Dexmedetomidine associated with lower levels of oxidative stress in CABG patients, finds study

Patients with coronary artery disease generally rely on coronary artery bypass grafting (CABG) surgery for treatment. In cardiac procedures, oxidative stress levels can rise due to factors such as the CPB pump, ischemia, reperfusion injury, hemolysis, and neutrophil activation. Oxidative stress is linked to various health conditions, surgical interventions, and medications administered before, during, and after surgery. Recent study investigated the effects of dexmedetomidine, an alpha-2 agonist anesthetic agent, on oxidative stress in patients undergoing coronary artery bypass grafting (CABG) surgery. Thiol-disulfide homeostasis (TDH) was used as a biomarker to assess oxidative stress, as it plays a crucial role in antioxidant defense and can detect ischemia status in tissues.

The study included 60 patients undergoing elective on-pump CABG surgery, divided into two groups: those receiving dexmedetomidine (Group D) and those not receiving dexmedetomidine (Group C). Blood samples were collected at three time points: 30 minutes before anesthesia induction (T1), 30 minutes after aortic cross-clamp removal (T2), and at the end of surgery (T3). Thiol-disulfide homeostasis was assessed using a novel automated method.

The results showed that in patients receiving dexmedetomidine, lower postoperative levels of disulfide, disulfide/native thiol, and disulfide/total thiol, along with higher native thiol/total thiol, were observed compared to the control group. Postoperative native thiol and total thiol levels were similar for both groups.

The study found that the difference in native thiol levels between T1 and T2 was significantly smaller in the dexmedetomidine group compared to the control group. Additionally, the differences in native thiol and disulfide levels between T1 and T3 were also significantly smaller in the dexmedetomidine group.

Conclusion

The authors conclude that the use of dexmedetomidine in CABG surgery was associated with lower levels of oxidative stress, as evidenced by the thiol-disulfide homeostasis measurements. They suggest that the positive effects of dexmedetomidine on oxidative stress could be beneficial in CABG surgery and that further studies in larger patient cohorts are warranted to explore the clinical utilization of dexmedetomidine.

Key Points

1. The study investigated the effects of dexmedetomidine, an alpha-2 agonist anesthetic agent, on oxidative stress in patients undergoing coronary artery bypass grafting (CABG) surgery.

2. Thiol-disulfide homeostasis (TDH) was used as a biomarker to assess oxidative stress, as it plays a crucial role in antioxidant defense and can detect ischemia status in tissues.

3. The study included 60 patients undergoing elective on-pump CABG surgery, divided into two groups: those receiving dexmedetomidine (Group D) and those not receiving dexmedetomidine (Group C).

4. In patients receiving dexmedetomidine, lower postoperative levels of disulfide, disulfide/native thiol, and disulfide/total thiol, along with higher native thiol/total thiol, were observed compared to the control group. Postoperative native thiol and total thiol levels were similar for both groups.

5. The difference in native thiol levels between the time before anesthesia induction (T1) and the time after aortic cross-clamp removal (T2) was significantly smaller in the dexmedetomidine group compared to the control group. Similarly, the differences in native thiol and disulfide levels between T1 and the end of surgery (T3) were also significantly smaller in the dexmedetomidine group.

6. The authors conclude that the use of dexmedetomidine in CABG surgery was associated with lower levels of oxidative stress, as evidenced by the thiol-disulfide homeostasis measurements, and suggest that the positive effects of dexmedetomidine on oxidative stress could be beneficial in CABG surgery, warranting further studies in larger patient cohorts.

Reference –

Ozguner, Y., Altınsoy, S., Kültüroğlu, G. et al. The effects of dexmedetomidine on thiol/disulphide homeostasis in coronary artery bypass surgery: a randomized controlled trial. BMC Anesthesiol 24, 402 (2024). https://doi.org/10.1186/s12871-024-02794-1