Browsing by Author "Djuric, Marko (56467826000)"

Background / Aim: In surgery, and especially in the neurosurgical operations, maintenance of cardiovascular stability during and in the phase of the immedi-ate postoperative recovery is of vital importance. The aim of this study was to investigate the effects of continuous esmolol infusion on the values of cardiovascular parameters and quality of the emergence from anaesthesia in neurosurgi-cal patients. Methods: A total of 40 patients of both sexes scheduled for elective supratento-rial surgery were randomly assigned to two groups. Esmolol group received intravenous (iv) infusion of esmolol dissolved in 5 % glucose solution (during the first 5 min at a rate of 0.3 mg/kg/min and thereafter at a rate of 0.1 mg/kg/min), while the ones from the control group received a 5 % glucose solution without esmolol at the same volume and rate. Cardiovascular parameters were regis-tered at critical phases of anaesthesia and operation (induction, intubation, placement of Mayfield frame, craniotomy, skull closure, extubation). Recovery after anaesthesia was assessed based on times of eye opening on command, spontaneous eye opening and regaining of full orientation. Results: Values of systolic blood pressure and heart rate were significantly low-er in the esmolol than in the control group of patients. Although the durations of anaesthesia did not differ, patients from the esmolol group required significantly less opioids and isoflurane and recovered after the anaesthesia significantly faster than the patients in the control group. Conclusion: Ultrashort-acting beta-adrenergic receptor antagonist esmolol, ad-ministered as a continuous iv infusion, assures better cardiovascular stability and smoother emergence from the balanced inhalation general anaesthesia than the control glucose infusion in elective neurosurgical patients. © 2021 Lončar-Stojiljković et al.

Purpose of Review: This review paper shows the controversies of using nitrous oxide in anesthesia of different patient populations. It provides information on nitrous oxide’s potential side effects when used in modern anesthesia during surgery. Recent Findings: The ENIGMA I and ENIGMA II studies showed a significantly increased risk of postoperative nausea and vomiting after nitrous oxide administration. The theory is that nitrous oxide administered at pediatric age may accelerate neuronal apoptosis and lead to cerebral toxicity and behavioral and learning disorders later in life. The side effects associated with the use of nitrous oxide are based on megaloblastic changes associated with vitamin B12 deficiency and reduced methionine synthesis. Summary: In recent years, there have been recommendations to eliminate nitrous oxide from medical use due to its toxicity, possible increase in morbidity and mortality, and adverse environmental effects. Nevertheless, some authors promote its use, mainly because of its analgesic effect. Nitrous oxide can be used for analgesia during epidural catheter placement, labor, and postpartum procedures because it crosses the placenta and is rapidly eliminated in newborns at the onset of respiration. Its widespread use in minor pediatric procedures has been described. Currently, there is insufficient evidence to support or refute the continued use of nitrous oxide in medical practice. Most of the available data show that nitrous oxide is obsolete as an anesthetic gas, which unfortunately reduces the need for its continued use in anesthesia. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

Background: The COVID-19 pandemic revealed an unexpected pattern known as the “smoker’s paradox”, with lower rates of severe disease among smokers compared to non-smokers, highlighting the need for the specific investigation of disease progression in non-smoking populations. Objective: To identify early mortality predictors in non-smoking patients with severe COVID-19 through the evaluation of clinical, laboratory, and oxygenation parameters. Methods: This retrospective observational cohort study included 59 non-smokers hospitalized with COVID-19 between November and December 2020. Clinical parameters, laboratory findings, and respiratory support requirements were analyzed on Days 1 and 7 of hospitalization. ROC curves were constructed to assess the predictive value of the parameters. Results: The overall mortality rate was 54.2%. The seventh-day SOFA score showed the strongest predictive value (AUC = 0.902, p = 0.004), followed by pCO2 (AUC = 0.853, p = 0.012). Significant differences between survivors and non-survivors were observed in acid–base parameters, oxygenation indices, and hematological markers. Mortality rates varied significantly with ventilation type: 84.6% for IMV and 50% for NIMV, with no deaths in HFNC patients. Conclusions: Multiple parameters measured on Day 7 of hospitalization demonstrate significant predictive value for mortality in non-smoking COVID-19 patients, with the SOFA score being the strongest predictor. The type of respiratory support significantly influences outcomes, suggesting the importance of careful ventilation strategy selection. © 2025 by the authors.

Background: The COVID-19 pandemic revealed an unexpected pattern known as the “smoker’s paradox”, with lower rates of severe disease among smokers compared to non-smokers, highlighting the need for the specific investigation of disease progression in non-smoking populations. Objective: To identify early mortality predictors in non-smoking patients with severe COVID-19 through the evaluation of clinical, laboratory, and oxygenation parameters. Methods: This retrospective observational cohort study included 59 non-smokers hospitalized with COVID-19 between November and December 2020. Clinical parameters, laboratory findings, and respiratory support requirements were analyzed on Days 1 and 7 of hospitalization. ROC curves were constructed to assess the predictive value of the parameters. Results: The overall mortality rate was 54.2%. The seventh-day SOFA score showed the strongest predictive value (AUC = 0.902, p = 0.004), followed by pCO2 (AUC = 0.853, p = 0.012). Significant differences between survivors and non-survivors were observed in acid–base parameters, oxygenation indices, and hematological markers. Mortality rates varied significantly with ventilation type: 84.6% for IMV and 50% for NIMV, with no deaths in HFNC patients. Conclusions: Multiple parameters measured on Day 7 of hospitalization demonstrate significant predictive value for mortality in non-smoking COVID-19 patients, with the SOFA score being the strongest predictor. The type of respiratory support significantly influences outcomes, suggesting the importance of careful ventilation strategy selection. © 2025 by the authors.

Background/Aim: Hyperhomocysteinaemia is linked to higher level of acetylcholinesterase (AChE) in brain, but there is insufficient information on influence of homocysteine (Hcy) and gasotransmitters on cardiac AChE. Thus, the aim of this study was to evaluate the influence of certain gasotransmitter inhibitors in Hcy-induced changes on rat cardiac AChE activity. Methods: Research was performed on 72 male Wistar albino rats distributed into 6 groups: 1) Control group - saline (1 ml 0.9% NaCl ip); 2) DL-Hcy (8 mmol/kg ip DL homocysteine (DL-Hcy); 3) L-NAME (10 mg/kg ip Nω-Nitro-L-arginine methyl ester (L-NAME), inhibitor of NO production); 4) DL-PAG (50 mg/kg ip DL-propar- gylglycine (DL-PAG), inhibitor of H2S production); 5) DL-Hcy+L-NAME (8 mmol/ kg ip DL-Hcy + 10 mg/kg ip L-NAME); and 6) DL-Hcy+DL-PAG (8 mmol/kg ip DL-Hcy + 50 mg/kg ip DL-PAG). All tested substances were administered in a single dose, intraperitoneally, 60 minutes before animals’ sacrifice. AChE activity was measured in the rats’ cardiac tissue homogenate. Results: Administration of Hcy and L-NAME induced significant decrease in AChE activity compared with control condition. Administration of DL-PAG, DL-Hcy+L- NAME and DL-Hcy+DL-PAG did not change AChE activity compared with the control group. Conclusion: The effects of acute Hcy administration on the cardiac AChE activity are partially mediated via interaction with tested gasotransmitters. © 2019, Faculty of Medicine, University of Banja Luka. All rights reserved.

Background: The importance of homocysteine (Hcy) is increasingly recognized in last few decades as an independent risk factor for atherosclerosis and thrombosis, but there is lack of data referring to influence of Hcy on plasma oxidative stress parameters as well as the role of gasotransmitters in these effects. Therefore, this study aim was to assess the role of gasotransmitter inhibitors in Hcy-induced effects on plasma oxidative stress in rats. Material and Methods: Study involved 96 male Wistar albino rats divided into 8 groups: 1) Control group - saline (1ml 0.9% NaCl i.p.,); 2) DL-Hcy (8 mmol/kg i.p. DL homocysteine (DL-Hcy); 3) L-NAME (10 mg/kg i.p. Nω-Nitro-L-arginine methyl ester (L-NAME), inhibitor of NO production); 4) ZnPPR IX (30 mol/kg i.p. protoporphyrin IX zinc (ZnPPR IX), inhibitor of CO production); 5) DL-PAG (50 mg//kg i.p. DL-propargylglycine (DL-PAG), inhibitor of H2S production); 6) DL-Hcy+L-NAME (8 mmol/kgi.p. DL-Hcy + 10 mg/kg i.p. L-NAME); 7) DL-Hcy+ZnPPR IX (8 mmol/kgi.p. DL-Hcy + 30 mol/kg i.p. Zn PPR IX), and 8) DL-Hcy+DL-PAG (8 mmol/kg i.p. DL-Hcy + 50 mg//kg i.p. DL-PAG). In all experimental groups, tested substances were administered in a single dose, intraperitoneally, 60 minutes before animals’ euthanasia. In the collected blood samples malondialdehyde concentration, catalase, glutathione peroxidase and superoxide dismutase activity were measured. Results: Applied substances induced rapid and strong increase of plasma antioxidant enzymatic activity probably as a compensatory response to its pro-oxidant influence. Conclusion: The effects of Hcy on the activity of plasma antioxidant enzymes are in part mediated via interaction with gasotransmitters. © 2019 Djuric et al.

Hyperhomocysteinemia (HHC), both basal and after methionine load, may occur due to genetic disorders or deficiencies of nutrients that affect the remethylation or transsulphuration pathways during methionine metabolism. HHC is involved in the pathogenesis of many illnesses as a result of its prooxidative effect and its impairment of antioxidative protection. The aim was to examine the effects of subchronic methionine overload on the body weight and standard biochemical parameters in rat serum and to examine whether simultaneous subchronic intraperotoneal administration of methionine alone or together with L-cysteine or N-acetyl-cysteine resulted in a change in the body weight and biochemical parameters in the rat serum. The research was conducted during a three-week period (male Wistar albino rats, n=36, body weight of approximately 160 g, age of 15-20 days), and the animals were divided into a control group and three experimental groups of 8-10 animals each: a) control group (0.9% sodium chloride 0.1-0.2 ml/day); b) methionine (0.8 mmol/kg/bw/day) (MET group); c) methionine (0.8 mmol/kg/bw/day) + L-cysteine (7 mg/kg/bw/day) (L-cys+MET group); and d) methionine (0.8 mmol/kg/bw/ day) + N-acetyl-L-cysteine (50 mg/kg/bw/day) (NAC+MET group). In addition to the body weight monitoring, the levels of total homocysteine and the standard biochemical parameters in blood samples (plasma or serum) were determined. The results indicated that monitoring the homocysteine levels and standard biochemical parameters in blood could be used for analysis and could provide an excellent guideline for distinguishing between toxic and non-toxic doses of methionine intake, which may be meaningful for clinical applications. © 2016, University of Kragujevac, Faculty of Science. All rights reserved.

Background / Aim: The concept of general balanced anaesthesia was devised in order to assure cardiovascular stability and fast post-anaesthesia recovery. This clinical trial was organised in order to investigate the parameters of cardiovascular function and emergence from anaesthesia in elective ear, nose and throat (ENT) surgery patients. Methods: A total of 40 ASA I and II patients of both sexes scheduled for elective ENT surgery were randomly divided into two equal groups. Both groups received a continuous iv infusion of glucose 5 % solution and in the esmolol group this infusion also contained esmolol. Esmolol infusion rate was 0.3 mg/kg/min during the first 5 min and thereafter 0.1 mg/kg/min. In critical phases of anaesthesia and operation (induction, intubation, first incision, surgical manipulations, wound suture, extubation), systolic and diastolic blood pressure were monitored. Recovery after anaesthesia was assessed based on times of eye opening on command, spontaneous eye opening and regaining of full orientation. Increases in cardiovascular parameters by 20 % of the baseline values or more were treated with iv boluses of fentanyl, alone or with droperidol and, if necessary, by adding isoflurane 0.5 % to the inhalational mixture. Consumption of drugs was recorded. Results: Esmolol assured stable values of cardiovascular parameters that were in most critical phases of anaesthesia and operation lower than in the control group. The duration of anaesthesia did not differ between the groups. In the esmolol group, lower consumption of fentanyl, droperidol and sevoflurane was registered. Patients in the esmolol group emerged from anaesthesia faster than patients in the control group. Conclusion: Continuous iv infusion of esmolol assures better cardiovascular stability, necessitates lower consumption of analgesics and anaesthetics and results in faster emergence from general anaesthesia in elective ENT surgery. © 2022 Lončar-Stojiljković et al.