A Comparison of Different Doses of Dexmedetomidine for Myocardial Protection in Percutaneous Coronary Interventional Patients

Introduction: Dexmedetomidine has been shown to have a myocardial protective effect in off-pump coronary artery bypass patients. However, the same dosage of dexmedetomidine could not elicit a myocardial protective effect in percutaneous coronary intervention patients. The aim of this study was to assess the effect of different doses of dexmedetomidine when used for myocardial protection in percutaneous coronary interventional patients. Methodology: 240 patients (Group D1, treated with dexmedetomidine [n=80]; Group D2, treated with dexmedetomidine [n=80]; and the control group [C; n=80]) were enrolled in the study. Dexmedetomidine was administered over 15 minutes in the respective doses in Groups D1 and D2 at the start of the procedure, while normal saline was given to patients in Group C. Maintenance of dexmedetomidine/NS was started at 0.5 µg/kg/hour in the groups until 30 minutes post-procedure. Creatine phosphokinase (CPK) and CPK-MB, heart rate (HR), mean blood pressure (MAP), and sedation score were noted at baseline (T0), 6 hours (T1), 12 hours (T2), and 24 hours (T3) after the loading dose. Results: MAP and HR significantly decreased in D1 and D2 compared to C (p<0.05). None of the patients in D1 had a reduction in MAP <20% and HR <50 bpm; however, 3 patients in D2 had a clinically significant reduction in MAP, and 5 patients had HR <50 bpm. The patients in D2 were more sedated compared to patients in D1 and C. The difference in CPK and CPK-MB was significant at 6 hours, 12 hours, and 24 hours in D2. Conclusion: Dexmedetomidine 2 µg/kg provides myocardial protection compared to 1 µg/kg, but at the cost of a clinically significant decrease in MAP and HR. Patients who received dexmedetomidine 2 µg/kg were more sedated compared to patients receiving 1 µg/kg, warranting greater care during and post-procedure.