Perioperative mortality after cardiac surgery has decreased in recent years although postoperative morbidity is still significant. Although there is evidence that perioperative goal-directed ...haemodynamic therapy (GDT) may reduce surgical mortality and morbidity in non-cardiac surgical patients, the data are less clear after cardiac surgery. The objective of this review is to perform a meta-analysis on the effects of perioperative GDT on mortality, morbidity, and length of hospital stay in cardiac surgical patients.
We conducted a systematic review using Medline, EMBASE, and the Cochrane Controlled Clinical Trials Register. Additional sources were sought from experts. The inclusion criteria were randomized controlled trials, mortality reported as an outcome, pre-emptive haemodynamic intervention, and cardiac surgical population. Included studies were examined in full and subjected to quantifiable analysis, subgroup analysis, and sensitivity analysis where possible. Data synthesis was obtained by using odds ratio (OR) and mean difference (MD) for continuous data with 95% confidence interval (CI) utilizing a random-effects model.
From 4986 potential studies, 5 met all the inclusion criteria (699 patients). The quantitative analysis showed that the use of GDT reduced the postoperative complication rate (OR 0.33, 95% CI 0.15–0.73; P=0,006) and hospital length of stay (MD −2.44, 95% CI −4.03 to −0.84; P=0,003). There was no significant reduction in mortality.
The use of pre-emptive GDT in cardiac surgery reduces morbidity and hospital length of stay.
Sepsis-induced myocardial dysfunction is associated with poor outcomes, but traditional measurements of systolic function such as left ventricular ejection fraction (LVEF) do not directly correlate ...with prognosis. Global longitudinal strain (GLS) utilizing speckle-tracking echocardiography (STE) could be a better marker of intrinsic left ventricular (LV) function, reflecting myocardial deformation rather than displacement and volume changes. We sought to investigate the prognostic value of GLS in patients with sepsis and/or septic shock.
We conducted a systematic review (PubMed and Embase up to 26 October 2017) and meta-analysis to investigate the association between GLS and mortality at longest follow up in patients with severe sepsis and/or septic shock. In the primary analysis, we included studies reporting transthoracic echocardiography data on GLS according to mortality. A secondary analysis evaluated the association between LVEF and mortality including data from studies reporting GLS.
We included eight studies in the primary analysis with a total of 794 patients (survival 68%, n = 540). We found a significant association between worse LV function and GLS values and mortality: standard mean difference (SMD) - 0.26; 95% confidence interval (CI) - 0.47, - 0.04; p = 0.02 (low heterogeneity, I
= 43%). No significant association was found between LVEF and mortality in the same population of patients (eight studies; SMD, 0.02; 95% CI - 0.14, 0.17; p = 0.83; no heterogeneity, I
= 3%).
Worse GLS (less negative) values are associated with higher mortality in patients with severe sepsis or septic shock, while such association is not valid for LVEF. More critical care research is warranted to confirm the better ability of STE in demonstrating underlying intrinsic myocardial disease compared to LVEF.
Summary
The first person‐to‐person transmission of the 2019 novel coronavirus in Italy on 21 February 2020 led to an infection chain that represents one of the largest known COVID‐19 outbreaks ...outside Asia. In northern Italy in particular, we rapidly experienced a critical care crisis due to a shortage of intensive care beds, as we expected according to data reported in China. Based on our experience of managing this surge, we produced this review to support other healthcare services in preparedness and training of hospitals during the current coronavirus outbreak. We had a dedicated task force that identified a response plan, which included: (1) establishment of dedicated, cohorted intensive care units for COVID‐19–positive patients; (2) design of appropriate procedures for pre‐triage, diagnosis and isolation of suspected and confirmed cases; and (3) training of all staff to work in the dedicated intensive care unit, in personal protective equipment usage and patient management. Hospital multidisciplinary and departmental collaboration was needed to work on all principles of surge capacity, including: space definition; supplies provision; staff recruitment; and ad hoc training. Dedicated protocols were applied where full isolation of spaces, staff and patients was implemented. Opening the unit and the whole hospital emergency process required the multidisciplinary, multi‐level involvement of healthcare providers and hospital managers all working towards a common goal: patient care and hospital safety. Hospitals should be prepared to face severe disruptions to their routine and it is very likely that protocols and procedures might require re‐discussion and updating on a daily basis.
ABSTRACT
Stellar magnetic activity produces time-varying distortions in the photospheric line profiles of solar-type stars. These lead to systematic errors in high-precision radial-velocity ...measurements, which limit efforts to discover and measure the masses of low-mass exoplanets with orbital periods of more than a few tens of days. We present a new data-driven method for separating Doppler shifts of dynamical origin from apparent velocity variations arising from variability-induced changes in the stellar spectrum. We show that the autocorrelation function (ACF) of the cross-correlation function used to measure radial velocities is effectively invariant to translation. By projecting the radial velocities on to a subspace labelled by the observation identifiers and spanned by the amplitude coefficients of the ACF’s principal components, we can isolate and subtract velocity perturbations caused by stellar magnetic activity. We test the method on a 5-yr time sequence of 853 daily 15-min observations of the solar spectrum from the HARPS-N instrument and solar-telescope feed on the 3.58-m Telescopio Nazionale Galileo. After removal of the activity signals, the heliocentric solar velocity residuals are found to be Gaussian and nearly uncorrelated. We inject synthetic low-mass planet signals with amplitude K = 40 cm s−1 into the solar observations at a wide range of orbital periods. Projection into the orthogonal complement of the ACF subspace isolates these signals effectively from solar activity signals. Their semi-amplitudes are recovered with a precision of ∼ 6.6 cm s−1, opening the door to Doppler detection and characterization of terrestrial-mass planets around well-observed, bright main-sequence stars across a wide range of orbital periods.
Abstract
The time-variable velocity fields of solar-type stars limit the precision of radial-velocity determinations of their planets’ masses, obstructing detection of Earth twins. Since 2015 July, ...we have been monitoring disc-integrated sunlight in daytime using a purpose-built solar telescope and fibre feed to the HARPS-N stellar radial-velocity spectrometer. We present and analyse the solar radial-velocity measurements and cross-correlation function (CCF) parameters obtained in the first 3 yr of observation, interpreting them in the context of spatially resolved solar observations. We describe a Bayesian mixture-model approach to automated data-quality monitoring. We provide dynamical and daily differential-extinction corrections to place the radial velocities in the heliocentric reference frame, and the CCF shape parameters in the sidereal frame. We achieve a photon-noise-limited radial-velocity precision better than 0.43 m s−1 per 5-min observation. The day-to-day precision is limited by zero-point calibration uncertainty with an RMS scatter of about 0.4 m s−1. We find significant signals from granulation and solar activity. Within a day, granulation noise dominates, with an amplitude of about 0.4 m s−1 and an autocorrelation half-life of 15 min. On longer time-scales, activity dominates. Sunspot groups broaden the CCF as they cross the solar disc. Facular regions temporarily reduce the intrinsic asymmetry of the CCF. The radial-velocity increase that accompanies an active-region passage has a typical amplitude of 5 m s−1 and is correlated with the line asymmetry, but leads it by 3 d. Spectral line-shape variability thus shows promise as a proxy for recovering the true radial velocity.
Tocilizumab is an IL-6 receptor-blocking agent proposed for the treatment of severe COVID-19. The aim of this systematic review was to describe the rationale for the use of tocilizumab for the ...treatment of COVID-19 and to summarize the available evidence regarding its efficacy and safety.
MEDLINE, PubMed, EMBASE, pre-print repositories (bioRxiv and medRxiv) and two trial Registries were searched for studies on the use of tocilizumab in COVID-19 or SARS-CoV-2 infection, viral pneumonia, and/or sepsis until 20th June 2020.
We identified 3 indirect pre-clinical studies and 28 clinical studies including 5776 patients with COVID-19 (13 with a comparison group, 15 single-arm). To date, no randomized trials have been published. We retrieved no studies at low risk of bias. Forty-five ongoing studies were retrieved from trial registries.
There is insufficient evidence regarding the clinical efficacy and safety of tocilizumab in patients with COVID-19. Its use should be considered experimental, requiring ethical approval and clinical trial oversight.
Summary
Pre‐oxygenation is an essential part of rapid sequence induction of general anaesthesia for emergency surgery, in order to increase the oxygen reservoir in the lungs. We performed a ...randomised controlled trial of transnasal humidified rapid insufflation ventilatory exchange (THRIVE) pre‐oxygenation or facemask pre‐oxygenation in patients undergoing emergency surgery. Twenty patients were allocated to each group. No patient developed arterial oxygen saturation < 90% during attempted tracheal intubation. Arterial blood gases were sampled from an arterial catheter immediately after intubation. The mean (SD) PaO2 was 43.7 (15.2) kPa in the THRIVE group vs. 41.9 (16.2) kPa in the facemask group (p = 0.722); PaCO2 was 5.8 (1.1) kPa in the THRIVE group vs. 5.6 (1.0) kPa in the facemask group (p = 0.631); arterial pH was 7.36 (0.05) in the THRIVE group vs. 7.34 (0.06) in the facemask group (p = 0.447). No airway rescue manoeuvres were needed, and there were no differences in the number of laryngoscopy attempts between the groups. In spite of this, patients in the THRIVE group had a significantly longer apnoea time of 248 (71) s compared with 123 (55) s in the facemask group (p < 0.001). Transnasal humidified rapid insufflation ventilatory exchange is a practicable method for pre‐oxygenating patients during rapid sequence induction of general anaesthesia for emergency surgery; we found that it maintained an equivalent blood gas profile to facemask pre‐oxygenation, in spite of a significantly longer apnoea time.
Myocardial dysfunction may contribute to circulatory failure in sepsis. There is growing evidence of an association between left ventricular diastolic dysfunction (LVDD) and mortality in septic ...patients. Utilizing echocardiography, we know that tissue Doppler imaging (TDI) variables e′ and E/e′ are reliable predictors of LVDD and are useful measurements to estimate left ventricular (LV) filling pressures.
We conducted a systematic review and meta-analysis to investigate the association of e′ and E/e′ with mortality of patients with severe sepsis or septic shock. In the primary analysis, we included studies providing transthoracic TDI data for e′ and E/e′ and their association with mortality. Subgroup analyses were conducted according to myocardial regional focus of TDI assessment (septal, lateral or averaged). Three secondary analyses were performed: one included data from a transoesophageal study, another excluded studies reporting data at a very early (<6 h) or late (>48 h) stage following diagnosis, and the third pooled data only from studies excluding patients with heart valve disease.
The primary analysis included 16 studies with 1507 patients with severe sepsis and/or septic shock. A significant association was found between mortality and both lower e′ standard mean difference (SMD) 0.33; 95% confidence interval (CI): 0.05, 0.62; P=0.02 and higher E/e′ (SMD –0.33; 95% CI: –0.57, –0.10; P=0.006). In the subgroup analyses, only the lateral TDI values showed significant association with mortality (lower e′ SMD 0.45; 95% CI: 0.11, 0.78; P=0.009; higher E/e′ SMD –0.49; 95% CI: –0.76, –0.22; P=0.0003). The findings of the primary analysis were confirmed by all secondary analyses.
There is a strong association between both lower e′ and higher E/e′ and mortality in septic patients.
Context.
The solar telescope connected to HARPS-N has been observing the Sun since the summer of 2015. Such a high-cadence, long-baseline data set is crucial for understanding spurious ...radial-velocity signals induced by our Sun and by the instrument. On the instrumental side, this data set allowed us to detect sub- m s
−1
systematics that needed to be corrected for.
Aims.
The goals of this manuscript are to (i) present a new data reduction software for HARPS-N, (ii) demonstrate the improvement brought by this new software during the first three years of the HARPS-N solar data set, and (iii) release all the obtained solar products, from extracted spectra to precise radial velocities.
Methods.
To correct for the instrumental systematics observed in the data reduced with the current version of the HARPS-N data reduction software (DRS version 3.7), we adapted the newly available ESPRESSO DRS (version 2.2.3) to HARPS-N and developed new optimised recipes for the spectrograph. We then compared the first three years of HARPS-N solar data reduced with the current and new DRS.
Results.
The most significant improvement brought by the new DRS is a strong decrease in the day-to-day radial-velocity scatter, from 1.27 to 1.07 m s
−1
; this is thanks to a more robust method to derive wavelength solutions, but also to the use of calibrations closer in time. The newly derived solar radial-velocities are also better correlated with the chromospheric activity level of the Sun in the long term, with a Pearson correlation coefficient of 0.93 compared to 0.77 before, which is expected from our understanding of stellar signals. Finally, we also discuss how HARPS-N spectral ghosts contaminate the measurement of the calcium activity index, and we present an efficient technique to derive an index free of instrumental systematics.
Conclusions.
This paper presents a new data reduction software for HARPS-N and demonstrates its improvements, mainly in terms of radial-velocity precision, when applied to the first three years of the HARPS-N solar data set. Those newly reduced solar data, representing an unprecedented time series of 34 550 high-resolution spectra and precise radial velocities, are released alongside this paper. Those data are crucial to understand stellar activity signals in solar-type stars further and develop the mitigating techniques that will allow us to detect other Earths.
PDF
