A Realistic, Low-Cost Simulated Automated Chest Compression Device.

Audience: This simulated automated chest compression device was designed for use in simulation cardiac arrest cases involving emergency medicine residents, but it would be applicable to other learners such as nurses, pharmacists, and medical students. Background: Automated chest compression devices (ACCD) are commonly utilized in cardiac arrest in the emergency department and by emergency medical services (EMS) as patients arrive in the ED.1 Prolonged simulated cardiac arrest can be challenging to maintain proper chest compression depth and technique.2 Resident learning may be enhanced during cardiac arrest in the simulation environment by implementing the use of a simulated ACCD. Educational Objectives: By the end of this educational session using a resuscitation trainer or high-fidelity manikin, learners should be able to:Recognize appropriate application of simulated ACCD to an ongoing resuscitation caseDemonstrate proper positioning of simulated ACCD in manikin modelIntegrate simulated ACCD to provide compressions appropriately throughout cardiac arrest scenario. Educational Methods: We developed a cost-effective simulated ACCD for use in resuscitation simulation cases. An initial pilot session identified components of fidelity that were used to model the simulated ACCD after those utilized in clinical situations. Three simulated devices were created and then tested for efficacy during high-fidelity simulation with 25 emergency medicine residents. Research Methods: Visual analog scales were used to explore how the simulated ACCD affected perceived realism and stress level during the cardiac arrest simulation. Qualitative data were collected through open-ended learner feedback comments. The institutional review board at our institution reviewed this project and determined that it was exempt. Results: With inclusion of the simulated ACCD device, learners rated the simulation "more realistic" with an average rating of 74/100 and "less stressful" with an average rating of 69/100 on the visual analog scales. Learner comments noted that the use of the ACCD in simulation resulted in better resource availability and accurate environmental noise. Discussion: The simulated ACCD presented here was found to be effective, realistic, and practical for use by learners in a resuscitation curriculum. Our results suggest that implementating a cost-effective simulated ACCD ($98 for supplies) in high-fidelity simulation cardiac arrest cases enhances the perceived realism of the environment and offers physician learners a low-stress opportunity to practice the clinical application of ACCD in cardiac arrest resuscitation. Additionally, the use of the simulated ACCD, specifically in a prolonged resuscitation, eliminated the need for physically demanding manual chest compressions. Anecdotally, in simulated environments we have observed poor-quality manual chest compressions due to an understanding that the manikin is "not real," leading to decreased psychological fidelity from the shared acceptance of the poor-quality compressions. Thus, the presence of a simulated clinical device providing chest compressions could have increased the feel of realism through improved psychological fidelity. Additionally, we note that the physical and psychological fidelity of this simulated device was sufficient for physicians to perceive clinical implementation, but may be suboptimal for assistive staff, who are focused on the specific functionality and may benefit from training on the physical device in clinical use. Finally, our simulated ACCD resembles the clinical device our department uses; we advise modifications as appropriate to allow a simulated ACCD created for other learners to also resemble their clinically used ACCD. Topics: Automated chest compression device, ACLS, improvised equipment, high fidelity simulation.

Effects of ribavirin/sofosbuvir treatment and ITPA phenotype on endogenous purines.

Ribavirin (RBV), a purine analog, causes hemolytic anemia in some patients. In vitro, anemia appears to result from depletion of endogenous purines, but there are limited data in vivo. Single nucleotide polymorphisms in the gene encoding the inosine triphosphatase (ITPA) enzyme have been associated with protection against RBV-induced anemia and may mediate the effect of RBV treatment on endogenous purines. The purpose of this work was to determine the effect of RBV treatment on endogenous purine concentrations in individuals being treated for chronic hepatitis C virus (HCV) infection. Adenosine triphosphate (ATP), guanosine triphosphate (GTP), inosine triphosphate (ITP) and ribavirin triphosphate (RTP) were measured in whole blood obtained from 47 HCV-infected individuals at day zero (baseline), day three, day 28 and day 84 of RBV/sofosbuvir (SOF) treatment. ATP decreased -35.1% and -38.6% (p < 0.0001) at day 28 and day 84 of treatment, respectively compared to baseline. The decrease in ATP was greater in patients with ≤60% ITPA activity compared to those with 100% ITPA activity (-29.4% vs. -9.6%). GTP did not change during treatment but was 16.5% (p = 0.01) higher per 100 pmol/106 cells RTP in those with 100% ITPA activity. No significant change or effect of RTP or ITPA phenotype was noted for ITP. In summary, only ATP was reduced by RBV/SOF treatment and ITPA variants had larger reductions in ATP suggesting RBV-induced anemia is due to a different mechanism than predicted from in-vitro studies. These data emphasize the importance of characterizing the effect of nucleos(t)ide analog treatment on endogenous purines in-vivo.

Lateral acetabular labral length is inversely related to acetabular coverage as measured by lateral center edge angle of Wiberg.

Patients with developmental dysplasia of the hip often have compensatory labral hypertrophy, which presumably lends stability to an unstable joint. Conversely, patients with acetabular overcoverage may have small or ossified labra. The purpose of this study is to explore the interaction of labral length with the degree of acetabular hip coverage. A retrospective cohort of patients with hip pain presenting to a hip preservation center, who had undergone hip magnetic resonance imaging and AP pelvis radiographs were studied. General linear multivariate models were used to assess the association between three measures of labral length (lateral, anterior and anterior inferior locations along the acetabular rim) and the X-ray derived lateral center edge angle (LCEA) of Wiberg. Of the three acetabular labral locations measured, only the lateral labrum was associated with LCEA Wiberg (P = 0.0008). Lateral labral length increases as LCEA of Wiberg decreases. The anterior and anterior inferior labral locations did not show a predictable increase in labral length as LCEA Wiberg decreased.

Intracellular Tenofovir and Emtricitabine Anabolites in Genital, Rectal, and Blood Compartments from First Dose to Steady State.

The pharmacokinetics (PK) of tenofovir-diphosphate (TFV-DP) and emtricitabine-triphosphate (FTC-TP), the active anabolites of tenofovir disoproxil fumarate (TDF), and emtricitabine (FTC) in blood, genital, and rectal compartments was determined in HIV-positive and seronegative adults who undertook a 60-day intensive PK study of daily TDF/FTC (plus efavirenz in HIV positives). Lymphocyte cell sorting, genital, and rectal sampling occurred once per subject, at staggered visits. Among 19 HIV-positive (3 female) and 21 seronegative (10 female) adults, TFV-DP in peripheral blood mononuclear cells (PBMC) accumulated 8.6-fold [95% confidence interval (CI): 7.2-10] from first-dose to steady-state concentration (Css) versus 1.7-fold (95% CI: 1.5-1.9) for FTC-TP. Css was reached in ∼11 and 3 days, respectively. Css values were similar between HIV-negative and HIV-positive individuals. Css TFV-DP in rectal mononuclear cells (1,450 fmol/106 cells, 898-2,340) was achieved in 5 days and was >10 times higher than PBMC (95 fmol/106 cells, 85-106), seminal cells (22 fmol/106 cells, 6-79), and cervical cells (111 fmol/106 cells, 64-194). FTC-TP Css was highest in PBMC (5.7 pmol/106 cells, 5.2-6.1) and cervical cells (7 pmol/106 cells, 2-19) versus rectal (0.8 pmol/106 cells, 0.6-1.1) and seminal cells (0.3 pmol/106 cells, 0.2-0.5). Genital drug concentrations on days 1-7 overlapped with estimated Css, but accumulation characteristics were based on limited data. TFV-DP and FTC-TP in cell sorted samples were highest and achieved most rapidly in CD14+ compared with CD4+, CD8+, and CD19+ cells. Together, these findings demonstrate cell-type and tissue-dependent cellular pharmacology, preferential accumulation of TFV-DP in rectal mononuclear cells, and rapid distribution into rectal and genital compartments.