Rationale and study design of PROVHILO - a worldwide multicenter randomized controlled trial on protective ventilation during general anesthesia for open abdominal surgery

<p>Abstract</p> <p>Background</p> <p>Post-operative pulmonary complications add to the morbidity and mortality of surgical patients, in particular after general anesthesia >2 hours for abdominal surgery. Whether a protective mechanical ventilation strategy with higher levels of positive end-expiratory pressure (PEEP) and repeated recruitment maneuvers; the "open lung strategy", protects against post-operative pulmonary complications is uncertain. The present study aims at comparing a protective mechanical ventilation strategy with a conventional mechanical ventilation strategy during general anesthesia for abdominal non-laparoscopic surgery.</p> <p>Methods</p> <p>The PROtective Ventilation using HIgh versus LOw positive end-expiratory pressure ("PROVHILO") trial is a worldwide investigator-initiated multicenter randomized controlled two-arm study. Nine hundred patients scheduled for non-laparoscopic abdominal surgery at high or intermediate risk for post-operative pulmonary complications are randomized to mechanical ventilation with the level of PEEP at 12 cmH₂O with recruitment maneuvers (the lung-protective strategy) or mechanical ventilation with the level of PEEP at maximum 2 cmH₂O without recruitment maneuvers (the conventional strategy). The primary endpoint is any post-operative pulmonary complication.</p> <p>Discussion</p> <p>The PROVHILO trial is the first randomized controlled trial powered to investigate whether an open lung mechanical ventilation strategy in short-term mechanical ventilation prevents against postoperative pulmonary complications.</p> <p>Trial registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN70332574">ISRCTN70332574</a></p

Pauli Diagonal Channels Constant on Axes

We define and study the properties of channels which are analogous to unital qubit channels in several ways. A full treatment can be given only when the dimension d is a prime power, in which case each of the (d+1) mutually unbiased bases (MUB) defines an axis. Along each axis the channel looks like a depolarizing channel, but the degree of depolarization depends on the axis. When d is not a prime power, some of our results still hold, particularly in the case of channels with one symmetry axis. We describe the convex structure of this class of channels and the subclass of entanglement breaking channels. We find new bound entangled states for d = 3. For these channels, we show that the multiplicativity conjecture for maximal output p-norm holds for p=2. We also find channels with behavior not exhibited by unital qubit channels, including two pairs of orthogonal bases with equal output entropy in the absence of symmetry. This provides new numerical evidence for the additivity of minimal output entropy

Intraoperative ventilator settings and their association with postoperative pulmonary complications in neurosurgical patients : post-hoc analysis of LAS VEGAS study

Background Limited information is available regarding intraoperative ventilator settings and the incidence of postoperative pulmonary complications (PPCs) in patients undergoing neurosurgical procedures. The aim of this post-hoc analysis of the 'Multicentre Local ASsessment of VEntilatory management during General Anaesthesia for Surgery' (LAS VEGAS) study was to examine the ventilator settings of patients undergoing neurosurgical procedures, and to explore the association between perioperative variables and the development of PPCs in neurosurgical patients. Methods Post-hoc analysis of LAS VEGAS study, restricted to patients undergoing neurosurgery. Patients were stratified into groups based on the type of surgery (brain and spine), the occurrence of PPCs and the assess respiratory risk in surgical patients in Catalonia (ARISCAT) score risk for PPCs. Results Seven hundred eighty-four patients were included in the analysis; 408 patients (52%) underwent spine surgery and 376 patients (48%) brain surgery. Median tidal volume (V-T) was 8 ml [Interquartile Range, IQR = 7.3-9] per predicted body weight; median positive end-expiratory pressure (PEEP) was 5 [3 to 5] cmH(2)0. Planned recruitment manoeuvres were used in the 6.9% of patients. No differences in ventilator settings were found among the sub-groups. PPCs occurred in 81 patients (10.3%). Duration of anaesthesia (odds ratio, 1.295 [95% confidence interval 1.067 to 1.572]; p = 0.009) and higher age for the brain group (odds ratio, 0.000 [0.000 to 0.189]; p = 0.031), but not intraoperative ventilator settings were independently associated with development of PPCs. Conclusions Neurosurgical patients are ventilated with low V-T and low PEEP, while recruitment manoeuvres are seldom applied. Intraoperative ventilator settings are not associated with PPCs

Perioperative Nutrition: Recommendations from the ESPEN Expert Group

Background and aims: Malnutrition has been recognized as a major risk factor for adverse postoperative outcomes. The ESPEN Symposium on perioperative nutrition was held in Nottingham, UK, on 14-15 October 2018 and the aims of this document were to highlight the scientific basis for the nutritional and metabolic management of surgical patients. Methods: This paper represents the opinion of experts in this multidisciplinary field and those of a patient and caregiver, based on current evidence. It highlights the current state of the art. Results: Surgical patients may present with varying degrees of malnutrition, sarcopenia, cachexia, obesity and myosteatosis. Preoperative optimization can help improve outcomes. Perioperative fluid therapy should aim at keeping the patient in as near zero fluid and electrolyte balance as possible. Similarly, glycemic control is especially important in those patients with poorly controlled diabetes, with a stepwise increase in the risk of infectious complications and mortality per increasing HbA1c. Immobilization can induce a decline in basal energy expenditure, reduced insulin sensitivity, anabolic resistance to protein nutrition and muscle strength, all of which impair clinical outcomes. There is a role for pharmaconutrition, pre-, pro- and syn-biotics, with the evidence being stronger in those undergoing surgery for gastrointestinal cancer. Conclusions: Nutritional assessment of the surgical patient together with the appropriate interventions to restore the energy deficit, avoid weight loss, preserve the gut microbiome and improve functional performance are all necessary components of the nutritional, metabolic and functional conditioning of the surgical patient

Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study

BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P &lt; 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P &lt; 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223

Medicine / Does the choice of intraoperative fluid modify abdominal aneurysm repair outcomes? : A cohort analysis

Intraoperatively administered hydroxyethyl starch could be a risk indicator for postoperative acute kidney injury (AKI) in vascular surgical patients. In a single-center retrospective cohort analysis, we assessed the impact of hydroxyethyl starch and other risk indicators on AKI and mortality in 1095 patients undergoing elective open abdominal aneurysm repair (AAA-OR) or endovascular aortic repair (EVAR). We established logistic regression models to determine the effect of various risk indicators, including hydroxyethyl starch, on AKI, as well as Cox proportional hazard models to assess the effect on mortality. The use of intravenous hydroxyethyl starch was not associated with an increased risk of AKI or mortality. Patients undergoing EVAR were less likely to develop AKI (4% vs 18%). Multivariate risk indicators associated for AKI included suprarenal or pararenal aortic cross-clamp [odds ratio (OR), 4.44; 95% confidence interval (95% CI), 2.5387.784; P < .001] and procedure length (OR, 1.005; 95% CI, 1.0031.007; P < .001), and favored EVAR (OR, 0.351; 95% CI, 0.1180.654; P < .01). Main multivariate risk indicators associated with mortality included patients needing an urgent procedure [hazard ratio (HR), 2.294; 95% CI, 1.5413.413; P < .001], those with suprarenal or pararenal aortic cross-clamp (HR, 1.756; 95% CI, 1.2472.472; P < .01), and patients undergoing EVAR (HR, 1.654; 95% CI, 1.2922.118; P < .001). We found neither a benefit nor a negative effect of hydroxyethyl starch on the risk of AKI or mortality. Instead, other variables and comorbidities were found to be relevant for the development of postoperative AKI and survival. Nevertheless, clinicians should be aware of the high risk of postoperative AKI, particularly among those undergoing AAA-OR procedures.(VLID)489229

PLOS ONE / Transfusion of standard-issue packed red blood cells induces pulmonary vasoconstriction in critically ill patients after cardiac surgeryA randomized, double-blinded, clinical trial

Background Experimental and volunteer studies have reported pulmonary vasoconstriction during transfusion of packed red blood cells (PRBCs) stored for prolonged periods. The primary aim of this study was to evaluate whether transfusion of PRBCs stored over 21 days (standard-issue, siPRBCs) increases pulmonary artery pressure (PAP) to a greater extent than transfusion of PRBCs stored for less then 14 days (fresh, fPRBCs) in critically ill patients following cardiac surgery. The key secondary aim was to assess whether the pulmonary vascular resistance index (PVRI) increases after transfusion of siPRBCs to a greater extent than after transfusion of fPRBCs. Methods The study was performed as a single-center, double-blinded, parallel-group, randomized clinical trial. Leukoreduced PRBCs were transfused while continuously measuring hemodynamic parameters. Systemic concentrations of syndecan-1 were measured to assess glycocalyx injury. After randomizing 19 patients between January 2014 and June 2016, the study was stopped due to protracted patient recruitment. Results Of 19 randomized patients, 11 patients were transfused and included in statistical analyses. Eight patients were excluded prior to transfusion, 6 patients received fPRBCs (103 storage days), whereas 5 patients received siPRBCs (334 storage days). The increase in PAP (73 vs. 22 mmHg, P = 0.012) was greater during transfusion of siPRBCs than during transfusion of fPRBCs. In addition, the change in PVRI (15089 vs. -437 dyn·s·cm·m, P = 0.018) was greater after transfusion of siPRBCs than after transfusion of fPRBCs. The increase in PAP correlated with the change of systemic syndecan-1 concentrations at the end of transfusion (R = 0.64,P = 0.034). Conclusion Although this study is underpowered and results require verification in larger clinical trials, our findings suggest that transfusion of siPRBCs increases PAP and PVRI to a greater extent than transfusion of fPRBCs in critically ill patients following cardiac surgery. Glycocalyx injury might contribute to pulmonary vasoconstriction associated with transfusion of stored blood.(VLID)495023

Predictors of incident malnutrition—a nutritionDay analysis in 11,923 nursing home residents

Background/Objectives: Malnutrition (MN) in nursing home (NH) residents is associated with poor outcome. In order to identify those with a high risk of incident MN, the knowledge of predictors is crucial. Therefore, we investigated predictors of incident MN in older NH-residents. Subjects/Methods: NH-residents participating in the nutritionDay-project (nD) between 2007 and 2018, aged ≥65 years, with complete data on nutritional status at nD and after 6 months and without MN at nD. The association of 17 variables (general characteristics (n = 3), function (n = 4), nutrition (n = 1), diseases (n = 5) and medication (n = 4)) with incident MN (weight loss ≥ 10% between nD and follow-up (FU) or BMI (kg/m2) < 20 at FU) was analyzed in univariate generalized estimated equation (GEE) models. Significant (p < 0.1) variables were selected for multivariate GEE-analyses. Effect estimates are presented as odds ratios and their respective 99.5%-confidence intervals. Results: Of 11,923 non-malnourished residents, 10.5% developed MN at FU. No intake at lunch (OR 2.79 [1.56–4.98]), a quarter (2.15 [1.56–2.97]) or half of the meal eaten (1.72 [1.40–2.11]) (vs. three-quarter to complete intake), the lowest BMI-quartile (20.0–23.0) (1.86 [1.44–2.40]) (vs. highest (≥29.1)), being between the ages of 85 and 94 years (1.46 [1.05; 2.03]) (vs. the youngest age-group 65–74 years)), severe cognitive impairment (1.38 [1.04; 1.84]) (vs. none) and being immobile (1.28 [1.00–1.62]) (vs. mobile) predicted incident MN in the final model. Conclusion: 10.5% of non-malnourished NH-residents develop MN within 6 months. Attention should be paid to high-risk groups, namely residents with poor meal intake, low BMI, severe cognitive impairment, immobility, and older age