The dose-related effects of dexmedetomidine on renal functions and serum neutrophil gelatinase-associated lipocalin values after coronary artery bypass grafting: a randomized, triple-blind, placebo-controlled study.
OBJECTIVE
Acute kidney failure after coronary artery bypass grafting (CABG) is a serious complication that increases morbidity and mortality rates. Early detection and prevention of this complication are very important. A novel biomarker named neutrophil gelatinase-associated lipocalin (NGAL) can play an important role in early diagnosis of acute kidney injury. Recent studies on the favourable effects of Dexmedetomidine on cardiac surgery have been published. The aim of this study is to investigate whether there is a dose-dependent positive effect of Dexmedetomidine on neutrophil gelatinase-associated lipocalin levels and renal functions when used after CABG.


METHODS
Our randomized, triple-blinded, placebo-controlled study was conducted among 295 patients scheduled for CABG surgery between August 2009 and March 2011 in a tertiary cardiac and vascular surgery clinic. A total of 90 consecutive patients who met inclusion criteria were randomized and divided into three groups. The first group received a placebo. The second and the third groups received 4 and 8 µg/cc concentration of the Dexmedetomidine infusion, respectively. Infusion rates were regulated to obtain sedation with a Ramsey sedation score of 2 or 3. Patients were regrouped according to the total Dexmedetomidine dose. Statistical analyses of variables including serum neutrophil gelatinase-associated lipocalin values and conventional renal function tests were made for all six possibilities before the blind was broken.


RESULTS
Results of conventional renal function tests were not significantly different. However, neutrophil gelatinase-associated lipocalin levels for the first postoperative day for placebo, low-dose and high-dose Dexmedetomidine groups were 176.8 ± 145.9, 97.7 ± 63.4 and 67.3 ± 10.9 ng/ml, respectively. These values were significantly different among the groups (P <0.001).


CONCLUSIONS
In our study, we found that Dexmedetomidine infusion for sedation after CABG under cardiopulmonary bypass can be useful in the prevention of kidney injury. Conventional renal function tests, including blood urea nitrogen, serum creatinine, urine output and creatinine clearance rate measurements typically may not detect the development of acute kidney dysfunction in the first 48-h postoperative period. Differences were detected in renal function in the early postoperative period and the development of acute kidney injury, as determined by measurements of blood NGAL levels, was significant and dose-dependent.
Department of Cardiovascular Surgery, Manisa State Hospital, Manisa, Turkey balkanay@doctor.com.
Ozan Onur
OO
Balkanay
Department of Cardiovascular Surgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey.
Deniz
D
Goksedef
Department of Cardiovascular Surgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey.
Suat Nail
SN
Omeroglu
Department of Cardiovascular Surgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey.
Gokhan
G
Ipek
D058186:Acute Kidney Injury / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D000209:Acute-Phase Proteins; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001806:Blood Urea Nitrogen; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery*; D003404:Creatinine / Q000097:blood; D019610:Cytoprotection; D020927:Dexmedetomidine / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000627:therapeutic use*; D007262:Infusions, Intravenous; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011518:Proto-Oncogene Proteins / Q000097:blood*; D062606:Tertiary Care Centers; D013997:Time Factors; D016896:Treatment Outcome; D014421:Turkey
D000209:Acute-Phase Proteins; D015415:Biomarkers; D006993:Hypnotics and Sedatives; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D020927:Dexmedetomidine; D003404:Creatinine
Coronary artery bypass grafting; Dexmedetomidine; Kidney injury; Neutrophil gelatinase-associated lipocalin