialysis employs tidal blood flow at the point of vascular access. The simplest SN systems convert this tidal flow to a pulsatile flow in the dialyser. It has been assumed that constant flow through the dialyser is necessary for optimal efficiency. Therefore SN blood circuits are designed to smooth the pulsatile flow in the dialyser to a relatively constant flow. This increase the complexity and cost of the SN system. In order to test the hypothesis that pulsatile flow results in lower clearances than constant flow, we performed measurements of clearance in vitro using pulsatile blood flow at time-averaged rates of 50-250 ml/min and tidal volumes 200-100 ml/min. These were compared with clearances using constant blood flow at the same rates. At all flow rates and at tidal volumes up to 50 ml, the clearance measurements obtained during pulsatile flow were identical to those obtained during constant flow.
The four mechanical valve prostheses currently available on the U.S. market have evolved from a field of more than 50 valves produced for human implantation since the early 1950s (Tables 11-1 to 11-4). This literature establishes that good results can be achieved with a number of cardiac prostheses if properly used and monitored after implant. The current generation of valves have demonstrated ease of implantation, improved durability, good hemodynamic performance, and reduced thromboembolism and thrombosis with proper anticoagulation. The cost and complexity of completing PMA by the FDA, concern over product liability, and patent rights on design and raw materials have narrowed the choice of devices for surgeons in the United States and slowed the pace of new market entries. The evolution of mechanical valves has been reviewed and modes of valve failure reviewed when pertinent. Clinical expectations for earlier generation devices and present valves also are reviewed. Prostheses under evaluation are discussed along with considerations for valve implantation, surveillance, and anticoagulation. We have employed the SJM valve since about 1985. The proven good hemodynamic performance in small sizes and low profile have made its application well suited to the pediatric population and for smaller aortic roots. The well-guarded hinge mechanism and low probability for disc entrapment have facilitated its use in chordal sparing mitral replacements in our experience. Application in the tricuspid position also has been successful but requires close attention to anticoagulation.
OBJECTIVES: A comparison was made of two methods of data collection used in a quality-assurance study to determine whether the study samples were comparable and self-reported satisfaction similarly. We also investigated whether patients who dropped out of treatment early were more dissatisfied than those who remained for more treatments. STUDY DESIGN: A comparison was made of data collected through self-administered, structured questionnaires in the two studies. Participants were invited consecutively by chiropractors in study 1; chiropractic patients, selected randomly from a reimbursement register, received a postal questionnaire in study 2. PARTICIPANTS: Study 1 aimed for a maximum of 20 patients for each of 31 chiropractors included under a reimbursement scheme in the county of Stockholm, Sweden. Six hundred and sixteen patients entered the study, and 83% participated in a survey conducted at their third visit. Three hundred patients were invited to respond to the postal questionnaire at least 1 month after they received chiropractic care; the response rate was 77%. MAIN OUTCOME MEASURES: Sociodemographic factors, area of complaint, sick-leave, perceived improvement, unpleasant side-effects and overall satisfaction with care. RESULTS: There were no differences noted between the two study groups, and patients who received fewer than three treatments were no less satisfied than those who received more. Additional analyses indicate that factors other than dissatisfaction influence whether patients remain in therapy for fewer than three visits. CONCLUSION: Quality-assurance studies conducted in the chiropractor's practice, using consecutive sampling and anonymous questionnaires, seem to give results that are similar to the more complex and costly method of obtaining randomly selected study subjects from a central source and collecting the information through anonymous postal surveys.