Remote Ischemic Preconditioning as a New Method of Nephroprotection

Study Overview
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Brief Summary
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Remote ischemic preconditioning (RIPC), elicited by brief episodes of ischemia and reperfusion in distant tissue, offers a protection against acute kidney injury (AKI) in patients after cardiac surgery. Investigators conducted a prospective, randomized, controlled clinical trial to assess whether RIPC reduces the incidence of AKI measured by standard way using serum creatinine concentration (SCr) and with use of serum level of neutrophil gelatinase-associated lipocalin (NGAL) as a new potential biomarker of a kidney injury. Moreover the aim of investigation was to analyse the safety and clinical outcomes of RIPC after elective, isolated, primary off-pump coronary artery bypass graft surgery (OPCAB).

Detailed Description
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Cardiac surgery patients have a high risk of AKI. The development of AKI is associated with higher mortality and a higher risk for complications in patients undergoing cardiac surgery. However, there are no effective clinical strategies for preventing prevalence of AKI. RIPC as a simple, inexpensive way of protecting tissues against ischemic damage, may also reduce kidney injury. That makes RIPC under the area of interests of many researches which apply this method to prevent AKI. Investigators conducted a single-center, double-blind trial involving patients at high risk of postoperative AKI, in which want to check wether RIPC reduce the prevalence of AKI, according Kidney Disease: Improving Global Outcomes (KDIGO) definition, by increase in SCr. Furthermore researchers want to investigate a benefit from RIPC in reduction of level of SCr and higher glomerular filtration rate (GFR) 72 hours after off-pump coronary artery bypass as well as reduction of postoperative expression of NGAL an early biomarker of AKI.

Official Title
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Remote Ischemic Preconditioning as a New Method of Nephroprotection in Patients Undergoing Cardiac Surgery

Conditions
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Acute Kidney Injury

Intervention / Treatment
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* Procedure: remote ischemic preconditioning
* Procedure: no - remote ischemic preconditioning


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Human patients with coronary artery disease. Exclusion Criteria: history of cardiac surgery, acute myocardial infarction up to 7 days before surgery, chronic kidney disease in 4th or 5th stadium (eGFR<30 ml/min/1,73m2), peripheral vascular disease affecting upper limbs, history of severe injuries and surgeries in 2 months before cardiac surgery, history of cancer, acute inflammation during hospitalization, chronic autoimmunology diseases, dialysis patients.

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patients with RIPC<br>intervention: remote ischemic preconditioning - three cycles of 5-min ischemia, achieved by inflation of blood-pressure cuff to 200 mmHg, followed by 5-min reperfusion while the cuff was deflated were applied to the upper left arm. | Procedure: remote ischemic preconditioning<br>* The remote ischemic preconditioning protocol described before began after anesthesia induction, and was completed prior to the start of surgery.<br>* Other names: RIPC;|
| Sham Comparator: Patients without RIPC<br>intervention: no - remote ischemic preconditioning - in controls, the cuff was placed around the arm but not inflated. | Procedure: no - remote ischemic preconditioning<br>* The sham - remote ischemic preconditioning protocol described before began after anesthesia induction, and was completed prior to the start of surgery.<br>* Other names: no-RIPC;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of acute kidney injury within 72 hours after cardiac surgery | increase in serum creatinine level by more than 50% or more than 0.3mg/dL from baseline within 72 h after surgery | 72 hours after cardiac surgery | 
| NGAL level | increased NGAL level within 3 hours after cardiac surgery | 3 hours after cardiac surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| length of hospitalization | time until discharge from the hospital | through hospitalization completion, an average of 14 days | 
| length of intensive care unit (ICU) stay | time until discharge from ICU | through ICU stay completion, an average of 5 days | 
| ventilation time | time of mechanical ventilation | through ICU stay completion, an average of 5 days | 
| occurrence of postoperative atrial fibrillation | incidence of atrial fibrylation in continous electrocardiogram registration | through ICU stay completion, an average of 5 days | 
| time of renal replacement therapy | days of renal replacement therapy | through ICU stay completion, an average of 5 days | 
| death | death from any cause | from date of randomization until the date of death from any cause, assessed up to 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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remote ischemic preconditioning, cardiac surgery-associated acute kidney injury, neutrophil gelatinase-associated lipocalin