Perioperative medication management: a case-based review of general principles

Medical consultants need to recommend the safest and the most effective ways to manage chronic medications in the perioperative period. Outcomes data from clinical trials are limited in regard to perioperative medication management, so specific clinical trials are not available to guide decision-making in most circumstances. More studies in this field are needed. Communication and collaboration with anesthesiologists and surgeons as well as with primary care physicians are key to achieving optimal outcomes.     

A systems approach to fluorescent immunoassay: general principles and representative applications.

We have developed an automated system for the immunoassay of subnanogram quantities of clinically interesting compounds by molecular fluorescence. The system includes all the necessary reagents and an automated fluorometer. The microprocessor-based instrument consists of a measurement and data-processing module and an automated sampling unit. With use of 10 pmol/L amounts of fluorescent dyes such as fluorescein, measurements with precision and accuracy of 1--3% are attained. In a competitive-binding fluorescence immunoassay, antigen labeled with a fluorescent dye competes with antigen in the sample or standard for a limited amount of antibody immobilized on a polyacrylamide bead 2--5 micrometers in diameter. After separating antibody-bound from free tracer, we measure the amount of fluorescence bound to the beads. In representative example assays, correlation of fluorescence immunoassay (y) with a reference radioimmunoassay (x) of thyroxine was y = 1.01x + 13 nmol/L, r = 0.98. Correlation of fluorescence immunoassay (y) with a reference radioimmunoassay (x) of triiodothyronine was y = 0.99x + 0.004 nmol/L, r = 0.96.     

Soft drug design: general principles and recent applications

Soft drug design represents a new approach aimed to design safer drugs with an increased therapeutic index by integrating metabolism considerations into the drug design process. Soft drugs are new therapeutic agents that undergo predictable metabolism to inactive metabolites after exerting their therapeutic effect. Hence, they are obtained by building into the molecule, in addition to the activity, the most desired way in which the molecule is to be deactivated and detoxified. In an attempt to systematize and summarize the related work done in a number of laboratories, including ours, the present review presents an overview of the general soft drug design principles and provides a variety of specific examples to illustrate the concepts. A number of already marketed drugs, such as esmolol, remifentanil, or loteprednol etabonate, resulted from the successful application of such design principles. Many other promising drug candidates are currently under investigation in a variety of fields including possible soft antimicrobials, anticholinergics, corticosteroids, beta-blockers, analgetics, ACE inhibitors, antiarrhythmics, and others. Whenever possible, pharmacokinetic and pharmacodynamic properties are briefly summarized and compared to those of other compounds used in the same field.     

Developing a poster for disseminating research findings.

One of the goals of research should be the dissemination of research findings. Presentation of research findings to an audience of interest can be accomplished through formal or informal presentations at professional conferences or on a departmental level, publication in a variety of professional journals, and presentation as a poster session. Poster presentations attract an audience of similar interest, permit interaction and clarification of the research process and findings by the researcher, allow creative expression in presentation, and help to build collegial relationships with others who hold similar interests. Posters are also a way for educators to present the research findings of others that answer specific clinical questions or provide a means of staff development. A well-designed poster gives the viewer a concise overview of the research problem/purpose, research methodology, sample, results, and implications. Since the less formal poster presentation is viewed as less intimidating to some researchers and conference participants, posters may provide a more relaxed atmosphere in which the exchange of information takes place.     

Multichannel intraluminal impedance: general principles and technical issues

Multichannel intraluminal impedance (MII) is a new technology that allows detection of bolus movement without the use of external radiation or radiolabeled substances. The principles of MII are based on changes in resistance to alternating electrical current (impedance) induced by the presence of various boluses within the esophagus. The timing of changes in multiple impedance-measuring segments in the esophagus allows determination of the direction of bolus movement. Combined MII and manometry (MII-EM) provides simultaneous information on intraesophageal pressures and bolus transit, offers the ability to monitor all types of reflux, and allows the detection of the physical (liquid, gas, or mixed) and chemical (acid, nonacid) characteristics of the gastroesophageal refluxate.     

Head injury instructions: a time to unify.

OBJECTIVE: To compare and contrast the head injury advice give by various hospitals in England after minor head injury, and to draw attention to the need for a national set of head injury instructions. METHODS: 50 accident and emergency departments were contacted by post and asked to supply a copy of their head injury information card or leaflet; 41 hospitals replied (82%). RESULTS: Comparison of the cards showed inconsistencies and conflicting advice given by the departments contacted. CONCLUSIONS: There is a need for a national head injury card and a proposal for such a card is presented.     

Intermittent auscultation of the fetal heart rate: a review of general principles

Multiple randomized clinical trials have been unsuccessful in providing evidence of efficacy of electronic fetal monitoring; thus, there is renewed interest in intermittent auscultation during labor for women with low-risk pregnancies. Auscultation must be used with palpation or external or internal electronic monitoring of uterine contractions. Auscultation and palpation require education, experience, and competency validation at regular intervals. Institutional policies and standards of care are mandatory for intermittent auscultation. Concerns exist regarding the personnel costs for auscultation; however, these costs may ultimately be shown to be offset by significant benefits in improved outcomes and patient satisfaction.     

Advances in prenatal screening for Down syndrome: I. general principles and second trimester testing

BACKGROUND: Down syndrome is one of the most important causes of mental retardation in the population. In the absence of prenatal screening and diagnosis, prevalence at birth in the United States would currently exceed 1:600. The purpose of prenatal screening is to identify those women at the increased risk for an affected pregnancy and to maximize the options available to these women. TESTS AVAILABLE: Second trimester serum screening involves combining the maternal age-specific risk for an affected pregnancy with the risks associated with the concentrations of maternal serum alpha-fetoprotein (MSAFP), unconjugated estriol (uE3), and human chorionic gonadotropin (hCG) (triple testing). A forth analyte, inhibin-A (INH-A), is increasingly being utilized (quadruple testing). Optimal second trimester screening requires the integration of a number of clinical variables, the most important of which is an accurate assessment of gestational age. In addition to Down syndrome, the triple and quadruple tests preferentially identify fetal trisomy 18, Turner syndrome, triploidy, trisomy 16 mosaicism, fetal death, Smith-Lemli-Opitz syndrome, and steroid sulfatase deficiency. Some programs modify the Down syndrome risks generated through maternal serum screening tests with fetal biometric data obtained by ultrasound. Other second trimester tests have shown promise, including the analysis of maternal urine and fetal cells in the maternal circulation, but none are in routine clinical use. CONCLUSION: The second trimester triple and quadruple tests provide benchmarks for evaluating new screening protocols. The combination of fetal biometry, new test development as well as clarification of the role of co-factors that affect the concentrations of analytes in existing tests should lead to greater efficacy in second trimester screening for Down syndrome.