Nazire Ates Ayhan

Dr. Nazire Ates Ayhan

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

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

Representative Publications

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22 September 2021 in Balkan Medical Journal
Verified
Journal Article
Open access
KGKursat Gundogan
Kursat Gundogan
İAİsmail Hakkı Akbudak
İsmail Hakkı Akbudak
PHPervin Hancı
Pervin Hancı
BHBurcin Halaci
Burcin Halaci
STSahin Temel
Sahin Temel
ATArzu Topeli
Arzu Topeli
There are limited data on the long-term outcomes of COVID-19 from different parts of the world. To determine risk factors of 90-day mortality in critically ill patients in Turkish intensive care units (ICUs), with respiratory failure. Retrospective, observational cohort. Patients with laboratory-confirmed COVID-19 and who had been followed up in the ICUs with respiratory failure for more than 24 hours were included in the study. Their demographics, clinical characteristics, laboratory variables, treatment protocols, and survival data were recorded. A total of 421 patients were included. The median age was 67 (IQR: 57-76) years, and 251 patients (59.6%) were men. The 90-day mortality rate was 55.1%. The factors independently associated with 90-day mortality were invasive mechanical ventilation (IMV) (HR 4.09 [95% CI: [2.20-7.63], P < .001), lactate level >2 mmol/L (2.78 [1.93-4.01], P < .001), age ≥60 years (2.45 [1.48-4.06)], P < .001), cardiac arrhythmia during ICU stay (2.01 [1.27-3.20], P = .003), vasopressor treatment (1.94 [1.32-2.84], P = .001), positive fluid balance of ≥600 mL/day (1.68 [1.21-2.34], P = .002), PaO2/FiO2 ratio of ≤150 mmHg (1.66 [1.18-2.32], P = .003), and ECOG score ≥1 (1.42 [1.00-2.02], P = .050). Long-term mortality was high in critically ill patients with COVID-19 hospitalized in intensive care units in Turkey. Invasive mechanical ventilation, lactate level, age, cardiac arrhythmia, vasopressor therapy, positive fluid balance, severe hypoxemia and ECOG score were the independent risk factors for 90-day mortality.

29 August 2025 in Medicine
Verified
Journal Article
Open access
HAHatice Ağir
Hatice Ağir
NANazire Ates Ayhan
Nazire Ates Ayhan
Sarcopenia is a disease characterized by loss of both muscle mass and muscle function and is very common in patients in the intensive care unit (ICU). The aim was to investigate the relationship between sarcopenia and mortality, nutrition, weakness and functional activity in intensive care patients. This prospective cohort study included patients who underwent ultrasonographic quadriceps muscle thickness measurement 48 hours after admission to the anesthesia ICU. Patients who underwent ultrasonographic quadriceps muscle thickness measurement in the anesthesia ICU were included in the study. Correlation analysis was performed with sarcopenia parameters and clinical conditions (acute physiology and chronic health evaluation [APACHE] II and sequential organ failure assessment [SOFA]), malnutrition (nutritional risk screening 2002 [NRS2002] and nutrition risk in critically ill score [NUTRIC]), frailty (simple questionnaire to rapidly diagnose sarcopenia [SARC-F]), and life activities scales. Fifty-one patients were included in the study. A negative correlation was found between rectus femoris (RF) muscle thickness and Charlson comorbidity index, NUTRIC, NRS2022 and frailty index scores, a negative correlation with SARC-F score, a positive correlation with KATZ score and a positive correlation with Lawron–Brody score ( P < .05). A negative correlation was found between vastus intermedius (VI) muscle thickness and NRS2002 and SARC-F scores, and a positive correlation was found with KATZ score ( P < .05). Ultrasonographic measurement of quadriceps muscle thickness in intensive care patients is a useful evaluation method in patient follow-up in terms of nutritional defect, frailty, daily living activities, and mortality.

24 October 2018 in Turkish Journal of Anesthesia and Reanimation
Verified
Journal Article
Open access
OKOzge Kuzgu
Ozge Kuzgu
SOSevda Ozkardesler
Sevda Ozkardesler
SOSule Ozbilgin
Sule Ozbilgin
MAMert Akan
Mert Akan
BEBekir Ugur Ergur
Bekir Ugur Ergur
RDReci Meseri Dalak
Reci Meseri Dalak
The aim of this study was to investigate the effects of dexmedetomidine before and after ischaemia in diabetic rat kidney ischaemia reperfusion (IR) injury in the experimental diabetic rat model. Data belonging to 35 rats weighing between 250 and 300 g were analysed. Diabetes mellitus (DM) was induced using streptozotocin. Groups had bilateral renal vasculature clamped for 45 min ischaemia before clamps were removed, and 4 hours reperfusion was applied. Rats were divided into five groups: Group I or nondiabetic sham group (n=7), Group II or diabetic sham group (n=7), Group III or diabetic IR group (n=7), Group IV or diabetic IR+prophylactic Dex P (before ischaemia) (n=7) and Group V or diabetic IR+therapeutic Dex T (following reperfusion) (n=7). Dexmedetomidine was administered at a dose of 100 μg kg-1 intraperitoneally. Histomorphological and biochemical methods were used to assess the blood and tissue samples. The proximal tubule injury score in the control sham group was significantly lower than in other groups. The proximal tubule and total cell damage scores of the diabetic IR group were significantly higher than the diabetic IR+Dex T group, and no significant difference was detected in the diabetic IR+Dex P group. The biochemical parameters of the IR group were significantly increased compared to Groups I and II; however, there was no significant reduction in these parameters in the groups administered dexmedetomidine. Although administration of dexmedetomidine after ischaemia in the diabetic rat renal IR model was found to be more effective on the histopathological injury scores compared to preischaemic administration, this study has not shown that dexmedetomidine provides effective and complete protection in DM.

25 February 2025 in Hitit Medical Journal
Verified
Journal Article
Open access
PDF file
NANazire Ates Ayhan
Nazire Ates Ayhan
VHVolkan Hanci
Volkan Hanci
ŞÖŞule Özbilgin
Şule Özbilgin
BYBülent Serhan Yurtlu
Bülent Serhan Yurtlu
Objective: Preoperative anxiety is a prevalent concern among ambulatory surgery patients. Besides controversial findings between preoperative anesthesia evaluation and anxiety in ambulatory surgical patients, its optimal timing on anxiety levels remains unclear. This study aimed to explore the impact of preoperative anesthesia evaluation timing on anxiety levels in patients undergoing ambulatory surgery. Material and Method: A prospective, non-randomized, observational study was conducted between May 2016 and August 2016. Adult patients scheduled for elective surgery under local anesthesia with sedation were included. Participants were divided based on the timing of anesthesia evaluation: Group OP (evaluated before surgery) and Group AS (assessed on the day of surgery). Preoperative anxiety was measured using the Spielberger State-Trait Anxiety Inventory (STAI) and Visual Analog Scale (VAS) at two time points: just before preoperative anesthesia evaluation (Score 1) and immediately before surgery (Score 2). Results: The study comprised 144 patients, with 72 in each group. No significant differences between groups were observed in baseline sociodemographic characteristics (p>0.05), except for significantly older patients in Group OP than those in Group AS (p=0.030). Median STAI-S, STAI-T, and VAS scores (Score 1) showed no significant differences between groups (p>0.05). Both groups significantly increased STAI-S scores between Score 1 and Score 2 measurements (p=0.015 for Group OP and p

25 April 2025 in Medicine
Verified
Journal Article
Open access
SBSinem Bayrakçi
Sinem Bayrakçi
NANazire Ates Ayhan
Nazire Ates Ayhan
AFAhmet FIRAT
Ahmet FIRAT
YBYurdaer Bulut
Yurdaer Bulut
GSGülşah Seydaoğlu
Gülşah Seydaoğlu
EOEzgi Ozyilmaz
Ezgi Ozyilmaz
The utility of lung ultrasound (LUS) in evaluation of coronavirus disease (COVID-19) with pneumonia has not yet been elucidated. The main objective of study is to determine whether LUS can effectively predict the prognosis in intensive care unit (ICU), including mortality and disease severity. It’s also aimed to determine whether LUS will provide a threshold value to predict mortality in COVID-19 cases. In this prospective observational study, 90 patients admitted to the ICU with COVID-19 pneumonia and respiratory failure were included. A LUS cutoff score of 21 on admission demonstrated sensitivity of 97% and specificity of 68% for predicting mortality. Baseline LUS scores were found to be significantly higher in nonsurvivor group(P < .001) whereas APACHE II, sequential organ failure assessment (SOFA), charlson comorbidity index (CCI), nutrition risk in critically ill (NUTRIC) scores, serum lactate, procalcitonin, ferritin, D-dimer levels and heart rate were also significantly found to be higher in nonsurvivor group(P < .05). Overall mean progression-free-survival (PFS) rate was significantly longer in patients with LUS scores < 21, (mean-survival 23.8 days) compared to those with LUS scores ≥ 21 (mean-survival 12.5 days) (P < .05). Multivariate Cox-regression analysis identified a LUS score ≥ 21 was an independent risk factor for mortality during ICU stay (P = .002). LUS performed at ICU admission can serve as a prognostic indicator for patients with COVID-19 pneumonia. By identifying high-risk groups and monitoring these patients closely using LUS, healthcare providers may enhance resource utilization and potentially improve patient outcomes.

13 September 2025 in Metabolites
Verified
Journal Article
Open access
PDF file
EEElif Eygi
Elif Eygi
SBSinem Bayrakçı
Sinem Bayrakçı
OBOnur Bayrakçı
Onur Bayrakçı
NANazire Ates Ayhan
Nazire Ates Ayhan
AAAhmet Atlas
Ahmet Atlas
Recep DokuyucuRecep Dokuyucu
Recep Dokuyucu
Objectives: Gla-rich protein (GRP), a vitamin K-dependent protein, has been increasingly recognized for its dual role in modulating inflammation and inhibiting pathological calcification. Despite its emerging importance in chronic conditions, limited evidence exists regarding its behavior during acute critical illness. This study aimed to investigate the association between GRP, systemic inflammatory markers, oxidative stress (via total thiol oxidation-reduction ratio, TORR), and calcium metabolism in critically ill patients. Materials and Methods: This cross-sectional observational study included 93 critically ill patients admitted to the intensive care unit (ICU) and 60 age- and sex-matched non-critically ill volunteers. Serum GRP levels were measured using ELISA. Other biomarkers including TORR, C-reactive protein (CRP), procalcitonin (PCT), white blood cell count (WBC), immature granulocytes (IGs), and serum calcium were also analyzed. Pearson’s correlation, multivariate linear regression, and ROC analysis were performed to assess the relationships among GRP and biochemical markers, as well as their capacity to differentiate ICU patients from controls. Results: GRP, TORR, CRP, PCT, WBC, IGs, and ferritin levels were significantly elevated in ICU patients compared to the control group, whereas serum calcium levels were markedly reduced (all p < 0.05). GRP levels demonstrated moderate positive correlations with WBC (r = 0.47), neutrophils (r = 0.51), TORR (r = 0.42), CRP (r = 0.30), and IGs (r = 0.46), and a strong negative correlation with calcium (r = −0.63). In multivariate regression, TORR, CRP, WBC, IGs, PCT, and calcium levels showed significant correlations with GRP levels in univariate analysis. ROC analysis revealed that CRP had the highest discriminatory power (AUC = 0.88; 95% CI: 0.82–0.94), followed by TORR (AUC = 0.79; 95% CI: 0.71–0.86), GRP (AUC = 0.76; 95% CI: 0.68–0.84), and IGs (AUC = 0.77; 95% CI: 0.69–0.85), for distinguishing ICU patients from non-critically ill individuals. Conclusions: Our findings demonstrated that GRP is significantly associated with systemic inflammation, oxidative stress, and calcium metabolism disturbances in critically ill patients. The combined evaluation of GRP and TORR may enhance the understanding of inflammatory and oxidative mechanisms in acute critical illness. Although this study did not assess patient outcomes, these biomarkers could serve as promising candidates for future prognostic research in ICU settings.