Evaluating sedative effects of dexmedetomidine and morphine in the patients with opioid use disorder undergoing cataract surgery.

BACKGROUND: Considering that patients with opioid dependence are at higher risk of inadequate sedation during operations, and the rescue analgesia in these patients are usually greater than the general population; the aim of this study was comparison of sedation quality of dexmedetomidine and morphine in patients with opioid use disorder undergoing cataract surgery. METHODS: This clinical trial was conducted on 60 patients with opioid use disorder underwent cataract surgery that were referred to Feiz Hospital, Isfahan, Iran in 2018. Patients were randomly divided into two groups as the dexmedetomidine group started 1 µg/kg dexmedetomidine in 10 minutes before surgery and then continued with 0.5 µg/kg/h while the morphine group received 0.1 mg/kg of morphine before surgery. Sedation score, pain intensity, hemodynamic parameters, analgesic request and side effects were compared in the two groups. RESULTS: There was no significant differences between groups based on Ramsay score before, during and after surgery (P > 0.05), the pain intensity in the morphine group was significantly lower during the recovery period than dexmedetomidine group, the duration of recovery and sedation in the morphine group was significantly more than the dexmedetomidine group, and nausea and vomiting and eye pain in the morphine group were significantly higher than dexmedetomidine (P < 0.05). CONCLUSION: Morphine usage was more effective in pain relief than dexmedetomidine in patients with opioid use disorder undergoing cataract surgery, but the complications and recovery time were higher in morphine usage. Also the sedation was similar in both groups.

Flow-Mediated Dilation, a Marker of Endothelial Cell Dysfunction, in Patients with Pulmonary Hypertension.

Background: Flow-mediated dilation (FMD) is considered a marker of endothelial cell dysfunction (ECD) and has been mostly evaluated in coronary artery disease. The role of ECD in the pathogenesis of pulmonary hypertension (PH) is not well-known. This study sought to evaluate the relationship between FMD and PH. Materials and Methods: In this cross-sectional study, the FMD of the brachial artery was measured in 40 confirmed PH patients. Meanwhile, echocardiographic findings, the 6-minute walk test (6MWT), and serum pro-brain natriuretic peptide (pro-BNP) level were evaluated. Overall, 20 patients accomplished all evaluations, and their data were analyzed using SPSS software (version 23). Results: There was an inverse relationship between pro-BNP and 6MWT (r<0, P<0.05). A significant direct relationship was observed between left ventricular ejection fraction and FMD (P=0.031). Right ventricular (RV) dilation was significantly correlated with pro-BNP (P=0.046). There was a significant direct correlation between RV function and FMD and a significant inverse relationship between pro-BNP and FMD (P=0.05). The independent t-test showed no relationship between FMD and syncope (P=0.75). Conclusion: Endothelial cell function, which can be evaluated by FMD, was involved in patients with PH. The FMD and 6MWT were helpful as objective prognostic markers in PH. Furthermore, pro-BNP was a noninvasive indicator in the diagnosis of RV systolic dysfunction.