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The method of packing conventional proppant into fractures is used to maintain high liquid permeability. In this study, by coating a hydrophobic material on the surface of a proppant, the layer packed with this coated proppant was endowed with water-plugging and oil-permeability capacities. Moreover, several research experiments were carried out to verify the proposed method: a water plugging capacity (WPC) test of the coated proppant layer, compression and temperature resistance tests of the coated proppant (temperature range from 90 to 210 °C; pressure range from 5.9 to 91.4 MPa), and a 3D test of the oil recovery enhancement. The results show that the proppant coating has good compression resistance, and the proppant begins to break at 27.3 MPa. The upper limit of the temperature resistance of the coating is 170 °C. The WPC of the layer packed with coated proppant was still reliable during fracture, which was enhanced by at least 20% compared with that of the layer packed with a conventional proppant. The fracture packed with the coated proppant had superior working performance compared with that packed with a conventional proppant. It can reduce the flow capacity of the water phase breaking into the dominant flow passage so as to delay the rise in the water production of the oil well and prolong the duration of oil production. In this way, oil recovery could be increased by about 7.7%. In conclusion, the technology proposed in this paper has particular water-plugging and oil-permeating characteristics, with remarkable technical advantages, thus providing a new idea for the development of water control in fracture reservoirs.

Construction of ML-hGRN for the salt pathway in Populus davidiana × P. bolleana. Construction of ML-hGRN for the lignocellulosic pathway in Populus davidiana × P. bolleana under salt stress. Many woody plants, including Populus davidiana × P. bolleana, have made great contributions to human production and life. High salt is one of the main environmental factors that restricts the growth of poplar. This study found that high salt could induce strong biochemical changes in poplar. To detect the effect of salt treatment on gene expression, 18 libraries were sequenced on the Illumina sequencing platform. The results identified a large number of early differentially expressed genes (DEGs) and a small number of late DEGs, which indicated that most of the salt response genes of poplar were early response genes. In addition, 197 TFs, including NAC, ERF, and other TFs related to salt stress, were differentially expressed during salt treatment, which indicated that these TFs may play an important role in the salt stress response of poplar. Based on the RNA-seq analysis results, multilayered hierarchical gene regulatory networks (ML-hGRNs) of salt stress- and lignocellulosic synthesis-related DEGs were constructed using the GGM algorithm. The lignocellulosic synthesis regulatory network under salt stress revealed that lignocellulosic synthesis might play an important role in the process of salt stress resistance. Furthermore, the NAC family transcription factor PdbNAC83, which was found in the upper layer in both pathways, was selected to verify the accuracy of the ML-hGRNs. DAP-seq showed that the binding site of PdbNAC83 included a "TT(G/A)C(G/T)T" motif, and ChIP-PCR further verified that PdbNAC83 can regulate the promoters of at least six predicted downstream genes (PdbNLP2-2, PdbZFP6, PdbMYB73, PdbC2H2-like, PdbMYB93-1, PdbbHLH094) by binding to the "TT(G/A)C(G/T)T" motif, which indicates that the predicted regulatory network diagram obtained in this study is relatively accurate. In conclusion, a species-specific salt response pathway might exist in poplar, and this finding lays a foundation for further study of the regulatory mechanism of the salt stress response and provides new clues for the use of genetic engineering methods to create high-quality and highly resistant forest germplasms.

Large scale polymer flooding in Daqing Oilfield achieved great success. The average recovery degree of these oilfields after polymer flooding has reached 52.5%, and the average water cut has reached 96.0%. It is urgent to find an effective technical method for further EOR. Targeting the highly dispersed remaining oil in the post polymer flooding reservoirs, the continuous phase polymer solution in ASP technology was replaced by nano-micron particle polymer dispersion to realize optimization for EOR mechanism, so the ASP technology was upgraded. The field test, has been completed the slug injection, and achieved obvious EOR effect.The ASP slug design with HPAM solution as the main displacement phase was abandoned. A type of water dispersion of nano-micron particle polymer as the main displacement phase was designed to replace the "P" in traditional ASP slug, so that the flowing control mechanism of "P" was optimized. Through synchronous diversion and displacement, it can initiate and sweep the remaining oil dispersed in relatively small pores. A large three-dimensional physical model with the size of 60 × 45 × 4.5cm was made to simulate the real development history of water injection and polymer flooding of the reservoir, based on which, the performance of the upgraded ASP was modeled. Furthermore, the program was designed and optimized by numerical simulation.The physical simulation fitting experiment of the development history of water flooding and polymer flooding shows that the coincidence rate is 93%+. After polymer flooding, the upgraded ASP further improved the recovery by 15.2 percent. The optimized scheme of numerical simulation is to inject 0.5PV of new ASP slug. Under the precondition of the historical recovery degree of 55.8% and water cut of 98.44%, the new ASP is expected to improve the recovery by 7.9% within 10 years. At present, the field test of ASP slug injection has just been completed, and remarkable results have been achieved, The daily oil production has increased by 60%, and the water oil ratio has decreased from 61.9 to 38.4. The daily oil production of some producers has increased by 2 to 3 times, and the recovery has increased by 5.2%.The field trial proves that the oil displacement mechanism of nano-micron-particle-polymer ASP flooding chemical system is more advanced and the displacement efficiency is higher than that of the traditional ASP flooding, and the oil recovery can be further enhanced for similar reservoirs under extreme conditions after polymer flooding. The traditional ASP technology is expected to have great upgrading and developing.

The effective pollutant removal with environmentally friendly material has attracted a lot of attention. Macroporous polyHIPE-g-poly(glycidyl methacrylate)-β-cyclodextrin (a) was prepared via the combination of high internal phase emulsion (HIPE) polymerization,...

OBJECTIVE: Coagulopathy is one of the characteristics observed in critically ill patients with coronavirus disease 2019 (COVID-19). Antiphospholipid antibodies (aPLs) contribute to coagulopathy, though their role in COVID-19 remains unclear. This study was undertaken to determine the prevalence and characteristics of aPLs in patients with COVID-19. METHODS: Sera collected from 66 COVID-19 patients who were critically ill and 13 COVID-19 patients who were not critically ill were tested by chemiluminescence immunoassay for anticardiolipin antibodies (aCLs), anti-s2 -glycoprotein I (anti-s2 GPI) (IgG, IgM, and IgA), and IgG anti-s2 GPI-domain 1 (anti-s2 GPI-D1) and IgM and IgG anti-phosphatidylserine/prothrombin (anti-PS/PT) antibodies were detected in the serum by enzyme-linked immunosorbent assay. RESULTS: Of the 66 COVID-19 patients in critical condition, aPLs were detected in 31 (47% ). Antiphospholipid antibodies were not present among COVID-19 patients who were not in critical condition. The IgA anti-s2 GPI antibody was the most commonly observed aPL in patients with COVID-19 and was present in 28.8% (19 of 66) of the critically ill patients, followed by IgA aCLs (17 of 66, or 25.8%) and IgG anti-s2 GPI (12 of 66, or 18.2%). For multiple aPLs, IgA anti-s2 GPI + IgA aCLs was the most common antibody profile observed (15 of 66, or 22.7%), followed by IgA anti-s2 GPI + IgA aCL + IgG anti-s2 GPI (10 of 66, or 15.2%). Antiphospholipid antibodies emerge ~35-39 days after disease onset. A dynamic analysis of aPLs revealed 4 patterns based on the persistence or transient appearance of the aPLs. Patients with multiple aPLs had a significantly higher incidence of cerebral infarction compared to patients who were negative for aPLs (P = 0.023). CONCLUSION: Antiphospholipid antibodies were common in critically ill patients with COVID-19. Repeated testing demonstrating medium to high titers of aPLs and the number of aPL types a patient is positive for may help in identifying patients who are at risk of developing cerebral infarction. Antiphospholipid antibodies may be transient and disappear within a few weeks, but in genetically predisposed patients, COVID-19 may trigger the development of an autoimmune condition similar to the antiphospholipid syndrome (APS), referred to as "COVID-19-induced APS-like syndrome." Long-term follow-up of COVID-19 patients who are positive for aPLs would be of great importance in understanding the pathogenesis of this novel coronavirus.

Injectable and self-healing hydrogels with thermoresponsiveness as smart hydrogels displayed injectability, automatic healing, and phase and volume changes as well. Here, the thermoresponsive self-healing hydrogel was prepared via the formation of dynamic covalent enamine bonds between the amino groups in polyetherimide (PEI) and the acetoacetate groups in the four-armed star-shaped poly(2-(dimethylamino)ethyl methacrylate-co-2-hydroxyethyl methacrylate) modified with tert-butyl acetoacetate (t-BAA), SP(DMAEMA-co-HEMA-AA). After adding polydopamine nanoparticles (PDA NPs), the SP(DMAEMA-co-HEMA-AA)/PEI/PDA-NP nanocomposite hydrogel presented phase change and volume shrinkage under near-infrared (NIR) irradiation. The thermoresponsive nanocomposite hydrogel loaded with the anticancer drug doxorubicin (DOX) could be injected into the 4T1 tumor by intratumoral injection. After NIR laser irradiation, the temperature of the hydrogel increased because of the photothermal effect of PDA NPs inducing local hyperthermia. Because the hydrophilicity-hydrophobicity transition of the hydrogel occurred, DOX molecules were squeezed out from the hydrogel at temperatures higher than its lower critical solution temperature (LCST) and the tumor cells suffered from internal stress from the shrunk hydrogel. The injectable nanocomposite hydrogel not only demonstrated the synergism of highly efficient thermochemotherapy but also showed the function of improving drug utilization and precise treatment to reduce the side effects of drugs.

A dumbbell-shaped copolymer (PDMAEMA)4-PCL-SS-PCL-(PDMAEMA)4 with a lower critical solution temperature (LCST) and redox responses was first synthesized by the combination of ring opening polymerization (ROP), click chemistry and atom transfer radical polymerization (ATRP). Then a dumbbell-shaped copolymer (PDMAPS)4-PCL-SS-PCL-(PDMAPS)4 with an upper critical solution temperature (UCST) and redox responses was obtained through the quaternization reaction between DMAEMA and excess 1,3-propane sultone. Both (PDMAEMA)4-PCL-SS-PCL-(PDMAEMA)4 and (PDMAPS)4-PCL-SS-PCL-(PDMAPS)4 were amphiphilic, and they could self-assemble into spherical micelles under certain conditions. Benefitting from the LCST-type thermoresponse of PDMAEMA and UCST-type thermoresponse of PDMAPS, both dumbbell-shaped copolymers (PDMAEMA)4-PCL-SS-PCL-(PDMAEMA)4 and (PDMAPS)4-PCL-SS-PCL-(PDMAPS)4 presented temperature-responsive properties. The morphology and size of their assemblies would be changed when the temperature is altered. Meanwhile, due to the redox-response of disulfide bonds, both (PDMAEMA)4-PCL-SS-PCL-(PDMAEMA)4 and (PDMAPS)4-PCL-SS-PCL-(PDMAPS)4 showed redox-responsive properties. When DL-dithiothreitol (DTT) was added into the systems, disulfide bonds were broken, causing the change of (PDMAEMA)4-PCL-SS-PCL-(PDMAEMA)4 to PCL-(PDMAEMA)4, while (PDMAPS)4-PCL-SS-PCL-(PDMAPS)4 changed into PCL-(PDMAPS)4. The distributions of Rh for both (PDMAEMA)4-PCL-SS-PCL-(PDMAEMA)4 and (PDMAPS)4-PCL-SS-PCL-(PDMAPS)4 assemblies broadened with asymmetric peaks, giving rise to curves with double peaks. After 24 h, DLS curves became symmetric with a single peak, and the Rh was about half that of the original assemblies. In the meantime, dispersed spherical micelles could be observed by TEM.

Barite is an abundant sulfate mineral in nature. Especially, the variety of morphologies of barite is often driven by the mixing of Ba-bearing hydrothermal fluid and sulfate-bearing seawater around hydrothermal chimneys. In order to better understand the factors affecting the morphology and precipitation mechanism(s) of barite in seafloor hydrothermal systems, we synthesized barite by a new method of in-situ mixing of BaCl2 and Na2SO4 solutions at 200 °C while varying Ba concentrations and ratios of Ba2+/SO42−, and at room temperature for comparison. The results show that barite synthesized by in-situ mixing of BaCl2 and Na2SO4 solutions at 200 °C forms a variety of morphologies, including rod-shaped, granular, plate-shaped, dendritic, X-shaped, and T-shaped morphologies, while room temperature barites display relatively simple, granular, or leaf-like morphologies. Thus, temperature affects barite morphology. Moreover, dendritic barite crystals only occurred at conditions where Ba2+ is in excess of SO42− at the experimental concentrations. The dendritic morphology of barite may be an important typomorphic feature of barite formed in high-temperature fluids directly mixing with excess Ba2+ relative to SO42−.

Purpose: A phenotype of COVID-19 ARDS patients with extremely low compliance and refractory hypercapnia was found in our ICU. In the context of limited number of ECMO machines, feasibility of a low-flow extracorporeal carbon dioxide removal (ECCO2R) based on the renal replacement therapy (RRT) platform in these patients was assessed.Methods: Single-center, prospective study. Refractory hypercapnia patients with COVID-19-associated ARDS were included and divided into the adjusted group and unadjusted group according to the level of PaCO2 after the application of the ECCO2R system. Ventilation parameters [tidal volume (VT), respiratory rate, and PEEP], platform pressure (Pplat) and driving pressure (DP), respiratory system compliance, arterial blood gases, and ECCO2R system characteristics were collected.Results: Twelve patients with refractory hypercapnia were enrolled, and the PaCO2 was 64.5 [56-88.75] mmHg. In the adjusted group, VT was significantly reduced from 5.90 ± 0.16 to 5.08 ± 0.43 ml/kg PBW; DP and Pplat were also significantly reduced from 23.5 ± 2.72 mmHg and 29.88 ± 3.04 mmHg to 18.5 ± 2.62 mmHg and 24.75 ± 3.41 mmHg, respectively. In the unadjusted group, PaCO2 decreased from 94 [86.25, 100.3] mmHg to 80 [67.50, 85.25] mmHg but with no significant difference, and the DP and Pplat were not decreased after weighing the pros and cons.Conclusions: A low-flow ECCO2R system based on the RRT platform enabled CO2 removal and could also decrease the DP and Pplat significantly, which provided a new way to treat these COVID-19 ARDS patients with refractory hypercapnia and extremely low compliance.Clinical Trial Registration:https://www.clinicaltrials.gov/, identifier NCT04340414.

Motion related artifact is a challenge for MRI, especially when imaging regions like the carotid artery where complex motion (abrupt and bulk motion) may occur. This study aims to develop a non-contact motion detection and correction system for carotid MRI using a markerless optical tracking system.The proposed markerless optical tracking system consisted of a cross-line laser, an MRI-compatible camera and plastic holders mounted inside the scanner bore. The neck motion of the subject can be captured by monitoring the change of the projected laser position in real-time. The system was used to correct both abrupt motion and bulk motion for carotid MRI. The abrupt motion (e.g. coughing) was compensated by discarding the corrupted k-space lines and re-estimating the missing lines using SPIRiT algorithm. The bulk motion was corrected by phase adjustment of k-space lines according to the measured 1D-translational bulk motion (along anterior-posterior direction) and optimized in-plane translation parameters. Ten volunteers underwent carotid MRI with real-time neck motion detection and retrospective motion correction. Artery sharpness, vessel wall thickness and overall image quality score were compared between the motion-corrupted image and motion-corrected images of different correction strategies.Both the abrupt motion and the bulk motion during carotid scanning were successfully detected and corrected. The results of ten volunteers demonstrated significant improvement in carotid artery sharpness, vessel wall thickness measurement, and overall image quality score using the proposed markerless optical tracking system and motion correction strategies.The proposed markerless structured light based motion detection and correction system can sensitively detect both abrupt and bulk motion during carotid MR scans. By correcting for both abrupt and bulk motion, vessel wall delineation was improved in carotid MR images, which could potentially facilitate carotid plaque identification and atherosclerosis diagnosis in the future.

Purpose To prospectively assess the diagnostic value of quick Sequential Organ Failure Assessment (qSOFA) and systemic inflammatory response syndrome (SIRS) scores for sepsis in ward patients with infections. Materials and methods Consecutive patients admitted with infection or developing infection during hospital stay were included. All variables for calculating qSOFA, SIRS, and SOFA scores were collected, and the maximum scores were determined until hospital discharge, death, or day 28, whichever occurred earlier. The primary outcome was sepsis at 28 days. Diagnostic and prognostic values were assessed using the area under the receiver operating characteristic curve (AUROC) with the conventional cutoff value of 2. Results Of 409 general ward patients, 146 patients and 371 patients met qSOFA and SIRS criteria, 229 patients developed sepsis. Although qSOFA score had a better overall diagnostic performance of sepsis (AUROC 0.75 vs. 0.69), it had a much lower sensitivity (53% vs. 98%) and higher specificity (87% vs. 18%) than SIRS score. In addition, qSOFA score had a better prognostic value than SIRS score (AUROC 0.86 vs. 0.67). Conclusions Neither SIRS score nor qSOFA score could serve as an ideal screening tool for early identification sepsis, whereas qSOFA score might help to identify patients with higher risk of poor clinical outcome. Trial registration clinicaltrials.gov Identifier: NCT 02930070.

Background: We aimed to evaluate the accuracy of quick Sequential (sepsis-related) Organ Failure Assessment (qSOFA) for the diagnosis of sepsis-3, and to analyze the prognosis of infected patients in wards over-diagnosed with qSOFA but missed by sepsis-3, and those missed by qSOFA but in accordance with sepsis-3 criteria. We also intended to validate the performance of qSOFA as one predictor of outcome in patients with suspicion of infection. Methods: We reviewed the medical records of 1716 adult patients with infection who were hospitalized from July 1 st , 2012 to June 30 th , 2014 in the Yuetan subdistrict of Beijing, China. Based on the sepsis-3 criteria and qSOFA score proposed by the Third International Consensus Definitions for Sepsis and Septic Shock, these patients were categorized into four groups: qSOFA(−)sepsis(−), qSOFA(+)sepsis(−), qSOFA(−) sepsis(+), and qSOFA(+)sepsis(+). Multivariate logistic regression analysis was used to determine the independent risk factors for in-hospital mortality. The area under the receiver operating characteristic curves (AUROCs) of the qSOFA(+) group were compared with the sepsis(+) group for in-hospital mortality, ICU admission, and invasive ventilation. Results: Among the 1,716 patients with infection, there were 935 patients (54.5%) with sepsis, and 640 patients (37.3%) with qSOFA ≥2. There were 610 patients in the qSOFA(−)sepsis(−) group, 171 in the qSOFA(+)sepsis(−) group, 466 in the qSOFA(−)sepsis(+) group, and 469 in the qSOFA(+)sepsis(+) group. In the logistic regression analysis, increasing age, bedridden status, and malignancy were all independent risk factors of hospital mortality. Sepsis and qSOFA ≥2 were also independent risk factors of hospital mortality, with an adjusted OR of 3.85 (95% CI: 2.70–5.50) and 13.92 (95% CI: 9.87–16.93) respectively. qSOFA had a sensitivity of 50.2% and a specificity of 78.1% for sepsis-3. The false-positive [qSOFA(+)sepsis(−)] group had 38 patients (22.2%) die during hospitalization, and an adjusted OR of 9.20 (95% CI: 4.86–17.38). In addition, the false-negative [qSOFA(−)sepsis(+)] group had a hospital mortality rate of 7.3% (34/466) and an adjusted OR of 2.59 (95% CI: 1.39–4.83). In comparison, patients meeting neither qSOFA nor sepsis criteria had the lowest hospital mortality [2.6% (16/610)], whereas patients with both qSOFA ≥2 and sepsis had the highest hospital mortality [56.5% (265/469)], with an adjusted OR of 42.02 (95% CI: 24.31–72.64). The discrimination of in-hospital mortality using qSOFA (AUROC, 0.846; 95% CI, 0.824–0.868) was greater compared with sepsis-3 criteria (AUROC, 0.834; 95% CI, 0.805–0.863; P Conclusions: In our analysis, the sensitivity(Se) of qSOFA for the diagnosis of sepsis was lower, and qSOFA score ≥2 might identify a group of patients at a higher risk of mortality, regardless of being septic or not.

Since the outbreak of COVID-19 in China at the end of 2019, the world has experienced a large-scale epidemic caused by the SARS-CoV-2. Epidemiological and clinical course of COVID-19 patients have been reported, but there have been few analyses about the characteristics, predictive risk factors and outcomes of critical patients. In this single-center retrospective case-control study, 90 adult inpatients hospitalized at Tongji Hospital (Wuhan, China) were included. Demographic, clinical, laboratory test and treatment data were obtained and compared between critical and non-critical patients. We found that compared with non-critical patients, the critical patients had higher SOFA score and qSOFA scores. Critical patients had lower lymphocyte and platelet count, elevated D-dimer, decreased fibrinogen, and elevated high-sensitivity C-reactive protein (hsCRP) and interleukin-6(IL-6). More critical patients received treatment including antibiotics, anticoagulation, corticosteroid and oxygen therapy than non-critical ones. Multivariable regression showed higher qSOFA score and elevation of IL-6 were related to critical patients. Antibiotic usage and anticoagulation were associated with decreased in-hospital mortality. And critical grouping contributed greatly to in-hospital death. Critical COVID-19 patients have a more severe clinical cours. qSOFA score and elevation of IL-6 are risk factors for critical condition. Non-critical grouping, positive antibiotic application and anticoagulation may be beneficial for patient survival.

Background: Mini-fluid challenge may predict fluid responsiveness and limit fluid overload. This study was designed to explore the minimal infusion volume in effectively predicting fluid responsiveness in septic shock patients.Methods: ICU septic shock patients with indwelling pulmonary artery catheter received five sequential intravenous boluses of 100 mL 4% gelatin. Cardiac output was measured with thermodilution before fluid challenge (baseline) and three minutes after each bolus. Fluid responsiveness (FR) was defined as an increase in CO greater than 10% after 500 mL fluid infusion. The smallest volume which can perform an effective fluid challenge was analyzed. Results: Forty-seven patients were included in this prospective study. After 500 mL volume expansion, thirty-six patients presented with FR (77%) and 11 patients were fluid nonresponders. A mini fluid of 100 mL colloid had a poor predictive value (AUC = 0.67, p > 0.05). The minimal volume required to predict FR in a mini fluid challenge was 200 mL. An increase in CO greater than 5.2% after 200 mL colloid infusion was able to predict FR with a sensitivity of 83.3% and specificity of 90.9%. The AUC under the ROC curve was 0.93 (95% CI: 0.84 – 1, p < 0.05). Conclusion: In septic shock patients, a minimal volume of 200 mL 4% gelatin could reliably detect fluid responders and nonresponders.Trial registration: ClinicalTrial.gov (NCT01941472). Registered on 13 September 2013.

Background: The complications of coronavirus disease 2019 (COVID-19) involved multiple organs or systems, especially in critically ill patients. We aim to investigate the neurological complications in critically ill patients with COVID-19. Methods: This retrospective single-center case series analyzed critically ill patients with COVID-19 at the intensive care unit of Tongji Hospital, Wuhan, China from February 5 to April 2, 2020. Demographic data, clinical and laboratory findings, comorbidities and treatments were collected and analyzed. Results: Among 86 patients with confirmed COVID-19, 54 patients (62.8%) were male, and the mean (SD) age was 66.6 (11.1) years. Overall, 65% patients presented with at least one neurological symptom. Twenty patients (23.3%) had symptoms involving the central nervous system, including delirium, cerebrovascular diseases and hypoxic-ischemic brain injury, while 6 patients (7%) had neuromuscular involvement. Seven of 86 patients exhibited new stroke and 6 (7%) cases were ischemic. A significantly higher prevalence of antiphospholipid antibodies was observed in patients with ischemic stroke than in those without stroke (83.3 vs. 26.9%, p < 0.05). Patients with ischemic stroke were more likely to have a higher myoglobulin level, and a lower hemoglobin level. Conclusions: The clinical spectrum of neurological complications in critically ill patients with COVID-19 was broad. Stroke, delirium and neuromuscular diseases are common neurological complications of COVID-19. Physicians should pay close attention to neurological complications in critically ill patients with COVID-19.

The etiologies of acute respiratory failure in patients with systemic rheumatic diseases (SRDs) requiring intensive care remain unknown. This study was undertaken to investigate the etiologies and outcomes.A medical records review study was performed of 259 adult SRDs patients with respiratory failure admitted to medical ICU across a 5-year period. The etiologies were classified as infection, SRD exacerbation, and undetermined. The factors associated with ICU mortality were identified with multivariate logistic regression analysis.The etiologies of respiratory failure included infection (n = 209, 80.7%), SRD exacerbation (n = 71, 27.4%), and undetermined (n = 21, 8.1%). The most common pathogen was Pneumocystis jirovecii (39.8%), followed by Aspergillus spp. (33.2%), and cytomegalovirus (23.2%). The ICU mortality rate was 59.8%. A high acute physiology and chronic health evaluation II score (OR 1.118, 95% CI 1.054 to 1.186, p 0.001), a PaOOpportunistic infections and SRD exacerbation were the most common etiologies of acute respiratory failure in patients with SRDs requiring ICU admission, with high ICU mortality. Development of a standard protocol for differential diagnosis in this population might help initiate definitive therapy and improve clinical outcome. Key Points • Infections, especially with opportunistic infections, were the leading cause of acute respiratory failure in critically ill rheumatology patients, with high mortality. • Severity of illness, certain types of rheumatic diseases, and opportunistic fungal infections were associated with increased mortality. • Using a comprehensive diagnostic workup might help to confirm the infective etiology and improve outcome.

Additional file 1: Table S1. Imputation of missing data for the calculation of SOFA or eSOFA score. eResults. Detailed Description of eSOFA/SOFA score of the 98 eSOFA+/Sepsis-3− patients. Table S2. Frequency of SOFA/eSOFA organ dysfunctions in patients meeting Sepsis-3 or eSOFA criteria. Figure S1. Frequency of SOFA or eSOFA organ dysfunctions in Sepsis-3+/eSOFA+ sepsis patients. Table S3. Risk models of in-hospital mortality.

Unhealable diabetic wounds and disabling scar formation in severe wounds need to be addressed with the help of multiple techniques. Here we put forward an idea to use exosomes loaded into a supporting scaffold to rebuild the vascular transportation system, which could solve hypoxia and infertility in these wounds. A highly efficient self-healing and biocompatible natural-based methylcellulose-chitosan hydrogel loaded with biological exosome nanoparticles has the appropriate strength and is made by an easy preparation process, and it eventually achieves the integrated structure needed for healing severe diabetic conditions. Hydrogels perform well in the cell proliferation and skin remodeling stages because of their three-dimensional porous structure, and self-healing and adhesion properties. Also, exosomes accumulated to an effective concentration for a period of time could induce proliferation, especially relating to vascular formation. After the overpass (vascular) has been constructed with the help of the base (hydrogel) and workers (exosomes), the society (skin) is reconstructed under a system of supply and regulation. The research results indicate that these novel complex hydrogels loaded with exosomes provide wide prospects for the healing of severe wounds.

A novel CNC-g-P(AzoC6MA-co-DMAEMA) fluorescent nanosensor was synthesized by the atom transfer radical copolymerization (ATRP) reaction of AzoC6MA and DMAEMA with cellulose nanocrystals (CNCs) modified with 2-bromoisobutyryl groups (CNC-Br) as the initiators. The characterization of environmentally sensitive CNC-g-P(AzoC6MA-co-DMAEMA) fluorescent nanosensor was studied, and its responses to ultraviolet (UV) light, temperature and pH were investigated. Under irradiation of UV light, the CNC-g-P(AzoC6MA-co-DMAEMA) fluorescent nanosensor exhibited isomerization of molecular structures of azobenzene groups and reversible transformation of fluorescence intensity. Due to the temperature- and pH-responsive properties of P(AzoC6MA-co-DMAEMA) side chains in the graft copolymers, the microenvironment of azobenzene groups in the fluorescent nanosensors could be changed through adjusting the external temperature or pH, which led to a reversible change in the fluorescence intensity of the nanosensors. This type of simple, cheap, dispersible and sensitive fluorescent nanosensor has potential advantages of in situ detection and monitoring of temperature or pH in organisms or water.

Background Pharmacologic stress ulcer prophylaxis (SUP) is recommended in critically ill patients with high risk of stress-related gastrointestinal (GI) bleeding. However, as to patients receiving enteral feeding, the preventive effect of SUP is not well-known. Therefore, we performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of pharmacologic SUP in enterally fed patients on stress-related GI bleeding and other clinical outcomes. Methods We searched PubMed, Embase, and the Cochrane database from inception through 30 Sep 2017. Eligible trials were RCTs comparing pharmacologic SUP to either placebo or no prophylaxis in enterally fed patients in the ICU. Results were expressed as risk ratio (RR) and mean difference (MD) with accompanying 95% confidence interval (CI). Heterogeneity, subgroup analysis, sensitivity analysis and publication bias were explored. Results Seven studies (n = 889 patients) were included. There was no statistically significant difference in GI bleeding (RR 0.80; 95% CI, 0.49 to 1.31, p = 0.37) between groups. This finding was confirmed by further subgroup analyses and sensitivity analysis. In addition, SUP had no effect on overall mortality (RR 1.21; 95% CI, 0.94 to 1.56, p = 0.14), Clostridium difficile infection (RR 0.89; 95% CI, 0.25 to 3.19, p = 0.86), length of stay in the ICU (MD 0.04 days; 95% CI, −0.79 to 0.87, p = 0.92), duration of mechanical ventilation (MD −0.38 days; 95% CI, −1.48 to 0.72, p = 0.50), but was associated with an increased risk of hospital-acquired pneumonia (RR 1.53; 95% CI, 1.04 to 2.27; p = 0.03). Conclusions Our results suggested that in patients receiving enteral feeding, pharmacologic SUP is not beneficial and combined interventions may even increase the risk of nosocomial pneumonia. Electronic supplementary material The online version of this article (doi:10.1186/s13054-017-1937-1) contains supplementary material, which is available to authorized users.

Purpose To evaluate whether the changes of central venous oxygen saturation (Scvo 2 ) after fluid challenge can define fluid responsiveness in patients with septic shock. Methods In this prospective observational study, septic shock patients with invasive cardiac output monitoring requiring fluid challenge were included. Cardiac index (CI) and Scvo 2 were measured before and after fluid challenges. The changes of CI (ΔCI) and the changes of Scvo 2 (ΔScvo 2 ) were calculated and analyzed using Pearson correlation. Receiver operating characteristics curve (ROC) analysis was used to classify fluid responders and nonresponders. Area under ROC was calculated. Results Forty patients were included and 18 patients (45%) were fluid responders. In the responders, CI increased from 3.4±1.1 to 4.4±1.0 L min −1 m −2 and Scvo 2 from 69.6%±9.8% to 77.1%±8.9% (both P 2 changed (4.1±1.3 vs 4.1±1.3 L min −1 m −2 , 71.0%±13.8% vs 70.6%±14.1%, both P >.05). The correlation between ΔScvo 2 and ΔCI was significant ( r =0.702, P 2 to define fluid responsiveness was 0.88 (95% confidence interval [95% CI], 0.76-0.99). A ΔScvo 2 threshold value of 5.0% discriminated responders from nonresponders with sensitivity of 0.78 (95% CI, 0.52-0.93) and specificity of 0.95 (95% CI, 0.75-1.00). Conclusions The changes of Scvo 2 correlate with the changes of CI, and the changes of Scvo 2 define fluid responsiveness in patients with septic shock.

A glucose-, thermo-, and pH-triple responsive copolymer, poly(2-phenylboronic esters-1,3-dioxane-5-ethyl) methylacrylate-b-poly(2-(N,N-dimethylamino)ethyl methacrylate) (PPBDEMA-b-PDMAEMA), was synthesized through atom transfer radical polymerization (ATRP). Benefiting from its amphiphilicity, PPBDEMA-b-PDMAEMA could self-assemble in water into micelles with the PPBDEMA core and the PDMAEMA shell. Glucose would react with PPBDEMA, leading to the expansion of the micelles. Because of the thermo-responsive PDMAEMA segment, increasing temperature would cause the PDMAEMA shell to shrink and the micelles to aggregate. Both PPBDEMA and PDMAEMA segments were found to have pH-responsive properties, but PDMAEMA responded faster than PPBDEMA upon pH stimulus. When the pH value was high (>8), the original copolymer micelles would disassemble and new micelles with the PPBDEMA shell and the PDMAEMA core would form after 48 h. PPBDEMA-b-PDMAEMA copolymer micelles could be used as smart carriers to achieve the multi-controlled release of insulin and Nile red fluorescent dye molecules by adjusting the temperature, the pH value, and the glucose concentration. The release rate of insulin from the micelles at high glucose concentrations was much faster than that at lower glucose concentrations at the physiological pH value and could be further accelerated by heating. Meanwhile, increasing the temperature, the pH value, and the glucose concentration would increase the release rate of Nile red from the micelles.

Background: The Space Glucose Control (SGC) system is a computer-assisted device combining infusion pumps with the enhanced Model Predictive Control algorithm to achieve the target blood glucose (BG) level safely. The objective of this study was to evaluate the efficacy and safety of glycemic control by SGC with customized BG target range of 5.8–8.9 mmol/L in the critically ill patients. Methods: It is a randomized controlled trial of seventy critically ill patients with mechanical ventilation and hyperglycemia (BG ≥ 9.0 mmol/L). Thirty-six patients in the SGC group and 34 in the routine glucose management group were observed for three consecutive days. Target BG for both groups was 5.8–8.9 mmol/L. The primary outcome was the percentage time in the target range. Results: The percentage time within BG target range in the SGC group (69 ± 15%) was significantly higher than in the routine management group (52 ± 24%; P < 0.01). No measurement was ≤2.2 mmol/L, and there was only one episode of hypoglycemia (2.3–3.3 mmol/L) in each group. The average BG was significantly lower in the SGC group (7.8 ± 0.7 mmol/L) than in the routine management group (9.1 ± 1.6 mmol/L, P < 0.001). Target BG level was reached earlier in the SGC group than routine management group (2.5 ± 2.9 vs. 12.1 ± 15.3 h, P = 0.001). However, the SGC group performed worse for daily insulin requirement (59.8 ± 39.3 vs. 28.4 ± 36.7 U, P = 0.001) and sampling interval (2.0 ± 0.5 vs. 3.7 ± 0.5 h, P < 0.001) than the routine management group did. Multiple linear regression showed that the intervention group remained a significant individual predictor (P < 0.001) of the percentage time in target range. Conclusions: The SGC system, with a BG target of 5.8–8.9 mmol/L, resulted in effective and reliable glycemic control with few hypoglycemic episodes in critically ill patients with mechanical ventilation and hyperglycemia. However, the workload was increased. Trial Registration: http://www.clinicaltrials.gov, NCT 02491346; https://www.clinicaltrials.gov/ct2/show/NCT02491346?term=NCT02491346&cond=Hyperglycemia&cntry1=ES%3ACN&rank=1.

Background The US Centers for Disease Control and Prevention (CDC) recently released simplified eSOFA organ dysfunction criteria of Adult Sepsis Event for sepsis surveillance in the US. Our study aimed to compare the prevalence, characteristics, and outcomes of sepsis patients identified by eSOFA criteria versus Sequential Organ Failure Assessment (SOFA) Score (Sepsis-3) and assess the external validity of eSOFA criteria in China. Methods We conducted a retrospective cohort study of adult residents of Yuetan Subdistrict, Beijing, China, who were hospitalized from July 1, 2012 to June 30, 2014. Among patients with infection, sepsis was identified if there was a concurrent rise in SOFA score by 2 or more points (Sepsis-3) or the presence of 1 or more eSOFA criteria: vasopressor initiation, mechanical ventilation initiation, doubling in creatinine, doubling in bilirubin to 2.0 mg/dL or above, 50% or greater decrease in platelet count to less than 100 cells/μL, or lactate equal to or above 2.0 mmol/L. Areas under the receiver operating characteristic curves (AUROCs) for in-hospital mortality were compared between sepsis patients detected by the two criteria, adjusting for baseline characteristics. Results Of 1716 hospitalized patients with infection, 935 (54.5%) met Sepsis-3 criteria, 573 (33.4%) met eSOFA criteria, while 475 (27.7%) met both criteria. Demographic and clinical characteristics of sepsis patients meeting Sepsis-3 or eSOFA criteria were similar. In-hospital mortality was higher with eSOFA criteria versus Sepsis-3 (46.6% vs. 32.0%, p p p = 0.097). The predicted probability for in-hospital mortality was higher with eSOFA criteria versus Sepsis-3 (AUROC 0.830 vs. 0.795, p = 0.001) adjusting for baseline characteristics. Conclusions The CDC Adult Sepsis Event’s eSOFA criteria identify a smaller, more severely ill cohort of sepsis patients with similar demographic and clinical characteristics as the more complex Sepsis-3 SOFA score. These results suggest similar performance of eSOFA criteria across diverse populations, with low sensitivity and high specificity for the diagnosis of Sepsis-3.

Compared to conventional chemotherapy with subcutaneous and intravenous injection, injection of self-healing hydrogel drug-delivery system to tumor site brings less toxicity for normal tissues, but also better specificity for tumor cells on account of spontaneous repair and better retention. More importantly, it is essential to introduce multifunctional nanomaterials into self-healing hydrogel loading chemotherapeutic drugs to significantly enhance tumor treatment effect. Therefore, Rhodamin B isothiocyanate (RBITC)-labeled mesoporous silica nanospheres with Mn-Zn Ferrite (Mn0.6Zn0.4Fe2O4) nanoparticle core (MMSN-RBITC) are prepared and well-dispersed into hydrogel system. The generated heat under alternate magnetic field induces hyperthermia effect for magnetothermal therapy, which could also promote the sensibilization of chemotherapy. Hydroxyl radicals are produced via Fenton-like catalyzation after the cellular uptake of MMSN-RBITCs further promoting the cell apoptosis via chemodynamic therapy. The nanoplatform also presents excellent T2-weighted magnetic resonance imaging contrast enhancement. As a result, the hydrogel system is effectively enhanced and enriched via the introduction of the nanospheres. In vitro and in vivo results indicate that this strategy of self-healing hydrogel loading DOX and MMSN-RBITC can achieve tumor diagnosis and efficiently synergistic magnetothermal-chemo-chemodynamic therapy. This strategy could inspire people to construct more promising platforms combining self-healing hydrogel with multifunctional nanomaterials for more efficient cancer treatment with versatile therapeutic methods.

Background Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure. Methods This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency. Results Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P < 0.001). Although microaspiration frequencies were high, they did not differ between groups. Conclusion For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.

Background:Several studies showed two main clinical phenotypes of antiphospholipid syndrome which could be independent, but only a few data contrast features between these two groups.Objectives:To investigate whether obstetric and thrombotic manifestations of APS are independent subtypes.Methods:This was a single center prospective study from the PUMCH database of primary antiphospholipid syndrome followed for over 4years. Comparing demographic data, laboratory tests, pregnancy morbidity and thrombotic events during follow-up between IoAPS (isolated obstetric APS) and ItAPS (isolated thrombotic APS).Results:A total of 244 patients was registered in PUMCH primary APS cohorts, 157(64.34%) were female patients. In female patients, 44(28.03%) were diagnosed with IoAPS, 42(26.75%) were ItAPS. Demography showed patients in ItAPS group were older than IoAPS group (40 vs 33, pConclusion:IoAPS and ItAPS shared similar antibody profile, but presented isolated clinical complications, different demographic features and maintained independent manifestation during follow-up, indicating the underlying pathogeneses are different.References:[1]Meroni P L, Borghi M O, Grossi C, et al. Obstetric and vascular antiphospholipid syndrome: same antibodies but different diseases?[J]. Nat Rev Rheumatol, 2018, 14(7): 433-440Table1.Demographic characteristicsIoAPS(n=44)ItAPS(n=42)P-valueAge, years, Median (Q1-Q3)33 (30.00, 36.00)40(33.75, 55.25).00B.M.I. Median (Q1-Q3)22.86 (20.70,24.45)23.52 (21.44, 27.70).10Flow-up time, month,Median (Q1-Q3)48.50 (36.00,77.00)49.50 (23.00,103.75).44Smoke (n%)1(2.27)0(0)1.00Cardiovascular risk factors (n%)3 (6.82)14 (33.33).00Coronary heart disease0(0)2(4.76).24Hypertension1(2.27)5(11.90).11Obesity2(4.55)9(21.43).03Diabetes mellitus0(0)0(0)Complications (n%)16 (36.36)30 (71.43).00Kidney diseases2(4.55)3(7.14).67Thrombocytopenia9(20.45)20(47.62).01Neurological Disorders1(2.27)10(23.81).00Stroke0(0)8(19.05).00Non stroke CNS manifestations1(2.27)2(4.76).61Valvular heart diseases4(9.09)2(4.76).68Failed pregnancy during follow-up (%)116/154(75.32)5/90(5.56).00Thrombosis during follow-up (n%)0(0)4(9.52).05Table 2.Laboratory testsIoAPS(n=44)ItAPS(n=42)P-valueAntibody categoriesTriple positive (n%)ACL+β2GPI+LA11(25.00)15(35.71).35Double positive (n%)7(15.90)11(26.19).29LA+ACL0(0)1(2.38).49LA+anti-β2GPI2(4.55)3(7.14).67ACL+anti-β2GPI5(11.36)7(16.67).55Single positive (n%)26(59.10)16(38.10).04ACL1(2.27)1(2.38)1.00anti-β2GPI23(52.27)10(23.81).01LA2(4.55)5(11.90).26Negative after treatment4(9.09)1(2.38).36ESR10(6, 27)9(4, 16).06CRP1.03(0.56, 3.85)1.11(0.43, 3.18).63HCY9.9(8.10, 12.10)11.5 (9.30, 14.65).04*aCL: anticardiolipin antibodies; anti-β2-GPI: anti-β2 glycoprotein I antibodies; LA: lupus anticoagulant; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; HCY: homocysteine.Acknowledgments:The authors thank Department of Rheumatology in Peking Union Medical College Hospital for support with statistics.Disclosure of Interests:None declared

Coagulopathy in Critical Illness with Covid-19 The authors describe a 69-year-old man with Covid-19 diagnosed in January 2020 in Wuhan, China, along with two other critically ill patients with Covi...

This report evaluates the effectiveness of corporate social responsibility and contemporary community expectations. It analyses the definition of corporate social responsibility and the community expectations of CSR. The findings indicate that some company corporate social responsibility policy meet the community expectations. For instance, Westpac bank acts well in gender equality and scholar and Telstra has good performance in charity. However, there remain conflicts between CSR and community expectations. Optus collects customer information and leakage with careless conflicting legal element. Clean Tech provides the environmental service which is opposite of economic element in CSR. This report proposes some recommendations for company to keep balance for both CSR and community expectations.

Background Serum procalcitonin (PCT) concentration is used to guide antibiotic decisions in choice, timing, and duration of anti-infection therapy to avoid antibiotic overuse. Thus, we performed a systematic review and meta-analysis to seek evidence of different PCT-guided antimicrobial strategies for critically ill patients in terms of predefined clinical outcomes. Methods We searched for relevant studies in PubMed, Embase, Web of Knowledge, and the Cochrane Library up to 25 February 2017. Randomized controlled trials (RCTs) were included if they reported data on any of the predefined outcomes in adult ICU patients managed with a PCT-guided algorithm or according to standard care. Results were expressed as risk ratio (RR) or mean difference (MD) with accompanying 95% confidence interval (CI). Data synthesis We included 13 trials enrolling 5136 patients. These studies used PCT in three clinical strategies: initiation, discontinuation, or combination of antibiotic initiation and discontinuation strategies. Pooled analysis showed a PCT-guided antibiotic discontinuation strategy had fewer total days with antibiotics (MD − 1.66 days; 95% CI − 2.36 to − 0.96 days), longer antibiotic-free days (MD 2.26 days; 95% CI 1.40–3.12 days), and lower short-term mortality (RR 0.87; 95% CI 0.76–0.98), without adversely affecting other outcomes. Only few studies reported data on other PCT-guided strategies for antibiotic therapies, and the pooled results showed no benefit in the predefined outcomes. Conclusions Our meta-analysis produced evidence that among all the PCT-based strategies, only using PCT for antibiotic discontinuation can reduce both antibiotic exposure and short-term mortality in a critical care setting. Electronic supplementary material The online version of this article (10.1186/s13613-017-0338-6) contains supplementary material, which is available to authorized users.

Self-healing polymeric hydrogels have the capability to recover their structures and functionalities upon injury, which are extremely attractive in emerging biomedical applications. Self-healing hydrogels with multifunctional properties as an important biomaterial class have been widely used in delivering cell, gene, drug and so on. Except high water content similar with extracellular matrix (ECM), hydrogels also need meet biocompatible scaffold requirements such as degradable, tough, injectable and good adhesiveness, and are developing more functional and smarter. Based on the significant studies of the biomedical scaffold in recent years, we review the widely used mechanism of the self-healing hydrogels, with focus on the design of the biocompatible scaffold and their relevant biomedical applications. The prospective regarding of the future potential development in functional and smart aspects is also delivered.

Background Pneumocystis jiroveci pneumonia (PJP) in non-HIV patients is still a challenge for intensivists. The aim of our study was to evaluate mortality predictors of PJP patients requiring Intensive care unit (ICU) admission. Methods Retrospectively review medical records of patients with diagnosis of PJP admitted to four ICUs of two academic medical centers from October 2012 to October 2015. Results Eighty-two patients were enrolled in the study. Overall hospital mortality was 75.6 %. Compared with survivors, the non-survivors had older age (55 ± 16 vs. 45 ± 17, p = 0.014), higher APACHE II score (20 ± 5 vs. 17 ± 5, p = 0.01), lower white blood cell count (7.68 ± 3.44 vs. 10.48 ± 4.62, p = 0.005), less fever (80.6%vs. 100 %, p = 0.033), more hypotension (58.1 % vs. 20 %, p = 0.003), more pneumomediastinum (29 % vs. 5 %, p = 0.027). Logistic regression analysis demonstrated that age [odds ratio (OR)1.051; 95 % CI 1.007-1.097; p = 0.022], white blood cell count [OR 0.802; 95 % CI 0.670-0.960; p = 0.016], and pneumomediastinum [OR 16.514; 95 % CI 1.330-205.027; p = 0.029] were independently associated with hospital mortality. Conclusions Mortality rate for non-HIV PJP patients requiring ICU admission was still high. Poor prognostic factors included age, white blood cell count and pneumomediastinum. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-1855-x) contains supplementary material, which is available to authorized users.

Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure.This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency.Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P0.001). Although microaspiration frequencies were high, they did not differ between groups.For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.