Effect of Remote Ischemic Preconditioning on Acute Kidney Injury in Patients Undergoing Heart Valve Replacement Surgery With Cardiopulmonary Bypass

The purpose of this study is to study the effect of remote ischemic preconditioning on acute kidney injury in patients undergoing heart valve replacement surgery with cardiopulmonary bypass.

Hypothesis : RIPC using tourniquet might be a simple technique with the benefit to provide renal protection without disturbing operating procedure and prolongation of total operating time.

Inclusion Criteria:

• patients undergoing complex valve surgery.

Exclusion Criteria:

• older than 80 years
• those with left main disease >50%, or hepatic or pulmonary disease
• active infective endocarditis
• left ventricular ejection fraction <30%
• myocardial infarction (MI) within 3 weeks
• pre-existing renal dysfunction (serum creatinine (Cr) level >1.4 mg/dl), and those with peripheral vascular disease affecting the lower limbs.