ABSTRACT
Background: Considering the preventative effect of various medications on such complications after surgery, the present study evaluated the effect of two different dexmedetomidine doses on the prevention of nausea and vomiting in discectomy surgery. Materials and Methods: The present controlled, double-blind clinical trial was performed on 135 patients that were candidates for discectomy surgery under spinal anesthesia, which were randomly allocated into three groups. Two different dexmedetomidine doses of 0.2 and 0.5 mcg/kg/h were intravenously administered using an infusion pump for 10 min in the first (DEX-0.2 group) and second (DEX-0.5 group) groups, respectively, with the third placebo group being used as a control group. Hemodynamic parameters, the severity of nausea and vomiting, and the incidence of complications were evaluated and recorded up to 24 h after surgery. Results: The results of the present study revealed that, 20 min after the intervention, the severity of nausea and vomiting in the control group (with the mean of 1.95 ± 1.58) was significantly higher than that of the DEX-0.2 and DEX-0.5 groups with the means of 1.52 ± 1.11 and 1.27 ± 0.99, respectively (P = 0.010). In addition, no significant difference was found between the two dexmedetomidine doses in terms of the severity of nausea and vomiting (P > 0.05). Conclusion: According to the results of the present study, a low dose of dexmedetomidine may be a more preferable choice as a preventive drug in the incidence of nausea and vomiting in discectomy surgery due to its lower complications, further reduction of nausea and vomiting, and more desirable hemodynamic stability.
ABSTRACT
In late 2019, a new member of the Coronaviridae family, officially designated as "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), emerged and spread rapidly. The Coronavirus Disease-19 (COVID-19) outbreak was accompanied by a high rate of morbidity and mortality worldwide and was declared a pandemic by the World Health Organization in March 2020. Within the Coronaviridae family, SARS-CoV-2 is considered to be the third most highly pathogenic virus that infects humans, following the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV). Four major mechanisms are thought to be involved in COVID-19 pathogenesis, including the activation of the renin-angiotensin system (RAS) signaling pathway, oxidative stress and cell death, cytokine storm, and endothelial dysfunction. Following virus entry and RAS activation, acute respiratory distress syndrome develops with an oxidative/nitrosative burst. The DNA damage induced by oxidative stress activates poly ADP-ribose polymerase-1 (PARP-1), viral macrodomain of non-structural protein 3, poly (ADP-ribose) glycohydrolase (PARG), and transient receptor potential melastatin type 2 (TRPM2) channel in a sequential manner which results in cell apoptosis or necrosis. In this review, blockers of angiotensin II receptor and/or PARP, PARG, and TRPM2, including vitamin D3, trehalose, tannins, flufenamic and mefenamic acid, and losartan, have been investigated for inhibiting RAS activation and quenching oxidative burst. Moreover, the application of organic and inorganic nanoparticles, including liposomes, dendrimers, quantum dots, and iron oxides, as therapeutic agents for SARS-CoV-2 were fully reviewed. In the present review, the clinical manifestations of COVID-19 are explained by focusing on molecular mechanisms. Potential therapeutic targets, including the RAS signaling pathway, PARP, PARG, and TRPM2, are also discussed in depth.
