Dexmedetomidine for Prevention of Skeletal Muscle Ischaemia-Reperfusion Injury in Patients with Chronic Limb Ischaemia Undergoing Aortobifemoral Bypass Surgery: A Prospective Double-blind Randomized Controlled Study

BACKGROUND: Dexmedetomidine is a selective α-2 agonist used for sedation. It has also been shown to have myocardial protective effect and prevent ischemia-reperfusion injury in off-pump coronary artery bypass patients. The aim of our study was to assess the effect of dexmedetomidine for prevention of skeletal muscle ischemia-reperfusion injury in patients undergoing aortobifemoral bypass surgery. METHODOLOGY: Sixty adult patients (Group dexmedetomidine n = 30, Group normal saline n = 30) undergoing aortobifemoral bypass surgery were recruited over 3 months. Randomization was done using a computer-generated random table. The attending anesthesiologist would be blinded to whether the drug/normal saline was being administered. He would consider each unlabeled syringe as containing dexmedetomidine and calculate the volume to be infused via a syringe pump accordingly. Dexmedetomidine infusion (1 mcg/kg) over 15 minutes was given as a loading dose, followed by maintenance infusion of 0.5 mcg/kg/h till 2 h postprocedure in Group dexmedetomidine (D) while the same volume of normal saline was given in the control Group C till 2 h postprocedure. Creatine phosphokinase (CPK) values were noted at baseline (T0), 6 h (T1), 12 h (T2), and 24 h (T3) after the procedure. Hemodynamic variables (heart rate [HR] and mean blood pressure [MAP]) were recorded at T0, T1, T2, and T3. Results were analyzed using unpaired Student's t-test, P < 0.05 was considered statistically significant. RESULTS: MAP and HR significantly decreased in Group D as compared to control group (P < 0.05). However, the decrease was never <20% of the baseline. The CPK values at 6, 12, and 24 h were statistically significant between the two groups. CONCLUSION: Dexmedetomidine prevents skeletal muscle ischemia-reperfusion injury in patients undergoing aortobifemoral bypass surgery.