Nurses' knowledge and attitudes about antibiotic therapy in critical care.

PURPOSE: To assess critical care nurses' knowledge about antibiotic use in critical care settings, and attitudes concerning the role of the nurse in monitoring response to and appropriate use of antibiotic therapy. METHOD: 90 critical care nurses from 6 adult critical care units at a 780-bed academic, health sciences centre, completed an investigator-developed survey about their knowledge of antibiotic use and their attitudes concerning the role of the nurse. RESULTS: The majority of respondents worked full time (83%) and were BSN (Bachelor of Science in Nursing) prepared (62%), with an average of 9 years' nursing experience and 7 years' experience in intensive care. Using a 100-mm visual analog scale, mean scores on knowledge and comfort with: (1) interpreting culture and sensitivity; (2) white blood cell (WBC) data; and (3) discussing results and therapy with physicians were all less than 50 mm. However, the mean score for nurses' belief of responsibility related to this collaborative role was 76. A knowledge quiz of lab interpretation and antibiotic therapy revealed a mean score of 53.8%. Beliefs about roles were correlated with comfort in discussing therapies with physicians rather than with knowledge. Although nurses value the collaborative surveillance role, they may lack the knowledge and confidence to enact it.

Continuous measurement of backrest elevation in critical care: a research strategy.

OBJECTIVE: To develop and test a procedure for continuous measurement of backrest elevation in critical care for enhancing the precision of this measurement for research purposes. DESIGN: Descriptive, correlational. SETTING AND MEASUREMENTS: Backrest elevation, defined as the height of the head of the bed in degrees of elevation above horizontal, can be continuously monitored by using two transducers, one attached to the bed frame just distal to the head of the bed gatch and another attached to the bed frame at the top of the bed. By monitoring the differential head pressure between the two pressure channels, the height of the head of the bed can be calculated. A total of 30 random measurements of backrest elevation, from 0 degrees to 60 degrees, were taken by using the backrest elevation measurement on the bed frame, a handheld protractor, and the pressure differential between two transducers attached to the bed frame. Data collectors recorded one measurement independent of the other measurements. All measurements were conducted on the same bed. RESULTS: When the transduced method was compared with measurements by using a protractor, the Bland-Altman analysis technique yielded upper and lower limits of agreement of 8.93 degrees and -5.91 degrees, respectively. The bias was 1.51 degrees, and the precision was 3.71 degreees. CONCLUSIONS: The measurement technique described here was developed for research purposes to add precision to research studies examining the appropriate height of the backrest. However, the procedure could be used in a continuous quality improvement process to enhance compliance with patient care procedures involving backrest elevation or to confirm actual nursing practice and its correlation with patient outcome. In light of the risks associated with the use of supine positioning in critically ill and mechanically ventilated patients, the information gained from continuous measurement of backrest position could be an extremely valuable research tool.

Genetic characterization of a Streptococcus mutans LraI family operon and role in virulence.

Proteins belonging to the LraI (for "lipoprotein receptor antigen") family function as adhesins in several streptococci, as a virulence factor for endocarditis in at least one of these species, and potentially as metal transporters in many bacteria. We have identified and characterized the chromosomal locus containing the LraI family gene (designated sloC) from Streptococcus mutans, an agent of dental caries and endocarditis in humans. Northern blot analysis indicated that sloC is cotranscribed with three other genes. As with other LraI operons, the sloA and sloB genes apparently encode components of an ATP-binding cassette transport system. The product of the fourth gene, sloR, has homology to the metal-dependent regulator from Corynebacterium diphtheriae, DtxR. A potential binding site for SloR was identified upstream from the sloABCR operon and was conserved upstream from LraI operons in several other streptococci. Potential SloR homologs were identified in the unfinished genomic sequences from two of these, S. pneumoniae and S. pyogenes. Mutagenesis of sloC in S. mutans resulted in apparent loss of expression of the entire operon as assessed by Northern blot analysis. The sloC mutant was indistinguishable from its wild-type parent in a gnotobiotic rat model of caries but was significantly less virulent in a rat model of endocarditis. Virulence for endocarditis was restored by correction of the sloC mutation but not by provision of the sloC gene in trans, suggesting that virulence requires the expression of other genes in the sloC operon.

Oral care in the adult intensive care unit.

BACKGROUND: Nurses have not been formally trained in assessing the oral status of patients in intensive care units, and no oral care protocols for these patients are available. OBJECTIVES: To assess the oral status of patients in an intensive care unit, evaluate the effects of a defined oral care protocol on the oral health status of patients in an intensive care unit, and compare oral assessments of a dental hygienist with those of intensive care nurses. METHODS: A nonequivalent comparison group, longitudinal design with repeated measures was used. In phase 1, oral assessment data on the comparison group were collected by a dental hygienist. In phase 2, nurses were instructed in oral assessment and an oral care protocol. In phase 3, the oral care protocol was implemented in the treatment group, and oral assessment data were collected separately by the dental hygienist and by nurses. RESULTS: The mean inflammation score was significantly lower (t test P = .03) in the treatment group (mean, 3.9; SEM, 3.0) than in the comparison group (mean, 12.4; SEM, 2.2). Although not significant, the mean scores of the treatment group were also lower than those of the comparison group on scales of candidiasis, purulence, bleeding, and plaque. Correlations between scores for individual items on the oral assessment tool obtained by the dental hygienist and those obtained by nurses were all greater than 0.6386. CONCLUSION: Implementation of a well-developed oral care protocol by bedside nurses can improve oral health of patients in the intensive care unit.

Implications for nursing of the Human Genome Project.

Information obtained from the Human Genome Project, initiated in 1990 and targeted for completion in 2005, will influence both health care and nursing practice. It will substantially revise our understanding of disease susceptibility and causation. Additional genetic tests will be developed and gene therapies explored. The project has implications for both nursing research and nursing practice. This article reviews the establishment of the Human Genome Project, reports on current progress of the project, and identifies some implications of the project for health care generally and nursing specifically.

Use of backrest elevation in critical care: a pilot study.

BACKGROUND: Use of lower backrest positions occurs frequently and is a factor in the development of ventilator-associated pneumonia. OBJECTIVES: To determine the usual bed elevation and backrest position in a medical intensive care unit and their relationship to hemodynamic status and enteral feeding. METHODS: Data were collected in a 12-bed medical respiratory intensive care unit for 2 months. A protractor was used to measure the elevation of the head of the bed. Hemodynamic status was defined by systolic, diastolic, and mean arterial blood pressure measurements retrieved from each patient's flow sheet. RESULTS: The sample included 347 measurements of 52 patients. Mean backrest elevation was 22.9 degrees, and 86% of patients were supine. Backrest position differed significantly (P = .005) among nursing shifts (days, evenings, nights) but not for systolic (r = -0.04, P = .49), diastolic (r = 0.01, P = .83), or mean arterial blood pressure (r = -0.01, P = .84). Backrest elevation did not differ significantly between patients who were receiving enteral feedings and patients who were not (P = .23) or between patients receiving intermittent versus continuous nutrition (P = .22). CONCLUSIONS: Use of higher levels of backrest elevation (> or = 30 degrees) is minimal and is not related to use of enteral feeding or to hemodynamic status. The rationale for using lower backrest positions for critically ill patients may be based on convenience, the patient's comfort, or usual patterns in the unit. However, the dangers of supine positioning and its relationship to aspiration and ventilator-associated pneumonia should not be minimized.

A comparison of two culturing methods for chronic wounds.

Bacterial infection has always been a potential complication of any wound. Controversy exists regarding the significance of bacteria in chronic wounds. It is important to accurately diagnose wound infection by bacterial identification and quantification in order to prevent unnecessary and/or inappropriate treatments and to minimize patient complications. The primary function of culturing is to identify infection in a wound. The tissue culture is an accepted standard for measuring infection, although swab cultures are commonplace in the clinical setting. The purpose of this study was to test the differences in bacterial counts and identification in swab and tissue cultures taken from the same wound site of 10 chronic wounds. It was hypothesized that if swab and tissue cultures are equally effective in identifying and quantifying the organisms in a chronic wound, they are equally effective methods in determining infection in the chronic wound. The reliability, validity and limitations of the study are discussed, as well as the statistical analyses and results.

Immunization with FimA protects against Streptococcus parasanguis endocarditis in rats.

FimA, a surface-associated protein of Streptococcus parasanguis, is associated with initial colonization of damaged heart tissue in an endocarditis model (D. Burnette-Curley, V. Wells, H. Viscount, C. Munro, J. Fenno, P. Fives-Taylor, and F. Macrina, Infect. Immun. 63:4669-4674, 1995). We have evaluated the efficacy of recombinant FimA as a vaccine in the rat model of endocarditis and investigated in vitro the mechanism for the protective role of immunization. FimA-immunized and nonimmunized control animals were catheterized to induce heart valve damage and infected intravenously with 10(7) CFU of wild-type S. parasanguis FW213 bacteria. The presence of bacteria associated with platelet-fibrin vegetations 24 h postchallenge was evaluated. Immunized rats were significantly less susceptible to endocarditis (2 cases among 34 animals) than the control group (21 cases among 33 animals) (P < 0.001). Incubation of S. parasanguis FW213 with rabbit anti-FimA immune serum decreased the mean percent adherence (0.34% of added cells) to platelet-fibrin matrix in vitro compared with that of preimmune normal serum (5.04% of added cells; P < 0.001). Adsorption of immune serum with FimA-positive S. parasanguis FW213 yielded antiserum that failed to block adherence to the platelet-fibrin matrix. We assessed the vaccine potential of FimA as a common immunogen able to provide cross-protection in streptococcal endocarditis by determining the occurrence and expression of fimA in the viridans group streptococci and enterococci. We detected the presence of fimA homologs by Southern hybridization and PCR amplification analyses and determined by immunoblotting the expression of FimA-like proteins among a variety of streptococci and enterococci that frequently cause endocarditis. Eighty-one percent (26 of 32) of streptococcal and enterococcal strains isolated from bacteremic patients expressed proteins that comigrated with FimA and were reactive with polyclonal anti-FimA serum. Streptococcal DNA from strains that were positive by Western blot (immunoblot) analysis hybridized to the full-length fimA probe. Our studies suggest that FimA immunization results in antibody-mediated inhibition of bacterial adherence, a critical early event in the pathogenesis of endocarditis. Our data demonstrate that a majority of streptococcal strains associated with endocarditis have genes that encode FimA-like proteins. Taken together, these results suggest that FimA is a promising candidate for an endocarditis vaccine.

Ventilator-associated pneumonia: clinical significance and implications for nursing.

Pneumonia is the second most common nosocomial infection in the United States and the leading cause of death from nosocomial infections. Intubation and mechanical ventilation greatly increase the risk of bacterial pneumonia. Ventilator-associated pneumonia (VAP) occurs in a patient treated with mechanical ventilation, and it is neither present nor developing at the time of intubation; it is a serious problem--with significant morbidity and mortality rates. Aspiration of bacteria from the oropharynx, leakage of contaminated secretions around the endotracheal tube, patient position, and cross-contamination from respiratory equipment and health care providers are important factors in the development of VAP. Nurses caring for patients treated with mechanical ventilation must recognize risk factors and include strategies for reducing these factors as part of their nursing care. This article summarizes the literature related to VAP: its incidence, associated factors, diagnosis, and current therapies, with an emphasis on nursing implications in the care of these patients.

Inherited disorders: a genetic primer.

Identification of inherited or genetic disorders has important implications for the prognosis and treatment of affected infants. This article addresses the three most common categories of genetic disorders--single-gene defects, chromosomal abnormalities, and multifactorial conditions. The principles of transmission, risk of inheritance, and clinical significance of each category are discussed, with examples of inherited disorders in each category.

The basis of heredity: a genetic primer.

Traits seen in the neonate are a direct result of the expression of genes donated by parents at the time of conception. This article discusses the configuration of genetic material in humans, explains how an individual's genetic composition is unique, and demonstrates the importance of genetic information in determining traits related to health, disease, and individuality.

Nursing management of adults who have cystic fibrosis.

Cystic fibrosis has ceased to be a terminal illness for children and has become a chronic disease affecting both children and adults. Life expectancy, already over 29 years, is increasing with new therapeutic interventions. Pathophysiology, assessment, and treatment information is presented here to assist adult health nurses in caring for patients with cystic fibrosis.

Immunologic characteristics of a Streptococcus mutans glucosyltransferase B sucrose-binding site peptide-cholera toxin B-subunit chimeric protein.

Glucosyltranferases (Gtfs) produced by the mutans streptococci are recognized as virulence factors in dental caries, and the inhibition of Gtfs by secretory immunoglobulin A is predicted to provide protection against this disease. The basis of such mucosal immunity is linked to the ability to reliably stimulate production of secretory immunoglobulin A against Gtfs. In this regard, we are exploring the immunogenicities of various Gtf peptides genetically fused to the B subunit of cholera toxin (CTB), a known mucosal adjuvant. In this work, we have created a gene fusion linking the GtfB active-site (AS) peptide DANFDSIRVDAVDNVDADLLQIA to the amino terminus of CTB. This sequence, deduced from the nucleotide sequence of gtfB from Streptococcus mutans GS5, has been found to be strongly conserved in Gtfs from several mutans streptococci. We have purified this recombinant protein (AS:CTB) from Escherichia coli carrying the fusion gene under the control of the lactose operon promoter. This protein was immunogenic in rabbits and produced specific serum antibodies against both the Gtf peptide and the CTB moiety. The antiserum was tested for its ability to inhibit GtfB activity obtained from a mutant of S. mutans able to make only this enzyme and none of the other usual Gtfs or fructosyltransferase. Approximately 50% of the GtfB activity was inhibited in such assays. These results suggest that the AS of this enzyme is accessible to antibody binding and that this region of the protein may be considered a vulnerable target for vaccine design and development. The AS:CTB was able to bind GM1, ganglioside in enzyme-linked immunosorbent assays, indicating that the recombinant protein retained this property, which is though to be critical to the mucosal immunoadjuvant properties of CTB. Thus, this protein may be promising as a candidate anticaries vaccinogen alone or in combination with other Gtf peptides or conjugates.

FimA, a major virulence factor associated with Streptococcus parasanguis endocarditis.

Adherence of microorganisms to damaged heart tissue is a crucial event in the pathogenesis of infective endocarditis. In the present study, we investigated the role of the FimA protein as a potential virulence factor associated with Streptococcus parasanguis endocarditis. FimA is a 36-kDa surface protein that is a recognized adhesin in the oral cavity where it mediates adherence to the salivary pellicle. An insertion mutant and a deletion mutant of S. parasanguis were employed in the rat model of endocarditis to determine the relevance of FimA in endocarditis pathogenesis. Catheterized rats were infected with either the fimA deletion mutant VT929, the fimA insertion mutant VT930, or the isogenic, wild-type S. parasanguis FW213. Rats inoculated with FW213 developed endocarditis more frequently (50.9%) than animals inoculated with either the deletion mutant (2.7%) or the insertion mutant (7.6%) (P < 0.001). A series of in vitro assays were performed to explore the mechanism(s) by which FimA enhanced the infectivity of S. parasanguis. FimA did not inhibit the uptake or the subsequent killing of S. parasanguis by phagocytic granulocytes. Similarly, FimA did not play a role in the adherence to or the aggregation of platelets. Significant differences were noted between FW213 and VT929 (P < 0.05) and FW213 and VT930 (P < 0.001) in their abilities to bind to fibrin monolayers. The mean percent adherence of FW213 to fibrin monolayers (2.1%) was greater than those of VT929 (0.5%) and VT930 (0.12%). Taken together, these results indicate that FimA is a major virulence determinant associated with S. parasanguis endocarditis and further suggest that its role is associated with initial colonization of damaged heart tissue.

The impact of recent advances in microbiology and immunology on perinatal and women's health care.

Microbiology and immunology have offered important advances in the care of women and newborns. Understanding of the interplay between individuals and the microorganisms associated with them has provided the framework for important changes in practice. An excellent historical example of this idea, well known to nurses, involves puerperal fever. A recent example is knowledge of the relationship of breastfeeding and human immunodeficiency virus. Recent advances in microbiology and immunology that have improved women's health include improved diagnostic tests and a more complete understanding of the vaginal biofilm.

Sucrose-derived exopolymers have site-dependent roles in Streptococcus mutans-promoted dental decay.

We have constructed a panel of mutants of S. mutans V403 which are defective in one or more of the glucosyltransferase genes (gtfB, C or D) or the fructosyltransferase gene (ftf). These strains have been tested for virulence in a gnotobiotic rat caries model with reference to both buccal (smooth surface) and sulcal (pit and fissure) carious lesions. Our data suggest differing roles for degradable and non-degradable polymers at buccal and sulcal sites. Non-degradable polymers (made by products of the gtfB and C genes) contributed significantly to the severity of smooth surface lesions. However, our studies suggested their role in pit and fissure lesions was not as important as the role of degradable polymers. Specifically, a mutant deficient in the major insoluble glucan synthesizing activity (product of the gtfB gene) was 25% more cariogenic on sulcal surfaces than was the wild-type V403 strain. We propose that extracellular glucosyltransferases and fructosyltransferase compete for sucrose and that this competition influences pathogenicity at differing tooth sites.

Gene therapy for inherited disorders.

With an increase in understanding of the role of genes in disease pathogenesis, gene therapy has become a reality for some disorders and an increased possibility for many others. One type of gene therapy requires only gene addition for treatment. Different methods for gene addition are being tested, based on the cell typology necessary to make the therapy effective. Gene therapy trials for patients with adenosine deaminase deficiency involve a retroviral approach. Gene therapy trials for patients with cystic fibrosis involve an adenoviral approach. This article describes the differences between these two methods of gene therapy. The application of this knowledge to pediatric nursing practice is discussed.

The case study approach to teaching scientific integrity in nursing and the biomedical sciences.

Scientific integrity courses for graduate trainees are emerging at many institutions. The content of such courses varies and is evolving as faculty strive to meet the needs of their specific student audiences. Typical course subject matters include responsible authorship, conflict of interest, handling of scientific misconduct, data management, and the use of humans and animals in biomedical experimentation. These and other topic areas are amenable to teaching methods that use the case study approach. In this article we discuss our experiences in teaching scientific integrity using the case study approach. Issues covered include underlying philosophy of the approach, preparation and use of cases, desired inclass preparation and teaching. Examples of short cases are presented and, where appropriate, discussed in the context of these issues.

Blastomere analysis: issues for discussion.

There has been little professional discussion about the implications of blastomere analysis for genetic screening. In this article, some of the legal, ethical, and practical issues associated with the technology are identified. Issues are categorized as those involving availability and payment, phenotype selection, and imperfect genes. Nurses need to be knowledgeable about these issues to participate in the formation of policies governing the use of blastomere analysis and other genetic screening procedures.