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Dysfunctional labor is a common cause of cesarean delivery and may be caused by myometrial hypoxia. Obstruction of uterine venous return due to compression of the inferior vena cava by the gravid uterus or the abdominal wall may be an auxiliary cause of myometrial hypoxia which aggravates other causes.
Subject(s)
Abdominal Wall/pathology , Cesarean Section/adverse effects , Dystocia/pathology , Hypoxia/physiopathology , Myometrium/physiopathology , Uterus/pathology , Vena Cava, Inferior/pathology , Dystocia/etiology , Female , Humans , Muscle Contraction , PregnancyABSTRACT
Early administration of blood products is emerging as best practice in selected trauma and medical patients. Blood products carried by critical care transport (CCT) teams are sometimes the first available to critically ill and injured patients. The purpose of this research was to evaluate the introduction of prehospital transfusion into a paramedic-led CCT program in Canada. A retrospective review of electronic patient care records for all patients who received a prehospital transfusion of uncrossmatched group O packed red blood cells between February 10, 2019, and September 30, 2020, was conducted. Forty-eight patients received a prehospital transfusion. The median age of the patients was 44 years, 81.3% were male, and most patients were victims of blunt trauma. Packed red blood cells were associated with a significant increase in systolic blood pressure (P < .001) and mean arterial pressure (P < .001), a decrease in shock index (P < .001), and a reduction in the time to first transfusion, with minimal waste, no patient-related adverse events, and complete traceability. The results of this service evaluation demonstrate the successful introduction of prehospital transfusion into a paramedic-led CCT program. Further prospective research is needed to assess the impact of such a protocol in this patient population.
Subject(s)
Emergency Medical Services , Wounds and Injuries , Adult , Allied Health Personnel , Blood Transfusion , British Columbia , Critical Care , Humans , Male , Retrospective StudiesABSTRACT
To validate electrical cardiometry (EC) in pregnant patients using transthoracic echocardiography (TTE) as the reference standard. To improve EC accuracy via a one-time, measurement of left ventricular outflow tract (LVOT) diameter. 44 non-laboring, resting women with singleton, viable pregnancies underwent simultaneous EC and TTE measurements. Data were analyzed using Bland-Altman analysis. Entry multiple regression with stepwise elimination was used to develop a model for improved prediction of stroke volume by TTE (SVTTE) using EC. Bootstrapping and an 11-fold cross validation were used to test the model. Heart rate by TTE and EC had a mean bias of 3.3 beats/min and mean percentage error of 10.7 %. Envelope time and left ventricular ejection time had a mean bias of -4.9 ms and mean percentage error 12.7 %. Stroke volumes by the two techniques had a mean bias of 15.6 mL and mean percentage error of 43.7 %. A model, SVEC_Modified, predicting SVTTE was developed using LVOT area, stroke volume by electrical cardiometry and weight. SVTTE and SVEC_Modified had a mean bias of -0.83 mL and mean percentage error of 22 %. EC accurately measures heart rate and duration of systole when compared with TTE. Stroke volume measurements correlate but have a high bias and percentage error. Knowledge of LVOT area, by a one-time, measurement with TTE, could improve prediction of stroke volume by EC.
Subject(s)
Aortic Valve Stenosis/physiopathology , Echocardiography/methods , Heart Ventricles/physiopathology , Stroke Volume/physiology , Adult , Cardiac Output , Cross-Sectional Studies , Female , Heart Rate/physiology , Hemodynamics , Humans , Models, Statistical , Monitoring, Physiologic/methods , Pregnancy , Prospective Studies , Reference Standards , Regression Analysis , Reproducibility of Results , Systole/physiology , Young AdultABSTRACT
Background and study aims The aim of this study was to assess the effect of an educational video on the quality of bowel preparation of patients from a UK population attending for their first colonoscopy. Patients and methods A prospective, endoscopist-blinded trial with 1:1 allocation was performed. Patients referred for their first colonoscopy were recruited between February 2019 and December 2019. All participants were prescribed Moviprep and received the trial site's standard written bowel preparation instructions, with the intervention group also receiving a bespoke educational video. Adequacy of bowel preparation (defined as a Boston Bowel Preparation Scale of ≥2 in each segment of the bowel) and polyp detection rates (PDRs) were compared. Fisher's chi squared test was utilized with P <0.05 as the threshold for significance. Results A total of 509 participants completed the trial from six centers; 251 were randomized to the intervention group. The mean age was 57 years and 52.3% were female. The primary endpoint was met with an adequacy rate of 216 of 251 (86.1%) in the intervention group, compared with 205 of 259 (79.1%) in the control group ( P <0.05, odds ratio [OR] 1.626, 95% CI 1.017-2.614). The PDR was significantly higher in the intervention group (39% vs 30%, OR 1.51, 95% CI 1.04-2.19, P <0.05). Conclusions An educational video leads to improved bowel preparation for patients attending for their first colonoscopy, and is also associated with greater detection of polyps. Widespread adoption of an educational video incurs minimal investment, but would reduce the number of inadequate procedures, missed pathology, and the cost that both these incur.
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BACKGROUND: Measuring cardiac output accurately during anesthesia is thought to be helpful for safely controlling hemodynamics. Several minimally invasive methods to measure cardiac output have been developed as alternatives to thermodilution with pulmonary artery catheterization. We evaluated the reliability of a novel pulse wave transit time method of cardiac output assessment to trend with thermodilution cardiac output in patients undergoing partial hepatectomy. METHODS: Thirty-one patients (ASA physical status II or III) undergoing partial hepatectomy under general anesthesia were evaluated. Cardiac output measurements by pulse wave transit time method and by thermodilution were recorded after induction of anesthesia, after a change in body positioning to 20° head up, after a change to 20° head down, after volume challenge with 10 mL·kg hydroxyethyl starch 6%, during the Pringle maneuver, and immediately after Pringle maneuver release. Trending was assessed using Bland-Altman analysis and concordance analysis. RESULTS: The direction of change between consecutive pulse wave transit time measurements and the corresponding thermodilution measurements showed a concordance rate of 96.0% (lower 95% confidence interval = 64%), with limits of agreement -1.51 and 1.61 L·min. CONCLUSIONS: The pulse wave transit time method had good concordance but fairly wide limits of agreement with regard to trending in patients with changes in preload and systemic vascular resistance. There are potential inaccuracies when vasopressors are used to treat hypotension associated with decreased systemic vascular resistance. The study limitations are that the cardiac output data were collected in a nonblinded fashion, and an existing intraarterial catheter was used, although the system requires only routine, noninvasive cardiovascular monitors. This is a promising technique that currently has limitations and will require further improvements and clinical assessment.
Subject(s)
Cardiac Output , Hepatectomy/methods , Monitoring, Intraoperative/methods , Pulse Wave Analysis , Thermodilution , Aged , Aged, 80 and over , Anesthesia, General , Arterial Pressure , Female , Heart Rate , Hepatectomy/adverse effects , Humans , Male , Middle Aged , Monitoring, Intraoperative/instrumentation , Patient Positioning , Predictive Value of Tests , Pulse Wave Analysis/instrumentation , Reproducibility of Results , Time Factors , Vascular ResistanceABSTRACT
We propose, by performing advanced ab initio electron transport calculations, an all-oxide composite magnetic tunnel junction, within which both large tunneling magnetoresistance (TMR) and tunneling electroresistance (TER) effects can coexist. The TMR originates from the symmetry-driven spin filtering provided by an insulating BaTiO(3) barrier to the electrons injected from the SrRuO(3) electrodes. Following recent theoretical suggestions, the TER effect is achieved by intercalating a thin insulating layer, here SrTiO(3), at one of the SrRuO(3)/BaTiO(3) interfaces. As the complex band structure of SrTiO(3) has the same symmetry as that of BaTiO(3), the inclusion of such an intercalated layer does not negatively alter the TMR and in fact increases it. Crucially, the magnitude of the TER also scales with the thickness of the SrTiO(3) layer. The SrTiO(3) thickness becomes then a single control parameter for both the TMR and the TER effect. This protocol offers a practical way to the fabrication of four-state memory cells.
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Objectives: We aimed to identify, appraise, and synthesise the qualitative literature to develop theory on heroism and paramedic practice. Hypothesis/research question: What does published literature tell us about heroism and paramedic practice? Setting: Paramedics and other healthcare workers (HCWs) faced an outpouring of public support for them early in the COVID-19 pandemic which brought into focus the relationship between them and society, where they are portrayed as heroes. Participants: We conducted a metasynthesis using Evolved Grounded Theory and procedural guidelines of Noblit and Hare to guide analysis. Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocols (PRISMA-P) guidelines were also applied. Results: 151 papers were retrieved and eleven included in the final sample. Studies were moderate to very low quality, involving a wide range of methodologies and settings; none specifically explored heroism and paramedic practice. The following interrelated themes were constructed on heroism and paramedic practice: (a) Myth, Folk law, and storytelling in heroism and paramedic practice (b) The epic journey of heroism and paramedic practice (c) Heroes and Zeroes: The fluctuating Societal Value in heroism and paramedic practice (d) Politicisation, and objectification in Heroism and Paramedic practice. Conclusion: Paramedics have long been characterised as heroes, but this may not reflect their everyday experiences. Heroism in paramedic practice can provide scripts for prosocial action, inspiring others, and leading to more social heroic actions. Paramedics may however be ambivalent to such heroism narratives, due to politicisation, and objectification in the media and society. This metasynthesis is only one of many possible constructions of heroism and paramedic practice and is the first point in making sense of and developing theory on heroism and paramedic practice. Study registration: PROSPERO: CRD42021234851.
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Objective: The 2-week-wait (2ww) referral pathway is used in England to fast-track patients with suspected colorectal cancer (CRC). A two-stage triage pathway was used to prioritise lower gastrointestinal (LGI) endoscopy for suspected CRC during the COVID-19 pandemic. Method: All patients referred for an LGI endoscopy via a 2ww referral pathway between March 2020 and July 2020 were assessed. The first stage triaged patients to high, standard or low risk of CRC based on symptoms and faecal immunochemical test (FIT), and offered CT scans to those at high risk. The second stage, endoscopy prioritisation (EP), incorporated the CT results, FIT and symptoms to triage into four groups, EP1-EP4; with EP1 being the most urgent and EP4 the least. The primary outcome measure was CRC detection. Results: 514 patients were included. The risk of CRC was triaged as high in 190/514 patients (37%), standard in 274/514 patients (53%) and low in 50/514 (10%) patients. 422/514 patients (82%) underwent endoscopy with triage to EP1 in 52/422 (12%), EP2 in 105/422 (25%), EP3 in 210/422 (50%) and EP4 in 55/422 (13%). CRC was detected in 23 patients (5.4%). CRC was significantly more frequent in the EP1 group (23.1%, relative risk (RR)=16.2) and EP2 group (6.7%, RR=4.7) compared with EP3 group (1.4%). All CRC lesions were identified by CT imaging when performed prior to LGI endoscopy. Conclusion: This triage pathway designated 83% of patients with CRC to either EP1 or EP2. During a period of limited endoscopy provision, this pathway effectively prioritises endoscopy for those at greatest risk of CRC.
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INTRODUCTION: Pneumothorax remains an important cause of preventable trauma death. The aim of this systematic review is to synthesize the recent evidence on the efficacy, patient outcomes, and adverse events of different chest decompression approaches relevant to the out-of-hospital setting. METHODS: A comprehensive literature search was performed using five databases (from January 1, 2014 through June 15, 2020). To be considered eligible, studies required to report original data on decompression of suspected or proven traumatic pneumothorax and be considered relevant to the prehospital context. They also required to be conducted mostly on an adult population (expected more than ≥80% of the population ≥16 years old) of patients. Needle chest decompression (NCD), finger thoracostomy (FT), and tube thoracostomy were considered. No meta-analysis was performed. Level of evidence was assigned using the Harbour and Miller system. RESULTS: A total of 1,420 citations were obtained by the search strategy, of which 20 studies were included. Overall, the level of evidence was low. Eleven studies reported on the efficacy and patient outcomes following chest decompression. The most studied technique was NCD (n = 7), followed by FT (n = 5). Definitions of a successful chest decompression were heterogeneous. Subjective improvement following NCD ranged between 18% and 86% (n = 6). Successful FT was reported for between 9.7% and 32.0% of interventions following a traumatic cardiac arrest. Adverse events were infrequently reported. Nine studies presented only on anatomical measures with predicted failure and success. The mean anterior chest wall thickness (CWT) was larger than the lateral CWT in all studies except one. The predicted success rate of NCD ranged between 90% and 100% when using needle >7cm (n = 7) both for the lateral and anterior approaches. The reported risk of iatrogenic injuries was higher for the lateral approach, mostly on the left side because of the proximity with the heart. CONCLUSIONS: Based on observational studies with a low level of evidence, prehospital NCD should be performed using a needle >7cm length with either a lateral or anterior approach. While FT is an interesting diagnostic and therapeutic approach, evidence on the success rates and complications is limited. High-quality studies are required to determine the optimal chest decompression approach applicable in the out-of-hospital setting.
Subject(s)
Emergency Medical Services , Pneumothorax , Adolescent , Adult , Decompression, Surgical , Humans , Pneumothorax/etiology , Pneumothorax/surgery , ThoracostomyABSTRACT
BACKGROUND: Exceptional demands have been placed on paramedics and other healthcare workers (HCWs) during the COVID-19 pandemic. An overwhelming outpouring of public support has unfolded, bringing into focus the relationship between paramedics, other HCWs and society, where they are portrayed as heroes. Scholars have studied the notion of heroism to society, and characteristics of such heroic status include: the voluntary nature of a heroic act, risk of physical or social harm, willingness to accept the consequences of action, acting for the benefit of others and without the expectation of gain. While some HCWs and paramedics may reflect these characteristics, many may not. Such heroic narratives can be damaging, stifling meaningful discussion around limits to duties, failing to acknowledge the importance of reciprocity and potentially imposing demands on paramedics and HCWs to be heroic. AIM: This article prospectively presents the protocol for a metasynthesis which aims to identify, appraise and synthesise the qualitative literature in order to develop theory on heroism and paramedic practice. METHODS: Evolved grounded theory methodology is followed along with the procedural guidelines of Noblit and Hare (1988) to guide the analysis. The Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocols (PRISMA-P) have also been adopted when preparing this protocol and will be followed in the study proper. The protocol has been registered with the International Prospective Register of Systematic Reviews PROSPERO 2021, registration number CRD42021234851. RESULTS: We do not currently have results, but PRISMA guidelines will be followed when reporting our findings. CONCLUSION: Current narratives on heroism and paramedic practice are important in terms of the relationship between paramedics and society. The metasynthesis prospectively reported in this article serves as the first point in our journey of making sense of and developing theory on heroism and paramedic practice.
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INTRODUCTION: Adequate bowel preparation is a prerequisite for effective colonoscopy. Split bowel preparation results in optimal cleansing. This study assessed the bowel preparation regimes advised by endoscopy units across the UK, and correlated the differences with outcomes. METHODS: Trusts in the UK were surveyed, with data requested between January 2018 and January 2019, including: the type and timing of preparation, pre-endoscopy diet, adequacy rates and polyp detection. Trusts were grouped according to the timing of bowel preparation. χ2 test was used to assess for differences in bowel preparation adequacy. RESULTS: Moviprep was the first line bowel preparation in 79% of trusts. Only 7% of trusts advised splitting bowel preparation for all procedures, however, 91% used split bowel preparation for afternoon procedures. Trusts that split preparation for all procedures had an inadequacy rate of 6.7%, compared with 8.5% (p<0.001) for those that split preparation for PM procedures alone and 9.5% (p<0.001) for those that provided day before preparation for all procedures. Morning procedures with day-before preparation had a higher rate of inadequate cleansing than afternoon procedures that received split preparation (7.7% vs 6.5 %, p<0.001). The polyp detection rate for procedures with adequate preparation was 37.1%, compared with 26.4% for those that were inadequate. CONCLUSION: Most trusts in the UK do not provide instructions optimising the timing of bowel preparation prior to colonoscopy. This correlated with an increased rate of inadequate cleansing. Splitting bowel preparation is likely to reduce the impacts of poor cleansing: missed lesions, repeat colonoscopies and significant costs.
Subject(s)
Cathartics , Colonoscopy , Diet , Intestines , United KingdomABSTRACT
Recently magnetic tunnel junctions using two-dimensional MoS2 as nonmagnetic spacer have been fabricated, although their magnetoresistance has been reported to be quite low. This may be attributed to the use of permalloy electrodes, injecting current with a relatively small spin polarization. Here we evaluate the performance of MoS2-based tunnel junctions using Fe3Si Heusler alloy electrodes. Density functional theory and the non-equilibrium Green's function method are used to investigate the spin injection efficiency (SIE) and the magnetoresistance (MR) ratio as a function of the MoS2 thickness. We find a maximum MR of ~300% with a SIE of about 80% for spacers comprising between 3 and 5 MoS2 monolayers. Most importantly, both the SIE and the MR remain robust at finite bias, namely MR > 100% and SIE > 50% at 0.7 V. Our proposed materials stack thus demonstrates the possibility of developing a new generation of performing magnetic tunnel junctions with layered two-dimensional compounds as spacers.
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Magnetic materials underpin modern technologies, ranging from data storage to energy conversion to contactless sensing. However, the development of a new high-performance magnet is a long and often unpredictable process, and only about two dozen magnets are featured in mainstream applications. We describe a systematic pathway to the design of novel magnetic materials, which demonstrates a high throughput and discovery speed. On the basis of an extensive electronic structure library of Heusler alloys containing 236,115 prototypical compounds, we filtered those displaying magnetic order and established whether they can be fabricated at thermodynamic equilibrium. Specifically, we carried out a full stability analysis of intermetallic Heusler alloys made only of transition metals. Among the possible 36,540 prototypes, 248 were thermodynamically stable but only 20 were magnetic. The magnetic ordering temperature, TC, was estimated by a regression calibrated on the experimental TC of about 60 known compounds. As a final validation, we attempted the synthesis of a few of the predicted compounds and produced two new magnets: Co2MnTi, which displays a remarkably high TC in perfect agreement with the predictions, and Mn2PtPd, which is an antiferromagnet. Our work paves the way for large-scale design of novel magnetic materials at potentially high speed.
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Cytokines orchestrate immune and inflammatory responses involved in the pathogenesis of ulcerative colitis (UC). Protein kinases are essential for signal transduction in eukaryotic cells. Janus kinases (JAKs) are a family of protein tyrosine kinases that play a pivotal role in cytokine receptor signaling. Indeed, a major subgroup of cytokines use Type I and II cytokine receptors which signal via the activation of JAKs. Tofacitinib is an oral JAK inhibitor that has been studied in autoimmune pathologies, including UC and rheumatoid arthritis with good overall efficacy and acceptable safety profile. This literature review was performed with the goal of summarizing the knowledge on JAK inhibitors in UC treatment.
Subject(s)
Arthritis, Rheumatoid/drug therapy , Colitis, Ulcerative/drug therapy , Janus Kinases/antagonists & inhibitors , Piperidines/therapeutic use , Protein Kinase Inhibitors/therapeutic use , Pyrimidines/therapeutic use , Pyrroles/therapeutic use , Animals , Autoimmunity , Cytokines/metabolism , Humans , Signal TransductionSubject(s)
Aorta/physiopathology , Cardiac Output/physiology , Monitoring, Intraoperative/instrumentation , Perioperative Care/instrumentation , Stroke Volume , Aorta/diagnostic imaging , Humans , Models, Theoretical , Monitoring, Intraoperative/methods , Perioperative Care/methods , Systole , Ultrasonography, Doppler/methodsABSTRACT
A 23 year-old woman with chronic hypertension, focal segmental glomerular sclerosis with chronic renal insufficiency, and superimposed severe preeclampsia, required cesarean delivery. The patient's course was also complicated by severe hyperkalemia and hypermagnesemia. "PulseCO" pulse contour analysis of a directly measured radial artery pressure tracing, without lithium calibration, enabled her physicians to follow trends in cardiac output and systemic vascular resistance, facilitating and rationalizing her care. The limitations of pulse contour analysis are discussed.