Effect of Dexmedetomidine on Postoperative Renal Function in Infective Endocarditis Patients Undergoing Open Heart Surgery

Study Overview
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Brief Summary
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Acute kidney injury is major complication after open heart surgery. The cause of acute kidney injury following open heart surgery is related to activation of sympathetic nervous system, decrease of renal blood flow, ischemia-reperfusion injury and systemic inflammatory response. Infective endocarditis patients undergoing open heart surgery have systemic inflammatory response associated with infective endocarditis. And the inflammatory response can be aggravated by cardiopulmonary bypass. The incidence of acute kidney injury following open heart surgery due to infective endocarditis was 50% in a previous report. And this acute kidney injury was related to the poor outcome and high mortality. Thus, the preventive method to protect kidney function will be needed in the patients with infective endocarditis undergoing open heart surgery. Dexmedetomidine is a selective α2-agonist and has sedative, analgesic, and CNS depressive effect. And several experimental study demonstrated the renal protective effect. Intraoperative dexmedetomidine administration can reduce the amount of anesthetics needed and suppress the sympathetic response resulted by surgical stimulation. And dexmedetomidine was reported to reduce the level of serum cortisol, epinephrine and norepinephrine during the operation. Thus, these effects of dexmedetomidine can be expected to reduce the incidence of acute kidney injury. Therefore, the investigators hypothesized that dexmedetomidine has renal protective effect and this effect might be related to the suppression of inflammatory response. Thus, the investigators will evaluate the incidence of acute kidney injury and the incidence of major adverse kidney events (MAKE) after open heart surgery due to infective endocarditis and the level of inflammatory mediators. The primary end point of this study is the incidence of acute kidney injury after open heart surgery due to infective endocarditis. And secondary end point is the incidence of MAKE, the level of cystatin C which is related to the renal function, the level of inflammatory mediator and the postoperative morbidities.

Conditions
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Infective Endocarditis

Intervention / Treatment
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* Drug: dexmedetomidine
* Drug: Normal saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with infective endocarditis patients who are scheduled to undergo open heart surgery Exclusion Criteria: chronic kidney disease taking high dose steroid (>10mg/day prednisolone or equivalent) age under 20 years cognitive dysfunction disabling mental change disorder unable to communicate or speak Korean

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: dexmedetomidine group<br> | Drug: dexmedetomidine<br>* Randomly selected patients of the dexmedetomidine group are given intravenous 0.4mcg/kg/h of dexmedetomidine from the beginning of the anesthesia to postoperative 1 day.<br>|
| Placebo Comparator: Control group<br> | Drug: Normal saline<br>* Group given intravenous 0.4mcg/kg/h of normal saline from the beginning of the anesthesia to postoperative 1 day.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of acute kidney injury |  | 1 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cystatin C level | serum cystatin C level (mg/L) | postoperative day 1,2,3 and 5 | 
| inflammatory mediator(IL-6) level | serum inflammatory mediator (IL-6(pg/mL) | postoperative day 1,2,3 and 5 | 
| inflammatory mediator(CRP) level | serum inflammatory mediator (CRP(mg/L)) | postoperative day 1,2,3 and 5 | 
| inflammatory mediator(WBC) level | Serum WBC(/microL) level | postoperative day 1,2,3 and 5 | 
| inflammatory mediator(neutrophil count) level | serum inflammatory mediator (neutrophil count(/microL)) level | postoperative day 1,2,3 and 5 | 
| serum norepinephrine/epinephrine level(ng/mL) |  | postoperative day 1,2,3 and 5 | 
| intraoperative hemodynamics measured by amount of used vasopressors(mL) |  | postoperative day 1,2,3 and 5 | 
| intraoperative fluid intake and output | intraoperative intake and output measured by the amount of fluid(crystalloid/colloid)(mL) and blood administered(mL) | postoperative day 1,2,3 and 5 | 
| postoperative complications | postoperative complications such as development of myocardial infarction, arrhythmia, cerebrovascular accident, wound infection, and mortality. | postoperative day 1,2,3 and 5 | 
| Major adverse kidney events (MAKE) |  | 3month, 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Infective endocarditis, acute kidney injury, dexmedetomidine