Does dexmedetomidine provide cardioprotection in coronary artery bypass grafting with cardiopulmonary bypass? A pilot study.
OBJECTIVE
The purpose of this pilot study was to evaluate whether dexmedetomidine has a cardioprotective effect during coronary artery bypass graft surgery with cardiopulmonary bypass (CPB).


DESIGN
A prospective, double-blind, randomized controlled trial.


SETTING
A university hospital.


PARTICIPANTS
Thirty-eight patients undergoing coronary artery bypass graft surgery.


INTERVENTIONS
Patients were randomized into 2 groups: dexmedetomidine and placebo groups. In the dexmedetomidine group, dexmedetomidine infusion was started by a loading dose of 0.5 μg/kg/10 min, followed by a continuous infusion of 0.5 μg/kg/h. The placebo group received the same volume of saline. Measurements of central venous pressure, mean pulmonary artery pressure (MPAP) and cardiac index were performed before and after dexmedetomidine loading dose and 2, 24 and 48 hours after CPB. Simultaneously, arterial blood was sampled for CK-MB, cardiac troponin T, and N-terminal probrain natriuretic peptide.


MEASUREMENTS AND MAIN RESULTS
CK-MB, cardiac troponin T and N-terminal probrain natriuretic peptide values were elevated in the periods after CPB in both groups (p<0.05) and there were no statistically significant differences between groups. MPAP was decreased in the dexmedetomidine group at the 2nd, 24th and 48th hour after CPB (p<0.001, p<0.001, p = 0.002, respectively). Higher cardiac index values were seen earlier in the dexmedetomidine group than in the placebo group (p< 0.05).


CONCLUSIONS
Myocardial damage was not reduced by administration of 0.5 μg/kg loading dose and 0.5 μg/kg/h infusion of dexmedetomidine. However MPAP tended to be lower in the dexmedetomidine group. Large-scale clinical outcome studies are indicated to confirm the effect of dexmedetomidine.
['Tosun|Zeynep|Z|', 'Baktir|Mehmet|M|', 'Kahraman|Husnu Cemal|HC|', 'Baskol|Gulden|G|', 'Guler|Gulen|G|', 'Boyaci|Adem|A|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D001794:Blood Pressure D002316:Cardiotonic Agents D001026:Coronary Artery Bypass D052279:Creatine Kinase, MB Form D020927:Dexmedetomidine D005260:Female D006439:Hemodynamics D006801:Humans D006993:Hypnotics and Sedatives D008297:Male D008875:Middle Aged D020097:Natriuretic Peptide, Brain D010446:Peptide Fragments D010865:Pilot Projects D011229:Preanesthetic Medication D020107:Troponin T
dexmedetomidine coronary artery bypass grafting cardiopulmonary bypass cardioprotective effect