Evidentiary and theoretical foundations for virtual simulation in nursing education.

Virtual simulation has been used extensively in nursing education since the beginning of the COVID-19 pandemic due to the unavailability of clinical sites. Extant research supports substitution of up to 50% of nursing clinical hours with simulation. However, in many nursing programs virtual simulation is currently substituting more than half of traditional clinical hours, and the knowledge gaps and limitations surrounding virtual simulation exist. The purpose of this paper is to describe the evidentiary and theoretical foundations for virtual simulation. Through examination of adult learning theories, learning styles and Bloom's Revised Taxonomy, recommendations for maximizing the use of virtual simulation in the current clinical learning environment are outlined. Debriefing is a vital component of virtual simulation. Synchronous debriefing with nursing students, faculty, preceptors, and peers provides the opportunity for scaffolding to support students' learning needs and foster reflection and evaluation to mitigate shortcomings of virtual simulation in the current clinical learning environment.

Segmental cervical spine motion during orotracheal intubation of the intact and injured spine with and without external stabilization.

OBJECT: The purpose of this study was to establish a cadaveric model for evaluating cervical spine motion in both the intact and injured states and to examine the efficacy of commonly used stabilization techniques in limiting that motion. METHODS: Intubation was performed in fresh human cadavers with intact cervical spines, following the creation of a C4-5 posterior ligamentous injury. Movement of the cervical spine during direct laryngoscopy and intubation was recorded using video fluoroscopy and examined under the following conditions: 1) without external stabilization; 2) with manual in-line cervical immobilization; and 3) with Gardner-Wells traction. Subsequently, segmental motion of the occiput through C-5 (Oc-C5) was measured from digitized frames of the recorded video fluoroscopy. The predominant motion, at all levels measured in the intact spine, was extension. The greatest degree of motion occurred at the atlantooccipital (Oc-C1) junction, followed by the C1-2 junction, with progressively less motion at each more caudal level. After posterior destabilization was induced, the predominant direction of motion at C4-5 changed from extension to flexion, but the degree of motion remained among the least of all levels measured. Traction limited but did not prevent motion at the Oc-C1 junction, but neither traction nor immobilization limited motion at the destabilized C4-5 level. CONCLUSIONS: Cadaveric cervical spine motion accurately reflected previously reported motion in living, anesthetized patients. Traction was the most effective method of reducing motion at the occipitocervical junction, but none of the interventions significantly reduced movement at the subaxial site of injury. These findings should be considered when treating injured patients requiring orotracheal intubation.

Influence of adhesion molecule expression by human brain microvessel endothelium on cancer cell adhesion.

Cultures of endothelial (En) cells derived from human brain microvessels were established in order to characterize adhesion molecule expression and to assay the adhesion properties of neoplastic cell lines to monolayers of En cells. Low constitutive expression of beta1 integrin (CD29), and ICAM-2 (CD102) was detected on human brain microvessel En cells. The beta1 chain of the VLA integrin family, ICAM-1, E-selectin (CD62E) and VCAM-1 (CD106) but not ICAM-2 and PECAM-1 (CD31) expression was upregulated by IL1-alpha, and TNF-alpha proinflammatory cytokines. High expression of PECAM-1 was found on non-activated human brain EN cells. In order to study the potential role of adhesion molecules in neoplastic cell adhesion two tumor cell lines were chosen. Adhesion of a cell line (DU145) derived from a cerebral metastasis of prostate carcinoma to human brain microvessel En cell monolayers was less pronounced compared to adhesion of a primary prostate carcinoma cell line (ND1). Adhesion of cerebral metastatic neoplastic cell line (DU145) was not significantly influenced by incubation of endothelial cells with different proinflammatory cytokines. The adhesion capability of primary prostate carcinoma line (NDI) was significantly upregulated by TNF-alpha proinflammatory cytokine. Furthermore, the adhesion of ND1 was partly inhibited using anti-E-selectin and VCAM-1 monoclonal antibodies. There was no significant effect of anti-adhesion antibodies on the adhesion characteristics of the cerebral metastatic (DU145) cell line. Our data demonstrate that different mechanisms are involved in the adhesion of neoplastic cells to cerebral En cells and turn our attention to the importance of adhesion molecule expression in the formation of metastases.

The use of diagnostic ultrasound in evaluation of the abdomen in primates with emphasis on the rhesus monkey (Macaca mulatta).

To characterize the sonographic appearance of the abdominal organs in primates, a program of routine imaging and diagnostic evaluation was undertaken. Compound B-mode methodology with bistable and grey scale machines was employed utilizing a 2.25- to 3.5-MHZ transducer focused at 7 cm. Visualization of the liver, gallbladder, spleen, kidney and of intraabdominal pathology are described. The stage, position, and condition of a pregnancy can be determined by this methodology.

The use of Ringer's lactate in the treatment of children with cholera and acute noncholera diarrhoea.

Two regimens of fluid and electrolyte therapy were studied in children with severe cholera and noncholera diarrhoea. In one, lactated Ringer's solution was the sole intravenous fluid, additional water, glucose, and potassium being given by mouth. In the other, three different intravenous solutions were employed to meet all fluid and electrolyte requirements. The response to therapy was satisfactory with each regimen. Because of prolonged stupor or vomiting about 15% of children treated by the first regimen were unable to ingest a sufficient quantity of glucose solution by mouth, and intravenous supplementation with a hypotonic glucose-saline solution was necessary. It is concluded that lactated Ringer's solution is suitable as the sole intravenous solution for children with acute cholera and noncholera diarrhoea provided oral supplementation, as described, is possible. The study also provides useful observations on the means of evaluating fluid requirements in such children and specific guidelines for such therapy.

Comparison of Fluorescent Antibody with Cultural Technique for Isolation of Enteropathogenic Escherichia coli from Swine.

In an investigation of hogs as possible reservoirs of human strains of enteropathogenic Escherichia coli (EEC), 92 six-month-old grain- and garbage-fed hogs were examined on the farm and again at the packing plant. Of the 331 specimens obtained by swabbing the rectum, cecum, and edible meat carcass of these hogs, 125 were presumptively positive for EEC when screened by the fluorescent-antibody (FA) technique. These "presumptive positive" specimens then underwent extensive bacteriological examination and complete serological typing. The FA technique proved to be an easier, simpler, and more economical procedure than culture when a large number of specimens were examined for possible EEC serogroups. It was found especially valuable for identification of multiple serogroups of EEC within a single specimen. It also appeared to be more sensitive than cultural examination, since results were not dependent on the presence of large numbers of organisms in the specimen, or even on their viability. However, the FA technique was found to be less specific than culture because of cross-reactivity with antigenically related Enterobacteriaceae when fluorescein-labeled antisera were used. Therefore, any specimen found positive on FA examination should be considered as presumptive positive until confirmed by bacteriological examination and complete serological study.