Studying the effects of dexmedetomidine on clinical outcomes and renal function after heart surgery

The aim of the current study is to investigate the effects of dexmedetomidine medication on clinical outcomes and renal function following cardiac surgeries.

Controlled clinical trial, parallel groups, double-blinded, randomized

This study is to be conducted in the Rajaie Cardiovascular Center at Tehran, Iran. The study includes two parallel randomly-assigned groups of low and high dose dexmedetomidine. Patients and the outcome assessors are blinded to the allocation groups.

Inclusion criteria: Age over 18 years old, candidacy for open heart surgery with cardiopulmonary bypass, informed consent for participation in the study Exclusion criteria: History of severe renal disease or renal failure, history of inflammatory or autoimmune disease

Control group receiving low dose Pfizer company's dexmedetomidine (0.5 ug/kg/hr) continuously once from anesthesia induction till the end of operation; Treatment group receiving high dose Pfizer company'sdexmedetomidine (0.75 ug/kg/hr) continuously once from anesthesia induction till the end of operation

Hemodynamic condition, urine output, blood urea nitrogen and creatinine, mechanical ventilation time and intensive care unit stay, operation and cardiopulmonary bypass duration, blood and blood products need, inotrope need, diuretic needs in operation room and intensive care unit

For randomization, researchers use the Stratified Block randomization method and randomize blocks of 3 to 4 people, and the Random Number Generator as the randomization tool. The method of making random sequences is also stratified according to the inotropic drug intake. To conceal the study from the patient and the main physician of the study (double-blind), the allocation of subjects and drugs in the two groups is done by a trained anesthetic technician that records all the cases initially and the final evaluator of the patient has no information on the type of the prescribed drug. Finally, the statistical information of the two groups is given to the analyst, which is not blind to the groups.

Patients are unaware of the groups they were allocated into. They receive the medication during anesthesia. Assessment of the target outcomes are performed with the trained nursing staff who are unaware of the groups. Outcome assessors who fill the questionnaires are not informed regarding the patient allocation.