Ilias I. Siempos

Dr. Ilias I. Siempos


Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2015 in The Lancet Respiratory Medicine
Verified
Journal Article
Closed access
ISIlias I. Siempos
Ilias I. Siempos
TNTheodora K Ntaidou
Theodora K Ntaidou
FFFilippos T Filippidis
Filippos T Filippidis
ACAugustine M K Choi
Augustine M K Choi

25 March 2021 in Critical Care
Verified
Journal Article
Open access
PDF file
EPEleni Papoutsi
Eleni Papoutsi
VGVassilis G. Giannakoulis
Vassilis G. Giannakoulis
EXEleni Xourgia
Eleni Xourgia
CRChristina Routsi
Christina Routsi
AKAnastasia Kotanidou
Anastasia Kotanidou
ISIlias I. Siempos
Ilias I. Siempos
Background: Although several international guidelines recommend early over late intubation of patients with severe coronavirus disease 2019 (COVID-19), this issue is still controversial. We aimed to investigate the effect (if any) of timing of intubation on clinical outcomes of critically ill patients with COVID-19 by carrying out a systematic review and meta-analysis. Methods: PubMed and Scopus were systematically searched, while references and preprint servers were explored, for relevant articles up to December 26, 2020, to identify studies which reported on mortality and/or morbidity of patients with COVID-19 undergoing early versus late intubation. “Early” was defined as intubation within 24 h from intensive care unit (ICU) admission, while “late” as intubation at any time after 24 h of ICU admission. All-cause mortality and duration of mechanical ventilation (MV) were the primary outcomes of the meta-analysis. Pooled risk ratio (RR), pooled mean difference (MD) and 95% confidence intervals (CI) were calculated using a random effects model. The meta-analysis was registered with PROSPERO (CRD42020222147). Results: A total of 12 studies, involving 8944 critically ill patients with COVID-19, were included. There was no statistically detectable difference on all-cause mortality between patients undergoing early versus late intubation (3981 deaths; 45.4% versus 39.1%; RR 1.07, 95% CI 0.99–1.15, p = 0.08). This was also the case for duration of MV (1892 patients; MD − 0.58 days, 95% CI − 3.06 to 1.89 days, p = 0.65). In a sensitivity analysis using an alternate definition of early/late intubation, intubation without versus with a prior trial of high-flow nasal cannula or noninvasive mechanical ventilation was still not associated with a statistically detectable difference on all-cause mortality (1128 deaths; 48.9% versus 42.5%; RR 1.11, 95% CI 0.99–1.25, p = 0.08). Conclusions: The synthesized evidence suggests that timing of intubation may have no effect on mortality and morbidity of critically ill patients with COVID-19. These results might justify a wait-and-see approach, which may lead to fewer intubations. Relevant guidelines may therefore need to be updated.

1 November 2020 in JCO Global Oncology
Verified
Journal Article
Open access
VGVassilis G. Giannakoulis
Vassilis G. Giannakoulis
EPEleni Papoutsi
Eleni Papoutsi
ISIlias I. Siempos
Ilias I. Siempos
PURPOSE: Whether cancer is associated with worse prognosis among patients with COVID-19 is unknown. We aimed to quantify the effect (if any) of the presence as opposed to absence of cancer on important clinical outcomes of patients with COVID-19 by carrying out a systematic review and meta-analysis. METHODS: We systematically searched PubMed, medRxiv, COVID-19 Open Research Dataset (CORD-19), and references of relevant articles up to April 27, 2020, to identify observational studies comparing patients with versus without cancer infected with COVID-19 and to report on mortality and/or need for admission to the intensive care unit (ICU). We calculated pooled risk ratios (RR) and 95% CIs with a random-effects model. The meta-analysis was registered with PROSPERO (CRD42020181531). RESULTS: A total of 32 studies involving 46,499 patients (1,776 patients with cancer) with COVID-19 from Asia, Europe, and the United States were included. All-cause mortality was higher in patients with versus those without cancer (2,034 deaths; RR, 1.66; 95% CI, 1.33 to 2.07; P < .0001; 8 studies with 37,807 patients). The need for ICU admission was also more likely in patients with versus without cancer (3,220 events; RR, 1.56; 95% CI, 1.31 to 1.87; P < .0001; 26 studies with 15,375 patients). However, in a prespecified subgroup analysis of patients > 65 years of age, all-cause mortality was comparable between those with versus without cancer (915 deaths; RR, 1.06; 95% CI, 0.79 to 1.41; P = .71; 8 studies with 5,438 patients). CONCLUSION: The synthesized evidence suggests that cancer is associated with worse clinical outcomes among patients with COVID-19. However, elderly patients with cancer may not be at increased risk of death when infected with COVID-19. These findings may inform discussions of clinicians with patients about prognosis and may guide health policies.

26 March 2017 in Critical Care
Verified
Journal Article
Open access
PDF file
EFEli J. Finkelsztein
Eli J. Finkelsztein
DJDaniel S. Jones
Daniel S. Jones
KMKevin C. Ma
Kevin C. Ma
MPMaria A. Pabón
Maria A. Pabón
TDTatiana Delgado
Tatiana Delgado
ISIlias I. Siempos
Ilias I. Siempos
The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) Task Force recently introduced a new clinical score termed quick Sequential (Sepsis-related) Organ Failure Assessment (qSOFA) for identification of patients at risk of sepsis outside the intensive care unit (ICU). We attempted to compare the discriminatory capacity of the qSOFA versus the Systemic Inflammatory Response Syndrome (SIRS) score for predicting mortality, ICU-free days, and organ dysfunction-free days in patients with suspicion of infection outside the ICU. The Weill Cornell Medicine Registry and Biobank of Critically Ill Patients is an ongoing cohort of critically ill patients, for whom biological samples and clinical information (including vital signs before and during ICU hospitalization) are prospectively collected. Using such information, qSOFA and SIRS scores outside the ICU (specifically, within 8 hours before ICU admission) were calculated. This study population was therefore comprised of patients in the emergency department or the hospital wards who had suspected infection, were subsequently admitted to the medical ICU and were included in the Registry and Biobank. One hundred fifty-two patients (67% from the emergency department) were included in this study. Sixty-seven percent had positive cultures and 19% died in the hospital. Discrimination of in-hospital mortality using qSOFA [area under the receiver operating characteristic curve (AUC), 0.74; 95% confidence intervals (CI), 0.66–0.81] was significantly greater compared with SIRS criteria (AUC, 0.59; 95% CI, 0.51–0.67; p = 0.03). The qSOFA performed better than SIRS regarding discrimination for ICU-free days (p = 0.04), but not for ventilator-free days (p = 0.19), any organ dysfunction-free days (p = 0.13), or renal dysfunction-free days (p = 0.17). In patients with suspected infection who eventually required admission to the ICU, qSOFA calculated before their ICU admission had greater accuracy than SIRS for predicting mortality and ICU-free days. However, it may be less clear whether qSOFA is also better than SIRS criteria for predicting ventilator free-days and organ dysfunction-free days. These findings may help clinicians gain further insight into the usefulness of qSOFA.

1 March 2010 in Critical Care Medicine
Verified
Journal Article
Closed access
ISIlias I. Siempos
Ilias I. Siempos
TNTheodora K. Ntaidou
Theodora K. Ntaidou
MFMatthew E. Falagas
Matthew E. Falagas
Previous reviews showed no benefit for the administration of probiotics in critically ill patients, but they did not focus on ventilator-associated pneumonia. Meta-analysis of randomized controlled trials comparing probiotics and control in patients undergoing mechanical ventilation and reporting on incidence of ventilator-associated pneumonia. PubMed, Scopus, Current Contents, Cochrane Central Register of Controlled Trials, and reference lists were searched. Weighted mean differences, pooled odds ratios, and 95% confidence intervals were calculated, implementing both the Mantel-Haenszel fixed effect and the DerSimonian-Laird random effects model. Five randomized controlled trials were included. Administration of probiotics, compared with control, was beneficial in terms of incidence of ventilator-associated pneumonia (689 patients; fixed effect model: odds ratio, 0.61; 95% confidence interval, 0.41–0.91; random effects model: odds ratio, 0.55, 95% confidence interval, 0.31–0.98), length of intensive care unit stay (fixed effect model: weighted mean difference, –0.99 days; 95% confidence interval, –1.37–−0.61), and colonization of the respiratory tract with Pseudomonas aeruginosa (odds ratio, 0.35; 95% confidence interval, 0.13–0.93). However, no difference was revealed between comparators regarding intensive care unit mortality (odds ratio, 0.75; 95% confidence interval, 0.47–1.21), in-hospital mortality (odds ratio, 0.75; 95% confidence interval, 0.46–1.24), duration of mechanical ventilation (weighted mean difference, –0.01 days; 95% confidence interval, –0.31–−0.29), and diarrhea (odds ratio, 0.61; 95% confidence interval, 0.28–1.34). Administration of probiotics is associated with lower incidence of ventilator-associated pneumonia than control. Given the increasing antimicrobial resistance, this promising strategy deserves consideration in future studies, which should have active surveillance for probiotic-induced diseases.

15 September 2017 in American Journal of Respiratory and Critical Care Medicine
Verified
Journal Article
Closed access
SLSeonmin Lee
Seonmin Lee
KNKiichi Nakahira
Kiichi Nakahira
Jesmond DalliJesmond Dalli
Jesmond Dalli
ISIlias I. Siempos
Ilias I. Siempos
PNPaul C. Norris
Paul C. Norris
ACAugustine M. K. Choi
Augustine M. K. Choi
Rationale: Sepsis, a life-threatening organ dysfunction caused by a dysregulated host response to infection, is a major public health concern with high mortality and morbidity. Although inflammatory responses triggered by infection are crucial for host defense against invading microbes, the excessive inflammation often causes tissue damage leading to organ dysfunction. Resolution of inflammation, an active immune process mediated by endogenous lipid mediators (LMs), is important to maintain host homeostasis. Objectives: We sought to determine the role of the nucleotide-binding domain, leucine-rich repeat–containing receptor, pyrin domain–containing-3 (NLRP3) inflammasome in polymicrobial sepsis and regulation of LM biosynthesis. Methods: We performed cecal ligation and puncture (CLP) using mice lacking NLRP3 inflammasome-associated molecules to assess mortality. Inflammation was evaluated by using biologic fluids including plasma, bronchoalveolar, and peritoneal lavage fluid. Local acting LMs in peritoneal lavage fluid from polymicrobacterial septic mice were assessed by mass spectrometry–based metabololipidomics. Measurements and Main Results: Genetic deficiency of NLRP3 inhibited inflammatory responses and enhanced survival of CLP-induced septic mice. NLRP3 deficiency reduced proinflammatory LMs and increased proresolving LM, lipoxin B4 (LXB4) in septic mice, and in macrophages stimulated with LPS and ATP. Activation of the NLRP3 inflammasome induced caspase-7 cleavage and pyroptosis. Caspase-7 deficiency similarly reduced inflammation and mortality in CLP-induced sepsis, and increased LXB4 production in vivo and in vitro. Exogenous application of LXB4 reduced inflammation, pyroptosis, and mortality of mice after CLP. Conclusions: Genetic deficiency of NLRP3 promoted resolution of inflammation in polymicrobial sepsis by relieving caspase-7–dependent repression of LXB4 biosynthesis, and increased survival potentially via LXB4 production and inhibition of proinflammatory cytokines.