Prospective Comparison of Ultrasound-Guided Versus Palpation Techniques for Arterial Line Placement by Residents in a Teaching Institution

Background: Arterial line insertion is traditionally done by blind palpation. Residents may need multiple attempts for successful insertion, leading to longer procedure times and many failed attempts. Objective: We hypothesized that ultrasound guidance (USG) would be faster and more successful than traditional blind palpation (TBP) for radial artery line placement by residents. Methods: Patients undergoing elective surgery requiring a radial arterial line were randomized to either the USG or TBP groups. Exclusion criteria included a need for arterial line placement in an awake patient, emergent surgery, or American Society of Anesthesiologists (ASA) physical status class VI. After the induction of anesthesia, a postgraduate year 3 (PGY-3) or PGY-4 anesthesia resident placed an arterial line by either USG or TBP. Results: A total of 412 patients and 85 of 106 residents (80%) in the training program were included. The 2 groups were similar with respect to sex, weight, height, ASA class, baseline systolic blood pressure, and baseline heart rate. USG was faster than TBP (mean times 171.1 ± 16.7 seconds versus 243.6 ± 23.5 seconds, P = .012), required fewer attempts (mean 1.78 ± 0.11 versus 2.48 ± 0.15, P = .035), and had an improved success rate (96% versus 90%, P = .012). Conclusions: We found that residents using USG in an academic institution resulted in significantly faster placement of the arterial lines, fewer attempts, and fewer catheters used

The Liquid Argon in A Testbeam (LArIAT) experiment

The LArIAT liquid argon time projection chamber, placed in a tertiary beam of charged particles at the Fermilab Test Beam Facility, has collected large samples of pions, muons, electrons, protons, and kaons in the momentum range 0∼30-0140 MeV/c. This paper describes the main aspects of the detector and beamline, and also reports on calibrations performed for the detector and beamline components

Dark Matter Search in a Proton Beam Dump with MiniBooNE

6 pages, 7 figures6 pages, 7 figure

Measurement of the (π−\pi^-, Ar) total hadronic cross section at the LArIAT experiment

We present the first measurement of the negative pion total hadronic cross section on argon, which we performed at the Liquid Argon In A Testbeam (LArIAT) experiment. All hadronic reaction channels, as well as hadronic elastic interactions with scattering angle greater than 5~degrees are included. The pions have a kinetic energies in the range 100-700~MeV and are produced by a beam of charged particles impinging on a solid target at the Fermilab Test Beam Facility. LArIAT employs a 0.24~ton active mass Liquid Argon Time Projection Chamber (LArTPC) to measure the pion hadronic interactions. For this measurement, LArIAT has developed the ``thin slice method", a new technique to measure cross sections with LArTPCs. While generally higher than the prediction, our measurement of the ($\pi^-$,Ar) total hadronic cross section is in agreement with the prediction of the Geant4 model when considering a model uncertainty of $\sim$5.1\%.Comment: 15 pages, 15 figures, 3 tables, accepted by PR

The Liquid Argon In A Testbeam (LArIAT) Experiment

The LArIAT liquid argon time projection chamber, placed in a tertiary beam of charged particles at the Fermilab Test Beam Facility, has collected large samples of pions, muons, electrons, protons, and kaons in the momentum range 300-1400 MeV/c. This paper describes the main aspects of the detector and beamline, and also reports on calibrations performed for the detector and beamline components

Dark matter search in nucleon, pion, and electron channels from a proton beam dump with MiniBooNE

A search for sub-GeV dark matter produced from collisions of the Fermilab 8 GeV Booster protons with a steel beam dump was performed by the MiniBooNE-DM Collaboration using data from $1.86 \times 10^{20}$ protons on target in a dedicated run. The MiniBooNE detector, consisting of 818 tons of mineral oil and located 490 meters downstream of the beam dump, is sensitive to a variety of dark matter initiated scattering reactions. Three dark matter interactions are considered for this analysis: elastic scattering off nucleons, inelastic neutral pion production, and elastic scattering off electrons. Multiple data sets were used to constrain flux and systematic errors, and time-of-flight information was employed to increase sensitivity to higher dark matter masses. No excess from the background predictions was observed, and 90$\%$ confidence level limits were set on the vector portal and leptophobic dark matter models. New parameter space is excluded in the vector portal dark matter model with a dark matter mass between 5 and 50$\,\mathrm{MeV}\,c^{-2}$. The reduced neutrino flux allowed to test if the MiniBooNE neutrino excess scales with the production of neutrinos. No excess of neutrino oscillation events were measured ruling out models that scale solely by number of protons on target independent of beam configuration at 4.6$\sigma$.Comment: 19 pages, 25 figures, Data release: http://www-boone.fnal.gov/for_physicists/data_release/dark_matter_prd/ v2 Updated to published versio

The ecloud measurement setup in the Main Injector

Ecloud has been observed in many high intensity accelerators which can limit the amount of current that can be stored in them. In particular, for ProjectX, the amount of beam current that will be stored in the MI (Main Injector) will be {approx}160 x 10{sup 12} protons while the present maximum intensity is {approx}45 x 10{sup 12} protons which is about 3.5x less beam. Although ecloud has been observed in the MI, it has not caused instabilities at the present running conditions. However, there is no guarantee that instabilities caused by ecloud will not be a problem at ProjectX intensities. Therefore, a program has been started to study the ecloud effects with both computer simulations and experiments. In this paper, we will be focusing our attention on how coatings can affect the production of secondary electrons. We have installed an ecloud measurement setup in a straight section of MI which consists of one coated and one uncoated beam pipe with the same physical dimensions and at the same location, together with four retarding field analyzers (RFAs) and three sets of beam position monitors (BPMs) which can be used for the microwave measurements. An ecloud measurement setup was installed in a straight section of the Main Injector in 2009. The goal of the setup was to compare the characteristics of different beam pipe coatings when subjected to proton beam. The setup consists of one coated and one uncoated beam pipe with the same physical dimensions installed at the same location. Four RFAs (retarding field analyzers) and three BPMs (beam position monitors) used for microwave measurements have been used to measure the ecloud densities. The RFAs have performed very well and have collected both the time evolution and energy distribution of the ecloud for bare and two types of beam pipe coatings

Randomized Prospective Study Evaluating Single-Injection Paravertebral Block, Paravertebral Catheter, and Thoracic Epidural Catheter for Postoperative Regional Analgesia After Video-Assisted Thoracoscopic Surgery

Objective Video-assisted thoracoscopic surgery (VATS) has improved patient outcomes; however, postoperative pain remains potentially severe. The objective of this study was to compare adjunct analgesic modalities for VATS, including paravertebral nerve blockade (PVB) and thoracic epidural anesthesia (TEA). Design Prospective, randomized trial. Setting Large academic hospital, single institution. Participants Adult patients undergoing VATS. Interventions Ultrasound-guided PVB catheter, ultrasound-guided single-injection PVB, or TEA. Measurements and Main Results Postoperative visual analog scale pain scores (at rest and with knee flexion) and opioid usage were recorded. Pain scores (with movement) for the TEA group were lower than those for either PVB group at 24 hours (p ≤ 0.008) and for the PVB catheter group at 48 hours (p = 0.002). Opioid use in TEA group was lower than that for either PVB group at 24 and 48 hours (p < 0.001) and 72 hours (p < 0.05). Single-injection PVB was faster compared with PVB catheter placement (6 min v 12 min; p < 0.001) but similar to TEA (5 min). Patient satisfaction, nausea, sedation, and 6-month postsurgical pain did not differ between groups. Conclusions TEA led to lower pain scores and opioid requirement for VATS procedures compared with PVB techniques. Single-injection PVB was faster and equally as effective as PVB catheter, and it led to similar patient satisfaction as TEA; therefore, it should be considered in patients who are not ideal candidates for TEA