The effect of remifentanil and dexmedetomidine on dynamic thiol/disulfide balance in patients undergoing coronary artery bypass surgery: a prospective case-control study.

OBJECTIVE: It is established that the balance of serum thiols is disrupted in favor of oxidants in coronary artery disease, and the cardiopulmonary bypass pump used during coronary artery bypass surgery disrupts this balance in favor of oxidants. In this study, we investigated the antioxidant effects of remifentanil or dexmedetomidine on thiol-disulfide balance and paraoxonase-1 (PON-1) levels during on-pump coronary artery bypass surgery. PATIENTS AND METHODS: A total of 100 patients who underwent on-pump coronary artery bypass grafting surgery between May 2018 and December 2018 were included in the study. Patients were divided into two groups: the remifentanil group (Group R) and the dexmedetomidine group (Group D). Venous blood samples were obtained from the patients after induction of anesthesia [Time 1 (T-1)], then after cross-clamping of the aorta (T-2), after removal of the cross-clamp (T-3), 10 minutes after the end of protamine infusion (T-4), and 24 hours postoperatively (T-5). Serum total thiol, native thiol, disulfide, and PON-1 levels were evaluated. RESULTS: Total thiol, disulfide, PON-1, native thiol/total thiol, total thiol/disulfide, and native thiol/disulfide levels were similar between the two groups. Native thiol levels were statistically significantly higher in group D compared to group R at T-3 and T-5 (p = 0.017 and p = 0.027, respectively). When T-1 and T-5 times were compared in intragroup measurements, disulfide levels were significantly lower, and native thiol/total thiol ratios were significantly higher at T-5 (p < 0.001). CONCLUSIONS: In conclusion, in light of the data obtained from this study, it can be concluded that dexmedetomidine used during surgery has a better contribution to oxidant-antioxidant balance than remifentanil in patients undergoing coronary artery bypass surgery with the on-pump method.

Blue rubber bleb nevus syndrome.

A 26-yr-old man was admitted with malaise and melena. During the physical examination, six hemangiomas were spotted on the skin, and laboratory evaluations proved the existence of severe iron deficiency anemia (Hb 2.9 g/dl). Upper endoscopy and small bowel follow-through revealed no pathology. Colonoscopy documented the presence of a blue-red cavernous hemangioma, 1 cm in diameter, at the splenic flexura. The skin and colonic lesions were typical; thus, blue-rubber-bleb-nevus syndrome was diagnosed. The patient was given blood transfusions followed by oral iron supplementation. He refused further evaluation or surgery and is still fine after a follow-up period of 6 months. Here, we present a discussion of this case, together with a detailed review of the literature.