159,709 research outputs found
Mechanical chest-compression devices: current and future roles
Purpose of review: It is recognised that the quality of CPR is an important predictor of outcome from cardiac arrest yet studies consistently demonstrate that the quality of CPR performed in real life is frequently sub-optimal. Mechanical chest compression devices provide an alternative to manual CPR. This review will consider the evidence and current indications for the use of these devices.
Recent findings: Physiological and animal data suggest that mechanical chest compression devices are more effective than manual CPR. However there is no high quality evidence showing improved outcomes in humans. There are specific circumstances where it may not be possible to perform manual CPR effectively e.g. during ambulance transport to hospital, en-route to and during cardiac catheterisation, prior to organ donation and during diagnostic imaging where using these devices may be advantageous.
Summary: There is insufficient evidence to recommend the routine use of mechanical chest compression devices. There may be specific circumstances when CPR is difficult or impossible where mechanical devices may play an important role in maintaining circulation. There is an urgent need for definitive clinical and cost effectiveness trials to confirm or refute the place of mechanical chest compression devices during resuscitation
Strongly anharmonic current-phase relation in ballistic graphene Josephson junctions
Motivated by a recent experiment directly measuring the current-phase
relation (CPR) in graphene under the influence of a superconducting proximity
effect, we here study the temperature dependence of the CPR in ballistic
graphene SNS Josephson junctions within the the self-consistent tight-binding
Bogoliubov-de Gennes (BdG) formalism. By comparing these results with the
standard Dirac-BdG method, where rigid boundary conditions are assumed at the
SN interfaces, we show on a crucial importance of both proximity effect and
depairing by current for the CPR. The proximity effect grows with temperature
and reduces the skewness of the CPR towards the harmonic result. In short
junctions () current depairing is also important and gives rise to a
critical phase over a wide range of temperatures and doping
levels.Comment: 7 pages, 4 figures. v2 contains very minor change
CPR and ECC
This practical workshop will demonstrate the following Emergency and Critaickl Care techiques:
Cardioplumonary Resuscitation.
Thoracocentesis.
Intermittent Positive Pressure Ventilation.
Delegates will then be provided with the opportunity to practice the techniques themeselves on professional mannequins
A river basin as a common-pool resource: a case study for the Jaguaribe basin in Brazil
Rainfall variability and the associated water stress are of major concern in semi-arid regions subject to conflicts between water users. To achieve sustainable and stable agricultural performance it is necessary to understand\ud
the interaction between natural processes and human response. This paper investigates the applicability of common-pool resource (CPR) concepts to understand governance of water resources in semi-arid river basins. This is done by evaluating the governance of water resources in the Jaguaribe basin in the semi-arid Northeast of Brazil. The results show that common-pool resource concepts offer valuable insights for explaining variations in water resource use and availability at the river basin scale. The water system in a river basin can be characterized as one large CPR consisting of asymmetrically linked smaller CPR’s. This study showed that CPR concepts are useful for explaining agricultural productivity, stability and equitability in a semi-arid river basin. The asymmetry of a river basin CPR is the cause of unidirectional externalities towards downstream. The topography, the sequence of rainfall events and distribution of reservoir capacities in a river basin strongly\ud
influence the extent to which convergence of resource flow can compensate for these externalities
Current-phase relations of few-mode InAs nanowire Josephson junctions
Gate-tunable semiconductor nanowires with superconducting leads have great
potential for quantum computation and as model systems for mesoscopic Josephson
junctions. The supercurrent, , versus the phase, , across the junction
is called the current-phase relation (CPR). It can reveal not only the
amplitude of the critical current, but also the number of modes and their
transmission. We measured the CPR of many individual InAs nanowire Josephson
junctions, one junction at a time. Both the amplitude and shape of the CPR
varied between junctions, with small critical currents and skewed CPRs
indicating few-mode junctions with high transmissions. In a gate-tunable
junction, we found that the CPR varied with gate voltage: Near the onset of
supercurrent, we observed behavior consistent with resonant tunneling through a
single, highly transmitting mode. The gate dependence is consistent with
modeled subband structure that includes an effective tunneling barrier due to
an abrupt change in the Fermi level at the boundary of the gate-tuned region.
These measurements of skewed, tunable, few-mode CPRs are promising both for
applications that require anharmonic junctions and for Majorana readout
proposals
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Prospective Evaluation of Cardiopulmonary Resuscitation Performed in Dogs and Cats According to the RECOVER Guidelines. Part 1: Prognostic Factors According to Utstein-Style Reporting.
Factors associated with positive cardiopulmonary resuscitation (CPR) outcomes defined according to the veterinary Utstein-style CPR reporting guidelines have not been described since implementation of the Reassessment Campaign on Veterinary Resuscitation (RECOVER) CPR clinical guidelines in 2012. The aims of this study were to assess factors associated with positive CPR outcomes at a U.S. veterinary teaching hospital, to re-evaluate these factors since implementation of the RECOVER guidelines compared to reported factors prior to their publication, and to identify potential additional factors since guideline publication. One-hundred and seventy-two dogs and 47 cats that experienced cardiopulmonary arrest (CPA) and had CPR performed were prospectively included in this observational study. Supervising clinicians were asked to complete a data form on CPR events immediately following completion of CPR efforts. Multivariable logistic regression was used to evaluate the effect of twenty hospital, animal, and arrest variables on the three patient outcomes "any return of spontaneous circulation (ROSC)," "sustained ROSC," and survival to hospital discharge. Cats had significantly higher odds to achieve any ROSC [OR (95%CI) 2.72 (1.12-6.61), p = 0.028] and survive to hospital discharge than dogs [OR (95%CI) 4.87 (1.52-15.58), p = 0.008]. Patients had significantly lower odds of achieving any ROSC if CPA occurred during nighttime hours [OR (95%CI) nighttime = 0.52 (0.27-0.98), p = 0.043], and higher odds if CPA was witnessed [OR (95%CI) 3.45 (1.57-7.55), p = 0.002], if less people were involved in CPR efforts [OR (95%CI) 0.8 (0.66-0.96), p = 0.016], if pulses were palpable during CPR [OR (95%CI) 9.27 (4.16-20.63), p < 0.0005], and if an IV catheter was already in place at the time of CPA [OR (95%CI) 5.07 (2.12-12.07), p = 0.0003]. Odds for survival to hospital discharge were significantly higher if less people were involved in CPR efforts [OR (95%CI) 0.65 (0.46-0.91), p = 0.013] and for patients of the anesthesia service [OR (95%CI) 14.82 (3.91-56.17), p = 0.00007]. Overall, factors associated with improved CPR outcomes have remained similar since incorporation of RECOVER guidelines into daily practice. Witnessed CPA events and high-quality CPR interventions were associated with positive patient outcomes, emphasizing the importance of timely recognition and initiation of CPR efforts. An optimal CPR team size has yet to be determined
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