Guiding Emergency Treatment With Extended Focused Assessment With Sonography in Trauma by Emergency Responders (GET eFASTER).

OBJECTIVE: Prehospital medicine has struggled to manage critical patients without the resources available to hospital-based teams. Point-of-care ultrasound could bridge this resource gap by providing critical insight into the pathology of trauma patients. This study aimed to determine if early positive extended focused assessment with sonography in trauma (eFAST) identification would lead to improved patient outcomes. METHODS: This is a prospective observational trial that took place from February 1, 2019, to August 13, 2021. Paramedics, with no prior ultrasound experience, at a single ground ambulance agency were trained in obtaining and interpretating eFAST examinations. RESULTS: Thirty-seven paramedics were trained and performed a total of 502 eFAST examinations with a total correct interpretation rate of 97.35%. There was a sensitivity of 30.0%/75.0%, specificity of 98.75%/94.05%, a positive predictive value of 33.33%/37.5%, a negative predictive value of 98.55%/98.75%, a positive likelihood ratio of 24.05/12.6, and a negative likelihood ratio of 0.71/0.27 for all exam/patient-only scans. The time spent on scene for eFAST and non-eFAST calls was not significantly different (F3, 2,512 = 2.59, P = .051, η2 = .003). CONCLUSION: Although we were able to show successful training and interpretation of eFAST with paramedics, given the low prevalence of disease, our study did not show eFAST use improving patient outcome. However, the large likelihood ratio suggests its benefit may lie with appropriate trauma resource utilization.

Thy1 associates with the cation channel subunit HCN4 in adult rat retina.

PURPOSE: The membrane expression and gene promoter of the glycosylphosphatidylinositol (GPI)-anchored protein Thy1 have been widely used to examine the morphology and distribution of retinal ganglion cells in normal eyes and disease models. However, it is not known how adult mammalian retinal neurons use Thy1. Because Thy1 is not a membrane-spanning protein and, instead, complexes with structural and signaling proteins in other tissues, the aim of this study was to find protein partners of retinal Thy1. METHODS: Coimmunoprecipitation, immunohistochemistry, confocal imaging, and patch-clamp recording were used to test for association of Thy1 and HCN4, a cation channel subunit, in adult rat retina. RESULTS: Hyperpolarization of cells immunopanned by an anti-Thy1 antibody activated HCN channels. Confocal imaging showed that individual somata in the ganglion cell layer bound antibodies against Thy1 and HCN4, that the majority of these bindings colocalized, and that some of the immunopositive cells also bound antibody against a ganglion cell marker (Brn3a). Consistent with these results, Thy1 and HCN4 were coimmunoprecipitated by magnetic beads coated with either anti-Thy1 antibody or anti-HCN4 antibody. In control experiments, beads coated with these antibodies did not immunoprecipitate a photoreceptor rim protein (ABCR) and uncoated beads did not immunoprecipitate either Thy1 or HCN4. CONCLUSIONS: This is the first report that Thy1 colocalizes and coimmunoprecipitates with a membrane-spanning protein in retina, that Thy1 complexes with an ion channel protein in any tissue, and that a GPI-anchored protein associates with an HCN channel subunit protein.