A Review of the Benefits and Pitfalls of Phantoms in Ultrasound-Guided Regional Anesthesia

Abstract: With the growth of ultrasound-guided regional anesthesia, so has the requirement for training tools to practice needle guidance skills and evaluate echogenic needles. Ethically, skills in ultrasound-guided needle placement should be gained in a phantom before performance of nerve blocks on patients in clinical practice. However, phantom technology is varied, and critical evaluation of the images is needed to understand their application to clinical use. Needle visibility depends on the echogenicity of the needle relative to the echogenicity of the tissue adjacent the needle. We demonstrate this point using images of echogenic and nonechogenic needles in 5 different phantoms at both shallow angles (20 degrees) and steep angles (45 degrees). The echogenicity of phantoms varies enormously, and this impacts on how needles are visualized

Tranexamic acid use in severely injured civilian patients and the effects on outcomes

Objective: To characterize the relationship between tranexamic acid (TXA) use and patient outcomes in a severely injured civilian cohort, and to determine any differential effect between patients who presented with and without shock. Background: TXA has demonstrated survival benefits in trauma patients in an international randomized control trial and the military setting. The uptake of TXA into civilian major hemorrhage protocols (MHPs) has been variable. The evidence gap in mature civilian trauma systems is limiting the widespread use of TXA and its potential benefits on survival. Methods: Prospective cohort study of severely injured adult patients (Injury severity score > 15) admitted to a civilian trauma system during the adoption phase of TXA into the hospital's MHP. Outcomes measured were mortality, multiple organ failure (MOF), venous thromboembolism, infection, stroke, ventilator-free days (VFD), and length of stay. Results: Patients receiving TXA (n = 160, 42%) were more severely injured, shocked, and coagulopathic on arrival. TXA was not independently associated with any change in outcome for either the overall or nonshocked cohorts. In multivariate analysis, TXA was independently associated with a reduction in MOF [odds ratio (OR) = 0.27, confidence interval (CI): 0.10-0.73, P = 0.01] and was protective for adjusted all-cause mortality (OR = 0.16 CI: 0.03-0.86, P = 0.03) in shocked patients. Conclusions: TXA as part of a major hemorrhage protocol within a mature civilian trauma system provides outcome benefits specifically for severely injured shocked patients

Tranexamic acid use in severely injured civilian patients and the effects on outcomes

Objective: To characterize the relationship between tranexamic acid (TXA) use and patient outcomes in a severely injured civilian cohort, and to determine any differential effect between patients who presented with and without shock. Background: TXA has demonstrated survival benefits in trauma patients in an international randomized control trial and the military setting. The uptake of TXA into civilian major hemorrhage protocols (MHPs) has been variable. The evidence gap in mature civilian trauma systems is limiting the widespread use of TXA and its potential benefits on survival. Methods: Prospective cohort study of severely injured adult patients (Injury severity score > 15) admitted to a civilian trauma system during the adoption phase of TXA into the hospital's MHP. Outcomes measured were mortality, multiple organ failure (MOF), venous thromboembolism, infection, stroke, ventilator-free days (VFD), and length of stay. Results: Patients receiving TXA (n = 160, 42%) were more severely injured, shocked, and coagulopathic on arrival. TXA was not independently associated with any change in outcome for either the overall or nonshocked cohorts. In multivariate analysis, TXA was independently associated with a reduction in MOF [odds ratio (OR) = 0.27, confidence interval (CI): 0.10-0.73, P = 0.01] and was protective for adjusted all-cause mortality (OR = 0.16 CI: 0.03-0.86, P = 0.03) in shocked patients. Conclusions: TXA as part of a major hemorrhage protocol within a mature civilian trauma system provides outcome benefits specifically for severely injured shocked patients

Rapidly Decaying Supernova 2010X: A Candidate ".Ia" Explosion

We present the discovery, photometric and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with tau_d=5 days, and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M_r=-17mag and has mean velocities of 10,000 km/s. Our light curve modeling suggests a radioactivity powered event and an ejecta mass of 0.16 Msun. If powered by Nickel, we show that the Nickel mass must be very small (0.02 Msun) and that the supernova quickly becomes optically thin to gamma-rays. Our spectral modeling suggests that SN 2010X and SN 2002bj have similar chemical compositions and that one of Aluminum or Helium is present. If Aluminum is present, we speculate that this may be an accretion induced collapse of an O-Ne-Mg white dwarf. If Helium is present, all observables of SN 2010X are consistent with being a thermonuclear Helium shell detonation on a white dwarf, a ".Ia" explosion. With the 1-day dynamic-cadence experiment on the Palomar Transient Factory, we expect to annually discover a few such events.Comment: 6 pages, 5 figures; Minor Changes; Note correction in Fig 4 caption; published by ApJ