Nikolaos Machairas

Dr. Nikolaos Machairas

National and Kapodistrian University of Athens, Athens, Greece
orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

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

Representative Publications

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23 April 2020 in Nutrition and Cancer
Verified
Journal Article
Closed access
Irene LidorikiIrene Lidoriki
Irene Lidoriki
DSDimitrios Schizas
Dimitrios Schizas
MFMaximos Frountzas
Maximos Frountzas
Nikolaos MachairasNikolaos Machairas
Nikolaos Machairas
APAnastasia Prodromidou
Anastasia Prodromidou
TLTheodoros Liakakos
Theodoros Liakakos
Oncologic patients often suffer from malnutrition which in turn, might have negative impact on treatment outcomes. The Geriatric Nutritional Risk Index (GNRI), as an index of impaired nutritional status, has emerged as a significant prognostic factor for short-and long-term outcomes in cancer patients. The aim of the current systematic review is to determine whether the GNRI is an independent prognostic factor of postoperative complications and survival in cancer patients. A systematic search was conducted to identify studies, published from 2005 to 2019, which assessed associations between GNRI and short- and long-term outcomes in cancer patients. Eighteen studies fulfilled the eligibility criteria and were included in the analysis. Low scores of GNRI were associated with increased risk for developing postoperative complications and impaired survival of cancer patients in most studies. Our findings support the use of the GNRI in the clinical practice, since it is a simple and reliable tool for assessing nutritional status in oncologic patients. More prospective, multi-centered studies are warranted to confirm the current results, as well as the role of nutritional support in improving the prognosis of cancer patients.

3 September 2020 in Annals of Surgery
Verified
Journal Article
Closed access
DRDimitri A. Md Raptis
Dimitri A. Md Raptis
PSPatricia Md Sánchez-Velázquez
Patricia Md Sánchez-Velázquez
Nikolaos MachairasNikolaos Machairas
Nikolaos Machairas
ASAlain Sauvanet
Alain Sauvanet
ALAlexandra Rueda de Leon
Alexandra Rueda de Leon
GFGiuseppe Kito Ms Fusai
Giuseppe Kito Ms Fusai
Objective: The aim of this study was to establish clinically relevant outcome benchmark values using criteria for pancreatoduodenectomy (PD) with portomesenteric venous resection (PVR) from a low-risk cohort managed in high-volume centers. Summary Background Data: PD with PVR is regarded as the standard of care in patients with cancer involvement of the portomesenteric venous axis. There are, however, no benchmark outcome indicators for this population which hampers comparisons of patients undergoing PD with and without PVR resection. Methods: This multicenter study analyzed patients undergoing PD with any type of PVR in 23 high-volume centers from 2009 to 2018. Nineteen outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of the centers (NCT04053998). Results: Out of 1462 patients with PD and PVR, 840 (58%) formed the benchmark cohort, with a mean age was 64 (SD11) years, 413 (49%) were females. Benchmark cutoffs, among others, were calculated as follows: Clinically relevant pancreatic fistula rate (International Study Group of Pancreatic Surgery): ≤14%; in-hospital mortality rate: ≤4%; major complication rate Grade≥3 and the CCI up to 6 months postoperatively: ≤36% and ≤26, respectively; portal vein thrombosis rate: ≤14% and 5-year survival for patients with pancreatic ductal adenocarcinoma: ≥9%. Conclusion: These novel benchmark cutoffs targeting surgical performance, morbidity, mortality, and oncological parameters show relatively inferior results in patients undergoing vascular resection because of involvement of the portomesenteric venous axis. These benchmark values however can be used to conclusively assess the results of different centers or surgeons operating on this high-risk group.

27 August 2018 in In Vivo
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Journal Article
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ANAlkippi Nitsa
Alkippi Nitsa
MTMarina Toutouza
Marina Toutouza
Nikolaos MachairasNikolaos Machairas
Nikolaos Machairas
AMAnargyros Mariolis
Anargyros Mariolis
APAnastassios Philippou
Anastassios Philippou
Michael KoutsilierisMichael Koutsilieris
Michael Koutsilieris
Cardiovascular disease is the prevalent cause of morbidity and mortality in the world, affecting many millions of individuals every year. Atherosclerosis, a chronic inflammatory condition that involves different cell types, several cytokines and adhesion molecules, is the underlying cause of cardiovascular disease. Vitamin D is known to control skeletal patho/physiology, regulating calcium and phosphorus and bone remodeling along with other calcium-regulating hormones. However, several active metabolites of vitamin D can exert both direct action, mainly via vitamin D3 receptor trans-activation and indirect actions on several other tissues by an endocrine, autocrine and paracrine manners. With regard to cardiovascular disease, vitamin D deficiency has been associated with activation of the pro-inflammatory mechanism, promoting atherogenesis. There are several large-scale clinical studies, as well as meta-analyses that support this finding. However, it is still unclear whether the plasma 25-hydroxyvitamin D level can be used as a biomarker for future cardiovascular disease. Herein we review the studies reporting a causative role for vitamin D in cardiovascular disease.

20 February 2017 in Updates in Surgery
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Journal Article
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GSGeorgios C. Sotiropoulos
Georgios C. Sotiropoulos
APAnastasia Prodromidou
Anastasia Prodromidou
IKIoannis D. Kostakis
Ioannis D. Kostakis
Nikolaos MachairasNikolaos Machairas
Nikolaos Machairas

7 February 2017 in Frontiers in Surgery
Verified
Journal Article
Open access
EMEvangelos P. Misiakos
Evangelos P. Misiakos
GBGeorge Bagias
George Bagias
IPIordanis Papadopoulos
Iordanis Papadopoulos
NDNickolaos Danias
Nickolaos Danias
PPPaul Patapis
Paul Patapis
AMAnastasios Machairas
Anastasios Machairas
Background: Necrotizing fasciitis (NF) is a group of relatively rare infections, usually caused by two or more pathogens. It affects the skin and subcutaneous tissues of lower and upper limbs, perineal area (Fournier’s gangrene) and the abdominal wall. Early diagnosis and aggressive surgical management are of high significance for the management of this potentially lethal disease. Methods: We conducted a retrospective study in patients who presented,during the last decade,at four University Surgical Departments in the area of Athens, Greece, with an admission diagnosis of NF. Demographic, clinical and laboratory data were gathered, and the preoperative and surgical treatment, as well as the postoperative treatment was analyzed for these patients. Results: A total of 62 patients were included in the study. The mean age of patients was 63.7 (47 male patients). Advanced age (over 65 years) (P9. Surgical debridement was performed in all patients (mean no. of repeated debridement 4.8), and in 16 cases (25.8%) the infected limb was amputated. The mean length of hospital stay was 19.7 days, and the overall mortality rate of our series was 17.7%. Conclusions: Diagnosis of NF requires high suspect among clinicians, as its clinical image is non-specific. Laboratory tests can depict the severity of the disease; therefore they must be carefully evaluated. Urgent surgical debridement is the mainstay of treatment in all patients; the need of repetitive surgical debridement is undisputed.

10 September 2020 in BMJ Open
Verified
Journal Article
Open access
PDF file
KFKa Siu Fan
Ka Siu Fan
SGShahi Abdul Ghani
Shahi Abdul Ghani
Nikolaos MachairasNikolaos Machairas
Nikolaos Machairas
LLLorenzo Lenti
Lorenzo Lenti
KFKa Hay Fan
Ka Hay Fan
DRDimitri Aristotle Raptis
Dimitri Aristotle Raptis
Objective: To evaluate the quality of information regarding the prevention and treatment of COVID-19 available to the general public from all countries. Design: Systematic analysis using the ‘Ensuring Quality Information for Patients’ (EQIP) Tool (score 0–36), Journal of American Medical Association ( JAMA ) benchmark (score 0–4) and the DISCERN Tool (score 16–80) to analyse websites containing information targeted at the general public. Data sources: Twelve popular search terms, including ‘Coronavirus’, ‘COVID-19 19’, ‘Wuhan virus’, ‘How to treat coronavirus’ and ‘COVID-19 19 Prevention’ were identified by ‘Google AdWords’ and ‘Google Trends’. Unique links from the first 10 pages for each search term were identified and evaluated on its quality of information. Eligibility criteria for selecting studies: All websites written in the English language, and provides information on prevention or treatment of COVID-19 intended for the general public were considered eligible. Any websites intended for professionals, or specific isolated populations, such as students from one particular school, were excluded, as well as websites with only video content, marketing content, daily caseload update or news dashboard pages with no health information. Results: Of the 1275 identified websites, 321 (25%) were eligible for analysis. The overall EQIP, JAMA and DISCERN scores were 17.8, 2.7 and 38.0, respectively. Websites originated from 34 countries, with the majority from the USA (55%). News Services (50%) and Government/Health Departments (27%) were the most common sources of information and their information quality varied significantly. Majority of websites discuss prevention alone despite popular search trends of COVID-19 treatment. Websites discussing both prevention and treatment (n=73, 23%) score significantly higher across all tools (p<0.001). Conclusion: This comprehensive assessment of online COVID-19 information using EQIP, JAMA and DISCERN Tools indicate that most websites were inadequate. This necessitates improvements in online resources to facilitate public health measures during the pandemic.